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HomeMy WebLinkAbout1.0 Preliminary Plan Application• • • • • • • • • • • LAKE SPRINGS RANCH PLANNED UNIT DEVELOPMENT GARFIELD COUNTY, COLORADO PRELIMINARY PLAN SUBMITTAL • • • • • • • • • • • LAKE SPRINGS RANCH PLANNED UNIT DEVELOPMENT Garfield County, Colorado Preliminary Plan Submittal OWNER: Foster Petroleum Corporation DESIGN TEAM: Civil Engineers: Eldorado Engineering Company Glenwood Springs, Colorado Planning: The Land Design Partnership Glenwood Springs, Colorado Soils/Geology: Chen and Associates Soils Engineers Glenwood Springs, Colorado Water Engineering: Date: Wright Water Engineers Glenwood Springs, Colorado June 22, 1979 • • - • • • • • • • • • • Q cpm? :2d y2(�«». mz= September 20, 1979 Board of County Cc:zissioners Garfield County P. 0. Box 640 Glenwood Springs, Colorado RE: Preliminary Plan sutmittal Late Springs Ranch Planned Unit Development Gentlemen: Please find enclosed for your agproval, C� .<. relating to the Preliminary Plan for the L- 2 The property under consideration is under the o P trole. Corporation. is and maps yz ?encs P.P.D. c of Zoster The information has been prepared by a Ec-icn :lac r:or ting of E cocado Engineer, the Land Design Partnershi,, Chan and associates and right sate£ Engineering. The submittal is in co iar iica with the P.U.D. zoning submittal previously approved by the Board. Should the Board require additional information or docomeotation to sugplement the materials contairled harein we will be available to work th your planning staff to provide the same. ars:au Enc. Sincerely, 1 Duncan L. Sinnock Real Estate Investment Manager • • • • • • • • • • • TABLE OF CONTENTS GENERAL INFORMATION Fact Sheet 1 Lake Springs Ranch P.U.D. Zoning Regulations 3 Lake Springs Ranch Subdivision Regulations 6 Covenants 7 Schools/Parks Dedication 7 P-iYSICAL INFORMATION Geology and Soils Summary 8 Vegetation and Wildlife Summary 9 Road Network Summary 11 Drainage Report 12 UTILITY INFORMATION Domestic Water System 14 Wastewater System 21 Underground Utilities 24 Appendix A, Engineering Geology and Preliminary Subsoil Investigation • • • • • • • • • • • *Note that the acreage from the legal description is 441.8 acres. The acreage discrepancy will be resolved when lot sizes are cal- culated at final plat. Gross project density - 0.47 units/acre. Zoning: The subdivision is zoned under a proposed Flanged unit Development currently submitted for consideration by Garfield County. -2- • • • • • • • • • • LAKE SPRINGS RANCH P.U.D. ZONING REGULATIONS Section I. PURPOSE A. To carry out the purposes and provisions of the Garfield County Zoning Resolution, Gar- field County, Colorado and in particular Section 14.00 of the Garfield County Zoning Resolution, as amended, the Lake Springs Ranch P.U.D. Zoning District is further divided into the following zoning district classifications: It/S.F. - Residential/Single Family District R/C.H. - Residential/Cluster Housing District A/O.S. - Agricultural/Open Space District Section II. R/S.F. - RESIDENTIAL/SINGLE FAMILY DISTRICT A. Uses, by right. Single -Family dwelling and customary accessory uses including buildings for shelter or en- closure of small animals or property accessory to use of the lot for single family residential purposes and fences, hedges, Gardens, walls and similar landscape features. Park and Greenbelt. B. Uses, conditional. None C. Uses, special. None D. Minimum lot area. 1 acre E. Maximum Lot Coverage. 15 percent • -3- • • • • F. Minimum Setback Front yard -- 30 feet Side yard -- 20 feet Rear yard -- 50 feet G. Maximum Building Height 25 feet H. Off -Street Parking/Residential Four (4) off-street parking spaces on the same lot for each dwelling unit or one (1) space per 600 square feet of floor area whichever is greater. Section III. R/C.H. - Residential/Cluster Housing District • A. Uses, by right Single -Family dwelling, Duplex dwelling, Triplex dwelling and customary accessory uses including buildings for shelter or enclosure of small animalsorproperty accessory to use of the lot • for residential purposes and fences, hedges, gardens, walls, and similar landscape features. • • • • No more than three dwelling units may exist in the R/C.H. District. Park and Greenbelt. B. Uses, conditional. ' None C. Uses, special. None D. Minimum Cluster Housing lot area. 1. The Cluster Housing Lot shall be as shown on the P.U.D. Plan. 2. Lots within a Cluster Housing Lot shall have no minimum lot area. -4- • • • E. Maximum Coverage of the Cluster Housing District 1. 5 percent of the total District area. F. 2. Lots within the R/C.H. District shall have no coverage limit except that the combined coverage of all internal lots shall not exceed the 5 percent maximum of the total District area. Minimum Setback from the Cluster Housing District Boundary 1. 50 feet • 2. Lots within the R/C.H. District shall have no setback requirements. • • • • • • • G. Maximum Building Height 25 feet H. Off -Street Parking Four (4) off-street parking spaces for each dwelling unit or one (1) space per 600 square feet of floor area, whichever is greater. SECTION IV. A/O.S. - AGRICULTURAL/OPEN SPACE DISTRICT A. Uses, by right. Recreational including, stables, riding arena, kennal, pasture, water impoundments and customary accessory uses including buildings for shelter or enclosure of animals or property employed in any of the above uses. Recreation Vehicle Storage Park and Greenbelt B. Uses, Conditional. None C. Uses, Special None D. Minimum Lot Area 2 acres -5- • • • • • • • • • • • LAKE SPRINGS RANCH SUBDIVISION REGUL?:TIONS Except for the following section of the Garfield County Subdivision Regulations, all provisions of the Garfield County Subdivision Regulations shall be applicable to the Lake Springs Ranch P.U.D. The Section of the said Subdivision Regulation which shall have no applicability is as follows: Section 5.09 • • • • • COVENANTS To further assure the development and continuation of Lake Springs Ranch as a high quality residential area, protective covenants will be recorded along with the final plattings of the P.U.D. Following are topics of parti- cular importance to be included in the covenants. A preliminary draft of these covenants will be provided to the County Planning Department. 1. Architectural Committee - -Building siting - -Site and structural design --Landscaping --Fencing restrictions 2. Lot Use Restrictions - -Residential structure --Garage/storage structure 3. Animals --No horses or livestock on lot - -Dog kenneling requirements 4. Underground Utilities Required • Vehicle Control --Limitations on recreational vehicle storage General Site Maintenance . 7. Noxious Activities 8. Easements 9. Signs 10. Temporary Structures • • • • SCHOOLS/PARKS DEDICATION In accordance with Section 5.11 of the Subdivision Re- gulations of Garfield County, Colorado, as amended, the Lake Springs Ranch P.U.D. owners will cooperate with the Board of County Commissioners to appropriately com- pensate the county for the reasonably necessary public facilities (schools/parks) required by the future residents of the P.U.D. -7- • • • • • • • • • • • GEOLOGY AND SOILS SUVJ ARY Appendix A contains the Engineering Geology and Preliminary Sub- soil investigation conducted on the site by Chen and Associates dated January 30, 1978. The report was performed for a recent Preliminary Plat submittal for the same property but with a dif- ferent development pattern. The report therefore references various blocks and roads which have now been relocated, as evidenced by the site map (Figure 1) in the report, but the basic analysis and conclusions are obviously still valid. Also included at the end of that report for reference are the previous responses of the Colorado Geological Survey. • • • • • • • • • • • VEGETATION AND WILDLIFE SUMMARY The sloping terrain that is proposed for development, which for this discussion will be called the upper slopes, is covered by sage and discontinuous native pasture grass growth with occasional open stands of gambels oak. The lower portions of the site consist of intermittent and permanent ponds and continuous growth of native pasture grasses. These areas have high groundwater tables and are not suitable for development. As a result, these areas have been set aside for open space and common area. The transition zone between the areas, primarily along The Corduroy and County Road 114 and the Van Cleave Road area, has vegetative types common to both the upper slopes and lower areas. This area has been selectively chosen for development such that a buffer zone exists between the developed areas and environmentally sensitive lower areas. With the retention of the lower areas and scattered Agricultural/Open Space areas on the upper slopes, as well as the restricted lot development, the natural vegetative conditions and hence the natural appearance of the area will be retained. Conversations with the Division of Wildlife Officers indicated that this area is generally considered to be an intermediate fall and winter range for deer and forms part of the migratory corridor between seasonal ranges. In that light it was recommended that fencing be restricted to buildings and irrigated land, that dogs be required to be kenneled and not be allowed to roam, both of which have been in- -9- • eluded in the Zoning Regulations. With these restrictions, the im- pact on the deer population will be minimized. Prohibition of horses on individual lots was recommended to avoid • destruction of the natural vegetation necessary for the small mammal and bird population. • • • • • • • • Grouse populations have been indentified near the Lake Springs Ranch site but not on the site. These birds were identified as being possibly impacted, if they do exist on the site, by the development. -1C- • • • • • • • • • • • ROAD NETWORK SUI' ARY The proposed road network is shown on the Plan and Profile Sheets and the Site Plan. The road system has been designed to conform both horizontally and vertically to the existing topography to the greatest extent possible to minimize cut and fill requirements, minimize roadway scars and still remain within the County design standards. Typical cross-sections are also depicted graphically in the Plans. In addition to the proposed typical sections are two sections taken at critical cut and fill locations. The section from Quigley Road indicates the most severe construction situation in the development in terms of natural ground surface and maximum fill. More typical is a cut or fill situation of a maximum 2' to 3' or less across the front of individual lots. Also shown is a cross-section from Valley View Road showing the situation at a culvert crossing. It is proposed to retain the horizontal and vertical alignment of County Road 114. County Road 119 will retain its original align- ment until it departs from the northerly boundary of the develop- ment at which point its present location will be vacated. County Road 119 will require some selected upgrading in terms of widening and regraveiing to bring it up to the condition of the other proposed roads. -11- • • • • • DRAINAGE REPORT The on-site drainai7e. patterns will not be altered by the P.U.C. The single family lots proposed are one acre or greater and with a total potential lot development of 10% to 15% maximum and in the majority of lots on the order of 5%. There is ample land area on each lot to prevent encroachment on existing drainage ways. The overland drainage will continue to flow as it presently does, with some minor channeling due to intersecting roadways. The drainage system will be augmented by culvert pipes at road crossings. All culverts were designed to handle a 1 -hour, 25 -year storm occurance using the Rational Formula. The Drainage Plan indicates the location • and size of proposed culverts as well as the projected maximum flows at each point. Culverts will all have minimum slopes of 1% and in most cases will follow the natural slope of the land which is for the most • part 5% or greater. Because of the low density and convenants protecting natural vegetation, there will be minimal increases in the quantity of run-off. • • • The minimum culvert size will be 18". Culverts will be constructed with end sections or headwalls to maximize carrying capacity. Drainage basins considered are shown on the Drainage Plan as well as the larger vicinity map attached hereto. • -12- • - 6- • - \ i J � r ✓a t\ _. / I c 4 s i�- tJC'14 .fJ N' • • • --�\ �. , \E L r � . i• \I -.�, �� rte, ".+ `tiY '2,----- _ - _. ! < - — • ! t co ca_ 1 1/ 1 C,' 3 42- i. -.70;1).7-2:.. , • • DOMESTIC WATER SYSTEM The proposed domestic water system is shown on the Utility Site • Plan. All construction will be in accordance with, and all Plans and Specifications will be reviewed by, the State Health Department. • It is the intent of the Developer to construct and finance the construc- tion of the water system facilities and to transfer orership to the Lake Springs Ranch Hornowner's Association. The Association will be • responsible for the o-eration and maintenance of the system as well as collection of user charges to finance the same. The Association will be organized as a Colorado nor -profit corporation with an elected Board. • The system has been modified slightly from the sketch plan in terms of the physical layout on the ground. The design parameters have rot chanced in terms of sizing, demands, etc., however, to take advantage of the • topography and to reduce the pumping costs, three (3) pressure zones were created such that only the water actually used in the zone will be transferred to that zone. The storage facilities for the upper zone and lower zones (both lower zones are served by the same storage tank) are sized in proportion to the number of units in each zone while main- taining fire protection within each area. The lowest pressure zone is reached through pressure reducing stations from the intermediate zone. The zones were established generally to provide a 90 psi to 30 psi static • • • • -14_ • • • • • • • pressure range within each zone within the topographic _ each zone. The alternative to the pressure zone arranger,ent above is a one storage facility for the entire system and defining the same zones with pressure reducing valves. This has the advantage of reducing the number of pumping facilities and storage tanks but requires more water line and increases pumping costs. This alternative will be fully, evaluated on a cost/effective basis during preparation -of final construction documents. Following is correspondence from Wright 'pater Engineers concerning the water rights for the PLD. The October 20, 1979 letter indicates the three VanCleave rights owned by the Developer_. -re analysis performed to determine the consumptive use in this letter is ro longer valid since tre septic tank treatment referred to is no longer being used in lieu of central treatment. The revised wastewater treatMent scheme has been reviewed by Wright Water Engineers in a letter dated April 2, 1979, and it was found that the water rights available are sufficiert. The Court Case number for the Lake Springs Ranch water system is as • follows: • the change in wastewater treatment, refiled in February, 1979. The • augmentation plan involves transferr r,g the three VanCl eave ri oh =s to • Augmentat i on Plan: W 3571 Wells: 'v+: 3572, W 3573, W 3575 The original filing was made in December, 1978, and -16- as a result of • • • • • • • • • • • the f: ells and changing the dEsiynated ;:se from irri atian tc ..�nicical and domestic. • • • • • • • • • • • IS 4 J�FIOE ASI'EF. CD. ;-.ADE. !1611 CH; rENNI OF FiCE ERIVE C.4E'F NNE w'1 4'NG E2D01 G'_ENwO::: FILE F PO2 '.266 ;LEvwDOE' c:,.;vimS CO." AOC'1601 SAN LL"S , ALL Er OFFICE A C 6Cz i40 ALL 4:.,SA CO_LPADO 61101 STEc4-;;A- OFFICE P C FOX 5220 STEA49OAT VILLAGE COLO5ADO Fr490 VJ =TIGHT WA -i ER ENGINEERS, INC. E'.3!tv,=ER:Nu C)t':SU_TANTS =Y_ Q_t:,'EF G_7'%-..�+j ' 211 (333, Glenwood Springs Tel. 945-7755 October 17, 1979 Duncan Sinnock Foster Petroleum Corporation P.O. Box 698 Carbondale, CO 81623 RE: Lake Springs Ranch Fater Supply Dear Duncan: r: - c v-5.IGHT + 4 -.: ♦N -,N501.4 ..F SASE - - . iTEE ,t w4YER :A-- -:NS R,;AE GER F.OVE, STORES CAO. E vi'3OERT This letter outlines our recommendations for developing a water supply for Foster Petroleum's Lake Springs Ranch Development. One of the purposes of the letter is to define the facts supporting the plan of augmentation (W-3571) which is currently before the Division 5 Water Court. The current P.U.D. application is for 210 single family units (or their equivalent) plus a 4 acre school site that will all be served by a central water system. The P.U.D. application states that all units will be on a central waste water collection and treatment system which will eventually be annexed by the proposed Spring Valley Sanitation District. WATER REQUIREMENTS The proposed development will have a maximum of 220 EQR (equivalent residential units). This estimate includes 10 EQR for the 4 acre school site. It is assumed that each EQR will have an average of 3.5 people requiring 100 gallons per person per day for in-house use. In addition, the central water supply system will provide enough water to irricate 1500 square feet for each EQR. Lawn irrigation requirements for the development were calculated (Jensen-Haise method) to be 1.5 acre feet per acre for consumptive use. Assu-- ing a 60 irritation efficiency, the irrigation requirement will be 2.5 acre feet per acre. Present plans call for all of the subdivision's waste water to -be treated by the Spring Valley Sanitation District at facilities located at the present Colorado Mountain College treatment facilities. Treatment is expected to be by an activated sludge process with effluent from the facilities being applied on land that drains to Cattle Creek. Total consumptive use of the in-house water is estimated to be 70`. The remaining 30 is expected to eventually reach Cattle Creek and the Roaring Fork River. -17- • • • • • • • • • • Duncan Sinnock -2- October 17, 1979 Annual water requirements for the central water supply system for full development are estimated as follows: Domestic (220 units) Irritation (7.6 acres) TOTAL WATER SUPPLY TOTAL REQUIREMENTS (Ac Ft) 86.2 19.0 105.2 DEPLETIONS TO SPRING VALLEY (AF) 86.2 11.4 97 6 1.'ater for the central water supply system will wells located within the subdivision and drilled int The wells are defined as follows: DEPLETIONS TO ROARING FORK RIVER (AF) 60. 3 11.4 71.7 orae from two or three the Spring Valley aquifer. LOCATION WELL STATE ENGINEER'S Section 33 EX°:CTED PROPOSED DESIGNATION PERMIT NUBER TES, R88W YIE_D DEPTH A 24099F SWs NWL 200 gpm 200 feet B 24100F. NW--, SW4 200 gpm 200 feet C 24101F NWl SWC 200 gpm 200 feet in addition to the central :water supply system, some lands may be irricE:•_ using these wells and springs. The total land irria ted in the P.U.D. is to be less than 40 acres. Water rights for this sup lemental irrigation (acre -:,:e in excess of that defined under the central system) gill be the ranch's junior riohts shown in Table 1. VAN CLEVE WATER RIGHTS Foster Petroleum owns the following irrigation water riohts which have been used to irrigate portions of the Lake Sprines Ranch. NAME OF DITCH AMOUNT Van Cleve No. 1 1.4 cfs Van Cleve No. 2 .9 Van Cleve No. 2 2.0 APPROPRIATION DATE 9-05-1882 9-15-1882 5-15-1884 -18- ADJUDICATION DATE 5-11-1889 5-11-1889 4-18-1390 • Duncan Sinnock October 17, 1979 These rights derive their supply from the Quiale • estimate to yield from a low of 300 acre feet per yea acre feet per year. • • • • • • • -3- ' Spring which we r to more than 1000 According to James Quigley, there have been 35 acres irritated under the Van Cleve No. 1 and an additional 35 acres under the Van Cleve No. 2. The State Engineer's office reported a minimum irrigated acreage under both ditches of 120 acres. Previewing aerial photography of the area, Wright Water Engineers concluded a maximum irritable acreage under both ditches equals a total of 120 acres. According to Mr. Quigley, all of the v,ater available from the spring was diverted during the irrigation season to one or the other of the Van Cleve Ditches. Minimum diversion for a 180 day irrigation season would be 180 acre feet. Assuming 40`; of this diversion was consumptively used, then the historic consumptive use would be 72 acre feet. This minimum of 72 acre feet of historic cor.surr the proposed consumptive use from the Lake Springs Ra system. WATER RIGHTS FOR LAKE SPRINGS RANCH ptive use is more than nch central water supply Table 1 presents the water rivhts that will be used by the Lake Springs Ranch development. WATER COURT CASE NO. NAME W-3571 W- 3572 W- 3573 W-3574 W- 3997 W- 3608 TABLE 1 LAKE SPRINGS RANCH WATER RIGHTS APPROPRIATION ADJUDICATION A"IOUNT DATE , DATE Augmentation Plan Lake Springs Ranch Spring 200 gpm-9-77 Ranch Well A 200 gpm 9-9-77 Ranch Well B 200 gpm 9-9-77 Ranch Well C 200 gam 9-9-77 Quigley Spring .5 cfs 1931 -199- 1977 1977 Duncan Sinnock October 17, 1979 -4- The aucmEntation plan (W -35j1) is the backbone of the doTestic water supply. This plan transfers the senior Van Cleve water right to the central system. The historic annual consumptive use of the'Van Cleve water rights exceeds the future consumptive use of the central wtiter system. Depletion to the Spring Valley aquifer may exceed the historic depletion by the Van Cleve richt - this is due to the ''exportation" of waste water to the Cattle Creek system. This new depletion, which may be es high es 26 acre feet per year, will, in our opinion, not injure any existing vested water right in the Spring Valley area including all of the existing Colorado Mountain College water rights. Supplemental irrication water from the rights, other than the augmenta- tion plan, will cause additional depletion to the Spring Valley aquifer. The exercise of the junior rights will deplete the flow in the Roaring Fork and the Colorado River systems. These depletions will not injure other vested rights on these rivers until some time in the future when numerous conditional and new water rights are put to use. When that time comes, we recommend that the Lake Springs Ranch depletions be covered by releases from Reudi Reservoir or other augmentation sources. Foster Petroleum has already requested aug- mentation water from the Basalt Fater Conservancy ervancy Oistrict. Even if the junior rights were called out, it is our opinion that the transferred senior Van Cleve rights would provide an adequate "lecal" water right for the•subdivision. t r The junior riahts may deplete the Spring Valley aquifer. The-.aximum new depletion is not likely to be greater than 100 acre feet annually. It is our opinion that if this 100 acre feet of new dep etion does occur under water rights W-3572, W-3573, \,'-574, W-3608 and W-3997, that there will be no injury to the existing decreed water riahts diverting water from the Spring Valley aquifer. If you have any questions, please don't hesitate to contact us. Very truly yours, WRIGHT WATER ENGINEERS, INC. WLL:ep cc: Scott Balcomb ,Ron Liston_ 741-22 ay L47 -(J,7 , :o Wi 1 l i am L. Lorah -19a- A SP!N OgEICE F C P C= t:/t/ ASPEN COECkw0C 81611 CHEYENNE OFFICE 3:26 LOCUS, DRIVE ChEYENNt w'YCIAING 82001 GLENwOOD So RINGS OFFICE PC 806 ;286 GLENw000 SPR'!NGS. COLORADO 81601 57EAN.80A1 OFFICE P O 601 5720 STE....8OAT vttLAGE. COLORADO O 499 WRIGHT WATER ENGINEERS, INC. ENGINEERING CONSULTANTS 24200 ALCOTT STREET DENVER, COL ORADC EtC211 1303!4EF-6201 Duncan Sinnock Foster Petroleum Box 698 Carbondale, CO 81623 Dear Mr. Sinnock: Glenwood Springs Tel. 945-7755 April 2, 1979 RtNNFTH R w'RIGHI wItt1Mt L LOpAH RUSSELL t DAPP tICHwVD D /7HNS0N 1. CRAIG GREEN H RAY Ntw*AYEP PAARIITN PA S1 O1ES RALPH L 1OREN FRANK J ft!L4ASI RE: Lake Springs Ranch Water Rights According to Ron Liston the revised Lake Springs development will provide central sewer collection and treatment facilities for the equivalent of 195 single family residences. Current plans envision the expansion of the existing CMC waste water treatment facility to serve CMC, Lake Sprinas Ranch and Los Amigos. Wright -McLaughlin Engineers is in the process of developing a service plan for the area's waste water treatment needs. Previous water supply plans for Lake Springs Ranh (see our letter of December 20, 1978) assured the development would b served with individual septic tank/leach field systems. That platy assumed that about 25% of the inhouse domestic water would be cons Iptively used. The revised plan to use the CMC plant would mean that the inhouse domestic water requirement of 77 acre feet per year would be a total depletion from the Spring Valley area since the return flow from the sewage treatment plant would not be to Spring valley. It is our opinion that the water rights applications currently before the water court, when approved, will provide sufficient water to meet water requirements for the subdivision without injuring other vested water rights in the Spring Valley area. WLL:ep 741-22 Very truly yours, WRIGHT WATER ENGINEER$, INC. �C / BY �� ��!' r,, ? William L. Lorah -20- • • • • • • • W.'.STEWATER SYSTEM Lake Springs Ranch will be incorporated into the Spring Valley Sani- tation District which is now in the process of being formed. The purpose of the District is to provide wastewater treatment for Colo- rado Mountain College (CMC), Los Amigos PUD and Lake Springs Ranch PUD. The proposed treatment site, as shown on the foliowi,ng vacinity map, will be at the existing CMC treatment site. The existing CMC treatment facilities will be upgraded and expanded to meet all applicable dis- charge requirements and will be sized to meet all future requirements of the areas referenced above. To date, an agreement has been reached between CMC and Los Amigos PUD to incorporate the existing treatment site into the Sanitation District and agreement in principal for the formation of the District. Lake Springs Ranch PUD has not been a party to that agreement because of the fact that their position in the subdivision process did not allow them to participate without restrictive conditions. As shown in the Spring Valley Sanitation District Servide Plan, prepared for the formation of the District and on file in the. County Planner's office, the facilities are being designed in anticipation of the inclusion of the Lake Springs Ranch PUD into the District. The Service Pian is based on a total buiido.:t of 210 dwelling units • at 3.5 capita/unit and 100 gallons per capita per day. The wastewater collection system on site is as proposed on the Water and Sewer Utility Pian and the Sewer Plan and Profile sheets. All collection lines will • • • • • • be 8" diameter laid at a minimum slope of �3.4;; or g lection system will require a lift station to servi area. Additionally, Lots 1, 2, 11, and 12, and pos eater. The tol- e the 1'anCl eave Road ibly Lot 13, Block 2 cannot be serviced by gravity sewer. It is propos() to service these lots by (1) installing an in-house grinder type puri) to pump directly to the force vain or (2) installing a conventional home submersible sewage sump pump, following a septic tank for solids removal, and pumping to the force rain. The individual lot owner would have the option of the col- lection facility to he used. Off-site sewer from the PUD boundary to the areatr,ent facility wi l i be gravity sewer. The sewer will run approximately parallel to County • Road 114 and will actually connect to the treatment the CMC or Los Amigos collection systems. These two beinc analyzed on an engineering feasibility and cos • with the two entities now that the Sani_ai.ton Distri being formed. In either case, no rift station will off-site sewer system. • • • • facility through either alternatives are t -effective basis ct i s , in fact, be required in the • • ft- STATES _ '1';=-- ;NE INTERIOR OLOGICA L SURVEY E / 7,I2 GET DOC S` -'F -'r. -G_ E c Mi /•. / — tP ( ; E S?= I r, c`0''' It L ;•_ _ M 1 CD 2- 7.3:y - 7i If 2 7 4 4143 ft crF\ \ o _� r/ 'J \ Esc �! ,',1�/ ("7,6e.'/ .\ _ �� /...-, \moi' /� Lim ^� i,, --Z. •1 f • • NA cma=y- / ` c \\\T---:.. . f,= zccc' • • • • S\SERGRDUND UTILITIES The three concerned utili. ca7,2ar s -- Rocky Soy tain Natural Gas, «=i} Cross Electric Association, and Mcsntain Cell ere sent Prelimin- ary Plat site plans on June 11, 1979, in a.der to afford all parties pportJn't to ciscuss %he pre/ect at the UtiliLty Coordinating Co mittee meeting Cr Jade 21, 1979. As of that :eeti only Xountain Eel] has had an opport;Gid to forra1ize any ccGstructi n requirements. They • have indicated that the Ki]i req:ire a 5' rich; I-way on all lot lines fronting p:biic rcaiays. • • Rocky Mountain Natural Sas as indicated icfcr ally that they can pro- vide services by extending biseributon lines fro, the approximate vicinity of CMC. They have not indicated tKalr ea cent requirements within the PUD. Holy Cross Electric has as vet no (formulated any require- ments. equi -ments. It is anticipated that beth utilit companies will indicate easement requirements during the for -nal Prelimi ary Plat review period. one 40 • of the utilities expressed anyforeseeable difficuities in servicing the PUD during discussion at the Utility Cocrdinati 41 • • g Committee. • • • • • • • • • • • APPENDIX A ENGINEERING GEOLOGY AND PRELIMINARY SUBSOIL INVESTIGATION RICHARD D. LAMM GOVERNOR s • • • KA xPkCI) srr�_� •i�� 4.. Leo COLORADO GEOLOGICAL SURVEY DEPARTMENT OF NATURAL RESOURCES 715 STATE CENTENNIAL BUILDING — 1313 SHERMAN STRE T DENVER, COLORADO 80203 PHONE (303) 839-2611 February 3, 1978 Mr. Robert Witkowski Garfield County Planning 2014 Blake Avenue Glenwood Springs, Colorado 81601 Dear Mr._Witkowski: RE: LAKE SPRINGS SUBDIVISION NCH We have reviewed the Chen and Associates Report on t is subdivision (Job No. 14285A Jan. 30, 1978) and find that it has dequately addressed the geology and soils of the site. It appears that the geologic constraints of the site are minimal but that soil conditions are such that individual site specific soil investigations and tests should be required before building permits are issued. With the possiblity of both swelling soils and/or soils that can compress under load when wet being present, this will be very important to assure the long term stability of the structures. If these tests are required, we would have no objection to approval of this proposed subdivision. LRL/vt cc: Land Use Commission Sincerely, _, //// L. R. Ladwig Engineering Geologist • GEOLOGY JOHN W. ROLD Director 6 chen and associates, inc. CONSULTING ENGINEERS SOIL & FOUNDATION 96 S. ZUNI • DENVER, COLORADO 80223 303/744-7105 ENGINEERING 1924 EAST FIRST STREET • CASPER, WYOMING 82601 • 307/234-2126 ENGINEERING GEOLOGY AND PRELIMINARY SUBSOIL INVESTIGATION FOR PROPOSED LAKE SPRINGS RANCH SUBDIVISI�ON SECTIONS 32, 33 AND 34, TOWNSHIP 6 SOUTH AND SECTION 4, TOWNSHIP 7 SOUTH, RANGE 88 WEST GARFIELD COUNTY, COLORADO Prepared for: SCARROW & WALKER, INC. P. 0. BOX 460 GLENW00D SPRINGS, COLORADO 81601 Job No. 14,285A January 30, 1978 • • TABLE OF CONTENTS CONCLUSIONS 1 SCOPE 2 PROPOSED DEVELOPMENT 2 SITE CONDITIONS 3 GEOLOGICAL CONDITIONS 3 Bedrock Conditions 4 Soil Conditions 4 Structural Geolo3y 4 SUBSOIL CONDITIONS 5 GEOLOGIC HAZARDS 6 MINERAL RESOURCES 7 FOUNDATION TYPES 7 SITE GRADING 8 ADDITIONAL INVESTIGATION 8 FIG. 1 - LOCATION OF TEST HOLES AND PITS AND SURFICIAL GEOLOGY MAP FIG. 2 - LOGS OF TEST PITS FIGS. 3 through 6 - SWELL -CONSOLIDATION TEST RESULTS FIG. 7 - GRADATION TEST RESULTS TABLE 1 - SUMMARY OF LABORATORY TEST RESULTS CONCLUSIONS (1) The proposed subdivision development is feasible from an engineer- ing geology and subsoil point of view. (2) There are no geologic hazards nor commercial mineral deposits (3) which would render the project unsafe, infeasible or undesirable. Foundation types in Block 1 should consist of pay and grade beam construction as recommended in our original report (Job No. 14,285 dated April 6, 1977). Spread footing foundations occasionally utilizing minimum dead load pressures are generally suitable for residences and duplex residential buildings over the remainder of the site. (4) Additional investigation by subsoil exploration or foundation excavation inspections should be performed in Blocks 3, 4 and 5 to better define subsoil and bedrock conditions and determine proper foundation design parameters at specific building sites. 2 SCOPE This report presents the raeuits of an engineering geology and preliminary subsoil investigation for the proposed Lake Springs Ranch Subdivision situated in Sections 32, 33 and 34, T. 6S. and Section 4, T. 7S., R. 88W., Garfield County, Colorado. The report also presents the most probable type building foundations, recommended soil pressure ranges, engineering geologic aspects of the site, general subsoil con- ditions, and other preliminary design information suitable for general planning. The investigation included a field geologic survey and exploration pits. We previously conducted a soil and foundation investigation for Blocks 1 and 2 of the subject subdivision and reported our results under Job No. 14,285 dated April 6, 1977. The results of that investigation and a review of pertinent geological literature were aiiso a part of this investigation. Results of additional percolation test under our Job No. 15,346 dated October 19, 1977. were reported PROPOSED DEVELOPMENT We understand that the proposed Lake Springs Ranch Subdivision will have approximately 55 lots designated for single-family residences and 7 lots with planned duplex units. It is proposed to supply water from a community water system utilizing wells as the water source. individual sewage disposal systems are planned for thelsingle-family residential lots. 3 SITE CONDITIONS The Lake Springs Ranch Subdivision as presently platted includes an area of approximately 441.7 acres. The topography at the site is comprised mainly of hilly ridge and valley relief with several scattered knobs or topographically high points occurring along the western portion of the site. The ground surface at the site ranges from Elevation 6890 to 7310 feet above mean sea level. Spring Valley occupies approximately one-quarter of the proposed subdivision on its western end. It forms the low area of elevation within the site. The stream Spring Valley originates immediately upstream of a sma south-central portion of the site and flows generally i which flows in 1 pond in the orthwesterly. The remaining drainages are intermittent and show no i�ldication of recent erosion signifying that they during periods of heavy local rain. building area to the west of Spring Valley is of gentl sloping (2`6 to 11%) ground falling toward the drainage portion of the site to the east and southeast of Sprin upward from the valley at gentle (5%) to very steep (3 slope in all directions but which generally drain towa carry very little surface water only The relatively small proposed to moderately The much larger Valley slopes %) slopes which d Spring Valley. At the time of our geologic survey and latest sullsoil investigation, the ground surface was covered with 1 to 2 feet of snow. The vegetation which could be observed was scrub oak and sagebrush. GEOLOGICAL CONDITIONS Spring Valley is an upland plateau valley that has been incised w Into Pleistocene age basalt lava flows which cover a 1 rge upland area in this region. The site of the proposed Lake Sprin-j!; Ranch Subdivision extends from Spring Valley on its western end into the hilly terrain to the east of the valley. Bedrock Conditions: The only bedrock exposed on the site consists of scattered outcrops of the Pleistocene age basalt flows. These outcrops are confined to relatively small areas near the tops of the scattered knob features and along one ridge and one road cut which is immediately outside of the subdivision boundary. The Pennsylvanialn to Permian age Maroon formation directly underlies the basalt flows a the Quaternary soils at the site. nd a portion of The basalt at the site generally consists of highly fractured blocks of extremely hard, competent rock. The joints are filled with clay. Occasionally large amounts of volcanic ash which is composed of silt are present within the bedrock. Soil Conditions: The Quaternary soils present at the site consist fro generally of residual and colluvial (slope wash) clay • with cobbles and boulders on the upper hilly terrain a gentler slopes along Spring Valley. pnd silty gravel d clay on the Some alluvial soil deposits may be associated with the lower ground elevations along Spri g Valley No subsoil investigation was performed along the Spring Vlley flood plain, and the composition of soils in that area are not know rA by us. Fig. 1 presents a surficial geologic map for the proposed Lak Springs Ranch Subdivision. Structural Geology: Since no outcrops of the Maroon formation were observed at the site, the bedding attitude is not known. However, about 2 miles west of the site, the Maroon formation is dipping generally to the northeast This dip probably continues in a northeast direction at the site but may be gentler than that to the west. A Pleistocene fault is present in the basalt flow west of Spring Valley. This fault should not have any affect on the proposed development. SUBSOIL CONDITIONS From the exploratory holes drilled for the subscil investigation of Lots 1 and 2 and the test pits excavated over the remainder of the site, it was found that the subsoil conditions range from fairly uniform to erratic across the site. Generally, the soils consist of medium stiff to very stiff, sandy clay with some scattered lenses of clayey gravel at the lower elevations of the site and silty gravel, clay, gravelly clay and some silt in the upper elevations ofthe site generally northeast test pits are shown on Fig. 2. The of County Road 119 and east of County Road 1114. The logs of clay and sandy clay range from 1 to more than 20 feet in depth 0,11 beneath the surface. Sone clay also exists below the silty gravel strata. As stated in our original report and as shown 'by the results of swell -consolidation tests presented on Figs. 3 through 6, the clay is very erratic, some which possess a moderate swell potential and some porous zones which will consolidate moderately when wetted and loaded. The silty gravel is present at about 1 to 5 feet deep and varies from on the order of 4 to 8 feet thick. The gravel soils contain cobbles and boulders which are generally angular to subangular; volcanic • ash which is gravel soils general will 6 predominantly a silt r aerial; and some clay. Some of the will consolidate moderately when wetted and loaded but in not consolidate as much as the more porous Bedrock was encountered in Pits' 2 and 3 at 2 to consisted of very fractured basalt. No percolation tests were performed as a part o clay. 5 feet deep and this preliminary investigation on the remainder of the site exclusive f Blocks 1 and 2. The clay soils over the remainder of the site will hae fairly similar percolation properties as those In Blocks 1 and 2 whit gravels will possess faster percolation rates. No free water was encountered in the test holes drilling nor in the backhoe pits at the time of excava Samples of the soils were analyzed for water sol The soils have negligible (less than 0.1,;) sulfate con cement types should generally not be required in the c deterioration. e the lower silty at the time of tion. ubie sulfates. tent. Special ncrete to resist GEOLOGIC HAZARDS No conditions were observed at the site which w7ld constitute a geologic hazard. We understand that the common area along the Spring Valley stream and the pond at the. upper end of the stream are not designated for construction sites. These areas will probably be he only areas that will require construction restraints. No other p oblems associated with the site geology are anticipated provided that th recommendations for foundations and site grading discussed in this rep rt are followed. o MINERAL RESOURCES It is our opinion there are no commercial mineral deposits as defined In the Colorado Open Mining Land Reclamation Act at the site which would be of significant economic or strategic value. FOUNDATION TYPES The foundation types for residences constructed in Blocks 1 and 2 are covered under the Foundation Recommendations section of our original report (Job No. 14,285 dated April 6, 1977) and consist generally of pad and grade beam foundations for Block 1 and spread foot types in Block 2. In general, the foundation types In. should consist of moderately loaded spread footings. soil pressures for the upper 1,000 to 3,000 ings for foundation Blocks 3, 4 and 5 laximun aliowable sandy clay soils will be on the order of psf while maximum soil pressures for the silty gravel will range from 2,000 to 4,000 psf. Sone foundations stiffer clays may require mintm40 dead load pressures n the denser, iso. Spread for higher footing foundations on the bedrock generally may be designed bearing pressures. Because of the very erratic nature of the subsol s with respect to their occurrence and physical properties, individual building sites should have specific subsoil investigations or the foundation excavation IP should be inspected in order to determine the proper foundation design requirements for the specific structures. • • • SITE GRADING Where roads and building sites are constructed within the site, it should be feasible to construct permanent cut and fill', Slopes up to 20 feet high at inclinations not exceeding 2:1 These slopes should be stable if vegetated and care is surface water from penetrating the slope faces and the horizontal to vertical. used to prevent subsoils immediately above the faces. Cut or fill slopes greater than 20 feet high should have stability studies performed as a part of the slope design prior to construction. Temporary excavations in the on-site soils should be stable at an inclination of no steeper than 1:1 if well drained. These steeper temporary slopes will slough If exposed to the atmospheric elements for several days. The majority of the on-site soils are suitable for use in compacted fill with the exception of cobbles larger than 8 inches. Roadway fill should be compacted to at- least 95% standard Proctor density at optimum moisture content and should be placed in lifts to achi' compaction. Fills should not block drainages. Excavation in the clays and the majority of the be done with conventional excavating equipment. Some gravels and the majority of the bedrock will probably eve uniform silty gravels can of the denser require light to moderate blasting to excavate, especially in utility trenches and other .r 0 confined excavations. • • ADDITIONAL INVESTIGATION This report is preliminary and suitable for general design and planning. Based on our present knowledge of the site geology, we do not anticipate any unusual problems from a geotechnical viewpoint. Because of the erratic characteristics of the upper soils with respect to their occurrence, swell potential and compression characteristics, we recommend that a more in-depth investigation for Blocks 3, 4 and',5 or excavation inspections be performed in order to determine specific design criteria for individual building foundations. Individual sewag disposal systems should include percolation test data as a part of their design. r MJP/bn • CHEN AND ASSOCIATES,IINC. By Reviewed By -n IF o o �� m� n� ~r / ^ -.•••=~__ cat /_ '`.� / ``-' -- -'--7 ~< _ / -`~` ` / ` �- '" .---/-- / '-' ',/ / m ,"). /_==�Y,»n\ - /// `/ /-^/``»"'_-`\ v \ . \ `, ' 64' � n 0 / ' y r/ / / / \� / . / ' �- / `-_-- / ` '- `� / \ -'--- / _~' MI_ \ / ` -----/- `^ / / ,' _-� ` 1 - ` -`'_ � / / ,' (--}^ �- �-- --`` �- -<----\ ,9- I: /' -_'/'--_� �/ ', `` / } ' \/ ,~ mm � / n LI ( ----'-- / / ' `\ ' / ���_� /'\ / ' / `` ' / - - / / Co ' Test pits excavated on January � _ .� m 0 r O n 1'I 1111'1 f 1 1 T 1 V• '1'I fJ • \ \ \ \ \ \ N. \ • \ \ • \ \ \ \ \ \ • \ \ \ \ \ \ \ \ \ \ L \ \ \ \ \,� -o r I 0 II 1- 1 0 11 - W O N) . co II - (X)• ),A.) • O li<(a ((((((((((c��i(�r((< ((to Y (u( (u N 'e\O. AS�CC�CSS>�• v v v v v v 'ilium/Ili (t�(i(t((( \ \ D r I z - r N (7 11 II 0 II 1 ^ II VI V V1 O CO V C7 II II U 0 0 0. . • t \ \ \ II OJ pa o • Sri o _ n ° . • t2•' Y1 •. C") r) k..1 1 \ \ \ \ _\ \ \ \ \ \ \ \ 1.-; O (7 I I 11 O • 1. 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" -• (D G Cr - - f, ('J 00 to n t ;Da rt < 7 `G rt 0 -. n 0 < (t -•< v, 7 -1 rt 2n -• 7 lD a �< k - 7 r, (D l 7. ▪ _ rJO2(0 (D0 -0-•cr- Ni_a 0 r -t '� ,.>. -- a - - •,r - to rt -I '< v, a, -• 0 c u < 000 p Esc 7 (D CL -1 0 n v ,--_- (i O r -t -- 0 -, ...-' S ut L- 0 - . i r -r -r, J r1: Ui (D rt lfl 7 rt rt `< (L X - r. : - -rl 0) -h (D rr 7 o ,, 2 I < rt 1 C - 0) j - c -• (D n - (D n (0a - n Qto - - n• n r. o (J t1:_ ,- . - 1 o 7 c 0; -• a 3 rt da 0 Compression Compression - 2 3 0 2 6 10 12 CHEN AND ASSOCIATES 0.1 PPLIED PRESSURE - kat' Natural Dry Unit Weight pCf Natural Moisture Content - 11.9 porcent I + Adc tiOna1 i 1 c.rt.:lression inde con st< �� -- • u -q due to O tt 170. 1p • Typical sample of s,i1:y Typ cal sample 1 of sipty clay from fitl ati depth 1. 0.1 PPLIED PRESSURE - kat' 01 #14 28SA I o 10 APPLIED PRESSURE - kef Swell -Consolidation Test Results 100 Ficir. 3 Natural Dry Unit Weight - 90.6 pcf Natural Mo t!u f Content - 20.0 percenr I + Adc tiOna1 i 1 c.rt.:lression inde con st< �� -- pras u -q due to O tt 170. Typical sample of s,i1:y clay fron Plt 1 a tcbth 6.S` 01 #14 28SA I o 10 APPLIED PRESSURE - kef Swell -Consolidation Test Results 100 Ficir. 3 Compression Compression - 1 2 1 2 3 • 4 5 6 1 8 9 0.l CHEN AND ASSOCIATES 0.1 APPLIED PRESSURE — k•f Natural Dry Unit Weight o 106.6 pct Natural Moisture Content 11.9 percent Expansion nder jcompt constart pressure under constant •♦. p weft ng. to vett inky. • 4) 0 ' Typical sample Typical sndy sanp'e it 4 a of silty clay from Pi: a cepth 3'-0" 0.1 APPLIED PRESSURE — k•f #14,285A 10 0 io APPLIED PRESSURE - kef Swell -Consolidation Test Results 100 Natural Dry Unit Weight .. pcf Natural Moisture Content - 11.e percent Additignal jcompt ssion under constant �--- --L prielssure due to vett inky. ' Typical sample of sndy sil: from it 4 a pth 3'-0" #14,285A 10 0 io APPLIED PRESSURE - kef Swell -Consolidation Test Results 100 • to Compression Compression - % - Expansion 0 2 3 4 5 6 7 8 0 1 2 3 4 5 #14,285A CHEN AND ASSOCIATES 0.1 PPLIED PRESSURE — kef Natural Ory Unit *eight = 110.1 pct Natural Moisture Content = 10.8 percent Natural Dry Unit Weight - pcf Natural Moisture Content - 18.5 percent • Exp.nso nder i constant pressure ,�i-1 uee Additional coup ssion wider constant • {i `b presiure ale to wetting. P • {, Typical sarrple of silty, sandy 5ra'e1 ty clay from 1 frck 1 5 at depth 5'-0' 3'r0" l 0.1 PPLIED PRESSURE — kef 0.1 10 10 APPLIED PRESSURE — kalif Swell -Consolidation Tx.st Results 100 Fig. Natural Ory Unit *eight = 110.1 pct Natural Moisture Content = 10.8 percent • Exp.nso nder i constant pressure ,�i-1 uee retlting. • {i P {, Typical , sanpl _ Df si ty clay from 1 Pit 1 1 6 ! at 11111 depth 3'r0" l , 0.1 10 10 APPLIED PRESSURE — kalif Swell -Consolidation Tx.st Results 100 Fig. i• • • o`P 0 Compression Compression - % 1 2 3 4 5 0 2 3 4 #14,285A CHEN AND ASSOCIATES 00 APPLIED PRESSURE — Natural Dry Unit Weight • 74.6 pcf Natural Moisture Content • 12.5 percent Notu 01 Dry Unit Weight • 100.7 pcf Notu a1 Moisture Content . 11 .1 percent 11 11 0 11 1 1 T "111111111111 � • p e..Ssfnt uw- o PJC rJeit nt upon w tt Ina. lir 1 eer• • 1E11 w NO II 11 11 0 1 ' a Typi•a n; ie o si 'y, san y g av II 1 Pit i� 6 at dept 5 -0' IN 00 APPLIED PRESSURE — APPLIED PRESSURE — kaf Swell -Consolidation Test Results 100 Flue 6 Notu 01 Dry Unit Weight • 100.7 pcf Notu a1 Moisture Content . 11 .1 percent 1 1 T � PJC rJeit nt upon w tt Ina. • 1 ' a Typical sarrple pf s ty cia from Pit t pti d pth 10'-0" a1 APPLIED PRESSURE — kaf Swell -Consolidation Test Results 100 Flue 6 1 0 CHEN AND ASSOCIATES Consulting Soil and Foundation Engineers t MVORQM TER ANALYSIS bi� SIEVE_ ANALYSIS (max TIN AEAOINOS �MlA 90r Oars 4 O IMw •100 11 u S sT►ND►RD •ERit$s, •,00 •50 .40. 30 •N 'ti •• CLE►R 30u►RE OPENIg$ b' ►y' M' 3' s'a' IMO= �— • IMO M —M ; • S _ - I _ _ ammo __ • = I��s�•�••�i��—�•��1••�• + ND ___ �• 911.1.1.1.11 •, 4--- is 01111000 aaaaaat♦aRt♦aM011111/M st♦M S M sleimii011. nil= 01111111101141= —���� =� �• -1 ri00 M rM� Mfg i� -M�9—= �_� GM !M�•ommiNis_millrss•M�M3M1191i—� -� -+--- OM M M a� i IMIE11019 __O M�� M•MM•iM Mr i M +- — M —�I--- unselemsanniimmil Mtn .4_4___ —_aommor_.aauma4_ l•M M —M•� — =�=• _ v ���a= i� 111111M1110111 — _9-�Risfa 11111111011=1 �A ii -�=M 1111M, f ��i M Om silimmis i� M•MM• = _ =MUM ��r���•M �•M alli := sM •i��•1�_• M•NMI M•a�i� -__4. =__�i_ Ms••� —moi• ��•�! 4 mos Y 3 •M i f—� M• �— �- � �� MINE 1=1•D MIIIP 9�•I��IMMO asimilliM1110•=r= NSM - aiiiiiiiiiiiiiii __ - 1 �•� INEMBE - — t__. --. KINMeV �•�� = _ NMI 100 —Emmons. i� I� = R! i — --S + - - ---- at••MB MB _- a��91 �•�91=1919 011111110110 MIN —_— lallM=EWSIIWW.. I y. aliVC um �i�•� NMI �M_ ; 1�•i��i .. - =Ira 4111111100•111111 imam MIND MI 4 1521 I= �sj _ _ _ a so �M • - I OOt009 09 037 0 4 .49 t97 990 s A34 •4 Ass �9• 3�� 1a1 If7 DIAMETER Of PAR I LE IN MILLI ETEAS ,y ? —r �-7— r�-_--T — t 009 006 009 0 9 037 T 74 149 197 t 990 a '�39 • is 1 9I 9I 3a i 791 .fl DIAMETER Of PARIGLE IN MILL METERS IM 1 CLAY (PLASTIC) TO SILT IMO•!-PLAS71CI r1RE I Y[0iu1 LOA'S!' rlct[ l•.-�-�►7isE iCOBBLES GRAVEL 60 % LIQUID LIMIT SAMPLE SAND 28 or Slightly silty, sandy gravel SILT AND CLAY PLASTICITY INDEX FROM 12 % NP %s Pit 2 at depth 2' - 4}I MYDROM'TER ANALYSIS SIEVE ANALYSIS 7NR I' 0104 is mil so sew •WM Iru4 u S STANDARD 11E111ES9,0 T C.EAR SOu&RE OPENIN011 •.00 •so•'0•so •w '4 •4 ►,• 3.. , 3. rr �— ; • S _ - I _ _ __ = + ND liiii •, 4--- is =sem== aaaaaat♦aRt♦aM011111/M st♦M M sleimii011. nil= 01111111101141= -1 Mb i� -M�9—= -� -+--- OM M ���•� — �M•�iMsiM i IMIE11019 4-} 111110111.•M Mr i M +- — I— .4_4___ M r i� — _ v i� 111111M1110111 — �M (1=111111010 11111111011=1 f M silimmis _ �•M alli := -__4. M Ms••� s— 4 Y 3 t•Mmom • i MINE 9�•I��IMMO asimilliM1110•=r= I•MO__�=M� - 1 moms -_i •M 100 aliVC um �i�•� �M_ ; 1�•i��i .. 4111111100•111111 imam simiiiimusimiwis0410 maii196 —M�• I= �sj _ _ _ - __ IEMM��•M•MM•M�• • - I OOt009 09 037 0 4 .49 t97 990 s A34 •4 Ass �9• 3�� 1a1 If7 DIAMETER Of PAR I LE IN MILLI ETEAS ,y 1 10 • !6 • 6 1 • V • S CLAY (PLasnc) TO SILT (MOM -PLASTIC) E I D Q 0-06scc1 GRAVEL LI SAM 014 .7i1cA GLAD LIMIT PLE Of SAND % SILT AND CLAY PLASTICITY INDEX GRADATION TEST RESULTS /O 0 SO 60 00 0 60 60 60 100 Job No. 74285A LN 1J N W F- W 1- >- cr 0 1- 4 0 4 J 0 S4 N >. ro U ?• - V) >. OD u > .- V) 1 >•• CO 0 >• -• V) Silty, sandy gravel 1 � ) '0 u V) 1 (p (0 CO T a.) --40 w_ >� (0 N G) > L G7 > N L a. >. 7:1 C N > V) > (0 L ci ).- ro C CO N40.. > V) > MI > V) Silty, sandy gravel 1 >• CO u' , >. V) PERCENT PASSING , D W N W D V') N O Ol N N N n z n n Li(nto n v WATER ' SOLUBLE i T o O 0 O ATTERBERG LIMITS H x J - v z M Z 1 O o T -1 '.O Q1 c M ' M '.D O -- '.0 ^ 1 — O No 100.7 1 36.4 I NATURAL DRY DENSITY NATURAL MOISTURE (%) Q1 •- .-• O O N N N • .► 00 41 .- CD • .-i • .- to aD .- CO 0 ... LA N ..- r--1'll DEPTH (FEET) ul O ... N O 0 Ll1 Q • tel 0 0 Ll1 r•., 3.0 1 0 Ll1 O. O. F- N F- F- LL 1 t • • • w 0 • • • s • • PREPARED BY WRIGHT WATER ENGINEERS SPRING VALLEY WATER RESOURCES AND WATER RIGHTS MAY, 1977 GLENWOOD SPRINGS • • TABLE OF CONTENTS COVER LETTER TABLE OF CONTENTS SECTION TITLE PAGE INTRODUCTION I- 1 II WATER RESOURCES II- 1 Surface Hydrology II- 1 Groundwater Hydrology II- 4 III WATER RIGHTS III- 1 IV OPPORTUNITIES FOR COOPERATIVE USE OF WATER RESOURCES IV- 1 Reasons for Cooperative Use IV- 1 Water Management Districts IV- 2 V CONCLUSIONS V- 1 BIBLIOGRAPHY FIGURES (In back of report) Figure 1 Spring Valley Basin, Surface Water Resources Map Figure 2 Spring Valley Basin, Grpundwater Resources Map LIST OF TABLES Table 111-1 Decreed Water Rights in Spring Valley Table 111-2 Undecreed Registered Wells III -2 III - 5 • • SPRING VALLEY WATER RESOURCES AND WATER RIGHTS SECTION 1 INTRODUCTION This report is an evaluation of the water resources and water rights in the Spring Valley basin, located about three miles south- east of Glenwood Springs, in Garfield County, Colorado. The report identifies opportunities for development of the water resources in the basin, as well as discussing some potential problems if the water re- sources arenotdeveloped and used in a cooperative and orderly way. The report defines and maps the groundwater (wells) potential in Spring Valley based on existing geologic mapping, well logs, interviews with drillers, field inspection, and review of the State Engineer's Records. The report also estimates the amount of both surface and groundwater in Spring Valley available for use by various types of land use. The report lists the decreed water rights in the Spring Valley area and comments on the historic use of these rights. The material presented in this report is not sufficient "proof" by itself to transfer water rights from irrigation use to domestic and municipal uses. We have, however, made general comments on the overall water resource situation in Spring Valley, including some discussion of management plans for the main aquifer. • 1-2 The Spring Valley basin has a topographic tributary area at the top of Red Canyon of about 11 square miles. From the low valley bottom elevation of 6,600 feet the basin rises to an elevation of 9,400 feet at the northern boundary. Vegetation ranges from hay fields in the valley floor, to scrub oak and sagebrush over most of the basin. A few areas of pinion -juniper are found in the basin, mostly at elevations below 7,000 feet. Some conifer and aspen growth occurs at the higher elevations in the valley. When the first settlers arrived in the early 1880's Spring Valley contained a large natural lake. One of the pioneers, Mr. Forker, drained the lake by cutting a drainage channel through to Red Canyon. Once the lake was drained he began to farm the land. Between 1882 and 1885 • eight ditches were constructed in the Spring Valley area. Most of them • diverted water from Landis Creek, the only major water course in the basin. Around 1909, the only major man-made reservoir was constructed at the headwaters of Landis Creek. Since the early settlement of the basin, springs have been used for domestic and stock water needs. A few of the larger springs have been used to irrigate crops. Less than ten percent of the 11 square mile basin is made up of publicly owned land. Below is an approximate breakdown of the relative ownership in the Spring Valley basin.` -• It should be noted that the water resources in Spring Valley could, and probably would, serve land outside of the topographic basin, e.g. C.M.C. land outside of the basin is now served by wells drilled into the Spring Valley alluvium. • • • 1-3 PERCENT OF OWNER BASIN LAND OWNED Beattie Enterprises 53 Lookout Mountain Ranch 8 Ould 7 Foster Petroleum 6 Cox 4 Nieslanik 3 Colorado Mountain College 3 Powers 2 Kindall 1 Gould 1 Carlson 1 Cabrinha 1 Sunlight Partnership 1 Bureau of Land Management 8 White River Nation Forest 1 According to the present Garfield County Master Plan, Spring valley is presently zoned A/R/RD (Agricultural/Residential/ Rural Density). This designation allows a minimum lot size of 2 acres. According to Bob Witkowski, Garfield County Planner, the maximum density which would be allowed under the Planned Unit Development Ordinance would be 4 units per acre. Allowing for undevelopable areas (such as steep slopes and flood plains) included in gross acreages, this might allow up to 10 units per acre in clustered developments. Zoning changes in Spring Valley will probably occur in response to action by the land owners. • SECTION 11 WATER RESOURCES SURFACE WATER HYDROLOGY The Spring Valley Basin is located about three miles southeast of Glenwood Springs at elevations ranging from 6,600 to 9,400 feet above sea level. Total area of the topographic basin is about 11 square miles. The only major drainage course in Spring Valley is Landis Creek, which drains less than half of the area. The headwaters of Landis Creek are in the northeast of the basin, and begin south of Glenwood Canyon at elevations above 9,000 feet. The Landis Creek drainage then opens to the southwest for about 3 miles, where it enters the low area of Spring SValley. Waters in the low area of Spring Valley flow north and then down Red Canyon for two miles to the confluence with the Roaring Fork River. Little, if any, Landis Creek flow ever reaches Red Canyon. Landis Creek has a total tributary drainage area of 4 square miles. Of this, 0.9 square mile is tributary to Hopkins Reservoir? and 3.8 square miles is tributary to the point where Landis Creek crosses the county road. In Section 15 Landis Creek has a continuous year round base flow fed by springs located above 8,000 feet. This base flow infiltrates the ground before it reaches Spring Valley. Only during the height of spring snowmelt runoff or after heavy rain storms does Landis Creek flow enough to yield surface water to Spring Valley. The amount of precipitation in the Spring Valley area varies with elevation. Higher portions of the basin receive an average of 25-30 inches of precipitation per year, while the lower valley bottom receives 15-20 • • II -2 inches in an average year. More than half of the precipitation falls in the form of snow. Drought years (such as the 1976-77 winter) precipita- tion can be expected to be 30% or less than the normal year's precipitation. Several residents of Spring Valley believe that the area receives considerably less precipitation than the Roaring Fork and Colorado River valleys just a few miles away. Average annual gross open water surface evaporation is estimated to be 32 inches per year. Net lake evaporation would range from 12 to 17 inches in the valley bottom. Total annual precipitation over the 11 square mile basin equals about 16,000 acre feet of water. Most of this is evapotranspired to the atmosphere by vegetation, open water surfaces, and snow sublimation. A small, undetermined portion of the water, perhaps 1% or 2%, percolates deep into the bedrock and eventually reaches streams outside the basin via springs. Stream flowsthat reaches the lower areas of Spring Valley occur only after heavy rainstorms or during the peak of spring snow melt runoff. This flow, along with the flow from various springs in the area, recharge the Spring Valley aquifer (see groundwater section). If the aquifer is "full", the excess will flow down Red Canyon. Calvin Cox, who has lived in Spring Valley since the 1930's, told Wright Water Engineers that water from Spring Valley flows down Red Canyon every spring. The rate of flow is controlled by a ten foot high dam which was reportedly constructed by Garfield County to protect the • county road from high spring flows. • • • 11-3 Using information from Mr. Cox, we have estimated that the average annual flow leaving Spring Valley down Red Canyon is about 400 to 600 acre feet. This spring's spillage down Red Canyon was estimated to be 15 acre feet. When the dam's 36 inch CMP outlet is closed, water can be backed up to a depth of about 7 feet. When the water is 4 feet above the outlet invert, the water will back up about 3,000 feet. At a depth of 7 feet the water is estimated to back up about 5,000 feet. Extreme precipitation for the Spring Valley area has been defined by Federal Weather Agencies (See Bibliography) as follows: FREQUENCY 2 Yr. 5 Yr. 10 Yr. 25 Yr. 50 Yr. 100 Yr. 2 Yr. 5 Yr. 10 Yr. 25 Yr. 50 Yr. 100 Yr. DURATION DEPTH IN INCHES 6 hr. .9 6 hr. 1.2 6 hr. 1.4 6 hr. 1.6 6 hr. 1.8 6 hr. 2.0 24 hr. 1.2 24 hr. 1.6 24 hr. 1.8 24 hr. 2.2 24 hr. 2.4 24 hr. 2.6 • • II -4 GROUNDWATER HYDROLOGY Stratigraphy Five major geologic formations outcrop in the Spring Valley area. The oldest formation is the Eagle Valley Evaporite. This formation consists predominantly of interbedded gypsum and dark gray shale. The quantity of groundwater which can be pumped from the Eagle Valley Evaporite varies greatly with location; however, water pumped from this formation is usually high in total dissolved solids and sulfates and is gnerally unfit for human consumption. In some cases the water from this formation is not fit even for irrigation use. Lying immediately above the Eagle Valley Evaporite is the Maroon Formation. This formation consists of red shales, siltstones, sandstones and conglomerates. Near its contact with the Eagle Valley Evaporates, the Maroon Formation contains numerous lenses of salt and gypsum beds. Groundwater availability from the Maroon Formation is site specific. Near recharge sources the water quality is generally good. In areas where gypsum and salt beds are present, groundwater is generally high in total dissolved solids and sulfates. Total thickness of this formation in the study area is unknown. Near Glenwood Springs the measured thickness of the Maroon Formation exceeds 3,000 feet. Red Mountain and Red Canyon are examples of the Maroon Formation. Next in the series of geological formations in the area are the Basalt Lava Flows. These flows form a large percentage of the surface geology in the Spring Valley area. The flows consist of a dark gray • basalt, and vary considerably in thickness over the study area. • 1 1 -5 • Jointing and fracturing are characteristic of this material. Primary porosity in the basalt is very low; however, due to the jointing and fracturing, secondary porosity may yield water in areas near recharge sources. The fourth type of material found in the area is colluvium, which consists of landslide material, mud flows and weathered bedrock. The colluvium is generally very thin and lies above the water table. This area should not be considered as a source of water. The youngest geologic material in the area is the alluvium. Alluvium is found at the lower elevations in Spring Valley. This material has been deposited primarily by streams, but may also contain older lake deposits. It consists of sands and gravels intermixed with clays and silts. The thickness in the lower part of Spring Valley varies from less than 1 foot near the edges of the valley to probably over 200 feet near the center of the valley. The Colorado Mountain College wells are drilled into this alluvium. Review of the data suggests that in some localities the valley alluvium may produce moderate to moderately high volumes of water. Geologic Structure The entire area of investigation is located on a northwest trending synclinal feature as defined by the base of the Leadville formation which exists several thousand feet below the valley. The study area lies on the northeast flank of this structure. The overall dip of the major formations, such as the Maroon, is generally to the southeast. In some localities, minor folding is present, and therefore structural trends change somewhat. • 11-6 Spring Valley lies on what is termed a graben, a down dropped block between two fault zones which trend northwest -southeast. The eastern fault zone passes through the old Hopkins homestead. The surface expression of this fault can be seen in a sharp change in slope near this point. Additional evidences of faulting are the springs which flow out of the soil along this fault. The western fault zone can be seen just west of the flat area in the low lands of Spring Valley. In both instances the faults cut through the basalt flows; however, these faults are evidently much deeper seated, and also fracture the underlying bedrock such as the Maroon formation. The faulting to the west of Spring Valley is seen in two faults which have a generally east - west trend. These • faults, indicated as terminating at the edge of the alluvial fill in • Spring Valley, may actually extend under this material. GENERALIZED GROUNDWATER POTENTIAL Figure 2, at the back of the report, defines seven areas of varying groundwater potential. Each area is discussed inchtail below. Area Al. This area consists of deep alluvial material in the lowest area of Spring Valley. Wells drilled into this material can be expected to produce moderate to moderately high yields. Water quality should be adequate for domestic supply. Exact thickness of the alluvium is not known at this time; however, at the southeast end of the valley, four wells have been drilled into this material. These wells are owned by the Colorado Mountain College and are constructed to depths varying from 220 to 300 feet. . Production of these wells ranges from approximately • • • 11-7 50 gallons per minute to 200 gallons per minute. No deep wells have been drilled in the northern part of the alluvium, but properly located and designed wells in this part of the valley can be expected to produce similar amounts of water. Water levels in the southern part of the valley are reported to be in the neighborhood of 74 to 80 feet; however, in the northern parts of the valley water levels are expected to be shallower. Area A2. This alluvial area is located adjacent to the deep alluvial deposits in the center of the valley. Geologic materials found in Area A2 consist of alluvial material, sediments of the Maroon Formation, and some basalt flows. Yields from wells drilled into this zone would be site specific depending upon thegeologic formation encountered. Water quality would be expected to be similar to that encountered in the Spring Valley alluvium. Water levels in wells in this zone should also be approximately the same as those drilled into the alluvial material. Area B. This area, located east of Spring Valley, forms the high terraces east of the Spring Valley Road. A shallow mantle of alluvial boulders and gravel lies on top of basalt lava flows in this area. One of the previously described northwest -southeast trending faults occurs in this area and gives rise to numerous springs. The exact thickness of the basalt in this area is not known; however, wells drilled to the east of the area of investigation have encountered basalt at depths ranging from 40 feet to over 110 feet below the surface. The depth and nature of faulting in this material is extremely important to well production. Therefore the area has been divided into subareas 61, 62, and 63. Area • • • 11-8 B1 has potential for individual small capacity domestic wells penetrating the basalt, which would obtain most of their water from fractures in the basalt and from gravels which may exist at the base of the basalt. Area B1 appears to have potential for small individual home wells due to the proximity of a recharge zone. It is also anticipated that the fault system which produces springs to the east may also give rise to subsurface springs which flow down -gradient into the B1 area. Area B2 lies at intermediate elevations between the valley floor and Area 61. This area is also underlain by volcanic basalt flows. Due to the distance from recharge sources, the lack of phreatophyte growth and the distance from the previously mentioned fault, a large subsurface water yield is not likely. This area does warrant additional study; however, the alignment of the fracture systems in the basalt could allow recharge to reach the area from higher elevations and from the alluvial materials in Spring Valley. Diversions from Landis Creek could also be a source of recharge. Area 63 is also covered by basaltic flows. It is located north and east of the Hopkins homestead fault zone and south of Landis Creek. The total depth of the basalt appears to be a critical factor in the water production potential of this area. The exact depth of the basalt is not known at this time, but preliminary investigations suggest that the total depth in this area is not great. Thus the Maroon Formation is probably present at shallow depths. Groundwater potential in this area is estimated to be poor. Area C. This area, as indicated on the amp, includes lands which are underlain primarily by the Maroon Formation. Because of its age and mode • • • 11-9 of deposition this formation, even where composed of sands and gravels, is very tightly cemented. The type of cement is not known; however, the formation does contain some porosity but characteristically does not transmit water easily. Water contained in the Maroon Formation will probably have high concentrations of iron and may be hard. Quantitatively, this area appears to be able to support small domestic wells. A number of wells drilled to the east of the study site have encountered yields ranging from 8 to 15 gallons per minute. These wells vary in depth, averaging about 300 feet below the surface. It should be noted that recharge to the Maroon Formation is by precipitation falling from directly above. Therefore, it is conceivable that a large number of individual wells could deplete the upper part of this formation. If future wells are to be drilled in this area, a significant thickness of saturated material should be penetrated. Care should also be taken as to quality of the water encountered. It is anticipated that some treatment, either for hardness or iron, or perhaps other constituents would be needed prior to use for domestic purposes. Area D. This area is located on the northern edge of the area of investiga- tion. It is underlain primarily by the Maroon Formation; however, just to the north of the study area, a large outcrop of the Eagle Valley Evaporite occurs. Characteristically the Maroon Formation yields very poor quality water near the contact with the Eagle Valley Evaporite. Groundwater potential in this area is therefore poor. • SECTION II WATER RIGHTS Table I presents a list of the decr ed water rights in Spring Valley. For purposes of this report the catagories as follows: have been divided into four Landis Creek Rights The Kendall-Stricklett, Landis 1, Lndis 2, O.K., Forker Gibson, Frank Chapman and Hopkins Reservoir rightks were developed almost 100 years ago to serve several separate tracts of land. Some of the original ditches no longer exist. All of the above mentioned rights and all of • the decreed water rights on Landis Creek • Hopkins Ranch. Over the years, the Hopk have been acquired by the ns Ranch consolidated all of the Landis Creek diversions to one headg3te now known as the Hopkins Ditch. This practice, though not decre d by the court, was not objected to by any other water user, sinc their practice did not injure any other vested water rights. Van Cleve and Cox Water Rights The three Van Cleve water rights, n diverted their water from year -around reservoir. The full flow of these sprin w owned by Foster Petroleum, prings located above the Quigley s has been used to irrigate crops during the irrigation season in most years. In the winter the flow from these springs contributes to the "S knowledge these spring rights have never have the potential for harming any other pring Valley Lake". To our been called out. They do not Spring Valley water right, even • • • Lc) J m DECREED WATER RIGHTS • -0 a) 7 4-, (0 "D 4-1 7 0 E a) U Q L W ct 0 V) >- w J J c^ z CC 0 Lo w f-' L a) c Name of Structure 4-+ 0 - Z •L L O O (1) V, L m a U O O O 01 61 01 O O O 01 N O1 0l 01 CO CO CO 01 01 O1 •- its 1 1 1 1 1 1 1 1 1 1 1 00 CO CO ^ ^ 00 CO CO 0 - M r 1• 1 1 1 1 1 1 1 1 I � - -1' LC1 111 Lf\ L! - O II -2 1---1--1---^0110 OLf1Lf1N MMMO M .� O OBD O '.D 10 NC, "D '.D VD M - N Olt- VD LO M 1- I- O O N. 4 - CV N N N N N Lf\ N o11-- of Ol (3l of Q1 0l of O1 00 0l O1 O1 O1 O1 01 0l O1 01 01 co co op co op co 0o co 0o O --T 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 L11 .- ^ Lf\ UN U1 Lfl O ^ CO O CO 1/40 1-- ^ N Lfl I 1 I -7 N N Lf1 M Ill co co 1s- O 0 0 •- M C) •- ^ 0 •- CY1 0 .- N I 1 1 O N N^ N N M M O 1 ' 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I I 111 ...D '.0 Ol Ol Ol Lfl - '.D U\ CO Lf\ LJ M M Lr‘ .- -1- CO a) Lf1 Ln of '.0 '.D N ti) V, 4-- 4 - In 0 co (n E E E E E (n E E E cn E E U U E w V) <n In v, w cn (n V) LL LL. 4-- 4- 4- L_ 0- a a 0. a 4- a a a 4- a o- a 14-- 14- �LI- 4- 4- 4- 4- 4- 4- 4- < < U u 0 U D) O O- D, O U D, o- o, U D, O �U1 N m u u U U U U U U in() OoND ix ^ o-. 10 10 - 01 0 Ncr, ^ O O O - •- O LI1- N Lfl N ON - 'D ffOL• O ^ M M 1_ L L L L L 1- C-) U U U U U U EEEE U 7 7 7 7 D) fl V, cc) 0) V, cn V, VI ZT •- •-•- 0) 1T o V, C •- - C C C •- •- •- C>> > C C C C •- •- "D -O -O 17 76 •- 7 7 7 ^ - - ...- - ..- ^ ^ -D L C C L- 1.- 1- C C C C L -- -- -- ^ L L ^ L L c o_J Lro n (7 V) _J -J -J -J U? ¢ Q Q 3 3' 3 3 3 1n 11) CL 3 3 3 CO 3 3 V)) cn 3 coN Beattie Enterprises V, V, a) a) L L a L L Q) (1) +-( 1J C C w w Partnership 4-) a) a) a) O) a) (1) C •- •- L L L •- .- - - 6 4-1 +J a) a) 0) +J 4-1 4-1 •+.1 •- 4-1 4-.1 4-) 4-1 4-1 4-( '- III m CO U) (1) (1) (13 CO CO CO C 0) a) O o O a) a) a) O) 7 CO m LL LL LL. m CO CO m N U U U U (r) m > CV N 7 m 01 N I CAD O 4.-+ +.1 N U) ..0 L -C a) V, a) m a) a) 1 • Vf a) U rn rn •- V, N -- •- •- •- N U L .- V, •- •- +-1 7 .- 4-I 4-) +J 4) • a) a -D -o - •- •- 4-1 a 4-1 4-4 4-1 4.) `/ a- ^^ - x E c c m .- a m ro m m - o m 7 7 7 0 0 7 7 O a) (00)0)0)0) L) 0 O O O O U CC N N m> C) m m m CO 0 4 ^ ^ Lf) •- N .- 4-) L (1) -- N O 0 3 --- C)• o 03 ^ N N > .I-1 N^ a O Z Z O C C L.- ._ - - L •- •^N +,Lzzz n a(I) m^O O O 0 m 0)C v, E (n a^) - z• u-, v, c -O O+- N a) co Z c 3 3n 0. D- ..._,..>20.) >- a .0 N O O - CO m c a) a) a) 3 .- O O •- a) Ln N CO o z z a) a) a) co .0 •- 3 3 3 a) • •- m m _Y 3 > > > > U (n L o 3 D, O •- •- a V, (n N U) V, co a) a) L C a • a) N M a C1 E E O V, o c c o C m .- .- (1) �c •- (o L) U U E N Q Q= 7 3 C •- -o -0 U U U 1 C `L • • m c) ^ ^ 10 4-I`1 _L C C C c C c ]C L (1) a.- Z$ Z C .- ^ X (n V) (n CC -- U a a L a O J J>>> O L. LL. S Q U U U C» c• a) a) a) O m o o 1 a) 1 O 0 a 0 3 3 3 U U J J m> a= x to = ut 4- U transferred to Frank Chapman Ditch Q Q m Q Q Q O '.D '.D Lfl tD •-r ^ 1- M N M M Lfl \-0 t\ Cr) M M M Ol O VD '.D 111 N OO NCO CO M M M N O1 -- -- -1- O O O O M M M M M .- L11 U1 0l'.O ^ N N 01 of Lft - --'-I-NN-3'-- '.0O M- sD^.-NN 1 1 1 1 N N N N N N M M M M 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 CO • if they are used to their full decreed capacity. • The Cox Spring has been used for many years the north end of the valley. Like the Vain Cleve III -3 to irrigate lands in springs, no one else has relied on this water in the past except for Mr. Cox. C.M.C. Wells These relatively junior water rights derive their water from the Spring Valley aquifer. They do not appear to be depleting or the aquifer. Presently, they are not affecting other vested except for the depletion to the "spill down Red Canyon". Wells and Springs The fourth catagory of water rights plus small springs and wells that have b - purposes. Most of these are decreed (Ta. We know of no interference between these when more wells are developed, we believe to many of these rights due to the indivi increased withdrawals and depletions. By law, the water rights of Spring State Engineer's Office. In recent years been called upon to administer the. waters one has claimed injury caused by another Historically, each Spring Valley Ranch h it and has not interferred with other ra reason, the Water Commissioner has not k "mining" rights in Spring Valley are the dozen en used for domestic and stock le 1) but some are not (Table 2). rights. However, in the future there could be serious injury dual and cumulative effects of alley are administered by the the Water Commissioner has not of Spring Valley because no person's water diversions. s used the water available to ches'water rights. For this pt a good record of the water diversions in Spring Valley. A review ofj the Water Commissioner's field • books reveals very little accurate informa Valley water rights. There has been discussion among III -4 ion about any of the Spring residents that has affected the flow in some springs,but action against another on this issue. Th some springs because of well pumping, but recent well pumping no party has taken serious re may be some depletion to we believe the effect has been minimal. However, the effect of many wells is cumulative and could cause measurable depletion to springs and groundwater tables. The water that has historically "spiled" out of Spring Valley down Red Canyon and reached the Roaring Fork River is considered "tributary waters". This water may have been relied upon by absolute and conditional water rights on the Colorado • or eliminated by new Spring Valley divers Colorado River could be injured. This in junior Spring appropriation If these junior Iver. If this spill is reduced ons, a senior water right on the ury could cause a call on the Valley rights, and could stop their diversions if the doctrine were strictly enfo-ced. should be called out in the future (because rights of oil shale development or the like) the keeping the junior Spring Valley rights d the purchase of exchange water out of Reu Table 2 presents a list of registere e would be several methods of verting. One method would be i Reservoir. but undecreed wells in the Spring Valley area. There are probably other wells in the basin that are not listed in this report and are unregis Ould windmillat the head of Red Canyon. ered and undecreed - such as the • • PERMIT NO. 1809 16994 18148 23991 26305 3o83oF 30831F 31599 32895 TABLE 1 UNDECREED REGISTE OWNER 0. V. Robertson Robert Hall Los Amigos Loren Kirkham Sam Campbell 1 Colo. Mtn. Coll. ? 190 gpm Colo. Mtn. Coll. ? 400 gpm William Schmid 20 gpm Paul Romisch 10 gpm 111-5 1-2 ED WELLS AMOUNT LOCATION 5 gpm SW SW 36 -6s -89W 5 gpm sw sw 6 -7s. -88w 0 gpm SE SW 4 -7S -88W 8 gpm SW SW 36 -6S -89W 0 gpm SW SW 36 -6S -88W NW sw 4 -7s -88w NW SW 4 -7s -88w NE SW 28 -6S -88W Ne SW 6 -7S -88W • • SECTION IV OPPORTUNITIES FOR COOPERATIVE USE OF THE WATER RESOURCES REASONS FOR COOPERATIVE USE Historically, no water user in Spring Valley has interferred with another user's water supply. Recently, an increased demand has been made on the water resources of Spring Valley for use within the valley and for diversion of water to users outside of the basin. This demand began with the drilling of the C.M.C. wells. Prior to that time (1967) only ten water rights were decreed for use of Spring Valley waters. Since then, over 20 water rights have been adjudicated by the water court for use of Spring Valley waters. When water rights for development purposes in Spring Valley are considered, there are some "haves" and some "have nots". For example, since the Hopkins Ranch (Beattie Enterprises) has controlled the entire flow of Landis Creek for irrigation purposes for several decades, we believe they could convert most, if not all, of the Landis Creek waters to domestic and municipal type uses. The Ranch could also "export" or sell any excess water it might have. In contrast, there are several tracts of land that are "have nots" and must develop a physical and legal water supply to develop their land. The purpose of future management of the water resources would be to equitably provide an adequate amount of high quality water to the water users in the Spring Valley area. Under strict administration of the doctrine of prior appropriation of water rights, development of Spring • • • IV -2 • Valley water resources could be restricted. For example, if the development of several large wells reduced flow in a spring, the spring "right" could shut -down the wells. With cooperation, a plan could be developed where well users could compensate for the loss of flow in a spring. Cooperation would create greater opportunities for fuller development of the water resources of the basin. Based upon chemical analysis of the C.M.C. wells, the main Spring Valley aquifer now has good quality water. As development and water uses increase in the area, the potential for pollution of the aquifer will increase. The greatest threat to the quality of the aquifer is the improper disposal of sanitary waste water, i.e. septic tank leach fields. Some of the groundwater resources in the Spring Valley area (in areas B and C as shown on Figure 2) are being recharged slowly and could be destroyed if heavy withdrawal ofgroundwaterwere made by wells. Management (planning ahead) could limit the number of wells and the amount of water pumped from those aquifers, thus preventing destruction of a non-renewable water resource. If excessive withdrawal is not prevented, wells could go dry, creating new water resource problems. One domestic well— per 40 acres would not cause excessive withdrawal in the B or C zones. WATER MANAGEMENT DISTRICTS Water diversions in the State of Colorado are administered under the prior appropriation doctrine by the State Engineer's Office; however, the appropriation doctrine can be circumvented by forming special Water Basin authorities. • IV -3 The development of domestic and municipal water supplies can be controlled by the formation of special quasi- governmental districts such as a Metropolitan District, a Sanitation District, a Water District or a combination of the above functions into one unit. These districts can develop standards for the amount and location of water use and for waste water treatment; they can impose these standards on water users within their jurisdiction. The first step in forming a Water and Sanitation District is the preparation of a service plan to guide the development of the water supply and waste water treatment facilities within the district's boundaries. Such a district is not obliged to construct any facilities when it is formed. Separate facilities within the district need not be ainterconnected. A district authority could provide management service for many independent areas: for example, coordination of well spacing, enforcement of adequate waste water treatment, billing for services rendered, provision of a better tax base for financing, promotion of joint facilities to reduce unnecessary capitol expenditures, etc. Possible diversion of water by users outside the basin and potential water rights problems caused by the reduction of "spills" down Red Canyon indicate it would be advantageous for the landowners in the Spring Valley basin to cooperate in developing a unified water policy. • • • SECTION V CONCLUSIONS AND RECOMMENDATIONS CONCLUSIONS The water resources available in Spring Valley greatly enhance the value of the land in this area. The major sources of water within the basin are the small springs scattered throughout the area, the upper portion of Landis Creek, and the Spring Valley aquifer which contains about 16,000 acre feet of water. (This 16,000 acre feet is approximately the total annual precipitation falling on the basin.) Much of the area has good potential for individual domestic wells (see Figure 2). The main aquifer is expected to support moderate to high yield wells. Each year the Spring Valley basin produces excess water which spills down Red Canyon. We believe it is possible to develop a basin -wide agement plan which would control the water level in the aquifer by pumping. Spills would then be contained to balance new consumptive use. The topographic area tributary to Spring Valley is approximately 11 square miles; however, the hydrologic tributary area is somewhat larger. Evidence of this can be seen in the Colorado Mountain College wells, which lie outside of the topographic boundary of the basin but draw their water from the Spring Valley aquifer. The areas of land which are topographically outside of Spring Valley,but which contribute hydrologically to the aquifer, are those lying northeast, east, and south of the basin. There are more than 2 dozen decreed water rights in the Spring Valley area. The senior rights (decreed prior to 1950) are all owned by Beattie Enterprises or Foster Petroleum. The remaining junior water rights are owned by many small water users and are generally for small amounts of water. man- • • • V-2 Some land owners are "haves" and others"have nots" when it comes to physical water supply and to water rights. The Spring Valley aquifer, Area A, is potentially the most valuable water resource in the basin. The saturated thickness of the aquifer is estimated to be 150 feet, based on available well logs. From pumping tests conducted at Colorado Mountain College wells, Wright Water Engineers has computed that water in storage is about 20 percent. Therefore, it appears that from 18,000 to 27,000 acre feet of water is stored in the main aquifer, depending upon the thickness of saturated alluvium in the northern part of the valley. Only a portion (5% - 20%) of thisgroundwater is available for economic withdrawal. We believe that there are sufficient renewable water resources in the Spring Valley area to safely support development that would consumptively use up to 1,500 acre feet of water annually. This water could be used to irrigate 1,000 acres of land or support up to 20,000 people if irrigation were severely restricted. It is more probable that the ultimate development of water resources of the valley will be used to support fewer than 10,000 people, some irrigation, and some export of water to users outside of the topographic basin. Recharge rates to the alluvium cannot be accurately estimated because of the wide range of recharge sources. These sources include surface infiltration, seepage from the "Spring Valley Lake", and subsurface recharge to the alluvium from bedrock sources plus surface water recharge. It is even possible that lowering of the water level in the aquifer could increase recharge from the sides and from below. This cannot be evaluated with present data. Conservative estimates of potential recharge to the alluvial material would be in the magnitude of 500 - 1500 acre feet per year. • • • V-3 Spring Valley receives water from the Basalt Formation (Area B on Figure 2), which lies outside of the topographic boundaries of the Spring Valley Basin. For example, surface water near the old Hopkins Homestead drains into Mesa Creek, but the water that infiltrates the ground near the Homestead eventually drains into Spring Valley. Published data (see bibliography) indicates that primary porosity in similar basalts is almost nonexistent: However, secondary porosity (fractures) is estimated to average about one percent. Because of the nature of the fractures, well yields can vary greatly from one locality to another. In areas where the fracture system is relatively extensive, it may be difficult to develop dependable groundwater supplies because water in the fractures drains rapidly to springs lower in the valley. Groundwater levels may show considerable fluctuation depending upon the season. An important recharge zone to Area B appears to be the area traversed by the Hopkins homestead fault zone. Numerous springs flowing from this fault zone supply direct recharge back into the basalt. Another important recharge zone within Area B is the high ridge above the fault zone. If septic fields or other sources of contamination are located within this area, springs could be polluted. Septic system location is extremely important in Area B. If sufficient deep soil dcesnot exist over the basalt, the fractures could serve as direct conduits to the groundwater. Without the filtering action of such porous media as soil, not only nitrate pollution,but also fecal contamination of adjacent wells could take place. • • Water levels in at about the 7,400 f 200 feet of saturate This assumes that so reach depths of abou formation has been e Wright Water Enginee in the Spring Valley per year. Much of t reaches the lower Spr ground flow. If thi would receive propo The exact relat springs cannot be ev be assumed, however, pumping would affect Properly constr Area C should have n the Maroon Formation such systems should V-4 the Maroon Formation (Area C in Figure 2) occur sot level in existing wells. A well penetrating thickness probably would be the economic limit. e of the wells at higher elevations would possibly 700 to 900 feet. The water in storage in this .timated to be 4 percent of the saturated thickness. s estimates that the recharge to the Maroon Formation area is one -inch per year, or about 300 acre feet is 300 acre feet of annual recharge eventually ing Valley aquifer (Area A) via springs and under- water were intercepted by wells, the main aquifer rtionally less water. ionship of the water in the Maroon Formation to area :luated using presently available data. It should that large-scale development and subsequent heavy the flow of some of the springs. ucted and located septic systems in most parts of • significant effect on groundwater quality within In localities where thereisevidence of faulting, not be permitted, • • • BIBLIOGRAPHY U.S. Geological Survey, Geology of Glenwood Springs Quadrangle and Vicinity, Northwestern Colorado, Bulletin 1142-J, 1963. Colorado Geological Survey, Roaring Fork and Crystal Valleys: An Environmental and Engineering Geology Study, Environmental Geology No. 8, 1974. State Engineer's Office, List of Registered Wells, 1975. U.S. Dept. of Health, Education, and Welfare, Manual of Septic Tank Practice, Publi ication No. 526, 1957. c Health Service Publ U.S. Dept. of Agriculture, Soil Conservation Service, Soils and Septic Tanks, Agriculture Information Bulletin 349, March, 1971. Wright -McLaughlin Engineers, Roaring Fork River Basin Water Quality Management Plan, May, 1974 Mallory, William W., The Eagle Valley Evaporite, Northwest Colorado - A Regional Synthesis, U.S. Geological Survey, Bulletin 1311-E, 1971. Wymore, Ivan F., Estimated Average Annual Water Balance for Piceance and Yellow Creek Watersheds, Colorado State University Environmental Resources Center, Technical Report Series No. 2, August, 1974. Myers, J. Stuart, Evaporation From The 17 Western State, U.S. Geological Survey Professi onal Paper 272-D, 196 2. Miller, J.F., Frederick, R.H., and Tracey, R.J., Precipitation - Frequency Atlas of the Western United States, Volume III - Colorado, U.S. Dept. of Commerce, N.O.A.A., 1973. DEFIN DEFINITIONS cfs gpm AF CONVERSIONS 1 cfs 1 cfs 1 cfs = 1 AF = 1 AF = TIONS AND CONVERSION FACTORS Cubic foot per second - a rate of flow Gallons per minute - a rate of flow Acre foot - a volume of water equal to 1 acre covered with 1 foot of water 449 gallons per minute 646,300 gallons per day 1.98 acre feet per day 43,560 cubic feet 325,900 gallons LAKE SPRINGS RANCH PLANNED UNIT DEVELOPMENT PRELIMINARY PLAT LA<E SPRINGS RANCH PLANNED UNIT DEVELOPMENT Garfield County, Colorado Preliminary Plan Submittal OWNER: Foster Petroleum Corporation [):SIGN TEAM: Civil Engineers: Eldorado Engineering Company Glenwood Springs, Colorado Planning: The Land Design Partnership Glenwood Springs, Col orado Soils/Geology: Chen and Associates Soils Engineers Glenwood Springs, Colorado Water Engineering: Wright Water Engineers Glenwood Springs, Colorado Date: June 22, 1979 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 F STI -:R PETROLEUM C adR ATION 242 MAIN STREET CAR : ONDALE9 COL` $ '' A =0 23 June 22, 1979 Board of County Commissioners Garfield County P. 0. Box 640 Glenwood Springs, Colorado RE: Preliminary Plan Submittal Lake Springs Ranch Planned Unit Development Gentlemen: Please find enclosed for your approval, the documents and maps relating to the Preliminary Plan for the Lake Springs Ranch P.U.D. The property under consideration is under the ownership of Foster Petroleum Corporation. The information has been prepared by a design team consisting of Eldorado Engineer, the Land Design Partnership, Chen and Associates and Wright Water Engineering. The submittal is in conformance with the P.U.D. zoning submittal previously approved by the Board. Should the Board require additional information or documentation to supplement the materials contained herein, we will be available to work with your planning staff to provide the same. DLS:mw Enc, Sincerely, Duncan L. Sinnock Real Estate Investment Manager TABLE OF CONTENTS GENERAL INFORMATION Fact Sheet Lake Springs Ranch P.U.D. Zoning Regulations 3 Lake Springs Ranch Subdivision Regulations 6 Covenants 7 Schools/Parks Dedication 7 PHYSICAL INFORMATION Geology and Soils Summary 8 Vegetation and Wildlife Summary 9 Road Network Summary 11 Drainage Report 12 UTILITY INFORMATION Domestic c Wa ter System 14 Wastewater System 21 Underground Utilities 24 Appendix A, Engineering Geology and Preliminary Subsoil Investigation 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 FACT SHEET LAKE SPRINGS RANCH P.U.D. Name of P,U.D.: Lake Springs Ranch Planned Unit Development Owner of Ranch: Foster Petroleum Corporation c/o Mr. Duncan Sinnock, Real Estate Development Manager P.O. Box 698 Carbondale, CO 81623 Telephone: 963-3200 Preliminary Plat Prepared By: Eldorado Engineering Company 823 Blake Avenue, P.O. Box 669 Glenwood Springs, CO 81601 Telephone: 946-8536 Adajacent Landowners: See Preliminary Plat Acreage and Dwelling Unit Summary: ACRES UNITS Residential/Single Family District 243.9 (5:1.2) 00 District density .78 units/acre Residential/Cluster/Single Family District 11.1 (2.5%) 3 District density .27 units/acre Agricultural/Open space Lower area 96.8 Park area 7.9 Upper areas 52.4 157.1 (35.6;) Proposed Road System 32.7 ( 714%) TOTAL ACREAGE *444.8 (100.7%) TOTAL DWELLING UNITS 193 -1- 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 *Note that the acreage from the legal description is 441.8 acres. The acreage discrepency will be resolved when lot sizes are calculated at sinal plat. Gross project density - 0,44 units/acre, Zoning: The subdivision is zoned under a Planned Unit Development as approved by the County Commissioners on May 14, 1979. The pre- 1ihuinary plat is in conformance with the PUD zoning approval. Please see the next section for the PUD zoning regulations and proposed covenants. LAKE SPRINGS RANCH P.U.D. ZONING REGULATIONS Section I. PURPOSE A. To carryout the purposes and provisions of the Garfield County Zoning Resolution, Gar- field County, Colorado and in particular Section 14.00 of the Garfield County Zoning Resolution, as amended, the Lake Springs Ranch P.U.D. Zoning District is further divided into the following zoning district classifications: R/S.F. - Residential/Single Family District R/C.H. - Residential/Cluster Housing District A/O.S. - Agricultural/Open Space District Section II. R/S.F. - RESIDENTIAL/SINGLE FAMILY DISTRICT A. Uses, by right. .Single -Family dwelling and customary accessory uses including buildings for shelter or en- closure of small animals or property accessory to use of the lot for single family residential purposes and fences, hedges, gardens, walls and similar landscape features. Park and Greenbelt. B. Uses, conditional. None Uses, special. None D. Minimum lot area. 1 acre E. Maximum Lot Coverage. 15 percent -3- F. Minimum Setback Front yard -- 30 feet Side yard -- 20 feet Rear yard -- 50 feet G. Maximum Building Height 25 feet Off -Street Parking/Residential Four (4) off-street parking spaces on the same lot for each dwelling unit or one (1) space per 600 square feet of floor area whichever is greater. Section III. R/C.H. - Residential/Cluster Housing District A. Uses, by right Single -Family dwelling, Duplex dwelling, Triplex dwelling and customary accessory uses including buildings for shelter or enclosure of small animals or property accessory to use of the lot for residential purposes and fences, hedges, gardens, walls, and similar landscape features. No more than three dwelling units may exist in the R/C.H. District. Park and Greenbelt. B. Uses, conditional. None C. Uses, special. None D. Minimum Cluster Housing lot area. 1. The Cluster Housing Lot shall be as shown on the P.U.D. Plan. 2. Lots within a Cluster Housing Lot shall have no minimum lot area. -4- E. Maximum Coverage of the Clus eer Housing District 1. 5 percent of the total District area. 2. Lots within the R/C.H. District shall have no coverage limit except that the combined coverage of all internal lots shall not exceed the 5 percent maximum of the total District area. F. Minimum Setback from the ClLster Housing District Boundary 1. 50 feet 2. Lots within the R/C.H. District shall have no setback requirements. G. Maximum Building Height 25 feet H. Off -Street Parking Four (4) off-street parking spaces for each dwelling unit or one (1) space per 600 square feet of floor area, whichever is greater. SECTION IV. A/O.S. - AGRICULTURAL/SPEN SPACE DISTRICT A. Uses, by right. Recreational including, stables, riding arena, kennal, pasture, water impoundments and customary accessory uses including buildings for shelter or enclosure of animals or property employed in any of the above uses. Recreation Vehicle Storage Park and Greenbelt B. Uses, Conditional. None C. Uses, Special None D. Minimum Lot Area 2 acres LAKE SPRINGS RANCH SUBDIVISION REG Except for the following section o Subdivision Regulations, all provi County Subdivision Regulations sha the Lake Springs Ranch P.U.D. The Subdivision Regulation which shall is as follows: Section 5.09 -6- -LATIONS the Garfield County :ions of the Garfield 1 be applicable to Section of the said have no applicability COVENANTS To further assure the development Lake Springs Ranch as a high quali protective covenants will be recor plattings of the P.U.D. Following cular importance to be included in preliminary draft of these covenan to the County Planning Department. 1. Architectural Committee --Building siting --Site and structural design --Landscaping --Fencing restrictions 2. Lot Use Restrictions --Residential structure --Garage/storage structure 3. Animals --No horses or livestock on 1 --Dog kenneling requirements 4. Underground Utilities Required 5. Vehicle Control --Limitations on recreational 6. General Site Maintenance 7. Noxious Activities 8. Easements 9. Signs 10. Temporary Structures SCHOOLS/PARKS DEDICATION In accordance with Section 5.11 of gulations of Garfield County, Colo the Lake Springs Ranch P.U.D. owne the Board of County Commissioners pensate the county for the reasona facilities (schools/parks) require of the P.U.D. -7- nd continuation of y residential area, ed along with the final are topics of parti- the covenants. A s will be provided ehicle storage the Subdivision Re - ado, as amended, s will cooperate with o appropriately com- ly necessary public by the future residents GEOLOGY AND SOILS SUMMARY Appendix A contains the Engineering Geology and Preliminary Sub- soil investigation conducted on the site by Chen and Associates dated January 30, 1973. The report was performed for a recent Preliminary Plat submittal for the same property but with a dif- ferent development pattern. The report therefore references various blocks and roads which have now been relocated, as evidenced by the site map (Figure 1) in the report, but the basic analysis and conclusions are obviously still valid. Also included at the end of that report for reference are the previous responses of the Colorado Geological Survey. VEGETATION AND WILDLIFE SUMMARY The sloping terrain that is proposed for development, which for this discussion will be called the upper slopes, is covered by sage and discontinuous native pasture grass growth with occasional open stands of gambels oak. The lower portions of the site consist of intermittent and permanent ponds and continuous growth of native pasture grasses. These areas have high groundwater tables and are not suitable for development. As a result, these areas have been set aside for open space and common area. The transition zone between the areas, primarily along The Corduroy and County Road 114 and the Van Cleave Road area, has vegetative types common to both the upper slopes and lower areas. This such that a buffer area has been selectively chosen for development zone exists be tviy en the developed areas and environmentally sensitive lower areas. he ' Q upper lower areas and scattered Agricultural/Open Space areas on + slopes, as well as the restricted lot development, the natural vegetative conditions and hence the natural appearance of the area will be retained. r the With the retention of Conversations wi th the Division of Wildlife Officers indicated that this area is generally considered to be an intermediate fail and winter range for deer and forms part of the migratory corridor between seasonal ranges. • In that light it was recommended that fencing be restricted to buildings and irrigated land, that dogs be required to be kenneled and not be allowed to roam, both of which have been in- 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 clouded in the Zoning Regulations. With these restrictions, the im- pct on the deer population wi11 be minimized. Prohibition of horses on individual lots was recommended to avoid destruction of the natural vegetation necessary for the small mammal and bird population. Grouse populations have been ir.dentified near the Lake Springs Ranch site but not on the site. These birds were identified as being possibly impacted, if they do exist on the site, by the development. 1 e 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ROAD NETWORK SLi,'- I-tARY The proposed road network is shown on the Pian and Profile Sheets and the Site Plan . The road system his been designed to conform both horizontally and vertically to the existing topography to the greatest extent possible to minimize cut and fill requirements, minimize roadway scars and still remain within the County design standards. Typical cross-sections are also depicted graphically in the Plans. In addition to the proposed typical sections are two sections taken at critical cut and fill locations. The section from Quigley Road indicates the most severe construction situation in the development in terms of natural ground surface and maximum fill. More typical is a cut or fill situation of a maximum 2' to 3' or less across the front of individual dots. Also shown is a cross-section from Valley View Road showing the situation at a culvert crossing. It is proposed to retain the horizontal and vertical alignment of County Road 114. County Road 119 will retain its original align- ment until it departs from. the northerly boundary of the develop- ment at which point its present location will be vacated. County Road 119 will require some selected upgrading in terms of widening and regraveling to bring it up to the condition of the other proposed roads. -11- DRAINAGE REPORT The on-site drainage patterns will not be altered by the P.U.D. The single family lots proposed are one acre or greater and with a total potential lot development of 1O% to 15% maximum and in the majority of lots on the order of 5 There is ample land area on each lot to prevent encroachment on existing drainage ways. The overland drainage will continue to flow as it presently does, with some minor channeling due to intersecting roadways. The drainage system will be augmented by culvert pipes at road crossings. All culverts were designed to handle a 1 -hour, 25 -year storm occurance using the Rational Formula. The Drainage Plan indicates the location and size of proposed culverts as well as the projected maximum flows at each point. Culverts will all have minimum slopes o 1% and in most cases will follow the natural slope of the land which is for the most part 5% or greater- Because of the low density and convenants protecting natural vegetation, there will be minimal increases in the quantity of run-off. The minimum culvert size will be 18". Culverts will be constructed with end sections or headwalls to maximize carrying capacity. Drainage basins considered are shown on the Drainage Plan as well as the larger vicinity map attached hereto. -1 2- 1 2 0 ,'• • /745is IrL' I; • —777; f 6j 1 j' •!i '11 YJs�►�fni�\ighlGl '-`t t1-, ,'\ I -'9 \ ,.... .. 1�� ;,, I 23 , !I AI 91, II \ t 1 i • \ \\\ k, oiropkins c{,me tead� _.: 1 �' 3 • r4, /4; N._ 1 fir;?%1 !i`•� 0/ / �ff \\- -- - \!\ 1. 1. C•\ {4 \\,71•42 \ r 1� /V • i� L V / -/ l Cern • DOMESTIC WATER SYSTEM The proposed domestic water system is shown on the Utility Site Plan. All construction will be in accordance with, and all Plans and Specifications will be reviewed by, the State Health Department. It is the intent of the Developer to construct and finance the construc- tion of the water system facilities and to transfer ownership to the Lake Springs Ranch Homeowner's Association, The Association will be responsible for the operation and maintenance of the system as well as collection of user charges to finance the same. The Association will be organized as a Colorado non-profit corporation with an elected Board. The system has been modified slightly from the sketch plan in terms of the physical layout on the ground, The design parameters have not changed in terms of sizing, demands, etc., however, to take advantage of the topography and to reduce the pumping costs, three (3) pressure zones were created such that only the water actually used in the zone will be transferred to that zone, The storage facilities for the upper zone and lower zones (both lower zones are served by the same storage tank) are sized in proportion to the number of units in each zone while main- taining fire protection within each area. The lowest pressure zone is reached through pressure reducing stations from the intermediate zone. The zones were established generally to provide a 90 psi to 30 psi static -14 pressure range within each zone within the topographic limits of each zone. The alternative to the pressure zone arrangement above is a one storage facility for the entire system and defining the same zones with pressure reducing valves. This has the advantage of reducing the number of pumping facilities and storage tanks but requires more water line and increases pumping costs. This alternative will be fully evaluated on a cost/effective basis during preparation.of final construction documents. Following is correspondence from Wright Water Engineers concerning the water rights for the PUD. The December 20, 1978, letter indicates the three VanCleave rights owned by the Developer. The analysis performed to determine the consumptive use in this letter is no longer valid since the septic tank trea tient referred to is no longer being used in lieu of c ; ntra 1 treatment. The rani sad wastewater trey Cment schema has been reviewed by Wright Water Engineers in a letter dated April 2, 1979, and it was found that the water rights available are sufficient. The Court Case number for the Lake Springs Ranch water system is as follows: Augmentation Plan: W 3571 Wells: A 3572, W 3573, W 3575 The original filing was made in December, 1978, and as a result of the change in wastewater treatment, refiled in February, 1979. The augmentation plan involves transferring the three VanCleave rights to -15- the wells and changing the designated use from irrigation to municipal and domestic. -1G- 0 ••" [ tv Of 1 1E( P ELU), PO; }PI 'a COLC)HAL, C, P'LI 1 GL LrIry C•O:"• RINGS +ICE PC' NO,, 12E6 C.LF'IV. C•4C cruiracs COLC+UA:)Ck Pile, STL ..BOAT OPE ICE PO BOX EZEO LFMN.JAE +/ILLAGE. COLORADO EQ.99 S4N1 D GOM.INC.0 OFFICE HIGHC-./.ENA WATER rNC.INCE HS ICM LY, A.ITIGUA CARH£TERA 0,IARTE SANTO D:)M1NCO. DOMINICAN REPUBLIC WRIGHT WATER ENGINEERS, INC. Duncan Sinnock Foster Petroleum Box 698 Carbondale, CO 81623 Dear Mr. Sinnock: ENGINEERING CONSULTANTS 2-z0 ALCOTT 4 THPET DENS,' H. COLORAOO 60211 3031 n66•6201 Glenwood Springs Tel. 945-7755 December 2.0, 1978 RE: Revised Water Supply Plan for Lake Springs Ranch .•11 I, Ri: RP'!C' t• ;.FIf 1..11•.11 TORrr. Based upon Mr. Ron Liston's revised land use plan for Lake Springs Ranch, we have revised our water requirement estimate for the development. With the aid of Mr. Scott Balcomb, water attorney for the development, we have developed the following water resources strategy to meet the ultimate physical and "legal" needs of the project. WATER NEEDS The proposed development will have a maximum of 195 single family units. It has been assumed that each unit will have an average of 3.5 people requiring 100 gallons per day per person for inhouse use. In addition, the development's water supply system will provide enough water to irrigate 2,000 square feet for each lot plus 20 acres of additional open space irrigation. Total irrigated acres will be 29. Lawn irrigation requirements for the development were calculated (Jensen-Haise method) to be 1.5 acre feet per acre of consumptive use. Assuming a 60% irrigation efficiency for the development, the irrigation requirement will be 2.5 acre feet per acre. Waste water treatment will be by individual septic tanks. Effluent from the septic tanks will be received by leach field or ET (evapotranspiration) disposal systems. The consumptive use of the inhouse water through the individual waste water treatment systems will range from 10% to 100%. For this plan we have assumed that the average consumptive use of the waste water treatment system will be 25%. Annual water requirements for full development are as follows: TOTAL REQUIREMENT CONSUMPTIVE USE Domestic (195 units) 77 acre feet Irrigation (29 acres) 73 acre feet -17- 19 acre feet— �l,t 44 acre feet 150 acre feet 63 acre feet Mr. Duncan Sinnock -2- December 20, 1978 WATER SUPPLY AND WATER RIGHTS It is our opinion that the proposed development has access to a reliable long term water supply. Besides having a continuously flowing spring of about 0.5 cfs, part of the development is located over a large ground water reservoir which we believe contains more than 10,000 acre feet of water that is constantly being recharged. Lake Springs Ranch owns the following water rights: NAME OF .DITCH AMOUNT APPROPRIATION DATE ADJUDICATION DATE Van Cleve No. 1 1.4 cfs 9-05-1882 5-11-1889 Van Cleve No. 2 .9 9-15-1882 5-11-1889 Van Cleve No. 2 2.0 5-15-1884 4-18-1890 These rights have irrigated about 70 acres of land and have had a historic consumptive use much greater than what is anticipated for the proposed development. These rights derive their supply from the Quigley Spring which we estimate to yield from a low of 300 acre feet per year to more than 1000 acre feet per year. According to James Quigley, there have been 35 acres irrigated under the Van Cleve No. 1 and an additional 35 acres under the Van Cleve No. 2. The State Engineer's office reported a minimum irrigated acreage under both ditches of 120 acres. Reviewing aerial photography of the area, Wright Water Engineers concluded a maximum irrigable acreage under both ditches equals a total of 120 acres. According to Mr. Quigley, all of the water available from the spring was diverted during the irrigation season to one or the other of the Van Cleve Ditches. Minimum diversion for a 160 day irrigation season would be 160 acre feet. Assuming 40% of this diversion was consumptively used, then the historic consumptive use would be 64 acre feet. This minimum of 64 acre feet of historic consumptive use is more than the proposed consumptive use. We recommend that Lake Springs Ranch apply for three 200 gpm well permits and have these wells adjudicated as soon as possible. An augmentation plan should be submitted to the water court which would transfer the historic consumptive use from all of the Van Cleve water rights to an alternate point of diversion at the wells and the spring. We believe that the available physical and "legal" water supply can be developed to adequately meet the domestic needs of the proposed Lake Springs Ranch development, even in the dryest years. -18- Mr. Duncan Sinnock December 20, 1578 -3- If you have any questions on the above, please don't hesitate to contact us. WLL:ep cc: Scott Balcomb Dean Gordon 741-22 Very truly yours, WRIGHT WATER ENGINEERS, INC. ''�By .1.%j'L:-•,r,,,1 IJ1 William L. Lorah -19- A.PFN O - CE P 0. BOX 8028 ASPba, COLORADO 81611 CHEYENNE OFFICE 3228 LOCUST DRIVE CHEYENNE. WYOMING 82001 GLENWOL,D SPRINGS OFFICE P.O. PDX 1286 GLENwOOD SPRINGS, COLORADO 81601 STEAMBOAT OFFICE P.O. BOX 5220 5TEA1+.r.OAT 'VLLLAGE, COLORADO 80449 VVRIGHT WATER ENGINEERS, INC. ENGINEERING CONSULTANTS 2420 ALCOTT STREET DENVER, COLORADO 60211 (303) 453-6201 Duncan Sinnock Foster Petroleum Box 698 Carbondale, CO 81623 Dear Mr. Sinnock: Glenwood Springs Tel. 945-7755 April 2, 1979 KENNETH R WR1GHT WIll1AM i LORAN RUSSELL F DAR. RICHARD D. JOHNSON J. CRAIG GREEN H. RAY NtwMYFR MARILYN M. STOKES RALPH t TOREN FRANK 1 TRELEA5E RE: Lake Springs Ranch Water Rights According to Ron Liston the revised Lake Springs development will provide central sewer collection and treatment facilities for the equivalent of 195 single family residences. Current plans envision the expansion of the existing CMC waste water treatment facility to serve CMC, Lake Springs Ranch and Los Amigos. Wright -McLaughlin Engineers is in the process of developing a service plan for the area's waste water treatment needs. Previous water supply plans for Lake Springs Ranch (see our letter of December 20, 1978) assumed the development would be served with individual septic tank/leach field systems. That plan assumed that about 25% of the inhouse domestic water would be consumptively used. The revised plan to use the CMC plant would mean that the inhouse domestic water requirement of 77 acre feet per year would be a total depletion from the Spring Valley area since the return flow from the sewage treatment plant would not be to Spring valley. It is our opinion that the water rights applications currently before the water court, when approved, will provide sufficient water to meet water requirements for the subdivision without injuring other vested water rights in the Spring Valley area. WLL:ep 741-22 Very truly yours, WRIGHT WATER ENGINEERS, INC. William L. Lorah -20- WASTEWATER SYSTEM Lake Springs Ranch will be incorporated into the Spring Valley Sani- tation District which iS now in the process of being formed. The purpose of the District is to provide wastewater treatment for Colo- rado Mountain College (CMC), Los Amigos PUD and Lake Springs Ranch PUD. The proposed treatment site, as shown on the following vaci ni ty map, will be at the existing CMC treatment site. The existing CMC treatment facilities will be upgraded and expanded to meet all applicable dis- charge requirements and will be sized to meet all future requirements of the areas referenced above To d..Ce, an agreement has been reached between CMC and Los Amigos PiJO to incorporate the existing treatment site into the Sanitation District and agreement in principal for the formation of the District. Lake Springs Ranch PUD has not been a party to that f the fact that their position in the subdivision process agreement b u because :.l! e � :� did nolt allow them to participate without rest rict.ijje conditions. ions. As shown in the SpringValley Sanitation District Service Plan, prepared for the formation oF the District and on file in the County Planner's office, the facilities are being designed in anticipation of the inclusion of tho Lake Springs Ranch PUD into the District. The Service Plar is based on a total buildout of 195 single family units at 3.5 capita/unit and 100 gallons per capita per day. The wastewater collection systems on site is as proposed on the Water and Sewer Utility Pian and the Sewer Plan and Profile sheets. All collection lines will be 8n diameter laid at a minimum slope of 0.4% or greater. The col- lection system will require a lift station to service the VanCleave Road area. Additionally, Lots 1, 2, 11, and 12, and possibly Lot 13, Block 2 cannot be serviced by gravity sewer. It is proposed to service these lots by (1) installing an in-house grinder type pump to pump directly to the force main or (2) installing a conventional home submersible sewage sump pump, following a septic tank for solids removal, and pumping to the force main. The individual lot owner would have the option of the col- lection facility to be used. Off-site sewer from the PUD boundary to the treatment facility will be gravity sewer. The sewer will run approximately parallel to County Road 114 and will actually connect to the treatment facility through either the CMC or Los Amigos collection systems. These two alternatives are being analyzed on an engineering feasibility and cost-effective basis with the two entities now that the Sanitaiton District is, in fact, being forried. In either case, no lift station will be required in the off-site sewer system. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 U; 1' E DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY 303 29 .NWOOD R I N t7 . _--• .„ • ) tt--T 110 - • r• 12 27 .1,', —I • . •---- 1 • _11 / .1.• fr• /ft!, /.• T. 6 5. T. 7 S. 4372 7212 3 • , • — - • ' \ 1- 732 6923 :- '"'. •. --',":___.=_- - ' --... .: -- 2- 2 — —71„...,, •" __•- • i - .. • 4. 7, c... 1. ----__ s ., ....--- -1 ' . -:' .• \ ..-' .......- r '... .-- \ • --' --". ; ', r- 'i' r 'N -, ‘...- -----.-- '1----- . 63.21f :.--;•._ /- - ‘‘, I 'A.:, :,` 4 , - - — ,I. r ' '.., ..."(..-.. ' '44! '3‘ ... \ . --:,'-' "-- - ' ' • N • / , ' N\ ' . 4 -- . „,,„..0 , ----..-"-":;44 "'r51 4,'..' \•, • , \ ',. - t. St:, .4,,,,,t. 00.1.44!...A. , ''. \ '',.':-.. \ I. '--- -•,/''.'_ . - . __ • • • 4371 ..::— __. `'•".,41 -_.___.-------1,7--- 7--___________--- , . .1 :.---77_-.-__:-.2%:5,-"r-.-.__----_.L'..- • ' _ 7,,._-.----- i, , - II *V• , I ' ` -_,-4-= • , ' '5e,;.‘.....\\ ••• '... \ 's. • ' /---- • • -,--- . '' -- :' v . — • i . v f----• 0, • _ - , - ...7 - - -------: , e , ../. rt-- 4 ----.:--,:..,, • .4'"..1';t-.-7-17.;-'747",..;• '. - 1 1 - ',`-P' '--. 1' ' 1C-- . ' 1 . •- .. •..._ 1 •••••, . .• ./ :-.....3 7/ '''f•k/2 \Z{X-- - - ! ' ‘ • - i . ' ' ' '. . ' '-- I ' - - " - - • ' • • ' ' , ''' ) ''' I I • • - ..1 • .','•;-,:- ‘:..\\\\•• - • .; - / "•- ..-1 j ,Z"--, . ') ' , • ] ,, ._ _. r---7‘ '.-------------2..1.1; ir• \ ; / ) ' <•-'-----------__2------7; (\ '----___ C.). -9 1-- - --••__-- - - -- ; -_:__- .- ,---, ,, • .----- .2„--_------------------ --* '..--__ -______.- • „--- ,- — s--.. , 437-D 2730' • /- ' ( • Y I • -" - C ' _ „\, , " • • '72. - , _ _ - •.: - — - - _ _ -C„ 7 v. _ - - • • 64 t c _ -- - 1 t- •.: --1-7-- I 00_7 6f,e. zoc0 . _ UNDERGROUND UTILITIES The three concerned utility companies -- Rocky Mountain Natural Gas, Holy Cross Electric Association, and Mountain Bell were sent Prelimin- ary That site pans on June 11, 1979, in order to afford all parties the opportunity to discuss the project at the Utility Coordinating Com- mittee meeting on June 21, 1979. As of that meeting only Mountain has had an opportunity to formalize any construction requirements. They have indicated that they will require a 5' right-of-way on all lot lines fronting public roadways. Rocky Mountain Natural Gas has indicated informally that they can pro- vide services by extending distribution lines from the approximate Vicinity of CNC. They have not indicated their easement requirements within the PUD. Holy Cross Electric has as yet not formulated any require- ments. It is an.icipa`ed that both utility c+Jrnpaniss will indic<te easement requirements during the formal Preliminary Plat review period. iron of the utilities expressed any foreseeable difficulties in servicing the PUD during discussion at the Utility Coordinating Committee. -24- APPENDIX A ENGINEERING GEOLOGY AND PRELIMINARY SUBSOIL INVESTIGATION :51 ''''.4 .r1. ',-,, 1 ' .-'1 41 A ''.,-.TS'3,,.'c) .c. .1 r '. i -1s ., .! „ , :..,. , N., :, , C. ..e, a .. '',....A Cr., 0 i 1 S U L 1- I N G r. N -,,,..:4 ,-.., 1 ;.:[,) .:s1111:,7)AO ,'ATION 96 3. ZUNI • COLOR.409 $.;iY,Z23 ,:03/744-75 E E 1924 ZAST PRST WYON(ir..12601 • 397/24-2126 ENGINEERING GEOLNY AND PRELIMINARY SUBSOIL INVESTIGATICN FOR PROPOSE° LAKE SPRINGS RANCH SUBDIVISION SECTIONS 32, 33 AND 34, TOWNSHW 6 SOUTH AND SECTIOM 1, TOWNSHIP 7 SOUTH, RANGE 88 WEST GARFIELD COUNTY, COLORADO Prepared for: SCARROW & WALKER, INC. P. O. BOX 460 0.0D SPRINGS, COLORADO 81601 January 30, 1978 TALE OF CGNTLNTS CONCLUSIONS I SCOPE 2 PROPOSED DEVELOPHENT 2 SITE CONDITIONS 3 GEOLOGICAL CONDITIONS 3 Bedrock Condit!ons Sol CondItions ti Structural Geology 4 SUBSOIL CONDITIONS 5 GEoLoatc HAZARDS 6 MUERAL RESOURCES • 7 FOUNDATION TYPES 7 1 SITE GsiADING ADDITIONAL INVESTIGATION 2 FIG. i - LOCATION GE TEST HOLES. AND PITS AND SURFICIAL GEOLOGY MAP FIG. 2 - LOGS OF TEST PITS FIGS. 3 through 6 - SWELL -CONSOLIDATION TEST RESULTS FIG. 7 - GRADATION TEST RESULTS TABLE 1 - SUMI4,ARY QF LA2ORATORY TEST RESULTS (i) (2) (3) CtsNC rJa 1 „5 The proposad subdivision d v lopment l5 rL iibie from an E:3'!t)lriee; - ing ;sology and subsoil point oF view. Th rc ar a no „eoiogic hazards nor commercial mineral deposits which would randar the project unsafe, infeasible or undesirable. F-Jurtdat i ora types in Block l should consist at ped and grade beam construction a.a recommended in our original report (Job No. 14,2.35 c1ted Apa it 6, 1977). Spread Footing Foundalons occasionally utilizing d ;ad toad pressurc5 arr r a r ?1 ly sulta31 :' for idenc.es duplex i" ;ia '3 S Y; i building ovr tha ratr",dc r of (4) Additional investigation by subsoil exploration or foundation excavation inspections should be performed in Blocks 3, 4 and 5 to bettor define ,sub sci t �r� bedrock conditions and det rine ;rap>r foundation 1tln parameters at specific building sites. SCOP7 This report presents the re.,4ults of an engineering geology and preliminary subsoil Investigation for the 2T l_ak:! Springs Ranch Subdivon situated io Sections 32, 33 and 34, T. 6S. and Section 4, T. T7., R. 83W., Garfield County, Colorado. The report also presents the most probable type building foundations, recommended soli pressure ranges, engineering geologic aspects of the site, general subsoil con- ditions, and other preliminary design information suitable for general plann:ng. The inv,Istigation included a field geologic survey and exploition pits. We previously conducted a soli and foundation investigation for Blocks i and 2 of the subject subdivision end reported our results under Job No. 14,285. dated April 6, 1)77. The results of that invostiqation and a rctview of pertinent gooiogioel 1 were also a part of this investigation. Results of additionrcolation tdsts wera reported under our Job No. 15,346 cia3,1 October 13, 1f;77. PROPOSED DEVELOPMENT under3tand that the proosed Lake Springs Ranch Sudivision will have approximately 55 lot3 desir,mated for 31;>y1Fami!y residences and 7 lots with pltmneU duplex unitsit is propos:A to supply water from a community water system utilizing wells as the water source, individual sewage disposal systoms ara planned for the single-family residentlal lots. SITE CONDITIONS The Lake Sprig5 Ranch Subjivisiin as presen,11 loclndes an ar?a of apprcv.irnt,!ly 441.7 apris. The topporbdhy 'it the site is compri7.od mainly of hilly ridge and volley reliefh severl scatte;ed knobs or topographically high points occurr1n on the western portion of the site. The grDund surface at the 3ite ranges from Elevation 6890 to 7310 feet a5ovi. mean sea level. Spring 'valley occupies approximately one-quarter of the proposed subdivision on its western end. It forms the low area of elevation within the site. The strean which flows in Spring Valley oriOnates immediately upstream of a sd1 pond in the south-central portion of the site and flows generally northwesterly. The rem -lining drainarjes are intermittent and show no indication of recent erosion signifying that they cm.ry very littie surface water only during periods of ;ivy loci rdn. Th relptiv,Av ,;.nall proposed building area co ch:: west of Sprin V,::y is of ,,;ntly to ro:_ier.?tely sloping (2% to li) ,round fallinr! to4ard the dralnIg. The much larger portion of the site to the east and suutheast of Spring Valley slopes upward from the valley at gentle (I;) to vry tp (30%) slopes which sive in all directiom; but which c -h -:.ally drnh to‘4nrd Spring Valley. At the time of our geologic surv-y and lute: -t ;L•ibsoli investigation, the ground surface was covered with 1 to 2 feet of snow. The vegetation which could be obrvad was scrub oak and 51gebrush. GEOLOGICAL CONDITIONS Spring Valley Is an upland plateau valley that has been incised Into Pleistocene age basalt lava flows which cover a large upland area in this rnjion. Th a of the proposed Lake Si -,rings Ranch Subdivision extends from Spring Valley on its wern end into the hilly terrain to the 435t of the valley. B-drock Conditions: The only 1.)drock exposed on the site consists of scattered outcrops of the Pleistocene age basalt flows. These outcrops are confined to relatively small areas near the tops the scattered knob featurs and along one ridge and one road cut which is immediately outside of the sudiviion boundary. The Pennsylvanian to Permian age Maroon formation directly underlies basalt flows and a portion of the OuntQrnary solls The basalt at the site generally consists of Wihly fractured blocks of extreely arr, competnt rck. The joints are filled lqith clay. Oc.casionally large arouncs of voinanic ask vqhich Is composed of silt are present v;inin the bedro:k. Soil C•litions: The Qunt..-.:Tnry soils .,-Irent coDsist cr,1111y of resial and uolluv1.11 (sl,pp wash) clay silty cravel with cobbles and boulders on the 1.1:6pr hilly terrain and clay on the f7pntlr slopes along Spring Valley. allrvial son deposits may be associated with th.e loer ground elevations along. Sprig Vrtliey. No subsoil investigation vi, -;)s prformad alon,D the Spring Valley flood plain, and the composition of soils in that area are not known by Us. Fig. 1 presents a 5urfici,31 ‘71eologic rmv .for the propo.,..ed Lake Springs Ranch Subdivkion. Structrn1 1712.2.12.22L: Since no outcrops of the Marscn formation observed at the site, the bedding attitude is not known. However, about 5 2 miles .,..,L o1= tris :;it:y, the Moroon fo7ratien is fis ping g-nerally to the northeast. This dip probably contiriuc.; in 3 r.%;rtheast direction at the site but may be c;`'.r!ti:er than that ,.(J the west. A Pleistocene fault is present in the basalt flow '.west of Spring Valley. This fault should not htr:e ay afie,st on the proposed development. SUBSOIL CONDITIONS Fr(,m the exploratory holes dri i ;:gid for the subsci 1 investigation of Lots 1 and 2 and the test pits excavated over the remainder of the site, it was found that the subsoil conditions range from fairly uniform to.er'ratic across the site. Generally, the soils consist of tie drum stili to very stiff, sandy clay with some scatty r>d lens`, of clayey gravel t the lower elevations of the Gite and silty ciravcl, clay, t' site ,�:r�ral l ;1 val ly clay and cNr- silt In the elevations of :h` `.i' u. .. .. upper :ir n 119 as of County Road 114. The logs of r!i)rt1�4?`.,. of County '.i.;3.:3 and -,t test pits are shown on Fig. 2.. f T 1 torefeet in depth The clay and sandy cloy range iO>' ';1 than i'' n 20 the silty gravelbeneathbeneaththw� sui-1�3�.'r. Some cloy also exists .� below strata. As stated ill our original report and as shown by the results of swell -consolidation tests presented on F'ig's. 3 throU0 6, the clay is very errntic, some which possess a moderate swell potential and some porous zones whlch will consolidate moderately when wetted and loaded.. The silty gravel is present at about 1 to 5 feet deep and varies from on the order of ! to 8 Feet thick. The gravel soils contain cobbles and boulders which are generally angular to subangular; volcanic ash which ts pr..Isdominanty a silt r,terial; Ind some clay. Some of the grivl soils v4i11 cohsolicirate moderately when we..t:.:d and loaded but in general will not con_iolid.2ite a5 much as the msre corpus clay Bedrock was encountered in P1t3 2 and 3 at 2 to 5 feet dap and consistod of very fractured basalt. percolation t25t3 rep!rf,rmed as a part of this preliminary Investigation on the remaind,.,r of the site excluttva of Blocks 1 and 2. The clay soils ovr the remainder of the sit will have fairly similar percolation properties as those in Blocks 1 and 2 :/;111 the lower silty gravels will possess faster percolation rates. No free water was encountered in the test holes at th time of drilliny nor in tho bee:hoe pits ht. to time of excavation. Samples of the soils ,..%re 0o;ly-H fer se! ib1 sul,:atos. The oi 1 s have neliyib-le tH1 0.1:0 suif., cement types sho'Jld lenerally no ho re(;uirei in the coricr,::te to resist ieterioration. GEOL3Cii0 HAZARDS No conditions were observed a;1 the site which would constitute a geologic hazard. ',4e understand that the common area along the Spring Valley stream and the pond at the. upp.er end of the stream are not desinated for construction sites. These areas will probably b the onlyreas that will require construotion restraints. No ethor problems associated with the slto geology are anticipated provided that the recomendations for foundations and site gradlng di5cussed in this report are followed.. - it is our opinion there. are no. co!7,mercia1 mineral deposits as defined in the Colora=do Open nining Land Reclamation Act at the site which would be of significant economic or strategic! value. FOUNDATION TYPES The foundation types for residences constructed in Blocks i and 2 are covered under the Foundation Recommend3tions section of our original report (Job No. 14,235 dated April 6, 1977) and consIsz generally of pad and grade beam foundations for Block 1 and spreed footings for foundation types in Block 2. In general, the foundation typi:s 1n Blocks 3, 4 and 5 :houlj consist of r.o.2erately loaded spread footings. Maximum allowable soil pressures for the upper sandy clay soils will ipc. on the order of 1J:100 co 3,000 psf while mmum soil pressures for the silty sray.:1 will ronge from 2,003 to 4,060 psf. foundions on thn dc,n.-ser, stiffer clays may riluire rril n in Oaad 1 od ro;sur3 also. SL,rcc:d Footing found3tion3 on th,?, bedrock generally ma), be designed for higher bearing pressures, 1-3caus.3 of tha very- erratic cntwe of the su53oiis ;:ich respect to their occurrence and physic -0 proper:les, indiviiu61 ui1ding site should nav,. specific subsoil investigations or the foundation excavntion should be iospectd in order to det,ermine the proper foundation design requirements for the specific structures. Si. _ GRADING kfiller_3 roads and buildingis.t..s ar. c:_nst;uc.t..._• within the site,. it should be feasible l e LCA construct permanent CUE and fill Slopes up to 2:1 ho; i-zontal to vertical. 20 feetfeethigh at inct irlaf:a,;; not exceeding � These slopes should be sta>>,e IF vegetated and care is used to prevent r L, +" 1 i i �f surface water from penetrating the slope maces and the sl soils nr:ieC iat`- above the faces. Cut or fill slopes greater than 20 feet high should have stability studies performed as a part or the slope r j sh ui d be construction. Temporary exca tions in the on-site soils stable at an inclination of no sL-n;;� �r' than 1 i .roi:1ed. These will 1 1 i �'. gh l i exposed to the atmospheric steeper temporary slopes -� �a elements for several days. The majority of :he on-site o11'; rir: sui tnh:e for use in co)acted :t fill 1 i tf '-xcapt . 1 of :.C.,.'? ._i 1 ,? :r than 3 i ncnes. f�,;j=i a't':iy f i , t � t^ n; shouldb;- !? r C ted to i.ii.'n'derd Proctor density at optimum l - in 1 i . -- i.o achieve Utt. I _�r s i r;;U1,�t:U:i� content •:lii'... should :a'.. T)i_... -• compaction. Filis should coat bloc„ J'" Excavation in the clays and the 3, c. I :.y of the silty gravels °' o excavating _ iipment C);^w or the. denser be G:Ir1:: with conventional -. I r1d '�!�' aly rF'.` light to gravels and he r;'% ;ri ty 01 the t.;'.tlro k wi l i • oL—.t 'ai re �,' i l i ty tr '.fiches and other rOdrrrdt blasting 4.? 4'r:i•'_v,:a`.:, especially in confined excavations. ADI) l i t CNAL i i'1VES I i GAT i ON This suitable general design and I i `_'i report i:3 r�i"�l ii",'.in"?f'`� and 5i.. �, i'. i -C)" yes d on our present knowledge of the site geology, we do not planning. anticipat.a any unusual problaw3 Froln a gaotechnicoi viewpoint. Because of tha rerratic characteristics of ti .!pper soils with respect to their occurrence, swail potential and compression charactar,;stics, we recommend that a more i -depth investigation for Hocks 3, 4 and 5 or excavation inspections be performed in order to detatmine specific design criteria for individual building foundations. Individual sewage disposal systems test data as part of their d -sign. CHEN AND ASSOCIATES, INC. By -------H,!---- /14-------, i -77- Revieed By Richard C. Her:worth, -P.E. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Bic N \ \ t 1 1 \ \, !1\, , , • ,•,„ • , 4 , \ It /\\ AN. o• 1 \ ,A . , 1 . \/.' '‘ I •-, -----R-17:•: I , \ ( I? „ ,\ ;' I. , 1 \ \ - r rnry-Aqc C. 1i rDAsaJL Liva Flow n!,.!::crns of less than 100 suare Con (Orb). exc6v.ted Dn January 0 :,L.„--=,„,:: ;•, 1,•3; ciri 1 led on k)r I I 6, 1977 (Lads 11 1-,:2„..t.t....H in job N-..--). 14,285) /11 k. tti, ,,.. j, ,..-t"--- • , ..., , 4/ i , , . t / I .. -,,,,„ --.. 6 1 Qc • 1 / • / / / y r _ ( - I i ' ; f r ,t; : 1 • \ ! I LJ ,__ __ ..1___ ... \/ / t / \ / t _ • ,::••: i „ 2' /t ', / / t a• 7. / 1 , 1 '2, 22 • / ' ‘ / / 7\x , / • ,„ , 'f L ''` Pi� UC~2O.0 / 00=90.6 / I ' / / / | / -2O0�8/ LL=]83 P|=|4.7 -200=12 P|=KP /4 / � / / / / / / WC=)|.g DD=\06_6 WC= 15.8 -2OO=6O LL=54.5 P|=12.7 ��. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 Pit WC=10.8 DD=I1G.1 =11.1 DD=i0C.7 -200=94 LL=36H-I P1=14.0 0 12 3 --I 9 TDpsoll, clay, _;ilty, orJanic EE1 d rL ri Cly slihtly s:lndy to s,andy Hth some uvel ,nd cobbles, stiff to very stiff, :toist, t') light bro,:n, oorous. Silt (rtL-ITt-il, scttered mediu! soft, dry, white to pink (,,e,,tthered volcanic Gravel - clean to silty moderate arount of cohb 1 boulders, angular, dense t dense, dry to slight moist, Gr_:,v1 (GM) , scattered amount Of cobbles and icu- 1 r and silt, deh-,-te nink tc, • Basalt, e:ktretrcly ,Pick gray -bro!n. • , hand driva sp 1e (undistdrL Bag sa!ole (disturbed), (1) lcst Fits t.:ere excavated on nuoiy 18, 1978 h a b_tckhoe, (2) free ',.iater as encountered in tast Hts at the time of exctice. (3) = Uater Contant DD = Density (); -200 = Percent PassInq N. 20i) Sieve: LL = Liquid Limit (-A); PI = Plasticity Incit?x = Nonplostic. LOGS c).- TEST PITS F;u. 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 0 1 2 CHEN P,JL) A S 0 C S i i .; 1 4 Noturoi NatuNJI .-.....,' Dry N4oistur44 Uri tt 1 '4,V;I0h 6. OrJritant .. 11,9 p percent c f i I _ .-- I-- r-- , 1 1 r--- :----____ -----_____ i-.....1__ $ ---L, ...4 --1-- 1 1 i 4 T t1 i Ir i i Typ cal 7,-;:.,,pl'e. t,T: _....._ .;1,ity clii Imi-1 1 J Pio 11 . depth 1.17;' "7.1.1.,...r.d....0.111......09.1.40.0.! *%.w........ro......-b.....9.,....2140..........M.ca.............R.... 1 I....,, ... , • '•p c f u .... ,J; Dr ,,r '...; n I i' , I t e2 1 !41 04 j t ;, C 7 .t., ,4 r. •.- Olr:.."lnt -......--1--- 1.... i „ 1 1 , I 1 I i i va 1 1 j.j,.klill:1 ..:]: `...-: 3 ;' ,. 1 n ----- _-----Pr5-4s1,14 cAle .„-.O ,,..:tti)(1.1 , 1 ,....-_. ,,----- i. ._.._— , 1 i 1 + LI LT 4)1 r- y clay I ) P LI 2: 0 r frorll1 Fe zh6.5 9 .2, P Cjt 3 L.: L4 F,,,,yr,fli–Ccli.,,,,olickltion Test ke.-;uits F1[7. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 CHEN A N D SSOCIATES J— Nutt:Toi Dry L1(1,1 Yil.crlt =T.. 106. 1.. pc-,` Not Ur 01 `:,:i 31 shire Contrint ... I 1 .:-.) 2417 c 4 r--T-- e n t 0 I Ex.,...Ainii Dr! or.& cons i.,-.ir t pr -...:;::;rt!. I 1 ; ., _4.f_l__ i_... ' 4 i 1 ..-- ;__-- 1 1 .- 7 ---- .---,--- i-- -r—* 4p'ni, i 1 1 I -4- -.— 1_---- T ij : •:_. (3 i )2. i (2 du C.: --, '.... 0 '4 •!..; t: L : .. - I I . 1 1 1 1". -4 -I - • -----r 1 1 ---- - •-• 4 t ti 7 i ---4 0 . a (iepth 1 3.-0" , p `: s I y .5 i 1 ,-,-, Tycl , sa o --, J ..... elzy fr m ;....i, 1.0 APPLIED PR 1) FT — - -------..........., I . :I Notuf cl Dr i Unit .j. Tiitural 1'tkir.)1AtJ .3 COrl",ielt ,* 11 ..'-7, p• yrcitnt . ( • 1 1,e),:i -: ',..; icin,,ii , 1 .- -4- ..„,„,,, „„,,,,..1 i i I - - - - • ' un I 1 ; ., _4.f_l__ i_... ' 4 i 1 ;__-- 1 1 ----- • •-.L 1_---- T ij : •:_. 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A f3: i5 U — um; A 110.1 pc1 C •1* t •••przr, . ; T- • xplp;;.; L--r-- f --- '/P c. a 's ., o I jr- s' ty clay From ?it 6 -t dth 31E0" A L 1 0 ?R -7 S-e,,;(,!ii-Cc-rlsolidt-iHon Test RJH 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 (-j r- 1. • • cl E: A CHEN AND ASSOCIATS 0. A2»O 4, . . .. No hi.-ri! Dry Unit '.'fl:rjht -e- I j 0 . -7 vf Ni.o.urci 441,0k1r1 f.,orit,4nt -- Ili• 1 p.3rcInt ....0 P.N.. S'...'....... ....' 1 • Nature' Dry Unit W•rt,r.iht m ;•I'r.6 pct Nat. -•o1 tr40,3tur,D Cit -i1 4. 12,5 pb'rcr.trit --- 4 , ) I — L 1 0 T-..— . t- I 1 .1_ •-4,,, ; i 1 I I v Oeitc.,n11 1 11-Iit ioN. .4.- 1 7,...-.coqr.r.--;->ic:::-, tin,..ler c•on, tz-nt. I 1 4 1 1 ",-.... .. ''.••••„.. -----T—prcissuf +- -...t Fare t-3 '41'.tt i it..j. 1 1 !, , .... \-, )--- i , 0 I !,1 san p .. Ty::: • ...-...,1 ,. . r e o- s; 5-,:...n:y 9 i-4 xv d 1 i'rorl ...I. —........;.. — r'; 4, . : o at —,.....— ..--- 0. A2»O 4, . . .. No hi.-ri! 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'-... -.- tr) C-.4 ,,-- > YYJ 0 ),- .pl e- ,--• V-) 4-.) — (7, (.; al 0 •.0 4-) ..- ..t.7. ). -cy ttl tr) .-- c.,:, > 1- (.!.'", C-4 I.,1- C7 ;^ e- _ . ). 4.) 4./, 0 > - .- .. ..,-- 0 V) ,...... :3-- 0 )- -- - - V) > ll 1- .>-. C ,- >, ..,.. ul ::, 0 ›.1 .- .fl CI) 1.0 --.• cs4 -....../- LI J) all CC.: V) . .,-. I 1 I 1t2 1 w...; I )- a 7, 1 - , _..., 1 cr. 1 CON Fiw|t‘: G PRESSURE (PS F) - ----F I II ; I DE'i|Ar0R STRESS (P SF) _ , , ..t. ,- __,1 2.- "LD tx- . ...., i 1 .- 0 _ ,...... 0 1! 1 I 1 PL,4onC/7, L|ti'r |wo[x (V.) (f") i 1 ...,-,;- • n... .r. 4,-,, el .... . _ , 1 , ; 1 a-- , v.-% (,'N •-q,... re', LP, --I" ,..0 • ....—....--1 1 . .. CA....... 0. I ' ... — __,..._. %,0 c,..„, • -1 r"-- "" ...* 0-T .-- — r, 1..,-% c.,1 .-. ..- " ,.a 0 0 — — - 1 mATuRAL 1"; TEST DaPTH MOISTURE HT(FEET) (*/*) ....-. co • • 1...n' ....- co _ — 'L.° . c> ..--- .. t." co - ao • 0 ,..... -1, --, --, - cs; 1 0 r‘ ..9 0 Lf 0, 0 %.1.) a 0 0 0 • r.".4 • 1.0 r". 0 • • 0 , LL ,...... D LAMM JOHN W. ROLD Director COLORADO GEOLOGICAL SURVEY DEPARTMENT OF NATURAL RESOURCES 715 STATE CENTENNIAL BUILDING — 1313 SHERMAN STREET DENVER, COLORADO 80203 PHONE (303) 839.2611 February 3, 1978 Mr. Robert Witkowski Garfield County Planning 2014 Blake Avenue Glenwood Springs, Colorado 81601 Dear Mr. Witkowski: RE: LAKE SPRINGS RANCH SUBDIVISION We have reviewed the Chen and Associates Report on this subdivision (Job No. 14285A Jan. 30, 1978) and find that it has adequately addressed the geology and soils of the site. It appears that the geologic constraints of the site are minimal but that soil conditions are such that individual site specific soil investigations and tests should be required before building permits are issued. With the possiblity of both swelling soils and/or soils that can compress under load when wet being present, this will be very important to assure the long term stability of the structures. If these tests are required, we would have no objection to approval of this proposed subdivision. Sincerely, L. R. Ladwig Engineering Geologist LRL/vt cc: Land Use Commission GEOLOGY STORY OF THE PAST . . . KEY TO THE FUTURE • • • • • • • chen and associates, inc. CONSULTING ENGINEERS SOIL t FOUNDATION 96 S. ZUNI • DENVER, COLORADO 80223 • 303/744-7105 ENGINEERING 1924 EAST FIRST STREET • CASPER, WYOMING 82601 • 307/234-2126 ENGINEERING GEOLOGY AND PRELIMINARY SUBSOIL INVESTIGATION FOR PROPOSED LAKE SPRINGS RANCH SUBDIVISION SECTIONS 32, 33 AND 34, TOWNSHIP 6 SOUTH AND SECTION 4, TOWNSHIP 7 SOUTH, RANGE 88 WEST GARFIELD COUNTY, COLORADO Prepared for: SCARROW & WALKER, INC. P. 0. BOX 460 GLENWOOD SPRINGS, COLORADO 81601 Job No. 14,285A January 30, 1978 • TABLE OF CONTENTS • • • • • • • • • CONCLUSIONS SCOPE 2 PROPOSED DEVELOPMENT 2 SITE CONDITIONS 3 GEOLOGICAL CONDITIONS 3 Bedrock Conditions 4 Soil Conditions 4 Structural Geology 4 SUBSOIL CONDITIONS 5 GEOLOGIC HAZARDS 6 MINERAL RESOURCES 7 FOUNDATION TYPES 7 SITE GRADING 8 ADDITIONAL INVESTIGATION 8 FIG. 1 - LOCATION OF TEST HOLES AND PITS AND SURFICIAL GEOLOGY MAP FIG. 2 - LOGS OF TEST PITS FIGS. 3 through 6 - SWELL -CONSOLIDATION TEST RESULTS FIG. 7 - GRADATION TEST RESULTS TABLE 1 - SUMMARY OF LABORATORY TEST RESULTS Val (1) CONCLUSIONS The proposed subdivision development is feasible from an engineer- ing geology and subsoil point of view. (2) There are no geologic hazards nor commercial mineral deposits which would render the project unsafe, infeasible or undesirable. (3) Foundation types in Block 1 should consist of pad and grade beam construction as recommended in our original report (Job No. 14,285 dated April 6, 1977). Spread footing foundations occasionally utilizing minimum dead load pressures are generally suitable for residences and duplex residential buildings over the remainder of the site. (4) Additional investigation by subsoil exploration or foundation excavation inspections should be performed in Blocks 3, 4 and 5 to better define subsoil and bedrock conditions and determine proper foundation design parameters at specific building sites. - 2 - SCOPE This report presents the results of an engineering geology and preliminary subsoil investigation for the proposed Lake Springs Ranch Subdivision situated in Sections 32, 33 and 34, T. 6S. and Section 4, T. 7S., R. 88W., Garfield County, Colorado. The report also presents the most probable type building foundations, recommended soil pressure ranges, engineering geologic aspects of the site, general subsoil con- ditions, and other preliminary design information suitable for general planning. The investigation included a field geologic survey and exploration pits. We previously conducted a soil and foundation investigation for Blocks 1 and 2 of the subject subdivision and reported our results under Job No. 14,285 dated April 6, 1977. The results of that investigation and a review of pertinent geological literature were also a part of this investigation. Results of additional percolation tests were reported under our Job No. 15,346 dated October 19, 1977. PROPOSED DEVELOPMENT We understand that the proposed Lake Springs Ranch Subdivision will have approximately 55 lots designated for single-family residences and 7 lots with planned duplex units. It is proposed to supply water from a community water system utilizing wells as the water source. Individual sewage disposal systems are planned for the single-family residential lots. r 3 41 SITE CONDITIONS The Lake Springs Ranch Subdivision as presently platted includes an area of approximately 441.7 acres. The topography at the site is 41 comprised mainly of hilly ridge and valley relief with several scattered knobs or topographically high points occurring along the western portion of the site. The ground surface at the site ranges from Elevation 6890 • to 7310 feet above mean sea level. Spring Valley occupies approximately one-quarter of the proposed subdivision on its western end. It forms the low area of elevation within the site. The stream which flows in t Spring Valley originates immediately upstream of a small pond in the south-central portion of the site and flows generally northwesterly. The remaining drainages are intermittent and show no indication of recent erosion signifying that they carry very little surface water only during periods of heavy local rain. The relatively small proposed building area to the west of,Spring Valley is of gently to moderately 41 sloping (2% to 11%) ground falling toward the drainage. The much larger portion of the site to the east and southeast of Spring Valley slopes upward from the valley at gentle (5%G) to very steep (30%) slopes which slope in all directions but which generally drain toward Spring Valley. At the time of our geologic survey and latest subsoil investigation, the ground surface was covered with 1 to 2 feet of snow. The vegetation which could be observee!-was scrub oak and sagebrush. 0 GEOLOGICAL CONDITIONS Spring Valley is an upland plateau valley that has been incised into Pleistocene age basalt lava flows which cover a large upland area 4 1 -4 in this region. The site of the proposed Lake Springs Ranch Subdivision extends from Spring Valley on its western end into the hilly terrain to the east of the valley. Bedrock Conditions: The only bedrock exposed on the site consists of scattered outcrops of the Pleistocene age basalt flows. These outcrops are confined to relatively small areas near the tops of the scattered knob features and along one ridge and one road cut which Is immediately outside of the subdivision boundary. The Pennsylvanian to Permian age Maroon formation directly underlies the basalt flows and a portion of the Quaternary soils at the site. The basalt at the site generally consists of highly fractured blocks of extremely hard, competent rock. The joints are filled with clay. Occasionally large amounts of volcanic ash which Is composed of silt are present within the bedrock. Soil Conditions: The Quaternary soils present at the site consist generally of residual and colluvial (slope wash) clay and silty gravel with cobbles and boulders on the upper hilly terrain and clay on the gentler slopes along Spring Valley. Some alluvial soil deposits may be associated with the lower ground elevations along Spring Valley. No subsoil investigation was performed along the Spring Valley flood plain, and the composition of soils in that area are not known by us. Fig. 1 presents a surficial geologic map for the proposed Lake Springs Ranch Subdivision. Structural Geology: Since no outcrops of the Maroon formation were observed at the site, the bedding attitude is not known. However, about • 6 • ash which is predominantly a silt material; and some clay. Some of the gravel soils will consolidate moderately when wetted and loaded but in general will not consolidate as much as the more porous clay. • Bedrock was encountered in Pits` 2 and 3 at 2 to 5 feet deep and consisted of very fractured basalt. No percolation tests were performed as a part of this preliminary • investigation on the remainder of the site exclusive of Blocks 1 and 2. The clay soils over the remainder of the site will have fairly similar percolation properties as those in Blocks 1 and 2 while the lower silty • gravels will possess faster percolation rates. No free water was encountered in the test holes at the time of drilling nor in the backhoe pits at the time of excavation. • Samples of the soils were analyzed for water soluble sulfates. The soils have negligible (less than 0.1%) sulfate content. Special cement types should generally not be required in the concrete to resist deterioration. GEOLOGIC HAZARDS No conditions were observed at the site which would constitute a geologic hazard. We understand that the common area along the Spring Valley stream and the pond at the upper end of the stream are not designated for construction sites. These areas will probably be the only areas that will require construction restraints. No other problems associated with the site geology are anticipated provided that the recommendations for foundations and site grading discussed in this report are followed. MINERAL RESOURCES It is our opinion there are no commercial mineral deposits as defined in the Colorado Open Mining Land Reclamation Act at the site which would be of significant economic or strategic value. FOUNDATION TYPES The foundation types for residences constructed in Blocks 1 and 2 are covered under the Foundation Recommendations section of our original report (Job No. 14,285 dated April 6, 1977) and consist generally of pad and grade beam foundations for Block 1 and spread footings for foundation types in Block 2. In general, the foundation types in Blocks 3, 4 and 5 should consist of moderately loaded spread footings. Maximum allowable soil pressures for the upper sandy clay soils will be on the order of 1,000 to 3,000 psf while maximum soil pressures for the silty gravel will range from 2,000 to 4,000 psf. Some foundations on the denser, stiffer clays may require minimum dead load pressures also. Spread footing foundations on the bedrock generally may be designed for higher bearing pressures. Because of the very- erratic nature of the subsoils with respect to their occurrence and physical properties, individual building sites should have specific subsoil investigations or the foundation excavation should be inspected in order to determine the proper foundation design requirements for the specific structures. • • SITE GRADING Where roads and building sites are constructed within the site, it should be feasible to construct permanent cut and fill Slopes up to 20 feet high at inclinations not exceeding 2:1 horizontal to vertical. These slopes should be stable if vegetated and care is used to prevent surface water from penetrating the slope faces and the subsoils immediately above the faces. Cut or fill slopes greater than 20 feet high should have stability studies performed as a part of the slope design prior to construction. Temporary excavations in the on-site soils should be stable at an inclination of no steeper than 1:1 if well drained. These steeper temporary slopes will slough if exposed to the atmospheric elements for several days. The majority of the on-site soils are suitable for use in compacted fill with the exception of cobbles larger than 8 inches. Roadway fill should be compacted to at- least 95% standard Proctor density at optimum moisture content and should be placed in lifts to achieve uniform compaction. Fills should not block drainages. Excavation in the clays and the majority of the silty gravels can be done with conventional excavating equipment. Some of the denser gravels and the majority of the bedrock will probably require light to moderate blasting to excavate, especially in utility trenches and other confined excavations. ADDITIONAL INVESTIGATION This report is preliminary and suitable for general design and planning. Based on our present knowledge of the site geology, we do not • • • • • • • • • anticipate any unusual problems from a geotechnical viewpoint. Because of the erratic characteristics of the upper soils with respect to their occurrence, swell potential and compression characteristics, we recommend that a more in-depth investigation for Blocks 3, 4 and 5 or excavation inspections be performed in order to determine specific design criteria for individual building foundations. Individual sewage disposal systems should include percolation test data as a part of their design. MJP/bn CHEN AND ASSOCIATES, INC. By f�/_ Reviewed By Oft Richard C. He►P orth, P.E. 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X--< - 1 0 7 O_ 7 01 rt -• O_ - .<0:7 (D U) -< VI VD r* 7-0 - • CHEN AND ASSOCIATES • • • • • • • Compression - % Compression - % 0 1 2 3 0 2 4 6 • 8 10 • 12 0.1 APPLIED PRESSURE - Itsf Natural Dry Unit *sight - pct Natural Moisture Content - 11.9 percent Add ---pressure tiond compression due to wetti under cpnstant ig. 7--------____________.,........„,,,,,,:01 • \\\) • Typical sample of silty clay fron Plt Typ cal sample 6.5' of silty clay from Pit 1 at depth 1.7' 0.1 APPLIED PRESSURE - Itsf 0.1 I o 10 APPLIED PRESSURE - kaf • Swell -Consolidation Test Results #14,285A goo Fig. 3 Notu 01 Dry Unit Weight . 90.6 pct Natu al Moisture Content - 20.0 percent Add ---pressure tiond compression due to wetti under cpnstant ig. \\\) Typical sample of silty clay fron Plt 1 a: depth 6.5' 0.1 I o 10 APPLIED PRESSURE - kaf • Swell -Consolidation Test Results #14,285A goo Fig. 3 • CHEN AND ASSOCIATES • • • • • Compression - % - Expansion 1 0 1 2 0 1 • 0 2 3 • 4 5 Ct '• 6 7 • 8 0.1 APPLIED PRESSURE — kol1 Noturol Dry Unit Weight = 106.6 pcf Natural Moisture Content = 1 1 ,9 porton 1 Exp nsion under compression constart pressure under constant .aeon wetting. pressure due to wettinb. • • Typical sanp e of silty clay frDm sandy Pi: from 3 at depth 3'-0" at depth 3'-0" 0.1 APPLIED PRESSURE — kol1 10 U to APPLIED PRESSURE — k•f • #14,285A Swell -Consolidation Test Results loo Fig. 4 NN al Dry Unit Wo pht = pcf Natu of Mo stur� Content 11 .8 porcent 1 Additional compression under constant pressure due to wettinb. • Typical sample of sandy silt from it 4 at depth 3'-0" 10 U to APPLIED PRESSURE — k•f • #14,285A Swell -Consolidation Test Results loo Fig. 4 • • • • • • • • Compression - % Compression - % - Expansion 0 2 3 4 5 6 7 8 0 1 2 3 • 4 5 • CHEN AND ASSOCIATES 0.1 PRESSURE — kat Natural Dry Unit Weight - pcf Natural Moisture Content - 18.5 percent :---------'."----Nt • Expansion .nd r constant pressure Additional corcrsion upon uiderjconstant ', pressure die to wett i g. 6 Typical sample of si ty, sandy gravel Typical from Pit 5 at _ depth ty clay 5'-o' Pit 1 AA 0.1 PRESSURE — kat 10 10 APPLIED PRESSURE — k�f • Swell-Consoliietion Test Results #14,285A 100 Fig. 5 Noturol Dry Unit Weight - 110.1 pcf Natural Moisture Content - 10.8 percent • Expansion .nd r constant pressure upon weltting. 6 Typical sample of si ty clay from 1 Pit 1 6 at depth 3'-0" 10 10 APPLIED PRESSURE — k�f • Swell-Consoliietion Test Results #14,285A 100 Fig. 5 • CHEN AND ASSOCIATES • • • • • • • Compression - % Compression - % 0 1 2 3 4 5 0 1 2 3 • 4 • 0.1 APPLIED PRESSURE - ksff Natural Dry Unit Weight - 74.6 pcf Natural Moisture Content • 12.5 percent Z---"-- • Additional Nc movement compression upon wetting. under constant\ • pressure due to wetting. • \ . Typical saMple of sl ty clay from Pit 6 at depth 10'-0" Typical sample of si ty, sandy gravel from P1: 6 at depth 5"-0' 0.1 APPLIED PRESSURE - ksff 0.1 10 10 APPLIED PRESSURE - ksf • Swell -Consolidation Test Results #14,285A 100 Fig. 6 Notu of Dry Un,t Weight = 100.7 pcf Natural Moistu a Content • 11 • 1 percent Z---"-- • Nc movement upon wetting. • • Typical saMple of sl ty clay from Pit 6 at depth 10'-0" 0.1 10 10 APPLIED PRESSURE - ksf • Swell -Consolidation Test Results #14,285A 100 Fig. 6 • CHEN AND ASSOCIATES Consulting Soil and Foundation Eng t noon • • • • • • • 1 a W NYOROM[T R ANALYSIS SIEVE ANA�Y_SIS 71 TIME EADIININ ti u 5 STANDARD SERIE3•Io 1 CLEAR SQUARE OPfNS$ glow 301* NMN( • 1NN IMA •100 •100 •30 •40030 • • •• b. Y.' r 1 y S 0 40 4 1 4 4 1 T f 4- r L L 4 r- t f l _1 1 111 1 11 11 r�r[i r 17 t'-Itlr' 1211111[ 00t 000 003 OIS 037 074 10 217 j SRO Ili 33 473 3 3, DIAMETER OF PAR 1 LE IN MILlr ETERS T t I I ItIT H 33, 71t f1 t K CLAY (PLASTIC) TO SILT (4014- PLA1TICI 1 'tot_ j-76D113W 1 COATIIII I FIN[ IIRA}(,L 3RfE c0SSt13 GRAVEL 60 % SAND 28 % SILT ANO CLAY 12 % LIQUID LIMIT % PLASTICITY INDEX NP % SAMPLE OF Slightly silty, FROM Pit 2 at depth 2' - 4' sandy graves 1 3D HYDROM T(� R ANALYSIS To, TINS *EADINit r MIA SOWN ONO • MIN I INN SI(Vf ANA.YSIS u S STANDARD StAIES'1O1 CLEAR SQUARE OKN1Ns3 4300 •100 • 0 40A30 •M f•3 •4 w•r !'r i jt I 70. 1c 001 00t r #14,285A 003 003 30 30 (00 O 10 R r r 11 L'1. L.t r (13_1 iii t111y Till 1 1 1E11r1 011 037 074 1N 337p� !30 �• .1a33 • T• 3 31 i3, 331 Tat 117‘311 DIAMETER OF'PAR TICLe 131 MILLIMETERS CLAY (PLASTIC) TO SILT Mu- PLASTIC) revindDOODLES GRAVEL LIQUID LIMIT SAND SILT AND CLAY PLASTICITY INDEX SAMPLE OF FROM GRADATION TEST RESULTS w 30 100 Fig. 7 cA 2 • Lt CO N AND ASSOCIATES TABLE 1 z U N J N W N W H >- 0 1- 4 0 CD 4 J L 0 cr 4 2 (1) W a } t - J - p y T t0 0 > - N Silty clay 1 >- CU U > .4J - N > (0 L Cr) >- c t0 to > 4r . - N t0 0 > ^ N Basalt -- to > 'O C ft N ; > t0 L LI > CO L ar T C t0 to > 4r — N taAeJb Apues `A3(!S >- t0 U >, 4r — - V) Silty, sandy gravel 1 >• t0 u > N .-. N PERCENT PASSING NO. 200 SIEVE t7O -- '.D •- t31 TRIAXIAL SHEAR TESTS] (.9 W Z C ZDV _NN t` Na Z W '- O Q ua DEVIATOR STRESS (P SF) WATER SOLUBLE SULFATE %) 0 0 0 ATTERBERG LIMITS u K W i i• = L a -. NP M d a, - co M '.O M - tf\ 'D M ›- Cc Cc O >- J ~ < to O W- H O - Z 'D 0 01 VD VD 0 '.D -T h -- 0 -- '.O h N. 0 O NATURAL MOISTURE (•/.) D\ .- -. 20.0 N N O. .- ... OO U\ -- - co a - -- O ..- -- LJ1 co •r. CO 0 ... to N .- t'tl 1 F.. /...U\ 0.. W W W a -- .�. LA 'D 0 ^ -kv i - N 0 M 5.0 0 0 M v.,t1\ i 0 0 f`► 0 M 0 LA f 0 .. 0. I H H W -- I- 0 1 LAKE SPRINGS RANCH DRAINAGE STUDY A RO i Plc. CONSULTING ENGINEERS LAND SURVEYORS CkRR.QW. & WALKER / Inc. • Co suiting Engineers • Land Surveyors 204 8th St. • Glenwood Springs, Colo. 81601 • 303-945.8664 Mr. Duncan Sinnock Foster Petroleum Corporation Carbondale, Colorado 81623 RE: Lake Springs Drainage Study Dear Duncan: 144 West 4th St. • Rifle, Colo. 81650 • 303-625-2740 October 20. 1977 Da ITT t_q77 OCT 21 1977 GARFIELD CO RAM' dit Enclosed are two (2) copies of the drainage study for the Lake Springs Ranch PUD. The design of the drainage facilities was based on the -most recent development plan dated October, 1977, the SCS Drainage Manual and Garfield County regulations. Sheet 3 of 4 indicates where the facilities are to be constructed and the calculation sheets show how the culverts were sized. The report will be included in the formal submittal to Garfield County Planning Department. MSO/hlw enclosures Robert A. Wcrosley Gary S. Berschauer Dennis O. Bradley LeRoy E. Tobler Martin 5. Oldford Raymond 1. Baldwin Robert D. Scarrow — Special Consultant Very truly yours, glaid,z,_4 ago, q/ Martin S. Oldford, P, E. 11 7456 West 5th Ave. Denver. Colo. 80226 3C3/232-6050 LAKE SPRING S RANCH DRAINAGE STUDY OCTOBER 1977 PREPARED BY SCARROW AND WALKER/KKBNA, INC. 204 8TH STREET GLENWOOD SPRINGS, COLORADO I. SUMMARY A drainage study was performed for the Lake Springs Ranch Planned Unit Development located three miles southeast of Glenwood Springs in the Spring Valley Basin. Drainage improvements were sized according to the 10 year storm and flood plains were based on the 100 year storm. It was determined that the major storm runoff is presently routed around the west and south end of the development and eventually enters the lower valley area where a high water table exists. Since this area will be restricted to open space without dwellings and the soil formation shows a high percolation rate the potential damage to property by moving surface water is negligible. Onsite runoff east of County Road 114 from a major storm can be controlled by using the existing pound as a detention area. Excess flow can be controlled by an overflow weir in conjunction with a culvert which will restrict flow to 4 cfs. depending on the headwater elevation. Because a natural spring presently feeds the pond it might be desirable not to restrict the runoff at the pond in which case a larger outlet should be provided. Presently, cost feasibility study is underway to determine whether the springs should be developed as a primary water supply. The area west of the lower valley area is a tributary to a small basin and will drain easterly to the high water table area. A natural detention area presently exists south of the road along the northern boundary of the development and the eventual plan is to contain this standing water in a lined pond if feasible. Adjacent building sites will be considerably above this low area and will not be affected by the 100 year storm runoff. Culverts have been placed at all road crossings as shown on sheet 3 of 4 to accomodate the 10 year runoff. Final design of the roads will allow the culverts to be more accurately placed at low points and headwater elevations will determine actual flow capacities. For purposes of sizing the culvets the HW/D ratio was assumed to be 2.0. II. LOCATION AND DESCRIPTION OF PROPERTY. Lake Springs Ranch is located in the center of the Spring Valley Basin about three miles Southeast of Glenwood Springs in Section 4, Township 7 South, Range 88 West and Sections 32 and 34, Township 6 South, Range 88 West at elevations ranging from 6,900 to 7,300 feet above sea -level. The extreme eastern end of the development lies within the lower reaches of a sub -basin 2,550 acres in size and originating at 9,300 feet in elevation. Aspen and conifer growth occurs at the higher elevations with scrub oak and sagebrush over most of the lower area. The area east of County Road 114 drains to two ponds in series just east of the Quigley Ranch and is 160 acres in size. This area has bedrock outdrops and scrub oak and sagebrush ground cover. The lower valley area is part of a 300 acre basin, which terminates in an alluvium soil with a high water table, which is known to drain slowly to the north. This low area is not suitable for building and has been designated for open space. The ground cover consists of hay fields below the irrigation ditch and sagebrush above it. III. DRAINAGE DESIGN CRITERIA. The storm drainage criteria utilized in this study was based on the Soil Conservation Service "Peak Flows in Colorado Manual", which includes Technical Release No. 55 "Urban Hydrology for Small Watersheds", dated March 1977. Storm precipitations derived fro the study were obtained from storm isopluvial maps for 10 year and 100 year storms presented in the SCS manual. Peak flows in the developed condition will remain nearly indentical to the undeveloped, because of the low density (1 unit per 5 acres) and the large amount of undisturbed open space (25% or 110 acres). The method for calculating runoff involves measuring the individual basins, identifying the soil groups and vegetative cover, calculating the time of concentration based on length of each water shed and average ground slope. It was assumed that all defined channels in the upper reaches of the basins would remain natural. The preliminary plat was used along with the USGS quadrangle to define the sub- basins which affect the Lake Springs Ranch Development. Basin 2, although it does not directly drain through any proposed developement, eventually drains to the large open space in the lower meadow and was included for this reason. In areas where minimum flows were noted we have specified 18 inch culverts to comply with Garfield County Specifications. IV. DRAINAGE FACILITY DESIGN. The drainage scheme utilized for the Lake Springs Ranch Development consists of routing the runoff through the five acre lots. Detention is provided in the existing ponds located east of the ranch and in the lower meadow area which has a natural high water table. The majority of runoff originates within the development and will be channeled along road ditches and through several culverts at road crossings. Potential flood plains exist only in the lower meadow due to the nature of the topography. Since this area will be set aside for open space and because the soil formation allows a high percolation rate, there is no concern for flood damage. The extremely flat ground will provide sheet flow which cannot be accurately defined by mapping. r --t Co' JC L Ja c e; --._s Q�d o-/., Sc c7ea. ! l cam..) s ice-, Col t5 -ado , -o. t Mom. c,L. 1 (0-7 00- S,.-, cte s c� ►-• �h a�-t g �-►, A..e-Qf 3 0-F 4 `4. 11.-e so v I ,.,� S Fes- Oil.. 1 a,,. e__ S tt Qurti, 1 4 - west o -( Cau,.-.�, f2o0,01 t 14 . ,. r3as,r, av Q 2_ P►' ecce . ((SO y✓ frecp I�,�-Y sotr9volP 17& i4 c . ay. 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()LA., c1 04 S Q ()_, ma, hyLo-cam.(c 04 cN 44c .4' (TL. 4 C. -IC -5 e rec ram c 12.1 k o is (2,00.7 1 .0 1-e . Lo-L,J -44 ..€ eawe - J • CD C ._,f _ % c2) 5 rki 3. 0 L_ = 2. 8 (.24.52_ 3x0.5 z C6? 1� ���, � 4=�,zs - Cqxc- ) - o•5 gcs,_-:. J - b - /.. ga sem % an eA 6 490 '{c. ay 10 . a1 4 CA) 6 iZ dam'` 7• to -7 0 c 11 o d 5 _ �►-� . S fry a -e alt2c� • 43` Z 1 10!Llkt� = 7D >k 0 •-7-7 o.4 3 = Z3 Ci .> 7o >-O. 77 • ot- ccs... wC0.4-e_d V az,ren Axa 1 s t 51101--t @ npyrin rock( 4- - crue4k fc cr.)-1(2. r/rro d , ., CA-fld-� O C- b o dam s -GSC o s stip (..e s- AA -Ace_ d.2. -.c_ a( a S s o T ..reotAat Get -Ye -4,$ $ S 5'✓ pY-op o se_ d i D -�J �'Q z — o C5 f }e (er P r►, ¢.� .7( /. Ga � 255 . ate- 3. 7g s?,.. �-►�:' 2- P r e /b SID 4. tJe c d Cf) .3 • 0 I2 462 � 7 c. A o.45xSo Fvre_ 5+ 0.'55 x 75 �l L P.e o.d. s U.G ( -fi ►�.c -7000 ' /7 7a $ g71-7 ZZS a Z'� 4.5 t3-7 36. 4: G -t;, 4 o /do t• /i i�ot) Z. 3. I 3?i o Zze f 340b. j. 7 5k✓ • et.A. ,,o -F c p(nP �, 1 0 -7 !D� o.34 Y ZOO. (p /TC 70�'`3.9� x /�o7 g5Z cfs pi 0-1) Q,b = Zoa x3.98 x o-39 - Z76 CA, Coo„ c P %.0 = 2'.a 1.73 1 C4..1 s, of Ger- ���s-ort o�c. . ,� -���► -.at L,n11 e,Le,1 c a ►tet c -173 v wv-o-f ( a,,ct ► ►kl vLeJ2-dccl/al CC CL cc \ o� o� PRECIPITATION IN TENTHS OF AN INCH f &_ Cli LAJ ) 1 1 SOIL t FOUNDATION ellen and associates, inc.' CONSULTING ENGINEERS ° 17136 12 1: w: t i rt 96 S. ZUNI • DENVER, COLORADO 80223 • 3C3/744-7105 ENGINEERING 1924 EAST FIRST STREET • CASPER, WYOMING 82601 • 307/234-2126 SOIL AND FOUNDATION INVESTIGATION FOR LOTS 3 THROUGH 6 AND 9 THROUGH 19 LAKE SPRINGS RANCH SUBDIVISION SECTIONS 32 AND 33, T. 6S, R. 68W GARFIELD COUNTY, COLORADO Prepared for: Srtrz e-reoLE,,\ SCARRJW & WALKER, INC. P. 0. BOX 460 GLENWOOD SPRINGS, COLORADO 81601 Job No. 14,285 April 6, '977 • TABLE OF CONTENTS CONCLUSIONS 1 SCOPE 2 SITE CONDITIONS 2 SUBSOIL CONDITIONS 2 FOUNDATION RECOMMENDATIONS 3 Lots 3 Through 6 3 Lots 9 Through 12 4 FLOOR SLABS 4 SURFACE DRAINAGE 5 WATER SOLUBLE SULFATE 6 LEACH FIELD 6 MISCELLANEOUS 7 FIG. 1 - LOCATION OF EXPLORATORY HOLES FIG. 2 - LOGS OF EXPLORATORY HOLES FIGS. 3 through 7 - SWELL -CONSOLIDATION TEST RESULTS TABLE I - SUMMARY OF LABORATORY TEST RESULTS TABLE 11 - PERCOLATION TEST RESULTS (1) CONCLUSIONS The residences may be founded on spread footings or individual pads and grade beams designed for maximum soil pressure of 2,500 to 5,000 psf. (2) Minimum dead load soil pressures of 500 to 1,500 psf are recommended. (3) The use of oversized leach fields is recommended. - 2 - SCOPE This report presents the results of a soil and foundation investigation for Lots 3 through 6 and 9 through 19 in the Lake Springs Ranch Subdivision located in Sections 32 and 33, T. 6S, R. 77W, -Garfield County, Colorado. The report presents the most desirable and safe type foundation, allowable soil pressures, water table conditions, percolation rates and soil -related design and construction details. SITE CONDITIONS The subdivision is located about 6 miles north of Carbondale on State Highway 110. At the time of our investigation, the site was vacant. Vege- tation consisted of native grasses and weeds with some sagebrush on Lot 19. The lots investigated are separated by Spring Valley Creek, which is in the common area. The ground surface for Lots 3 through 6 slopes down to the east and Lots 9 through 19 slope down to the west. The topography is generally rolling. Maximum slope in the area zoned for construction is on the order of 10%. There is as much as 60 feet drop across some of the 5 -acre lots. SUBSOIL CONDITIONS Subsoil conditions across the site are erratic with respect to soil consistency, density and swell potential. They generally consist of medium stiff to very stiff clay with small amounts of sand and scattered gravel. Lenses with large amounts of gravel were encountered within the clay soil. Weathered claystone bedrock was encountered in Test Hole 5 at 13 foot depth. Generally, the soils encountered in Test Holes 1, 2, and 3 in the vicinity 3 of Lots 9 through 19 consisted of very stiff to medium stiff clay with low swell potential and may consolidate when loaded and wetted, as indicated by the results of the swell -consolidation tests presented on Figs. 3, 4, and 5. The soils encountered to Test Holes 4 and 5 on the west side of the subdlvl- sion in the vicinity of Lots 3 through 6 possess low to moderate swell potential with swelling pressures as high as 10,000 psf. Swell -consolidation test results for these soils are presented on Figs. 5, 6, and 7. No free water was encountered in the test holes at the time of drilling. FOUNDATION RECOMMENDATIONS Lots 3 Through 6: Because of the swell potential of the clays In this area, we believe the most desirable type foundation for the proposed residences is pad and grade beam designed for minimum dead loads. The following design and construction details should be observed. (1) Footings placed on the natural stiff to very stiff clay should be designed for a maximum soil pressure of 5,000 psf and a minimum dead load pressure of 1,500 psf. Under these pressures, we esti- mate that total settlement will be on the order of 1 inch and maximum differential settlement across the proposed residence will be less than 3/4 inch. (2) In order to achieve the recommended minimum dead load pressure, narrow footings or pads and grade beam will be required. When pad and grade beam 1s utilized, a 4 -inch void should be provided below the grade beam between the pads to concentrate foundation loads. (3) Continuous foundation walls should be reinforced top and bottom to span between individual pads and/or span an unsupported length of at least 10 feet. 4 (4) Local soft pockets of soil found in the foundation excavation should be removed and the footings extended to the lower firm soils. Exterior footings should be provided with adequate soil cover above their bearing elevation for frost protection. Lots 9 Through 19: We believe the most desirable and safe type foundation for the proposed residences in these lots is moderately loaded spread foot- ings placed on the upper natural clayey soils. The following design and construction details should be observed: (5) (1) Footings placed on the upper natural clayey soil should be designed for a maximum soil pressure of 2,500 psf and a minimum soil pressure of 500 psf based on dead load only. Under this pressure, we estimate the total settlement will be on the order of 1 inch and maximum dif- ferential settlement across the proposed residence will be less than 3/4 inch. (2) Continuous foundation walls should be reinforced top and bottom to span an unsupported length of at least 10 feet. (3) Local soft pockets of soil found in footing excavations should be removed and the footings extended to lower firm soils. (4) Exterior footings should be provided with adequate soil cover above their bearing elevation for frost protection. FLOOR SLABS The natural soils at the site possess low to moderate swell potential and are capable of damaging slab -on -grade construction by shrinking and heaving should they be subject to change in moisture content. The only positive method of preventing floor movement is the construction of struc- tural floor with a void space beneath such as a crawl space. Provided the 5 owner is aware of the risk of slab -on -grade construction, we recommend the following construction details be observed for slab -on -grade construction: (1) Floor slabs should be separated from all bearing walls and columns with a positive expansion joint. (2) Interior partitions resting on the floor slabs should be provided with a slip Joint, preferably at the bottom, so that in the event the floor slabs move this movement will not be transmitted to the upper structure. This detail is also important for wallboards and door frames. (3) Floor slabs should be provided with control joints to minimize damage due to shrinkage cr eking and they should be reinforced. (4) A 4 -inch free draining gravel layer should be placed beneath the floor slabs. SURFACE DRAINAGE The following drainage precautions should be observed during construc- tion and maintained at all times after the residences have been completed: (1) Excessive wetting or drying of the foundation excavation should be avoided during construction. (2) Backfill around the residences should be moistened and compacted to at least 85% standard Proctor density. (3) The ground surface surrounding the exterior of the residences should be sloped to drain away from the residences in all directions. We recommend a minimum slope of 6 inches in the first 10 feet. (4) Roof downspouts and drains should discharge well beyond the limits of all backfill. 6 (5) Landscaping which requires excessive watering and lawn sprinkler heads should be located at least 10 feet from the foundation walls of the residences. WATER SOLUBLE SULFATE Typical samples of soil at footing depths were tested for water soluble sulfates. The tests indicate 0.06% and 0.01% water soluble sulfate present in the soil. According to published literature, concentrations of this order have a negligible effect. Therefore, no special sulfate -resistant cement is required. LEACH FiELD Five percolation tests were conducted at the locations shown on Fig. 1. In each case, percolation tests were performed approximately 30 feet from the exploratory test holes. The location and logs of the exploratory and percolation test holes are presented on Figs. 1 and 2. Percolation test results are presented In Table I1. The percolation tests were conducted in accordance with the require- ments of the Department of Health, Education and Welfare. No free water was encountered in the test holes at the time of the investigation. Generally, the ground surface slopes down toward the common area on slopes of less than 10;. The results of the five percolation tests averag 52 m nutes per inch. The rTquirement of the Department of Health, Education and Welfare 1s that the percolation rate be 60 minutes per inch or greater. in our investiga- tion, three percolation tests indicated a rate of 60 minutes per inch and two had faster rates of 40 minutes per inch. No trend could be established 7 from these tests of which areas have the more pervious soils. We believe the area is suitable for septic tank leach field systems, however, because of the measured percolation rates, conservative values should be used in designing of the leach fields. We believe the leach fields should be designed for a rate of 60 minutes per inch. The use of oversized leach fields should be considered. MISCELLANEOUS Our exploratory borings were spaced as closely as feasible in order to obtain a comprehensive picture of subsoil conditions; however, erratic soil conditions may occur between test holes. If such conditions are found to be exposed in the excavations, it Is advisable that we be notified to inspect the foundation excavation. Even by concentrating foundation loads and well designed foundation systems, the possibility of foundation heave will still exist in the event the expansive subsoils become excessively wetted. Ps -O E. 84 h A�� S�v Ar O . .»'5�t-; es , i . r t� P.• 9 • 0 . i;°., . 7524 • .', .•0 B CNEN AND ASSOCIATES, INC. Reviewed By DEB/med Donald ressler, P. E. Richard . 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(D c. -• a' 7- v) u) -• -1 -s - In n 9 O •< 3 ▪ m - a (D rt 5 n - -1 O 3 a - (D to 0 a - 7 n d -1 rr ut G a r) 7- rt -1 O 1 a - -(D C rt - O 7 to C rt S to rt . r m NJ C) CD u) O m DEPTH - FEET 1 1 1 1] 1—T f 1 1 1 1 I v, O O • • 0 to S n \ \ \ 0 O rt 7 - - 0 -- O t W ON - -. - 00 -' - N OOON t.0 +"N ON• ,� • w O N w •g- \ N.) • \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ • \ \ \ N ■ \ \ \ U\ \ \ \ U\ \ \ \ 0 -1 - (D (D rt N 0 -1 -- CD CD u) rt \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ u w \ N. •r V1 c (n C V1 7 -• a (D -1 CT (D (D — l! 7 Cl. O rt -. C N rt ul 1 0- 0 o a i O (D rt < a -n a 0 0 C+ re 1 - 1 7- - - C) a LC) C, < C, < 1 1•-•:: IA -< (D - - • (I. N u, n CD 4- < `< rT rr Q: 1 ✓ r O (D -• 0 -• rt (n 7" 1 to 7 -(1 rt (D U n T () "h (1) O Co- 1 -. u) C 3 cr S (D rt 7 7-o 1 (D (/1 a S a - O a "0 (D 1 - (.C1 - - S• 7 3 (.7 '1 C. (D G • 0 S co .1 1 7 rt < l.1 — 1 - — (D (1) N - 1 • (D 0 - Cr u - O yr O 7 0 ▪ (D -•-C O - 3 to 7 7' - . Q' -h rt t.0 rt (� -• O 7 - ti) to D - 7 rr rt O • (7 (D 0 - -t, 0 -< W V l n (0 O �. C. 0 rt *1 - : -• O Ci N.) __o < rt M.- lD -h - u7 .7 S 1 1 - U) 3 0 `< 3 C) 7 0 — 2 G - 0 C, - - 7 n C, (n a 0 re 1 O -• 0 7 (7 C rt S (n 0- u) 0 c) rt - -- 0 O -• a, T In -< 3 -h CJ • 7 rt a (1 0 r- 3.2@M sayDU! nd01,1801dX3 saleaipu! rt N o O Cl 0 0 1 (D II it (D - -r. J r -t (n 1 n O C (D S S 1 c) Q) (D 0 `< rt re -• • (D O 1 rt n CD (n (D S rt 7 (7 (D (D (D ▪ t to 0 , rt (D -• 7 re (D 1 rr rt -• 1 (D -< CD 3 7 (D u) n rt O 1 O 0 N 7 -• n — -n 7 rr - -n a O • 7 (D • -• 1 c c a —• 7 O — rt c - (D L 7 -• 1 7 (D -h (n a —n, (a - n 7 S 7 - re rT 0 C O F - O - (D (D - X 1 lD 13 v - n v O c 1 (0 rt 1 rt O S 1 DEPTH - FEET m Iv O m 1 1 1 1 1 1 1 1 0 0 V1 O O O Cl II II \ O W J • • \ N 0 n 11 II \ O CA ON• • \ \ \ \ _ \ \ '; \ -\ \ \ \ \ \-_\ \ \ \ 1 \ 1\ 1\ \ \ V1 N V N W 0 V (-1 lc.) 1I 11 N O N N N •A c3 O c O O (1 II II lO N - v G7 N O O \ \ N(.3 0 ( -) Cl 11 11 \ 11 11 \ lD— -N— V W N O — N • O 4:-•W a\ 1 1 1_1 1 1 1 DEPTH - FEET V1 1 1 1 1 1 2 O -1 - CD CD VI rt 0 2 (1 O 0 (D - N rt O. 7 S O -I - (D to rt W 0 (D vl uotae(oa.iad • • o ti R r.n Luke Springs Ranch Subdivision r 0 R r 0 rt r 0 rt O H -- (D (D R County Road 1:114 eaav uowwoJ 1- 0 0 rt w r- 0 R lsai uo!Jeio:Jad R • Z r 0 rt w CHEN AND ASSOCIATES f Natural Dry _;^'t Weight - 96.8 Notural Moisture Content - 14,7 *--li--- -- Exp sloriunder constant rests U re Upon wetting. i I I Typical sample of; Silty, calcareot s clay fecim. Hole 1 at depth 4"0". 1 I o. i F P fifESSL.FtE - '[a° i 1! I1� 1~.. _ f I I t ; 1 i- T 0 i i t I I I i— a }—_ 1 {A•di4iiidn�lirarpression under l o I W! �' 1`� -� c•ns ant ifprysLure due, to wetting. 11 _i,' t Y 1 i ; I G 1 ' ~i I 4 r ! v ;,1 11 I+I d I --i i 1 j 1 IH, 1 s 1 � ; l;Ii Typical sar^pl'e bf stilt)t, calcareoJs Cl �frcjri Hole�1 et depth 9'-0". ; ; ; G; 10 , APPLiEr.,' P A1`.. '33U'lit ! - • •f 107.1 1;.7 !I #14,285 CHEN AND ASSOCIATES • , . , ,.._ dd to al a0mpressibn undei ' , , , ont n sure dtAp_.t0wetting:,_,';,, . ; 11 \ , • ; i 1 ; • • 1 ; ! ! ! ! • • 1 i , • I I ‘• • ! H • ; • I , • ! I 1 I 1 • ! ' Typica sa ple cif calcareous, tila_s_121_111:119ole 2 ait depth 4! -0"....', , • • _._ • p,i 1 ! ! ! a, or, .... ,.. ,,-• - 106,4 _ 1 ' t I, I i \ No•,,ro, *•.4, .1, • 4 1 1_1 1 1 i t ' 1 i , , ; I, i • '.: , t - • 1 ' 't . \ i I 1_1___: ------i.------4--- -,„--,4- i -Additional c.Oripression tinder contptant pressure due to ',Jetting. -----1----1--- ,--Ttl"-- - -11----1-• I t I 'I I, It: I ' I ' . ; ' 1,.•; i I i • 1 ' i ! ; ' ; ' ', • ; , • • t I ; ; , • ; • I , . , ; • 7 tl ! , ; ! • ' 4 ! -...---4.- I . ! . ! li!1 I • , 1 1 -- ; ; 1 I I • . ; , . I , . •, _____;_a_;,...,___;.. • _ :,--- ___;.,_...;,_._,... ...__ • , ; . ; , . --t-- • ; ' , ! • , I , , 1 . • s4pleI 1 V Oci,1 sandy 1 layfrOmH01';&,4 tat depth 91r-0". 1 I 11 I 1 0 i • .......---........................—,,,,.. ; o 1 I LLIL: ', c i A4'PLIE0 PRIfiSL,MIE - '-:r0"-!1•1-Corsoltijn -1.-e•l• Re.,, ._ Typica #14,285 Compression - % 2 CHEN AND ASSOCIATES -r • 3 I Natural D'y U-,1* ovs-j1-* = 106.9 c:f Nat,,Jral Mo:stu,s ' 12.8 -4_4 • —Additional 'compression under constant_pressure due to_ wetting. 7_, Typical sample iof sandy, calcareous play from Hole 3 at depth 9'-0". ! , 0.1 , J A * r3 L I E0 PR E SSUt-• r: - ., ;•0 1 •II'ml...••••••••• Na',1 ,), : 3 31 . 4 1 cr, 9 21.6 Exparsion;under constant pres$u1-0 140n wetting. ! I , •,; I , I ! Y--•---4-•-,-- 44 4-- --i- Typlipl sample of fine sandy, calpareovs'clasifrom Hole 4 at , , , i I , , ALI E 0 P allEIlLfWE - I I • I , ! 4-2.- • #14,285 eil-Ccrs,c;r:on Test CHEN AND ASSOCIATES 98.0 Natural Dry Jn'r #4•,,V0 " 4.0 Natur:.l M^!slur• r;art•nt • 2 _ Expansion under constant pressure upon wetting. i l , • !- ;from Hole 4 � c ='Y Typical sample of,fine sand/,cal carious . at depth 9i' -0'I OA p R ES 3 U q -- r-7--•••• T,_r._ ...._--- N t „ _•_ 103.3 13.9 I o , c t i l ! } 1, ;� �I I j' 1 \ I tot p under constant 1 ,Ex ads i uxs i i I 1pr sstire!u,;on wetting. I ! , .1 lyi 1 , I i I_ in 1 I + i VI S 2 \ 1 ; . i i , , HH' _ — i ti I I i i1 tT , I - __I__1_._;._ Typical sample of fine sandy,alcareous tiay!from Hole 5 at depth 4'-0". _ -____._.__a l I; I� A,op......;s c P•tf 37vriC - , st • Fig. u t #14,285 CHEN AND ASSOCIATES Natural Dry U",• Wiujht Natural Moisture Content - 87.0 oc# 33.4 �Ll Expansion Wider pressure ;upon wetting. . —t- constant i Typical sample of .leathered claystone Frori +ole 5 at depth it+' -0". fl.1 . APPLIED PmESSU,7C - 'a�-- . , " - 103.6 'Typ1c I 11 I 11 f1!;�� 1 N�tu I I 1 ii � I — EkpBn- , Iii— s i Oil - — under .. j ' I �~':../ 1' constarvt pressure ,upon wetting. I ` i 1 i l 1 t I I I ; i; 1 , 1 I I i F II� i i 1 1 f I I i 1 1 1 1 stmp)e of f �rje! sandy clay, frpm:Hole' 5 .at depth 9'-0". rl 01 10 1I)5)LIE O C ,J 40 - K a 414,285 , NATURAL NATURAL DRY DEPTH HOLE MOISTURE DENSITY (FE ET) (•i.) CO -- . ; 0 I -I' ; CO I CT) • . / • • ; . VD r•-., CR 'O •C C•4 .-- .-- .-- I 4 ; 0 � • • ; rel en r--. , . , I 1 r-- r-, 1 t-.4 • -.1• re% ; -.1" .- .— , ••-• , • • . • t i I I; 1 i _„,.. t Ii ,• 0.-% �D1 1 • , r C•4 .-- 1 • I I s.,,O i • ..- CV , 0 . cn .- I 1 I e'l .1 C'el — Co") -7/ • • — Cn . C,4 en I 1 / 1 , I I . • ,, I I . . • •I • • ...- I . . . I ' 1 1 1 1 • ._ I / ; I i / HOLE LENGTH OF DEPTH INTERVAL (In.) (Min.) 36.0 35.0 30.0 30.0 30.0 30.0 36.0 39.0 37.0 38.0 t114,2:35 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 35.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0 TABLE 11 PERCOLATION TEST RESULTS WATER DEPTH AT START OF INTERVAL (Inches) WATER DEPTH AT END OF INTERVAL (Inches) DROP IN WATER LEVEL (Inches) AVERAGE PERCOLATION RATE (Min./Inch.) 16.5 14.75 13.0 12.0 11.25 15.0 14.25 13.5 12.75 12.25 15.0 1:,.0 13.25 12.5 12.0 15.75 14.0 12.5 11.25 10.25 15.75 15.0 14.5 14.0 13.5 14.75 13.0 12.0 11.25 10.5 14.25 13.5 12.75 12.25 11.75 14.0 13.25 12.5 12.0 11.5 14.0 12.5 11.25 10.25 9.50 15.0 14.5 14.0 13.5 13.0 1.75 1.75 1.0 0.75 0.75 0.75 0.75 0.75 0.5 0.5 1.0 0.75 0.75 0.5 0.5 . 1.75 1.5 1.25 1.0 0.75 0.75 0.5 0.5 0.5 0.5 40 Min./In. 60 Min./In. 60 Min./In. 40 Min./In. 60 Min./ln.