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HomeMy WebLinkAbout4.0 BOCC Staff Report 11.13.1995BOCC 11/13/95 PROJECT INFORMATION AND STAFF COMMENTS REQUEST: Preliminary Plan for the Cedar Hills Ranch Subdivision. APPLICANT: Norm Clasen (Spring Creek Land Co.) ENGINEER: High Country Engineering; Zancanella & Associates, Inc., Engineering Consultants LOCATION: A tract of land located in the eastern 1/2 of the NE 1/4 of Section 1, T6S R92W and the western 1/4 of the NW 1/4 of Section 6, T6S R91W of the 6th P.M.; approximately two (2) miles northeast of Silt; north of CR 214 (Peach Valley Road). SITE DATA: 77.5 Acres WATER: Shared Wells SEWER: Individual Sewage Disposal Systems (ISDS) ACCESS: Single access from CR 214 EXISTING ZONING: A/R/RD ADJACENT ZONING: North: O/S South - East - West: A/R/RD I. RELATIONSHIP TO THE COMPREHENSIVE PLAN The subject property is located in District C - Rural Areas/Minor Environmental Constraints as designated by the Garfield County Comprehensive Plan's Management Districts Map. H. DESCRIPTION OF THE PROPOSAL A. Site Description: The property is located on the north side of CR 214 in an area where agriculture has been the dominant, historical land use. Several old corrals and dwelling units are located along the frontage of CR 214. The remaining portion of the property is in native vegetation including meadows, grasses, sage, cottonwoods, pinion and juniper. The topography is varied with relief on the property ranging from 5565 feet at its southern boundary (CR 214) up to 5825 feet near the northern edge of the property, a total relief of 260 feet. Slope ranges from slight to steep with some slopes in excess of 25%. The Roseman Ditch traverses the southern and western portions of the property. See vicinity map on page / 1 B. Adjacent Land Uses: The primary activities in the area are predominantly agricultural (farming, ranching) with a number of single family homesites located in the vicinity. BLM owns land directly north of the applicant's property. Development Proposal: The applicant is proposing a twenty (20) lot subdivision of the 77.5 acre development parcel, which is specified to be built in two phases. The size of the lots will vary from 2.1 acres to 5.1 acres, with approximate, net density being 4.3 acres/du. The applicant had an option parcel of 39.9 acres which, if developed at a later time, would have a total of nine (9) lots, ranging in size from 2.3 acres to 7.4 acres; approximate net density would be 4.4 acres/du. It appears the applicant is no longer considering the option parcel and is not a part of this application. See sketch map, page / j . D. Background: A sketch plan application was submitted to staff in March, 1995, and reviewed by the Planning Commission at the April, 1995 meeting. The Preliminary Plan, as presented to staff for the Planning Commission hearing had been adjusted, essentially creating (3) additional lots and realigning and lengthening the interior road. The Plan was adjusted again prior to the Planning Commission hearing, essentially designating two (2) lots as open space, identifying potential building sites, and refinements to the water system. The Plan has since been changed for this hearing, with the addition of an emergency ingress/egress road, the inclusion of a water detention pond (Lot 3), creation of K -turns for emergency vehicles, different phasing scheme, and proposing a gravel surface for roads instead of chip/seal. E. Phasing: Currently, Phase I will consist of Lots 1, 2, 3, 4, 5, 14, 15, 16, 18, 19 and 20. Phase II will consist of 6, 7, 8, 9, 10, 11, 12, 13 and 17. III. REVIEW AGENCY/PUBLIC COMMENTS A. Colorado Division of Water Resources: Stated contracts with West Divide Water Conservancy District would probably be sufficient to mitigate any injury to decreed water rights; cannot comment on the adequacy of the water supply without a more detailed engineering/geotechnical study. See letter attached on pages / 3 •/? B. Garfield County Road and Bridge: Stated concerns about runoff from site affecting CR 214 and CR 262; no specified ROW width on plans; trouble understanding why no traffic study was conducted on CR 214; concerned with traffic speeds and distances on CR 214 in vicinity of proposal. See letter attached on page / . C. Division of Wildlife: Stated property is critical deer habitat; elk are known to frequent the site; noted the plan does not address wildlife and the associated impacts from the development, nor does it specify covenants. DOW requests: property owners be required to kennel dogs; wire fences for pastures be constructed according to DOW specifications; property owners be required to provide their own fencing to protect haystacks; prospective property buyers be advised that the DOW is not liable for game damage to gardens and ornamentals. See letter attached on pages. D. Bureau of Land Management: Concerns regarding access easement to BLM lands possibly creating unauthorized and unwanted uses of public lands which already have access via existing county roads; concerned with potential OHV use by subdivision residents creating unwanted effects on soils, visual quality, vegetation, archeological/paleontological resources; recommends construction of a boundary fence along the applicant's northern boundary as a condition of approval; hunting is allowed on public lands adjacent to the proposed subdivision; coal minerals underlie the proposed subdivision that lies within Section 6 (T6S R92W) under lots 4, 6, 7, 9 and 10, of which all rights are reserved to the United States; concerned project will impact deer winter range. See letter attached on page ,f.../7. E. Garfield County Regulatory Staff: Concerns regarding the conformance of the application to applicable county standards; concerns with proposed water system; concerns regarding the length of the cul-de-sac; concerned with the multiple traffic entrances to CR 214; stated no impact fee in place to mitigate the effects of the rdivisin on roads; concerned with use of ISD systems. See letter attached on page if F. Colorado State Forest Service: Comments regarding wildfire ha steps that can be taken. See letter attached on pages G. Garfield County Planning Commission: Minutes from April 12, d and mitigational 1995 meeting where Sketch Plan was discussed. See minutes attached on pages H. Bookcliff Soil Conservation District: No response, to date. Colorado Geological Survey: Cited concerns regarding drainages on-site which can carry sizeable flood and debris flows during infrequent, heavy rainstorms; noted moderate to severe geological constraints to development; suggested that only the most level terrain be used for building sites; suggested care be taken to design and maintain roads and drainage structures; recommended lining of the on-site irrigation ditch; recommended that all building sites be investigated by a qualified enneer for potential of necessity to be engineered. See letter attached on page Z J. Burning Mountains Fire Protection District: Recommended that, if on-site ponds and access to them are not upgraded, installation of appropriate hydrants on the domestic water system should occur. See letter attached on page 3/37. K. Kenny Frost - Native American Consultant: Gives Native American and cultural clearance as no above ground archeological sites were identified. See letter attached on pages ?3•1;41 . L. Public Service of Colorado: Requests 12 to 15 foot front lot line easements for joint trench facilities; easements given for utility crossing of irrigation ditch; access to Lot 17 must include access and utility easements. See memo attached on page 3r . IV. MAJOR ISSUES AND CONCERNS 1. Roads: The proposal specifies a single, interior cul-de-sac, approximately 4200 feet in length, terminating in a circle with a radius of 50 feet. The creation of the three (3) additional lots and the subsequent realignment of the interior roadway, has increased its length approximately 525 feet from the length specified on the sketch plan (3675 feet). The proposal calls for developing the roadway to two different standards, based on predicted vehicle per day (VPD) estimates. Accepted VPD estimates, generated by the Institute of Transportation Engineers (ITE), predict, for one (1) rural, single family dwelling, an average of ten (10) vehicular trips per day. The initial 2400 feet of the roadway (revised Phase I), which will serve as the only access and egress for all of the interior lots of the subdivision is required, by County Subdivision Regulations, to be built to Rural Access standards, again based upon the VPD estimates. The Rural Access standards and the Proposed Standards are as follows: Rural Access: VPD: 101 to 200; 50 foot ROW; 11 foot lane width; 6 foot shoulder width; 6 foot ditch width; 3% cross slope; 5% shoulder slope; 80 foot curve radius; maximum grade: 10%. Proposed Standards: VPD: 180; 60 foot ROW; 11 foot lane width; 2 foot shoulder width; 6 foot ditch width; 2% cross slope; 2% shoulder slope; greater than 80 foot radius; no greater than 5.1% grade. These roads are now proposed to be gravel surfaced. The remaining 1800 feet of roadway, serving the lots of Phase II, (two lots will have direct frontage and access to CR 214), is being designed to meet semi -primitive standards, more or less. A significant roadcut is proposed for station 36+00 to 39+50, presumably affecting location of driveways accessing lots 11 and 12. Semi -Primitive Standards: VPD: 21 to 100; 40 foot ROW; 8 foot lane width; 2 foot shoulder width; 4 foot ditch width; 2% cross slope chip/seal surface; 5% shoulder slope; 50 foot curve radius; maximum grade: 10%. Proposed Standards: VPD: 90; 60 foot ROW; 8 foot lane width; 2 foot shoulder width; 4 foot ditch width; 2% cross slope chip/seal surface; 2% shoulder slope; 50 foot radius; no greater than 6.4% grade. (At this stage, all roads are proposed to be chip/seal surfaced) These proposed standards appear to be adequate, given predicted VPD counts. The applicant is currently proposing an emergency ingress/egress, built during Phase II, which would create a connection between the upper portion of the interior road and the lower portion. It appears this road would also serve as a driveway for Lots 11 and 17. It is staffs understanding this road will not be used as a common road and, aside from use as a driveway from the upper portion of the interior road, will only be used for emergency access during certain times of the year when possible to do so. It is unclear whether the road will be gated or other impediments used to prohibit access from undesired uses/users. Traffic Study: The original traffic study assessed traffic impacts along CR 262 (Mid - Valley Road) and attempted to extrapolate these results to CR 214. Staff has recently received a traffic study conducted by Road and Bridge in late September, 1995. The applicant's engineer, using the data supplied by Road and Bridge, found that the existing road is capable of carrying the proposed traffic within Level of Service A (the best operational level as defined by the "Highway Capacity Manual"). Evidently, these calculations discovered that at total buildout of this project, peak hour traffic flow would be 85 vehicles per hour (VPH i Level of Service A would continue up to 129 VPH. See letter on pages 36 Al 7. The engineers have identified at least four (4) ditch crossings, along the studied route, where constriction of the travel lanes impedes traffic flow. The applicant has offered to contribute $4000 to the County for these off-site improvements. Potential Runoff: The engineering study attempted to assess the size of the respective drainage basins which could contribute flow to or across the property, but failed to identify the largest basin, located to the west nd northwest. See the Drainage basin Designation Map, attached on page 3 . As can be seen by the Map, drainage basin "A" may not accurately portray the basin as it exists. The applicant is proposing a detention pond located on Lot 3 that would retain water and reduce the amount of flow during a flood event. No provisions have been included addressing the long-term maintenance of this facility. The interior roadway crosses the Roseman Ditch and an easement from the Ditch Company, for this crossing, will be necessary prior to final plat. 2. Water Supply: There are a total of four (4) wells on-site for domestic water. Water for at least 15 of the lots (neglecting the open space lots 2 and 13) will be supplied from a central well. Lot 1 will continue to use an existing well and lots 19 and 20 will share an existing well. If it is later found that the existing wells are insufficient to supply water to these lots, they (lots 1, 19 and 20) will be added to the central system. The proposal does not discuss this possibility and what it might entail. A pump test was conducted June 16, 1995 on the central well to determine the long- term, safe yield of the this well. The static water level was 73.17 feet below the top of the well casing and total depth of the well is 160 ft. After 220 minutes of pumping, the well stabilized for the remainder of the test (17.5 hours). The test was conducted at a pumping rate of 23 GPM and, in the opinion of the engineer conducting the test, 4111, asIP this pumping rate could be sustained indefinitely as the water in the well would remain above the pump intake. Recovery data for the well indicated the well recovered at a rate faster than the drawdown rate. In an effort to determine the adequacy of the well system, the applicant's engineers assumed the development will have the following criteria: 3.5 people per dwelling unit; 100 gallons of water per person, per day; 1000 sq. ft. irrigation of lawn and garden; Based on these assumptions, July is expected to be the peak demand month for water, using an estimated 0.98 acre-feet. These estimates indicate the completed development of 18 units will require a larger instantaneous peak demand than can be provided by the well alone, expected to be 45 GPM. On-site storage will, therefore, be required to adequately supply water during peak demands and water for fire fighting. The engineers recommend the construction of a second well, to provide mechanical reliability to the system, scheduled to come on-line when the subdivision reaches 75% build -out. This phased water system would serve Phase I of the subdivision (11 lots) with fire fighting water coming from an existing pond. Phase II of this development and water system would serve the remaining nine (9) lots and fire fighting water would come from a 60,000 gallon water storage tank located on Lot 9. Annual water usage is estimated to total 9.23 AF/year, when completely developed. It appears this amount is for 20 lots and may be reduced if only 18 lots are to be developed as homesites. Pump Test: The pump test was conducted in late spring, at a time when water was flowing in the Roseman ditch and the applicant's engineer speculated that the fast recovery rate of the well was influenced by water flowing in the ditch and from the nearby seeps. This seems to indicate that, when water is not flowing in the ditch, the water table may be encountered at a lower depth. The physical location of the ditch on the property in question could cause a temporary elevation of the nearby water table affecting the hydraulic characteristics of the tested well. Likewise, the static water level in the tested well may also decrease when water is not flowing in the ditch. If this is the case, the water table will be located deeper in the well and the amount of available drawdown water in the well would decrease accordingly. Staff recommends further pumping tests be conducted at a time when water has been absent from the on- site irrigation ditch (Roseman Ditch) a minimum of sixty (60) days, in order to allow the water table to return to its more -natural level. A transmissivity test has been conducted and indicates that transmissivity is approximately 6700 gallons/day/foot. Water Quality: A water quality analysis was performed; however, a copy of the final analysis was not provided to staff. A cover letter, attached on page indicates high concentrations of sodium and sulfate in the pump -tested el . The applicant's engineer recommends the use of an in-house Reverse Osmosis type water treatment system to adequately remove the dissolved minerals. Augmentation Water: The applicant has received a water allotment contract for augmentation water from West Divide Water Conservancy District and has submitted an augmentation plan to provide a legal, adequate supply of water to the proposed subdivision. The augmentation plan includes four (4) wells, but only one (1) well has been pump tested. It is not clear from the proposal that the existing, individual wells are included in the application or if these are new wells. At a minimum, some proof of the legal right of the existin wells to be used needs to be provided. See water contract attached on pages 3. Sewer: The proposal specifies the use of ISDS for each lot. The Soil Conservation Service has identified three (3) classes of soils, on-site. First, the torriorthents, are chiefly rock outcrops with thin to deep soils over sandstone or shale bedrock. Torriorthents, if deep enough, can be well -drained, if too shallow, percolation rates will be hindered by lack of sufficient soil and permeability of the bedrock. Second, .. d the Olney loams, tend to be deep, well -drained soils. These soils, have moderate restrictions concerning the use of ISDS, chiefly due to slow percolation rates. Finally, the Heldt clay loam soils tend to be deep and well drained also. The Heldt clay loams have severe restriction concerning the use of sanitary facilities, primarily due to the high clay content, causing slow percolation. Given the various types of soils and their relative depths, it may be necessary to require engineered ISD systems. In fact, percolation test data gathered on-site indicates percolation rates that will, most likely, require engineered systems. A total of five (5) test holes were surveyed, yielding the following data, reported in minutes per inch (MPI): #1 Lot 14 #2 Lot 11 #3 Lot 11 #4 Lot 13 #5 Lot 5 80 MPI; 86 MPI; 6 MPI; 68 MPI; 15 MPI. The Colorado Department of Health requires the engineering of ISD systems when percolation rates are quicker than 5 MPI or slower than 60 MPI. As can be seen by the above data, engineered ISD systems for some, if not most of the lots, are indicated. The exact, site specific conditions are not known and a detailed soil analysis will be necessary for each lot. Furthermore, County guidelines regarding setbacks from the existing irrigation ditch will be necessary to protect the water quality of the ditch, especially if it is to remain unlined. 4. Lot Design/Development: The applicant has recently submitted a map which identifies building sites that should meet County regulations regarding slope and ISD placement. See map on page / 2. . It appears the applicant has attempted to designate these sites with regard to solar aspect and visibility. Given the topography of the property, it appears the homesites located on the southeastern portion of the map would be visible from CR 214 and the others will probably not be seen. Driveways and building envelops should be designed in a way to minimize cuts into slopes of excessive degree and should be designed to minimize erosion. It appears the emergency access road will traverse relatively steep terrain, possibly resulting in a visible scar which, given the highly erodible shales on-site, would be susceptible to rapid erosion. 5. Fire Protection: The Burning Mountains Fire Protection District has responded requesting that the two (2) existing ponds within the subdivision be up -graded and one (1) dry hydrant, at least 2.5 inches in diameter, be installed at each pond with an adequate access for fire trucks provided. The District further requests the first dry hydrant be installed before housing construction begins and the second hydrant by the time half the lots are developed. A 60,000 gallon water storage tank is proposed for the development, which could supply up to 500 gallons per minute for two hours for fire fighting purposes, slated to be constructed during Phase II of the development. 6. Zoning: All proposed lots meet the required two (2) acre minimum as specified by the A/R/RD zone district. All building envelopes will be required to adhere to setbacks as specified in Section 3.02 of the Zoning Resolution. 7. Slope: The placement of building envelopes may be difficult when considering slope and ISDS constraints. A map has been presented which identifies building sites which should allow for building and ISDS placement within County regulations. See map on page . State and County regulations specify that no ISD systems are allowed on slopes in excess of 30%. Furthermore, County regulations specify that, for lots of this size, there must be at least one (1) contiguous acre of less than 40% slope. 9. Compatibility With the Comprehensive Plan: Section 4:33 of the Subdivision Regulations requires review of an application based on compatibility with various planning criteria, including the Comprehensive Plan. The following section addresses the compatibility, or lack of compatibility, with the Plan. Agriculture: (Policies: All) The subdivision may have impact on and from adjacent agricultural uses by its potential incompatibility. Impacts from agricultural uses; noise; odor; etc., will be experienced in the subdivision. Housing: (Policies: 2a; 3; 4b; 5; 6) Existing, platted subdivision lots currently exist in the area of the proposed subdivision, with current build -out estimated at an average of 53%. Conventional zoning, not PUD, is being employed. There are no provisions for low and moderate income housing (stated) within the subdivision application information. The subdivision is situated away from incompatible, non- residential uses such as light industry and commercial centers. No building envelopes are specified on the Preliminary Plan, therefore, no information exists as to how the buildings will be designed to use solar aspect or other energy efficient designs. Recreation/Open Space: (Policies: 4) The proposed development includes provisions for access to adjacent BLM lands. Transportation: (Policies: 2; 3; 6; 7; 8) County regulations do not have any provision for off-site improvements to County roads. The applicant is limiting traffic to one intersection. Connections of roads within the subdivision are not consistent with County road plans. Roadway design is targeting a specific, projected traffic load. Roadway design may create congestion in an emergency situation. Water and Sewer Service: (Policies: 1; 2; 3) It is not clear that legal, adequate and dependable water sources exist for this proposal. The development could not feasibly connect to any existing water/sewer system. Soils on-site are constrained in their use for ISDS. Environment: (Policies: 1; 4; 5; 6; 7; 9) There are slopes on the parcel which are in excess of 25%. Mitigation of erosion by development of the property is required. Mitigation of slope, potential rock -fall or mudflow and slow percolation of soil will be necessary. Areas within the proposed development are susceptible to very slow percolation rates. Depending on design of building envelopes, the potential for removal of vegetation and cut and fill activity is high, causing visual degradation. The County will encourage the development of land with minor or no environmental constraints prior to development of areas with moderate or severe constraints. IV. SUGGESTED FINDINGS 1. That proper publication and public notice and posting were provided as required by law for the hearing before the Planning Commission. 2. That the hearing before the Planning Commission was extensive and complete, that all pertinent facts, matters and issues were submitted and that all interested parties were heard at the hearing. 3. That the proposed subdivision of land is in general compliance with the recommendations set forth in the Comprehensive Plan for the unincorporated area of the County. 4. That the proposed subdivision of land conforms to the Garfield County Zoning Resolution. 5. That all data, surveys, analyses, studies, plans and designs as are required by the State of Colorado and Garfield County have been submitted and, in addition, have been found to meet all requirements of the Garfield County Subdivision Regulations. V. RECOMMENDATION Staff recommends REFERRAL BACK TO THE PLANNING COMMISSION for this proposal as, in stars opinion, this proposal has changed substantially from the original Preliminary Plan submittal considered by the Planning Department and the Planning Commission. If the Board feels that all issues and concerns have been adequately addressed and answered by the applicant, then conditional approval, based on the conditions listed below, is advised. 1. That all representations of the applicant, either within the application or stated at the public hearings before the Planning Commission and the Board of County Commissioners shall be considered conditions of approval, unless stated otherwise by the Planning Commission and the Board of County Commissioners. 2. The Homeowner's Association shall be incorporated in accordance with Colorado Revised Statute requirements. The applicant shall prepare and submit a Subdivision Improvements Agreement addressing all on-site improvements, prior to the submittal of a final plat. 4. The applicants shall submit improvement plans for all roads, bridges, utilities, fire protection, improvements, signage and drainage structures prior to the submittal of the final plat. 5. That all proposed utilities shall be placed underground. That all cut slopes created during construction shall be revegetated with native grasses and shrubs with adequate weed control. All revegetation shall be in accordance with the applicant's revegetation plan. Revegetation and landscaping shall be included in the Subdivision Improvements Agreement. In addition, adequate security shall remain in place for a period of two (2) years to guarantee the survival of all plantings. 7. That the applicant shall demonstrate that procedures are established for the maintenance of all roadways and bridges, including snow removal, through the Homeowner's Association. 8. That the applicant shall pay $200 per lot in School Impact Fees prior to the approval of the Final Plat. 9. That the following plat notes shall be included on the Final Plat: a. "The recommendations of the Colorado State Forester and U. S.F. S. wildfire prevention guidelines shall be followed in the construction of all structures." b. "Prior to issuance of a building permit, the owner of each lot shall prepare and submit a soils and foundation report, an I.S.D.S. design, and a grading and drainage plan prepared and certified by a professional engineer. All improvements shall be constructed in accordance with such measures which shall be a condition of the building permit." c. "Certain lots may require pumps to increase residential water pressure. Additionally, it may be necessary for individual reverse osmosis systems installed for each home." 10. An approved augmentation plan showing a legal water supply for the Cedar Hills Ranch Subdivision development shall be submitted to the county. Said augmentation plan, together with the West Divide Water Conservancy District Allotment Contract and the water rights associated with the wells, together with well permits, and shares from the Roseman Ditch shall be transferred by the developer to a homeowner's association which shall have the power and the duty to enforce compliance by lot owners with the terms and conditions of the augmentation plan. Appropriate Protective Covenants shall further require compliance with the terms and conditions of the augmentation plan. 11. That the applicants shall prepare and submit protective covenants, articles of incorporation and other Homeowner's Association documents including by-laws will be submitted for review by the County Attorney prior to the approval of the Final Plat. 12. That the plat and covenants will provide that there will be no resubdivision of the lots. 13. That all roadways shall be constructed in accordance with the design standards in effect at the time of submittal of the Final Plat. 14. The Final Plat shall identify building envelopes that are in conformance with the recommendations of the geotechnical report and less than 40 percent slope. 15. That a plat note requiring staking and certification by a Registered Licensed Surveyor verifying building location within approved envelope. This requirement shall be incorporated into the restrictive covenants. 16. That adequate easements for wells, waterlines and other attendant facilities and utilities shall be provided on the Final Plat. 17. That ten (10) foot perimeter easements on each lot should be provided for utility purposes. 18. The applicant shall provide road signage in accordance with the Uniform Manual of Traffic Control. These should be included in the Subdivision Improvements Agreement. 19. An additional pump test on Cedar Hills well #3 will be conducted in January, 1996, in an effort to further assess the characteristics of the principal well in the shared -well system. This information will be forwarded to the County Planning Department. 20. Prior to the approval of the Final Plat, the applicant shall submit approved plans (by Colorado Department of Health) for the proposed community water system. 21. All requirements of the Road and Bridge Department contained in their memo shall be considered conditions of approval. 22. The applicant should consider woodstove restrictions and further limitations on dogs. 23. Final approval is contingent on receiving a letter of approval from the Burning Mountains Fire Protection District. 24. Final approval contingent on receiving the required easements from the owner(s) of the Roseman Ditch. 25. A well -sharing agreement for Lots 19 and 20 will be provided at final plat for review by the County Attorney. This agreement will further address the addition of these lots into the central water system serving the other lots within the subdivision if, at some time in the future, the existing, shared well can no longer serve these two (2) lots. Furthermore, provisions will be made within this agreement that will allow the inclusion of Lot 1 into the shared water system if, in the future, the existing well can no longer service this lot (Lot 1).