HomeMy WebLinkAbout3.0 Staff Report BOCC 09.21.99BOCC 9t2u99
PROJECT INFORMATION AND STAFF COMMENTS
REQTIEST:
APPLICA}IT:
ENGIITIEERS:
LOCATION:
SITE DATA:
WATER:
SEWER:
ACCESS:
ZONING:
Amended Preliminary Plan for the Los
Amigos PUD filings 6 thru 10
Los Amigos Ranch Partnership
Schmueser Gordon Meyer, lnc.
A parcel of land located in portions of
Sections 35 and 36, T65, R89W;
portions of Sections 31,32 and 33 of
T65, R88W; portions of sections 5
and 6 T7S, R88W of the 6th P.M.:
more pra.ctically described as a tract of
land located approximately two (2)
miles southeast of Glenwood Springs
off of C.R. 114.
1711.68 acres
Central rvater
Central sewer
County Road 114
Planned Unit Development
I. RELATIONSIIIP TO TIM COMPRSHENSIVE PLAN
The PUD is located in the existing subdivision classification for Study Area I of the 1995
Comprehensive Plan. The Plan recognized the original PUD approved and modified in 1981
and 1996.
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II.DESCRIPTION OF THE PROPOSAL
A. Site Description: The property is located south of Glenwood Springs, in the
southwest portion of Spring Valley. Elevations range from 6400 to 7175 feet. The
site is generally situated on the upland portion of a ridge that slopes from the north
to the south to the Roaring Fork river valley approximately 800 ft, with slopes
ranging from 4oh to over 90o%. The steeper slopes have vegetation consisting
primarily of pinion/juniper trees and sagebrush/grasses. The upland area consists of
some fairly gentle rolling terrain, with slopes generally less than 10%. Portions of
the upland area is existing agricultural lands. A vicinity map is shown on the
enclosed plan map.
B. Project Description: The applicant is requesting the amendment offie Preliminary
Plan appror"d Uy Resolution No. 98-30. (See Resolution pgs. q * / e ) The
proposed amendment adds a filing 6,4. to the previously approved Filings 6-10 of the
Los Amigos PUD. The following table summarizes the changes:
Tvoe of Use
Single Family
Rural Residential
Commercial Acres
Open Space Acres
Total Acreage
Filinss 6-10
164
4
0
975.93
t703.06
Filinss 6. 6A-10
t74
4
4.56
936.47
171 1.68
The 4.6 ac. of land identified on the PUD plan a Neighborhood Commercial area was
deleted from the previously approved Preliminary Plan due to it being identified as
"presently non-developable", due to a lack of central sewer being available. The
additional 10 dwelling units were deleted from the last application for the same
reason, even though they were consistent with the approved PIID densities.
All of the lots will be served by the existing central water supply system that
presently has 320,000 gallon storage tank. An additional storage tank will built on
the west end of the project. The application notes that there will be fire flows
ranging from 500 gpm to 1500 gpm for the project. All of the additional lots will
be served by a low pressure central sewer system , except for the four rural lots which
will utilize individual sewage disposal systems (ISDS).
Primary access to the area will be from the extension of the existing private road,
Los Amigos Drive, and then there are seven shorter cul-de-sacs accessing a number
of the proposed lots. Los Amigos drive will be extended almost three miles further
back along the ridge. The cul-de-sacs and loop roads range in lengthjust over 500
2
uI.
ft. to over 15,000 ft. in length.. There are proposed emergency access easements to
adjoining fields, off of some of the longer cul-de-sacs and loops.
RE\IEW AGENCY COMMENTS
1. Division of Water Resources: The Division previously noted that the proposed water
supply appears to be adequate, and injury to decreed water rights will not occur, as
long as the water company operates pursuant to the decreed water rights and plan for
auWenftti7r-:vhich are leased from the Los Amigos Ranch Partnership. (See letter
PES' r t r''t 1
Colorado Department of Public Health and Environment: The department has
verbally indicated that the development of a central sewer for the area is the
preferable method treating sewage in the area.
Roarins Fork School District RE-l: The District has previously determined that the
proposed school site is adequate to meet the land requirements for a school site, as
opposed to paying cash in lieu of land. (See letter pg. / U )
Division of Wildlife: The DOW previously acknowledged that the development has
tried to design around deer and elk ranges, but there is need to recognize that there
are other types of wildlife impacts. Suggestions were made regarding methods for
dealing with other types of wildlife. T!.y recommended predefined building
envelopes for certain lots. (See letter pgs.,0-fl1
Carbondale & Rural Fire Protection District: The District previously noted that
portions of the development are in the Glenwood Springs Fire District and other
areas are in no district. They recommend that the overlapping boundaries be resolved
to allow the Carbondale District to protect the entire project and those portions not
in any district be annexed to the District. They also recommended that the fire
hydrant spacing be modified, which was agreed to by the developer's representative.
The District in a previous letter noted that they will be requiring the developers to
pay impact fees directly to the District, at the time of platting lots. (See letter pg. -Z0- L/ )
Bureau of Land Manags:ment: The BLM had expressed some concerns about the
potential for use conflicts between the public and private land. They have also noted
the need to consider big game movement through the development. There are federal
minerals underlying portions of the develogment, that need to be considered in any
future subdivision action. (See letter pgs. 'z- )
2.
aJ.
4.
5.
6.
7.Colorado State Forest Service: An agency representative previously went on site
with a local fire department representative and the applicant's representative and
concluded that ttre proposed development can be protected from wildfire. A number
of recommendations were made in a prior letter regarding the site improvements,
ridge line setbacks and construction materials for structures. Included with the letter
were the NFPA 299 standards for the Protection of the Life and Property from
Wildfire. A subsequent letter stated that the previous comments are still valid. (See
letters andattachmentspgs. 23 ' ?< )
Wrieht Water Enqineers, Inc.: WWE was hired by the County to assist in the review
of the Los Amigos Ranch Preliminary Plan. They noted a number of issues that
needed to be resolved before the County approved the previous Preliminary Plan..
WWE reviewed the application for Filings 6- 1 0 and noted a number of issues related
to the lots removed from the previous application, the rural lots, drainage and the use
of ISDS for all of the lots. Enclosed is a letter sumlnarizing the WWE response to
the applicant's previous proposats. (See pgs. Zb-'l2a
MAJOR ISSUES AND CONCERNS
A. Zonrng The Los Amigos PUD zone district text and PUD Plan were amended by
Resolution No. 96-34. As a condition of approval for the amendments, the applicant
was required to dedicate at least the equivalent of 25o/o of each subdivision to the Los
Amigos homeowners association. Filings 6-10 is a total of 171 1.68 ac. in size, with
936.47 ac. (55%o) of Open Space.
Filing 6 included lots that had been previously designated "presently non-
developable single-family residential" and an area designated "presently non-
developable neighborhood commercial". It would have been necessary to either
merge the non-developable residential lots into some of the proposed lots or to
amend the PUD to merge the lots with the Open Space. These lots have been added
back into the development, as noted previously. The non-developable neighborhood
commercial needs to be platted as separate lot in the first final plat.
B. Comprehensive Plan Compliance: The 1995 Garfield County Comprehensive Plan
identifies the Los Amigos PUD as an existing subdivision. and the PUD was found
to be in general conformity with the Comprehensive Plan when it was amended in
1996.
C. Soils/Topography: The applicant's geologic report for this portion of the
development "did not identify any geologic conditions or potential geologic hazards
that would prevent development of the site for the intended single family residential
use. The Board of Cotrrty Commissioners required that the following plat note be
placed on all subsequent plats, as a part of the PIID amendment approved:
8.
IV.
D.
"Prior to the issuance of a building permit, the owner of each lot shall prepare and
submit a soils and foundation report, a grading and drainage plan, and a geologically
acceptable building site prepared and certified by a professional engineer. All
improvements shall be constructed in accordance with such engineering
recommendations, which shall be a condition of Los Amigos Ranch Architectural
Control Committee approval and the building permit."
WWE engineers noted in their letter, that RR Lot 3 appears to have a very limited
building lot area, based upon the geologic report. After further discussion with the
applicant, it was agreed that the final plat for RR Lot 3 will include a building
envelope designated by registered professional geotechnical engineer and a plat note
requiring the submittal of foundation design stamped by a professional geotechnical
engineer with the building permit application.
Road/Access: The proposed subdivision is accessed by Los Amigos Drive, which
is being built to minor collector standards and will handle up to 250 single family
dwellings. The applicants have proposed to build Los Amigos Drive as a minor
collector with a 60 ft. row and 12 ft. driving lanes, up to Station 143+15.38. The rest
of Los Amigos Drive will be built to Secondary Access standard with a 60 ft. ROW,
with 11 ft. driving lanes. All other roads will be built to Rural Access standards
with a 50 ft. ROW and 11 ft. wide driving lanes. All of the roads will have a chip
and seal surface.
All roads need to have names assigned to them, that are not used elsewhere in the
County. Staff suggests that the applicants not use "cedar" or "pinion" for any of the
proposed streets names.
Fire Protection: The Carbondale and Rural Fire Department reviewed the project
and stated that the proposed amount of water appeared to be adequate and that the
roads were adequately sized to accommodate emergency services equipment. The
District had asked previously that the fire hydrant spacing be reduced to 500 ft. to
comply with the Uniform Fire Code standards. The revised application was reviewed
by the Fire District and hydrant spacing was agreed to by the developer. Any final
plat application should include a letter from the District approving the hydrant
spacing.
It was also noted that a portion of the development is located in the Glenwood
Springs Rural Fire Protection district and another portion in no district. The
Glenwood Springs section is located on the north end of the development and is only
accessible from CR 114, It has been proposed to deannex the portion of the in the
Glenwood district and annex it to the Carbondale district. The non-district area is
on the east side of the development. Both areas need to be annexed into the
Carbondale Fire District.
E.
F.Water: As a part of the PUD amendment approval, the applicant was required to set
forth the method of transferring the legal ownership and control of the water
distribution facilities and water rights to the Los Amigos Homeowners Association.
An agreement was submitted and approved by the Board of County Commissioners
at the time of Final Plat approval of Filing 5 All new lots will have to be included
in the same homeowners association.
WWE has noted that RR Lots 1-4 are proposed to have individual wells for the
source of domestic water. They expressed concem about the use of wells for RR
Lots 1-3, given the history of wells in the area arrd the proposed use of ISDS by the
lots above the lots. They recommend that the " developer help facilitate the shortest
connection possible to the central water system with easements". Staffconcurs with
the recommendation and would add that the issue needs to be resolved prior to the
approval of a Preliminary Plan by the Board of County Commissioners.
Wastewater: The previous application had all of the residential lots using individual
sewage disposal systems (ISDS). As a condition of approval of the previous
Preliminary Plan contained in Resolution No. 98-30, requiring that the "method of
sewage disposal shall be a low pressure central sewage disposal system of a type
similar to that proposed by the Garfield County engineer,..." The application
includes such a system.
Road Impacts: The applicant was required to make certain improvements to the
intersection of the subdivision's main entrance and County Road 114 and to pay a
road impact fee at the time of final plat. The impact fee is to be based on the most
current analysis of the cost of improvements to 114 from the Auburn Ridge
apartments road intersection to Highway 82 and an analysis of the proportionate
share of those expenses attributed to the Los Amigos PUD for those road
improvements. The only study available dealing with those specific parameters, is
the analysis submitted by the applicant's engineer at the PUD approval. The
subsequent analysis done by the County used a different basis for establishing and
cannot be used to establish a road impact fee for this PUD. The PUD approval
established a $200/lot road impact fee for this development.
Drainage: WWE noted that the application had noted some minor increase the
amount of surface runoff from the project, but had not proposed any mitigation for
the increases. The applicants have reviewed the issue again and recommended on
site detention of the surface runoff in certain drainages. There is no calculation of
the amount of detention area is required, based upon calculations. The subdivision
regulations require the calculation of the runoff and inclusion ofthe calculations in
G.
F.
G.
6
G.
the application. WWE had noted that the proposed locations appear to be correct,
but there is a need for the calculations prior to the submittal of a final plat.
Additional calculations were submiued by the applicant and found to be acceptable
by WWE.
PUD Requirements : The applicant was required to include the following plat notes
on any final plat:
Prior to the issuance of a building permit, the owner of each lot shall prepare
and submit a soils and foundation report, a grading and drainage plan, and a
geologically acceptable building site prepared and certified by a professional
engineer. All improvements shall be constructed in accordance with such
engineering recommendations, which shall be a condition of Los Amigos
Ranch Architectural Control Committee approval and the building permit.
The owner of each lot utilizing an individual sewage disposal system (ISDS)
shall obtain site specific percolation tests to determine whether a standard
septic system is acceptable or an engineered system is appropriate or
required. Each ISDS shall be designed to minimize tree removal and changes
to the natural contours of the land.
The recommendations of the Colorado State Forester and the Fire Chief as
set forth in the Supplemental Declarations dated September 28,1992 et. seq.
shall be followed in the construction of all structures.
All lots designated to lie within the Spring Valley Sanitation District shall
obtain central sewer service pursuant to agreement with the District.
Open hearth solid-fuel burning fireplaces are not allowed.
Each dwelling unit is allowed one dog.
RECOMMENDED FINDINGS:
A. That the proper publication, public notice and posting were provided as required by
law for the hearing before the Board of County Commissioners; and
B. That the hearing before the Board of Courty Commissioners was extensive and
complete, that all pertinent facts, matters and issues were submitted and that all
interested parties were heard atthat hearing; and
1.
2.
).
4.
5.
6.
IIL
7
D.
E.
C. 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; and
That the proposed subdivision of land conforms to the Garfield County Zoning
Resolution; and
That all data, surveys, analysis, 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.
RECOMMENDATION
The Planning Commission recommended approval of the proposed Amended Los Amigos
Ranch , Filings 6-10, subject to the following conditions:
All representations of the applicant, either within the application or stated at the
public hearings before the Planning Commission shall be considered conditions of
approval unless otherwise stated by the Planning Commission.
Prior to submittal of a Final Plat, all property shall be annexed into the Carbondale
and Rural Fire Protection District that is not presently in the District.
All conditions of approval contained in Resolution No. 98-30, shall be considered
conditions of approval, except for the removal of conditions #5 and #6 and the
modification of Condition #13 to read as follows:
13. The Rural Residential lots shall be allowed
disposal systems.
to utilize individual sewage
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IV.
1.
2.
J.
8
STATE OF COLORADO )
)ss
County of Garfield )
At a special meeting of the Board of County commissioners for Garfield county, colorado,held in the commissioners' Meeting Room, Garfield corurty courthouse, in Glenwood Springs onwednesday , the z7th-of May A.D. 19 9g , there were present:
, Commissioner Chairman
, Commissioner
John Martin Commissioner
County Attomey
, Clerk of the Board
when the following proceedings, among others were had and done, to-wit:
RESOLUTION NO. q B= ? o
A RESOLUTION CONCERNED \MITH TIIE APPROVAL OF A PRELIMINARY PLAN FOR TI{E LOSAMIGOS RANCH, FILINGS 6-10 SUBDryISION.
WHEREAS, Los Amigos Ranch Partnership filed an application with the Board of Countycommissioners of Garfield county for approval of a Preliminary iian for the Los Amigos Ranch Filings6-10 Subdivision; and
WIIEREAS, the Garfield county Planning Commission reviewed the Los Amigos Ranch Filings6- l0 Preliminary Plan application and recommended conditional approval to the Board of countyCommissioners; and
WHEREAS, based on the material submitted by the applicant, the recommendation of the planning
commission and the comments of the Garfield county Planning Department, this Board finds as follows:
1' That proper publication, public notice and posting was provided as required by law for thehearings before the Planning Commission and Board oiCo*ty Commissioners.
2' That the hearings before the Planning Commission and Board of County Commissionerswere extensive and complete, that all pertinent facts, matters and issues were submitted andthat all interested parties were heard at that hearings.
3' That the Garfield County Planning Commission recommended conditional approval of thePreliminary plan.
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4.
5.
!'::'3 3'l11a'3t r. oo GRRFTELD couNTy co
Subject to the conditions set herein, the proposed subdivision of land is in compliance withthe recommendations set forth in the Comprehensive Plan for the unincorporatei area of theCounty.
With exceptions set forth below, all data, suryeys, analyzes, studies, plans and designs asrequired by the State of Colorado and Garfield County have been submitted, reviewed, andfound to meet all sound planning and engineering iequirements of the Garfield CountySubdivision Regulations. The requirements of Resolution No. 96-67,paragraph 5. have notbeen met as follows:
6.
7.
A' In regard to environmental and health impacts the Board determined that theevidence demonstrated at least the following:
1' Any proposed ISD system to be utilized in this subdivision would require
close monitoring and a high level of maintenance. Failure to achieve strict
compliance would result in system failure and potential contamination of
ground water. Neither the County, nor the developer can adequately assure
strict compliance.
2 The Board could not find adequate evidence of a monitoring plan that would
assure no contamination to ground water.
3' The applicant did not adequately demonstrate that geologic conditions, which
may include shallow surface soils, fractured bedrock and existing water
tables, were suitable for ISD systems.
4' After review of the environmental and health impacts, demonstrated by the
totality of the information presented to the Board, the Board determined that
the applicant shall not be allowed to service the remaining lots within Los
Amigos Ranch PIID with ISD systems, other than as set f;fth in paragraph
13 below.
B' The Colorado Department of Health and Environment has not made an actualaffirmative recommendation of approval as required by 30-2g-136 (1)(g) cRS,aithough the Board recognizes that by 30-25-b6 (2) CRS *. .nurt treat thatdepartmentt silence as a favorable recommendation under the statutes.
Subject to the conditions set forth herein, the proposed subdivision of land conforms to the
Garfi eld County Zoning Resolution.
For the reasons set forth herein, the proposed subdivision is in the best interest of the health,
safety, morals, convenience, order, prosperity and welfare of the citizens of Garfield County.
40_
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525809 05/27/1998 03:54P 81469 P615 ll RLSDORF3 of 5 R O.OO O O.OO GRRFIELD COUNTY C0
NOW, TI{EREFORE, BE IT RESOLVED that the Preliminary Plan of Los Amigos Ranch Filings
6-10 Subdivision for the following described utincorporated area of Garfield County be approved with the
following conditions:
5.
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.
The Homeowner's Association shall be included as a part of the Los Amigos HOA and
incorporated into it in accordance with the Colorado Revised Statutes. The 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.
The applicant shall pay $200 per lot in Road Impact Fees prior to the approval of the Final
Plat.
All recommendations of the Colorado State Forest Service regarding wildfire protection will
be incorporated into the covenants, including the design guidelines identified in the NFPA
299 standards for the Protection of the Life and Property from wildfire.
The residential lots in Filing No. 6, designated as "presently non-developable single family"
lots will either be merged with adjoining lots in the filing or a request for minor amendment
to the PIID Plan will be made to merge the lots in question with the Open Space designation
in the PUD. The lot shown as "presently non-developable neighborhood commercial" will
be included on the Filing 6 final plat and noted as a lot subject to further subdivision and that
no development will occur on the lot until a Preliminary Plan for the lot is submitted and
approved by the Board of County Commissioners.
That a minor modification of the PUD Plan is hereby approved by the Board of County
Commissioners as a part of the approval of the Preliminary Plan to accommodate the
mergers set forth in paragraph 5. above.
The RR Lots 1-3 shall include easements for water and access purposes that are the shortest
connection possible consistent with sound environmental conditions and constraints, on the
applicable plat. Further that RR Lot 3 shall have a building envelope designated on the
appropriate plat, that has been identified as being buildable by a registered geotechnical
engineer.
The applicant is required to include the following plat notes on any final plat:
A. Prior to the issuance of a building permit, the owner of each lot shall prepare and
submit a soils and foundation repoft, a grading and drainage plan, and a geologically
acceptable building site prepared and certified by a professional engineer. All
1.
2.
1J.
6.
1.
8.
- / /-
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improvements shall be constructed in accordance with such
recommendations, which shall be a condition of Los Amigos Ranch
Control Committee approval and the building permit.
engineering
Architectural
B.
C.
The owner of each lot utilizing an individual sewage disposal system (ISDS) shall
obtain site specific percolation tests to determine whether a standard septic system
is acceptable or an engineered system is appropriate or required. Each ISDS shall be
designed to minimize tree removal and changes to the natural contours of the land.
The recommendations of the Colorado State Forester and the Fire Chief as set forth
in the Supplemental Declarations dated September 28,lgg2et. seq. shall be followed
in the construotion of all structures.
D. All lots designated to lie within the Spring Valley Sanitation District shall obtain
central sewer service pursuant to agreement with the District.
E. Open hearth solid-fuel buming fireplaces are not allowed.
F. Each dwelling unit is allowed one dog.
H. The BLM has reserved all mineral interests on the property and there may be mineral
extraction activities on the property in association with these mineral rights.
A new phasing plan, consistent with Section 4:34 of the Garfield County Subdivision
Regulations, as submitted by the applicant, has been accepted by the Board of County
Commissioners and incorporated into the approval ofthe Preliminary Plan, during the public
hearing
That the applicant comply with all ofthe recommendations of the Division of Wildlife noted
in a letter dated3/lll98.
At the time of each Final Plat, properly formatted computer disks will be provided to the
County that will transfer the plat information to the Coturty Assessor's CAD system and the
County Geographic lnformation System
As a result of the determination of this Board set forth in Findings paragraph 5. (See above),
as a condition of approval the method of sewage disposal shall be u lo* pressure central
sewage disposal system of a type similar to that proposed by the Garf,reld County Engineer,
with the cost of the central sewage line to be bome by the developer.
The Rural Residential lots shall be allowed to utilize individual sewage disposal systems,
provided a ground water monitoring system is approved by the Couniy Engineer prior toFinal Plat approval and the monitoring plan will be the responsibility of the Los Amigos
Ranch Homeowners Association.
9.
10.
11.
t2.
13.
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s25809 05/27/1998 03r54P 81069 P617 ll RLSDORF
5 of 5 R O.OO O O.OO GRRFIELD COUNTY C0
14. The monitoring and eradication of all noxious weeds shall be the responsibility of the Los
Amigos Ranch Homeowners Association.
Dated this 2 7 day of Maw , A.D. 1g qa
GARFIELD COUNTY BOARD OF
COMMIS SIONERS, GARFIELD COUNTY,
COLORADO
Upon motion duly made and seconded the
Marian Smith
foregoing Resolution was adopted by the following vote:
, Aye
Larry McCown , Aye
John Martin , Aye
STATE OF COLORADO
County of Garfield
I,County Clerk and ex-officio Clerk of the Board of County
Commissioners in and for the Corurty and State aforesaid do hereby certifu that the annexed and foregoing
Resolution is truly copied from the Records of the Proceeding of the Board of County Commissioners for
said Garfield County, now in my office.
)
)ss
)
IN WITNESS WHEREOF, I
Glenwood Springs, this _ day of
have hereunto set my hand and affixed the seal of said County, at
A.D. 19_.
County Clerk and ex-officio Clerk of the Board of County Commissioners
Chairman
-/3 -
STATE OF COLCTUDC
OFFICE OF THE STATE ENGINEER
Division of Water Resources
Department of Natural Resources
'1313 Sherman Street, Room 818
Denver, Colorado 80203
Phone (303) 866-3581
FAX (303) 866-35B9
February 18, 1998
Roy Romer
Covemor
James S. Lochhead
Executive Director
Hal D. Simpson
State EngineetMr. Mark Bean
Garfield County Planning Department
109 8th Street, Suite 303
Glenwood Springs, CO 81601
RE:Los Amigos Ranch PUD, Filings 6,7, 8, I &10
Sections 5 & 6, T7S, R88W, 6th P.M.
Sections 31 & 32, TOS, R88W,6th P.M.
Sections 35 & 36, TGS, R89W,6th P.M.
Water Division 5, Water District 38
Dear Mr. Bean:
We have reviewed the subject preliminary plan, which proposes to create a total of 168
single-family dwellings on 727 .13 acres located in filings 6 through 10. The proposed water supply
is to be provided through a central system operated by the Red Canyon Water Company
(Company). A letter of commitment from the Company, dated February 9, 1996, was included in
the submittal material. We previously commented on a proposal which included the subject
development in our letter of January 26, 1998. The only difference between the submittals
appears to be that Filing 5A has been omitted and that portions of Filings 10 and'11 have been
included in Filing 6 as open space and presently nondevelopable parcels. The net effect has
been a reduction of single-family dwellings by ten and elimination of the commercial development.
Therefore, our previous comments still apply, and are repeated below.
A letter from Mr. Loyal E- Leavenworth, dated November 24, 1997, indicated that to date
final plat approvals within the Los Amigos Ranch PUD totals 47 single family lots and 96 multi-
family units. This proposal results in a total of 321 units. At full buildout, the PUD is projected to
include a total of 327 single-family homes and 96 apartments. Total annual water demand at
buildout will be 194 acre-feet, and consumptive use will be approximately 68 acre-feet. The 68
acre-feet of depletions are to be augmented pursuant to a plan for augmentation, which was
approved by the Division 5 Water Court in case no. 87CW155.
The PUD is currently supplied by two wells, known as the Rancho Los Amigos Well No. 6
(permit no. 40906-F) and the Los Amigos Ranch Well No. 5 (permit no. 18147). Well No. 6 is
decreed in Division 5 Water Court case nos. W-3873, W-3893, and 94CW36 for 300 gallons per
minute for municipal use. Well No. 5 is decreed in case no. W-2156 for 300 gallons per minute for
municipal, commercial, domestic and industnal uses. The water rights used to supply this PUD are
owned by the Los Amigos Ranch Partnership, are leased to the Company for a period of 50 years
with a 40-year renewal option.
'14-
Mr. Mark Bean
February 18,1998
A report dated November 17, 1997, prepared by Schmueser Gordon Meyer, lnc., indicated
that Well No. 5 had been test pumped at 110 gallons per minute, and Well No. 6 had been test
pumped at 400 gallons per minute. The combined yield of the two wells exceeds the estimated
required peak day pumping rate at buildout of 335 gallons per minute. \
Pursuant to Section 30-28-136(1XhXl), C.R.S., the proposed water supply appears
adequate, and injury to decreed water rights will not occur, as long as the Company operates
pursuant to the decreed water rights and plan for augmentation, which are leased from the Los
Amigos Ranch Partnership.
Should you have further questions or @mments regarding the water supply for this project,
please contact Craig Lis at this office.
Sincerely,
Steve Lautenschlager
Assistant State Engineer
SPUCMULoS Amigos Ranch Flag 6-1O.doc
Orlyn Bell, Division Engineer
Joe Bergquist, Water Commissioner
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Fcbruary 23. 1998
Mark Bean
Garficld County Ptanning Department
109 8th Strect, Suite 303 .
Glcnwood Springs, CO 81601
llc: Los Amigor Rrnch - Filingr 6 through l0
Dear Mark:
Los Antigos Ranclt ltas included a l3 acre schoolsite in its plan. This mccts thc District's
rcquircmcnts for land dcdicotion for a subdivision of ttris size. Thank you for thc opportunity to
provide cornrnetlts on this preliminary plan. Pleasc don't lrcsitatc to call if you havl any
questions.
*wW
Financc Dircctor
-l 6-
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STATE OF COLORADO
Roy Romer, Governor
DEPARTMENT OF NATI]RAL RESOURCES
DIYISION OF WILDLIFE
AN EQUAL OPPORTTJNITY EMPLOYER
John Mumma, Director
6060 Broadwav
Dcnvcr, Colorado EO2l6
Telephone: (303) 297 - | 192
50633 Highway 6 &24
Glenwood Springs, CO 81601
303-945-7228
e
ForlYildlife-
For People
qAff€LU
January 5, 1998
Mark Bean
Garfield County Planning Deparrnent
109 8th Street, Suite 303
Glenwood Springs, CO 81601
RE: Comments on Los Amigos Ranch, Filings 5A-11
Dear Mark,
While Los Amigos Ranch has gone a long way in tryrng o avoid severe deer and elk winter ranges in
their development, the Division of Wildlife would like to make some recommendations to try and improve the
ability of homeowners to enjoy wildlife on their property, help avoid human/wildlife conflicts and help
migration of wildlife onto severe winter ranges reserved by Los Amigos Ranch.
First, the wildlife statement included in ttre development plan by Greg Boecker gives a general list of the
wildlife located on or near the devel,cpment. It would be helpful to all new owners of this property for [,os
Amigos Ranch or the developer to provide a small brochure or leaflet advising what wildlife species may be
encountered and how to avoid potential wildlife related problems. Many owners moving into the area may
not be aware of the possibiliry of coy'otes kilhng pets, bears searching out food inside vehicles and building,
mslrnein lion sightings in areas where their children may be playrng and damage to ornamentals by deer and
elk. An informed owner has the abiliry to avoid or reduce these problems.
Secordly, while this rarrch is corsidered as less than ideal bear habitat and dernity of bears is considered
low, bear proof garbage containers should be required. Carelessly handled trash auracts wildlife problems.
Those species of wildlife generally considered least desirable when near housing (bears, skunlc, coyotes and
racoors) are atrracted o trash. Popul:rtion densities of these species usually increase when humens do a poor
job of trash management.
Third, ttre los Amigo Rarrch Plan sures that any fences built will be less than 42 irrches tall and will nOf
define a property boundary but only used o fence a building envelope. To facilitate the flow of dl wildlife
through this properry, we recommerd rhil serreral lots have building ewelopes defined before approval. Thesc
building envelopes should avoid crossing draws deer and elk may use to reach severe winter range. We
recommend thar los on opposite sides of a draw have building envelopes that leave as much of the draw open
as possible. Predefined building envelops are recommended for the following loa:
-l'?-
DEPARTMENT Of NATUR L RESOURCES. Jamcr lochhcrd, Excsrtivc Dirccror
WILDLIFE COMMISSION, Arnol<i Salazar, Chrirrnen . Rcbccce Fnnt, Vicc Chrinrun r Mrrt LrVrllcy, Sccrarry
Rcv. Jcssc l-. tloyrt. Jr., Mcmbcr o Jamcs R. [,ong, Mcmbcr o Chrrlcr D. Lc*,ir, Mcrnbcr o John Stulp, Mcmbcr o louir Swill, Mcmbcr
January 5, 1998
Page2
Filing 6 - Lots 5, 6,7 ,9, 33 and 37.
Fihng 7 - Lots 34,36,38, 40, 42,43, M,47 and 48.
Filing 8 - I-ots 9, 10, 11, 16, and 17.
Filing 9 - Lots 2,4,6,42,4 and 46.
Thank you for the oppommity to coulment.
Sincerely,*rys( Yl,*
Larry L.Ereen
District Wildlife Manager
4a --
a
STATE OF COLORADO
Roy Romer, Governor
DEPARTMENT OF NATT]RAL RESOURCES
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ForW/ildW_
For People
Thank you for the opportunity to comment.
Singgrely, - ,1-1
5/6tt-r1 (>a "4*ui*1,-
Larry L. @reen
District lVlO ife Manager - lq'
DEPARTMENT OF NATURAL RESOURCFJ, James Lochhead, Executive Director
WILDLIFE COMMISSION, Arnold Salazar, Chairman o Rebecca Frank, Vice Chairman o Mark LeValley, Secretary
Bernard L. Black, Member . James R. Long, Member r Charles D. Lewis, Member o Louis Swifl, Member
DIVISION OF WILDLIFE
AN EQUAL OPPORTUNITY EMPLOYER
John Mumma, Director
6060 Broadway
Denver, Colorado 80216
Telephone: (303) 297 -1192
50633Highway6&24
Glenwood Springs, CO 81601
303-945-7228
March 11, 1998
Mark Bean
Garfield County Planning Department
109 8th Street, Suite 303
Glenwood Springs, CO 81601
RE: Comments on Los Amigos Ranch, Filings 5A-11
Dear Mark,
Since my letter dated January 5, [998, I have had a chance to discuss my recommendations with Greg
Boecker. After reviewing a beuer map of the area, I have altered some of my recommendations. This letter
is a follow-up attempt to clarit/ some misunderstandings.
Greg Boecker was concerned about what was meant by bear proof garbage containers. Certain
companies build garbage containers with heavy dury lids and openings that look like a mailbox letter drop,
however, other designs of containers that preclude bear entry are acceptable. Garages or small sheds with
doors and windows closed are usually bear proof. If any trash is to be stored outside of an enclosed building,
other than on the same day it is set out on the curb for pickup, bear proof containers should be required.
I recommended that several lots have predefined building envelopes to preclude fencing of areas near
draws that deer and elk would use to move to critical winter range. After reviewing a better map, I have
dropped several of these lots from this list. However, there is still some confusion. Los Amigos covenants
allow fences of less than forty-two inches to fence a building envelope but not a property boundary. For this
reason, if no building enveiope is required, a landowner may construe his building envelope to include all but
a few feet from the property boundary'. Due to the wording of Los Amigos covenants, I would still like to
recommend predefined building envelopes on the following lots:
Filing6-Irts6and7.
Filing 7 - Lots 34, 36, 38, 40,42,43,47 and 48.
Filing 8 - Lots 9, 10 and 11.
Filing 9 - Lots 2, 4 and 6.
Garbondale & Hural Fire protection District
-
300 Meado rood Drive
o 81623
9e2491
963{569
February 18, 1998
Mark Bean
Garfield County Planner
109 Eighth Street, Suite 303
Glenwood Springs, CO 81601
RE: Los Amigos Ranch Preliminary Plan, Fiting 6 Through Filing 10
Mark:
I have reviewed the prelimrnary plan application for Los Amigos Ranch. There is very little change
rn the plan from the previous submittal from a fire protection standpoint. I would offer the following
comments.
Annexation
I met with Greg Boecker to discuss annexation into the fire district. We have recommended that the
developer petition the Glenwood Springs Rural Fire Protection District (GSMPD) for exclusion of
thetr area that is currently within the development. The area excluded by the GSRFPD along with
the areas outside either district could then be ncluded into the Carbondale & Rural Fire Protection
District. Thrs should take place before the recording of finalplats.
Water Svstem
I have met with Greg Boecker to review fue hydrant locations and spacing. We have agreed on a
design that is appropriate for the development based upon the lot locations and densrty.
Please call if you have any questions.
BillGavette
Fire lvlarshal
cc: Greg Boecker
40-
Gilfi€LO MUNTY
I ('*
Carlrondale & Hural Fire Protection Distrlot
300 Meadoryood Drive
Carbondale, CO 81623
(970) s6S2491
Fax (970) 963{569
January 5, 1998
Mark Bean
Garfield County Planner
109 Eighth Street, Suite 303
Glenwood Springs, CO 81601
RE: Los Amigos Ranch Preliminary PIan, Filings 5A-11
I have reviewed the preliminary plan application and have recently visited the site with Vince Urbina
of the Colorado State Forest Service and Greg Boecker. I would offer the following comments.
Fire Protection Jurisdiction llhe northern portion of filing 6 and the northern half of filing 7
currently fall outside the boundaries the Carbondale & Rural Fire Protection District and are not
within any fire protection district. I have discussed this with Crreg Boecker and have recommended
that these areas be anne><ed into the fire distnct prior through the petition process prior to final plat.
Ftling 8 with the exception of lots 2,3 and 4 and all of filing 9 appear to be withrn the boundaries of
the Glenwood Springs Fire Protection District. Two likely scenarios exist for providing service to
these areas. One would be for the Carbondale & Rural Fire Distnct to provide service through an
agreement with the Glenwood Spnngs Fire Protection District. The other would require the transfer
of legal jurisdiaion between the two districts ttnough an exchrsion/inclusion process. Representatives
of the two districts are scheduled to meet and discuss this issue.
Access The road layout is essentially unchange from the sketch plan. Access ttuoughout the
subdivision appears to be adequate.
Water Supplies The proposed water system generally appears to be adequate for the development.I would recommend that the fire hy&ant spacing be reduced to 500 feet in accordance with
APPENDIX III-B of the Uniform Fire Code.
Impact Fees The development is subject to impact fees adopted by the District. Fees are subject
to penodic rwiew by the distria. F'ees are based upon the per lot impact fee adopted by the District
at the time of recording of final plat or at the time of execution of an agreement between the
developer and the district.
Please call if you have any questions.
BYIM
Bill Gavette
Fire Marshal
![lr8-r iggs
cc: Greg Boecker €l-
United States Department of the Interior
BUREAU OF LAND MANAGEMENT
Glenwood Springs Resource Area
50629 Highway 6 and}4
P.O. Box 1009
Glenwood Springs, Colorado 81602
January 5, 1998
Mr. Mark Bean
Garfield Counry Planning Department
109 8th Street - Suite 303
Glenwood Springs, Colorado 81601
Dear Mr. Bean:
In response to your request for comments regarding the proposed Los Amigos Ranch, Filing 5A-ll project, I
offer the following statements for your scheduled January 14, 1998 planning commission review.
I am attaching copies of previous correspondence pertaining to the Los Amigos Ranch PUD. Although it
appears that these filings do not abut public lands, we would still anticipate that a development of this magnitude
will create detrimental impacts. Of specific concern to the BLM is the potential for increases in OHV use on
adjacent public lands and the loss of big game winter range on private lands.
The loss of habitat will force more animals onto the remaining public lands in the area, resulting in a decline in
habitat condition until the big game populations are reduced to where they are in balance with the available
habitat. Again, we would like to point out the necessity of providing migratory corridors for big game animals
allowing movement between open space areas and other public and undeveloped private lands.
Under Colorado statutes, it is a landowner's responsibility to construct, and maintain in good condition, a lawful
fence protecting their property in order to recover any damages from trespass livestock.
We would also recommend for larger scale projects such as this one, that the developers/contractors be requircd
to provide locations on-site for temporary camping facilitres for those construction workers having no permanent
residence. We would also encourage the developers and contractors to consider providing some temporary
quarters on-site or at commercial facilities as a component of their compensation package for some of their
seasonal employees. We feel this is a reasonable mitigation measure that would reduce crowding, trash,
saniution and enfcrcement prcblems in public campgrounds anil olr dispersed camping areas on other public
lands.
Thank you for the opportunity to comment. If there are any questions, please contact Leonard Coleman of this
office at 947-2814.
Sincerely,
-fr*,oi7jlml
IN REPLY REFER TO:
7//L/.d-,1 7//./'4
Michael S. Mottice
Area Manager
Attachements
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Cr'LL*-LuM:*l
A. Vince Urbina
Assistant District Forester
CC:Bill Gavette - Carbondale FPD
Guy Meyer - Garfield County Sheriff's Office
Greg Boecker
| ,---J- State Services Buildin$
E^T#t--o*.^ttt.*,1'r',i;XT.:ffiIlTfr$iJanuary 29, 1 998
Mark Bean
Garfield County Planning Department
Teleohone: (970) 248-7325€
109 8th Street, Suite 303
Glenwood Springs, CO 81601
Re; Los Amigos Ranch, Filing 6-10 Wildfire Hazard Review
Mark,
I received this new preliminary plan from your office on January 28th. Because it
appeared to be very similar to the original application that I reviewed, I called your
office to find out what had changed from the previous application. Stella informed me
that there had been some water problems and that the overall development had been
downsized. After our discussion I could see there was no need to change my
comments addressed in the original letter of December 13, 1997. Therefore, I stand
by my recommendations of that first letter dated December 31, 1997. This
application did reference Exhibit E6 as having more information on wildfire issues.
exhibit was not included in either of my documents. I would like to have if for my
if that is possible.
Please feel free to call me with any questions.
Sincerely,
This
files
* 23-
;;gp 3 t 1990
December 31, 1997
Mark Bean
Garfield County Planning Department
109 8th Street, Suite 303
Glenwood Springs, CO 81601
Re: Los Amigos Ranch, Filing 5A-11 Wildfire Hazard Review
222 S. 6th Street Room 416
Grand Junction. Colorado 81501
Telephone: (970) 248-7325
Mark,
I read through the applicaticn anC visited the srtc w'ith Grog Boecker and Bill Gavette of
the Carbondale Fire Department. As you know, it is a large development so I will limit
my comments to generalities rather than specific lot recommendations. Access to the
property is from County Road 114. The road into the older filings is a two-lane paved
surface with drainage ditches on either side of the road that are mostly devoid of
woody vegetation. lwas told that these roads meet the existing county standard. ln
the plan there are drawings of the proposed typical roads for the development. Los
Amigos Drive, which services the majority of all filings, currently meets the National
Fire Protection Association (NFPA) 299 standard for the Protection of Life and Property
from Wildfire. The 299 standard calls tor 12 foot lanes with 4 foot shoulders for a
total traveled way of 32 foot. The fact that the drainage ditches are cleared of woody
vegetation adds to the overall effectiveness of Los Amigos Drive as a fuel break and
an escape route for local residents. lt would be a good idea to keep the woody
vegetation out of these drainage swales.
The cul-de-sacs are shown as coming on to Los Amigos Drive at a right angle. This is
desirable for visibility and access. The 299 standard recommends a 5O foot radius for
cul-de-sacs. The plans show a 45 foot cul-de-sac radius but it looks like there will also
be a shoulder which doesn't appear to be counted in the overall measurement. The
Carbondale Fire Department should have the final word on the proposed cul-de-sac
diameters. The road drawing for the Rural Residential lots (r.e., Filing 8) does not show
much detail. I recommend incorporating a turn around at the end of this access road
for emergency service vehicles.
We drove through the development on an existing farm road and several historical
ranch roads. The main road and cul-de-sacs were staked and mowed to see where
they will be put situated. ldon't foresee any problems with steep grades. Greg did
show us several existing and proposed "fire lanes". These all help with egress in the
event of a catastrophic fire. All in all, the road system looks good.
GAifiELo couNry state services Building
44-
ilsl 0,9.19F8
LOS AMIGOS - PAGE 2
A high percentage of the lots are situated along the southwest edge of a bench above
Highway 82. This bench is not visible from the highway. The slopes leading up to this
bench are steep and support primarily pinyon/juniper trees with little to no vegetation
(i.e., grass, forbes and shrubs) in the under story. These pinyon/juniper stands would
be rated as a severe wildfire hazard by Colorado State Forest Service (CSFS) standards
because of the slope steepness and density of the conifers. For this reason, I
recommend that all structures be situated a minimum of 50 feet from the ridge line
(see enclosed NFPA 299 Figure 3-2.4b1. Greg had already intended to require this
stipulation before I mentioned anything about the potential problem, because he
understands the potentially dangerous situation.
The existing vegetation on these lots can be grass, sage and pinyonijuniper in various
combinations. Most grassy lots would be rated as a low wildfire hazard. Sage/grass
lots can be a low to medium hazard. Lots that are better than half conifer would be a
severe wildfire hazard. Even though there are some lots rated as severe, the fact that
these lots are not on steep slopes and we are dealing with pinyon/juniper vegetation
leads me to believe that the wildfire hazard can be readily mitigated by incorporating
defensible space principles. My wildfire mitigation recommendations are as follows.
1) For a distance of 10 feet around all structures establish and maintain vegetation at
6 inches or less (i.e., mowed lawn). No woody vegetation should be allowed to remain
within this perimeter, either from existing stands or proposed landscaping. ln addition,
flammable materials should not be stored in this zone.
2) For a minimum distance of 30 feet around all structures thin existing trees so that
the edges of tree crowns are no closer than 10 feet at maturity. As the slope
percentage increases the minimum defensible space distance will increase (see
enclosed chart). For example, homes on 1O%o slopes should have a minimum
defensible space distance of 35 feet uphill and to the sides, and 37 feet downhill.
Homes on 2Oo/o slopes need a minimum of 40 feet uphill and to the sides, and 47 feet
downhill. ln addition, the lower branches should be pruned off to eliminate ladder fuels
which can allow a fire to burn from ground level to lower tree branches. These
branches should be removed up to half the total height or 10 f eet whichever is least.
When removing trees as part of the defensible space process, try to leave a mix of
young and old trees (i.e., unevenaged stand). An unevenaged forest is healthier than
an evenaged forest.
3/ All dead wood within 100 f eet of structures should be removed.
Greg mentioned that non-combustible roofing material would be required. That's a
good idea. Feel free to call me with any questions about my comments.
Sincglely,
Ct 1.--r^- l/)-Gl-,.*
A. Vince Urbina
Assistant District Forester
Bill Gavette - Carbondale FD
Guy Meyer - Garfield County Sheriff's Office
Greg Boecker
cc:
, zu-
Wright Water Engineers, lnc.
8lB ColoradoAve.
P.O. Box 219
Glenwood Springs. Colorado 81602
19701 945-7755 TEL
19701 945-9210 FAx
(303) 893-l 608 DENVER DTRECT UNE January 9, 1998
Mark Bean
Garfield County Planning Office
Regulatory Office & Personnel
109 Eighth Street, Suite 303
Glenwood Springs, Colorado 81601-3303
RE: Los Amigos Ranch - Preliminary Plat Review
Dear Mark:
At the request of Garfield Counfy, Wright Water Engineers, Inc. (W'WE) has reviewed the
preliminary plat submittal for Los Amigos Ranch Filings 5,A. through 11 dated November 26,
1997 prepared by Schmueser Gordon Meyer. In addition, we reviewed the Preliminary Plan
Application notebook dated November 20,1997. The following presents are corrments on water
supply, wastewater, drainage, roads, geological hazards, and miscellaneous design details.
SUMMARY
From a technical standpoint, the preliminary plan submittal is generally in conformance with
County regulations and standard of practice for engineering design. However, there are a few
major concerns such as adequacy of the proposed sewage disposal system and several minor
items that should be resolved, addressed, and/or revised as appropriate prior to approval or as
part of an approval of the subminal.
WATER ST]PPLY
The quantity calculations for in-house water supply is based on 80 gallons per day
per person and 3.5 people per single-family residence. For planning purposes, 100
gallons per person per day is rypically used. In addition, larger homes which
include guest residences or "in-law" residences will often house up to 5 or 5.5
people per day. Acrual water usage could be more than what was estimated.
The preliminary plan application report states that the water supply will be
chlorinated and a 30-minute conact time will be achieved through 460 feet of a,24-
inch line. This 3O-minure contact time will be met as long as the total flow from the
chlorination building is less than 370 gallons per minute.
DENJVE,R ti0Jl ,r80,r i 00 aJRA IGO t970t 259-741t-26'EOULDER - (3031 473.9500
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 2
o Well No. 6 should be located and shown on the Master Water Plan Sheet.
o We recommend the water line minimum depth of cover be at least six feet, and
preferably seven feet, rather than the 5.5 feet proposed.
o The minimum operating pressure on the design analysis for the water system is 20
psi. This is low for a single-family residence and will require booster pumps for
individual lots.
o The water system analysis includes water service for the four rural lots; however,
service line connections to these lots, especially to Lots 2,3, and 4 would either
require a separate easement through the adjacent single-family lots or a very long
service line. We recommend easements be added to adjacent lots that would
accommodate the shortest route for water service lines to serve these four rural lots.
The storage tank sizing appears to be adequate for the proposed population.
We understand that the Carbondale & Rural Fire Protection District will be
reviewing the drawings and the hydraulic computations for fire flow requirements,
hydrant spacing, cul-de-sac lengths, and the hydrant detail. In some cases, the
hydrant spacing appears to be in excess of the proposed 800-foot spacing that is
discussed in the report.
WASTEWATER
The rypical trench section shows the depth of cover to be 5.5 feet. This will
probably be acceptable for sewer lines with steep slopes. The profiles on Sheets S1
through 54, however, show areas where cover is less than 5.5 feet and should be
adjusted to maintain the minimum cover.
Twenty-one exploratory test pits were excavated to evaluate the subsurface
conditions. [n many of the exploratory pits, practical refusal was encountered at less
than six feet due to a hard, dense rock formation. Percolation tests were performed
adjacent to some of the pits and percolation rates were within acceptable ranges.
However, according to Counry shndards, areas with bedrock less than eight feet
deep require a mound or other engineered system. Based on the rezults and
locations of the tesr pits, this appears to be the case for the majority of the lots. Sirc
specific analyses will determine the rype of system for each lot.
-27-
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 3
Easements should be provided for sewer mains that are outside of the road right-of-
way. For example, Lots 40, 3, and 5 on Drawing 51, Lots 1 and 52 on Drawing
52, and Lot 1 on Drawing 54.
BOCC Resolution No. 96-34 requires central sewer for certain lots and allows ISDS
for the remaining lots subject to the applicant submitting an analysis of
environmental and health impacts for review by the BOCC and the Colorado
Deparunent of Health. We did not find such an analysis in the submittal.
Resolution No. 96-34 also conditions use of ISDS on a favorable recommendation
from the State regarding the proposed method of sewage disposal.
The existing Spring Valley Sanitation District (SVSD) wastewater treaftnent plant has
a permined capacity of 52,000 gpd. Data presented in the submittal show that
existing development sewer demands total 51,840 gpd and there is no existing
capaciry to serve the proposed Filings 5A through 11.
The approved Site Application for the proposed expansion of the SVSD treaunent
facility to serve an additional 110,000 gpd expires February 26, 1998. It is our
understanding that plans and specifications for the expansion have not been submitted
to the State and the approval will likely expire.
o The Site Application approval dated February 26, 1997 required the SVSD, in
accordance with State policy, to develop a service area to include all existing and
funrre development adjacent to existing sewer service (Item 6). It is otu
understanding that this requirement was appealed due to financial hardship. This
provision of the Site Application approval was subsequently removed.
r The SVSD stated in a letter dated November 25, 1997 that the District can and will
serve those portions of the Los Amigos submittal proposed for central sewer.
However, until the District obtains a Discharge to Groundwater Permit (i.e.,
demonstrates that the existing facility is operating in compliance with applicable
standards) and obtains approval for the design plans and specifications and a
Discharge to Groundwater Permit for the proposed expansion (and new site
application if existing approval expires), we do not believe the District can
demonstrate the ability to serve the proposed project.
DRATNAGE
o The drainage calculations reference 18 drainage elements. However, they are not
identified or labeled on any of the drawings.
1g-
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 4
The culvert sizings are all based on inlet control which is acceptable. However, a
maximum headwater to depth ratio should be held at 1.5. This may affect culvert
size. Drainage Elements No. 15 and 18 both appear to be undersized.
The impervious coverage used for the drainage calculations assumes a building
footprint, including driveways and garages, of 3,500 square-feet. Based on existing
development, we believe this should be closer to 5,000 to 7,000 square-feet.
Subdivision Regulation Section 9:43 states that "new developments, where they
create runoff in excess of historic levels, detention ditches and ponds may be
required to retain up to the 100-year stonn. " Existing conditions for this site were
not calculated so there is no analytical comparison as to whether or not there are
downstream impacts from this development. We recommend that this analysis be
conducted to determine if detention is required.
Due to the concentration of flows in areas that may be highly erodible, we
recommend the use of BMPs to minimize the impacts of erosion due to development.
In areas where culverts are proposed under the new roads, we recommend the
following. First, culvert outlets should be protected with riprap. This is especially
important on the steeper culverts. Secondly, we recommend that the discharge be
directed into a drainage easement which will carry flows along the property lines or
into existing swales. In areas where there are no existing swales, the flow should
be re-disbursed so as to minimize the impacts of concentrated flow which could
cause erosion below the property.
The ditch sizing calculations should be revised to reflect the following items. First,
channels with slopes that are steep enough to create critical depth should be sized for
critical depth and not for super-critical depth. Secondly, velociry should be
considered and appropriate channel linings and/or energy dissipation included in the
design.
The Drainage Master Plan Sheet LAD and the Drainage Element Worksheet in the
calculations do not correlate at all locations. For example, the culverts for basins
6, 8, and 10 are not shown. The plan is missing several culverts that are noted in
the calculations and also includes several culverts that are not noted in the
calculations. These should be corrected to match each other and flows and culvert
sizes verified.
-z?-
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 5
o
ROADS
There are several culverts located at low points in the roadway, but are not located
in the swale centerline of the topography immediately adjacent to the road. These
should be re-evaluated to ensure that flows will reach the culvert. Two examples
include a culvert located at Station 47 +L0 on Los Amigos Drive and a culvert
located on West Road at Station 36+90.
The side slopes used to size the roadside ditches are all at2 1. However, this does
not match the typical ditches shown on the road cross sections. This should be
resolved.
There is a worksheet for a circular channel flow in the calculations. However, it is
not clear what this pertains to.
The major swales shown on the drawings should be evaluated for depth of flow
relative to the proposed building sites immediately adjacent to it.
Drainage easements should be added where applicable.
The entire subdivision is served by a single road access off of Counry Road 114.
We recommend adding a second access road.
Road B is shown with a vehicle trips per day of 230 which would put it in the
category of secondary access versus rural access as proposed in the submittal.
The cross-section used for the rural access shows a 2-foot distance between the
shoulder and the center of the flow line of the adjacent ditch. However, county
regulations require 6-foot minimum ditch width which would make this dimension
3 feet.
There are several radii that are less than those noted in the county regulations.
There are several stretches of road that exceed 8 percent grades as noted in the
report. However, we did not see any that were over 10 percent, which is the
maximum allowed in the County Regulations.
There are at least five cul-de-sacs that exceed the 600-foot length and several dead-
ends. This exceeds the County's standards for cul{e-sacs and dead-end streets.
'30-
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 6
There are several intersections off of Los Amigos Road that occur on tight curves.
Sight distances should be addressed.
Access to rural Lot 4 is not defined on the drawings. Responsibility and design
standards for construction of the access to rural Lots 1 ,2, atnrd 3 should be clarified
and defined.
A cost estimate analysis for repair of County Road 114 was prepared by Schmueser
Gordon Meyer in April 1996. The estimate appears to be reasonable for the stated
assumptions. This estimate is for a one-time cost and should, ideally, be done after
construction of improvements are complete. However, with the proposed extended
phasing, intermittent repair work could be needed which is not included in the cost
analysis.
The submittal states that a left-turn lane was constructed at County Road 114 and
Los Amigos Road. As constructed drawings should be submitted for review.
GEOLOGICAL HAZARDS
There are several hazard areas noted in the submitted reports. One is a landslide
area and the others are a series of faults. The report recommends that building sites
not be located near these areas. We recommend the faults and the landslide areas
be shown on the site plan, including any recommended setbacks for proposed
buildings.
The landslide areas (two are noted in the Lincoln-DeVore report) are discussed as
being fairly stable. However, there is a possibility that the proposed culverts will
concentrate surface runoff and affect the drainage in these gullies which could, in
turn, affect the stabiliry. We suggest that this scenario be reviewed by the
geotechnical engineers. The stability of these areas are of concern, especially where
they leave the project site and could potentially effect neighboring properties.
The Lincoln-DeVore report references the palisades topography and recommends that
setbacks be required from any of the palisade formations. This information should
be identified and transferred to a site plan with appropriate setbacks shown.
The soils report, done by Hepworth-Pawlak, identifies a Basalt formation which in
many locations is within 6 feet of the ground surface. This may affect the ability to
install a standard ISDS system.
*3/'
Mark Bean
Garfield County Planning Office
January 9, 1998
Page 7
DETAILS
Revise water/sewer crossing to include crossings with new sewer.
Service line details should show property lines. The water service should include
a marker post.
Recommend bedding under the base of standard manholes.
Hydrant placement note should be revised since there is no curb and gutter on this
project. Also need to label depth of bury (or cover).
Label side slopes and/or width of drainage outlet swale.
I^abel pavement sections (i.e., depths of materials, etc.) of road sections.
Please call if you have any questions or need additional information.
Very truly yours,
WRIGHT WATER ENGINEERS, INC.
PMB/MJE/dIf
921-M7.UO
L vbbJ LrL. uqLLvJ, ,
Senior Water Resources Engineer
Mi
-,rz-
818 ColoradoAve.
P.O. Box 219
Glenwood Spnngs. Colorado 81602
l97ol 945-7755 TEL
(9701 945-9210 FAX
{303) 893-r 608 DENVER DTRECT UNE
March 4, 1998
Mark Bean
Garfield County Planning Office
Regulatory OfFrce & Personnel
109 Eighth Srreet, Suite 303
Glenwood Springs, Colorado 81601-3303
RE: Los Amigos Ranch - plgliminary Plat Review Drainage Submittal
Dear Mark:
At the request of Garfield County, Wright Water Engineers, Inc. flMWE) has reviewed the
revised preliminary plat submittal for Los Amigos Ranch, Filings 6 through 10 dated February
9, 1998. The revised submittal generally differs from the original zubmittal in that it eliminates
the proposed lots that would have been served by the Spring Valley Sanitation District and
responds to the issues raised in review of the original submittal.
SUMMARY
In general, the revised submittal addresses the concerns noted in the our January 9, 1998 letter.
There were, however, several items still unresolved that were discussed 31 n 6ssting with
County staff on February 13, 1998. A meeting was scheduled with the applicant on Febnrary
24, L998 with Dean Gordon and David Kou of Schmueser Gordon Meyer; Greg Boecker,
owner's representative; Michael Erion and Peggy Bailey; and Mark Bean. At this meeting, we
discussed several unresolved iszues which are noted below.
1. The plat still shows lots in the Spring Valley Sanitation District, but includes a note
saying that they are "not developable. " We discussed if this would be acceptable to
the Counry. It was suggested at the meeting that these lots be merged with the
adjacent lots rather than noting them as being undevelopable. This seemed to bc
acceptable to the applicant.
2. There appe:m to be some unresolved issues regarding fire protection jurisdictional
areas. In particular, the applicant mtrst annex a portion of the site into the Carbondale
Rural and Fire Protection District and, secondly, there is an area that is within the
Glenwood Springs Fire Protection Districr. We understand that it is the applicant's
intent to have the entire site within the Carbondale Rural and Fire Protection District
D{JRA,IGO t9701 259.74t \.DENVER 1303t 48G,1 /00
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BOUI-DER - 13031 173-9500
-.-.-.3.-
Mark Bean
Garfield County Planning Office
March 4, L998
Page 2
J.
4.
prior to final plat. At this meet'ng, a letter was zubmitted from the fire deparhent
stating that the road design and hydrant spacing of the project is acceptable to the
Carbondale Rural and Fire Protection District. If Glenwood Springs Fire Protection
District serves a portion of the project, they should also comment on the project.
The effects of development on drainage has still not been completely addressed. The
applicant stated in their resubmittal that post-develop flows will increase but, the
amount is negligible. It was our recommendation that the applicant address the
impacts of these increased flows on off-site conveyance facilities such as channels and
culverts. A follow up submittal was made on February 27 , 1998 addressing drainage
related issues and is discussed later in this report.
We discussed rurai lot 3 in that most of the lot is covered by either landslide area or
fault lines. Our recommendation was to require a building envelope for this lot
because it appears that not much of the lot is available for development. The
applicant, however, feels that it is possible to constnrct a home on the landslide area
based on work that has been performed by their geotechnisnl engineers. Mark Bean
suggested that they include some language about development of this lot requiring a
geotechnical engineer to review and sign off on the location of any proposed
strucn[es.
We discussed access and utilities for rural lots 1 through 3 and made the point that the
access and utiliry corridor for lots 2 and 3 is very long. Dean stated that this is not
a technical iszue and should not be of our concern. However, we believe that wells
are a poor choice for these rural lots given the history of wells in this area and given
the number of ISDS system that will be installed in this area. Therefore, it is our
recommendation that the developer help facilitate the shortest connection possible to
the central water system with easements.
We discussed the requirement of BOCC Resolution No. 96-34 requesting an analysis
of environmental and health impacts which hes not been submitted. In particular, we
were interested in seeing a mass balance analysis tracing the migrarion of nitrates and,
in particular, a discussion should be made regarding the impact these ISDS systems
will have on existing wells adjacent to the project. This has been addressed in a
subsequent zubminal dated March 3, 1998 and is addressed later in this report.
5.
6.
Mark Bean
Garfield County Planning Office
March 4, 1998
Page 3
DRATNAGE
Schmueser Gordon Meyer submitted a letter report dated February 27,1998 addressing drainage
issues related to the development of Los Amigos Ranch. This letter is in response to our
recommendation that an analysi5 be conducted to evaluate the impacs of development otr runoff
at and below the project site. Of particular concern is the downstream drainage facilities,
including open channels and culverts, that may be impacted by increased flows from this
development.
The Schmueser Gordon Meyer letter report proposes the use of on-site detention ponds for
maintaining historic flow rates under developed conditions. The drawing LAD, Drainage Master
Plan, was modified to include six detention ponds located in four drainage [n5ins, n11 vvithin the
property boundaries of Los Amigos. The letter report commits to perfonning drainage
calculations and final design of the detention facilities at the final design.
ln summary, we believe that the proposed concept of on-site detention ponds as shown on the
revised )6inage Master Plan will meet County criteria and will address the particular concerns
of impacts to off-site culverts and channels. County Subdivision Regulations require
computations of expected flows and design of the proposed facilities at preliminary zubmittal.
The letter report did not include any computations. However, the concept appears reasonable
and can likely be imptemented as shown with relatively few modifications at the final submittal.
The responsibilities for maintenance of the ponds need to be specified.
In reviewing this zubminal, WWE performed a field inspection of the facilities downstream of
the noted design points and the Los Amigos properry. Our field investigation is summarized as
follows:
1. Drainage Basin 2 is the largest basin and appears to contain much of the Los
Amigos properry. Runoff drairs off of Los Amigos property through an open
channel and into a 60-inch CMP under Highway 82. The open channel betrveen
the Los Amigos properry and the culvert is approximately 1,500 feet long. It is a
poorly defined channel with a scattering of large boulders characteristic of a debris
flow fan. There are several homes on this debris fan. The 60-inch culvert
includes a headwall and is clean with no sediment or trash in the pipe. WWE
believes that the most serious concern about drainage Basin 2 is the potential
impacts on this debris flow fan. Schmueser Gordon Meyer is proposing two
derention ponds in this basin ro mainuin historic flow rates under developed
conditions. These ponds are locared above the steep canyon area and on the flaner
portions of the project site.
-35-
Mark Bean
Garfield County Planning Office
March 4, 1998
Page 4
Drainage Basin 3 drains to a 24-inch culvert that crosses under County Road 114.
This culvert is in very poor condition with the end sections having been severely
damaged. In addition, this culvert discharges down below County Road 114 to an
area that is currently under construction and shows no sign of an existing or new
drainage ditch to convey flows away from this 24-inch culvert. This culvert has
no direct impact to the Los Amigos development. However, it is important that
existing flows be maintained under developed conditions due to the downstream
conditions.
Drainage Basin 4 is tributary to an lS-inch diameter CMP also draining under
County Road 114. We were unable to locate the inlet to this pipe, but the outlet
is visible from the road. Flows exit the culvert and drop at least 5 to 10 feet
before hining the ground and flow through a man-made ditch which traverses
through a hayfield. It is unlikely that development or increased flows from the
development will have any negative impact on drainage in this area. However, due
to the potential erosion from the "drop" outlet at the l8-inch culvert, we
recommend they implement the design of the detention pond as shown.
Basin 1 drains through aZ4-nchCMP under the frontage road parallel to Highway
82. This culvert also drains a poorly defined channel with evidence of debris
flows. We recommend that they proceed with design of the detention pond as
shown.
We recommend that Los Amigos proceed with the flrnal design of their proposed detention
facilities as shown on the revised Drainage Master Plan. The Drainage Master Plan shows
several ponds in the upper reaches of the drainage basins. The final design should include a
check to see that there is sufficient drainage area flowing to these ponds to create enough
detention volume that is needed for maintaining historic flow rates. There are also several
detention basins shown within private lots. Therefore, final design should include the
appropriate easements for detention, access, and maintenance.
ISDS IIEALTH AND EI{YTRONMENT ANALYSIS
We received a lener report to Greg Boecker from Resource Engineering dated March 3, 1998
regarding ISDS impacts. This report is in response to the requirement in the BOCC Resolution
No. 96-34 Condition of Approval No. 5(A).
2.
3.
4.
-36'
Mark Bean
Garfield County Planning Office
March 4, 1998
Page 5
The Resourcg Fngineering report indicates that there is no impact to the Spring Valley aquifer
and it is highly unlikely that the Los Amigos ISDS systems will contaminate the groundwater
and wells in the Roaring Fork Valley. This analysis is based on available data and reasonable
engineering assumptions. However, if actual conditions vary significantly from the aszumptions,
the potentii[ impacts may be more or lsss than identified in the analy5i5. In addition, the
cumulative impact of groundwater with a nitrate level of 4 mgll diiuted in the Roaring Fork
valley groundwater may be significant if the existing nitrate concentrations are high. Therefore,
we recommend that the applicant develop a baseline and long-tenn water quality monitoring plan
prior to final plat. The plan should include a threshold limit or trigger at which mitigation of
potential impacts would be reErired.
If you have any questions or wish to discuss this in detail, please feel free to call.
Very truly yours,
WRIGHT WATER ENGINEERS, INC.
PMB/MJE/dIf
v2L47.W
Senior Water Resources Engineer
Michael
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FROM: Wright Water Engineers, Inc-
Egy M.Bailey and Michael Erion
DATE: April 9, 1998
RE: L,os Amigos pisliminary Plan Review
We are in receipt of additional drainage analysis and ISDS analysis for rhe proposed hs Amigos
project. We reviewed the following docurnerus.
r I-os Amigos Ranch plsliminary Plan, Filings 6 through 10, Stormwater Detenti-o!
Analysis, April 1998, prepared by SGM.
o Memorandum rc WWE dated April 8, 1998 from Dave Kotz, P.E. with SGM.
o [-os Amigos Ranch P-U.D. Individuat Wastewater Treatment Systems Groundwarer
lmpact dated April 6, 199t, prepared by Resource Engineering.
o April 8, 1998 letter to WWE from Rcsource Engineering.
o April 9, 199E letter to WwE from Resource Engineerrng.
The following are our comments.
Drainage Analysis
In general, we found the updated drainage analysis including detailed calculations for detention
pond sizing and operation to be acceptable for preliminary plan submittal. The applican: is
proposing the use of four detention ponds located in the upper reaches of the four suFareas
within the site. Volumes have been calculated for maintaining historic ruuoff, under developed
conditiors, for storms up to and including the 100-year flood eveDt. Calculadons indicare that
all post-development flows will tre at or less than existing conditions.
The detention ponds that were zubmitted were a generic computer geuerated pond configuradon
developed to fir in all four basins. Although the calculatioru indicate that this pond will work
in each basin, the final plans 56611 include a detailed grading plan with stage-storage volume
P. 001TEL:9709459210
MEMORANDUM
To: Mark Bean, Garfield County Planning offlrce DR4 F7
-38'
.J\
..AI'RJ :09' 98 (THU)l3:21 IIRIGHT IYATER GLN1I00D TEL:9709459210
MEMO TO: Mark Bean
April 9, 1998
Page 2
relationships developed based on the acrual topography. We reviewed this with Dave Kotz with
SGM and he is in agreement with our comment-
We believe the data submitted fulfills Condition No.
Recommendation.
P, 002
q *rhe planning Commission
ISDS Impact Analysis
The Resource Engineering report concludes rhat their analysis, together with the commitment
to construct and maintain quality ISDS systems with desigu standards and management plan,
indicates that there will be no adverse impacr to groundwater quality. Based on our review, we
generally concur with the Resource Engineering conclusions. The analysis includes a number
of engineering assunptions and judgment. We reviewed the analysis making more conservative
assumptions in all cases and found that the Resource Engineering analysis would result iu a
cumulative total nitrate concentration of ls5s rhan 7 mg/|. This is less than the Sate and EPA
standard of 10 mg/l.
Given the applicability of watcr quality standards and pollutana rypically associarcd with septic
tank/Ieachfield effluent, the primary pollutant of regulatory concern expecred ro be associated
with septic tank/leachfield effluent is nitrate, Niuate is rypically selected as ttre limiting
pollutqnt from the regulatory perspective for several reasons including: (l) pollutants associated
with septic tanlc/leactrfield conamination are commonly known to be nirate and viral/bacterial
contaminants; (2) niuate is hown to be highly mobile in subsurface envirorunents, while
viral/bacterial conraminants are more easily absorbed onto soils; (3) the regulatory limit for
nitrate is low relative to typical nitrate loadings in septic system effluent; and (4) nitrate
coucenrations are quire low in undeveloped and uncontaminated sream sysrems.
We believe this recent detailed analysis fulfills the submittal requirements of BOCC Resolution
No. 96-34, Paragraph 5.
WWE previously recommended a monitoring and mitigation plan in the absence of a deuiled
quantitative aralysis. With this additional analysis, rhe striugent design standards, and the
maintenance plan, we believlthe appLicant has developed an acceptsble dternative approach as
outlined in Condition No- U of the Planning Commission Recommendation-
WWE will have additional deuiled coElments on the design stand.ards and mainrenance plan.
PMB/MJE/dIf
92L-M7.W
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Wright Water Engineers, lnc.
B 1B Colorado Ave.
P.O. Box 2l9
Glenwood Springs, Colorado 81602
1970) 945-7755 IEL
19701 945-9210 FM
1303) 893,i608 DENVER DIRECT LINE
Aprll27, 1998
Mark Bean
Garfield County Planning Office
Regulatory Office & Personnel
109 Eighth Street, Suite 303
Glenwood Springs, Colorado 81601-3303
RE: Los Amigos Ranch Preliminary Plan - Review of Additional ISDS Analyses
Dear Mark:
On April 13, 1998, Wright Water Engineers, Inc. (WWE) submitted our recommendations to
Garfield County regarding ISDS issues for the Los Amigos Ranch Preliminary Plan. Since then,
the County has received additional information from consultants for the adjacent property
owners. This letter presents our review of the additional comments and analyses regarding the
ISDS issues. In addition, as technical advisors to the Board, we have provided a summary of
our opinions on this matter. New information reviewed since our April 13, 1998 letter includes:
o Los Amigos Ranch P.U.D. Potential Impacts on Groundwater Flow and Quality Due
to use of Individual Septic Systems for Domestic Wastewater Treatment and
Disposal, prepared by Mclaughlin Water Engineers, Inc., dated April 1998.
o Testimony by John M. Kaufman, P.G., C.P.G., of Mclaughlin Water Engineers,
Ltd., and John Currier, P.E., of Resource Engineering, Inc. at the April 13, 1998
Board of County Commissioners Public Hearing.
o Memorandum from Garfield County engineer Robert Szrot dated April 17, 1998.
o Addendum to the above-referenced Mclaughlin Water Engineers report received via
fax on Aprrl24, 1998.
o Irtter from Gamba and Associates to Colorado Mountain College dated April 21,
1998 and received with cover letter from Beattie & Chadwick to the Board dated
Aprll27, 1998.
o [,etter report from Resource Engineering to Greg Boecker dated April 23, 1998.
40-
DENVER (303) 480 r 700 DUMN(:O 1970) 259-7411 BOULDER - 1303) 473-9s00
Mark Bean
Garfield County Planning Office
April 27, 1998
Page 2
l*tter from Bishop-Brogden Associates to Greg Boecker dated 4pri123,1998.
Letter from Bruce Collins to Greg Boecker dated April27, 1998.
In addition, it is anticipated that further written comments will be provided by the applicant.
However, we do not believe any of these rebuttal comments or additional analyses will change
WWE's comments presented below.
SLTMMARY
Based on review of analyses by Resource Engineering, Mclaughlin Water Engineers, Gamba
& Associates, Bishop-Brogden Associates, and Bruce Collins, we offer the following comments.
Based on available data and current regulations, properly designed and installed
ISDS systems (conventional, mounded, or other engineered system) appear feasible
for the project.
o Impacts to groundwater quality will result from the use of ISDS systems and can be
generally quantified in terms of change in the concentration of nitrate in the
groundwater. Based on the engineering analyses by Resource Engineering and
Mclaughlin Water Engineers, and other available data, we believe the cumulative
concentration of constituents in the local groundwater will be less than State and
EPA drinking water standards.
Recommendations on Design Standards and Management Plan in WWE's April 13,
1998 letter should be followed. In addition, we recommend that the applicant
develop the detailed design criteria for each type of possible ISDS system to
minimize water quality impacts.
In further response to Commissioner Martin's question on "Engineering Technical
Preference of ISDS vs. Central Sewer, " we believe that, from a water quality
perspective, central sewer is preferable. This is primarily due to the state's ability
to control and regulate a point source discharge to meet both existing and future
standards. Site specific conditions which relate to technical feasibility and economics
of connecting to the nearest central system must also be considered in evaluating the
method of sewage disposal.
4/-
Mark Bean
Garfield County Planning Office
April27, 1998
Page 3
Section 32-l-1006 of the Colorado Revised Statutes 1996 Cumulative Supplement
states that proposed development within a sanitation district's boundary and within
400 feet of an existing central sewer main can be required to connect to the central
system. It is our understanding that the proposed project is outside the current
Spring Valley Sanitation District boundary, but within the district service area. We
recommend that the applicant document, for the record, the technical feasibility and
economic constraints to central sewer including the option presented by the County
Engineer in his April 17, 1998 memorandum. This may be useful to the Board in
their decision process.
Please call if you have any questions or need additional information.
Very truly yours,
WRIGHT WATER ENGINEERS, INC.
MJE/dIf
921-047.040
Michael J. Erion,
4z-