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SPRING GULCH NORTH PARKING LOT
Garfield County
Grading Permit
Application
July 2023
Spring Gulch North Parking Lot I Grading Permit
Application
lntrod uction
The Mount Sopris Nordic Council (MSNC) and the North Thompson
Cattlemen's Association is seeking a Grading Permit in order to
provide access to a proposed parking lot at a new trailhead along
Marion Cemetery Road. The proposed parking lot, which is
situated at a higher elevation and in a more sheltered location than
the existing Spring Gulch Trail System parking, is intended to limit
the climate related loss of skiable days.
Grading Permit Submittal Requirements
o Complete Application: The complete application is included
in the appendix of exhibits.
o Vicinity Map: The vicinity map is included in the appendix
of exhibits, as well as a map illustrating the Spring Gulch
trail system and the proposed parking lot.
r Site Plan: The Site Plan is included in the Grading and
Revegetation Plan Set, which can be found in the appendix
of exhibits.
o Erosion Control Plan and Details: The Erosion Control Plan
and Details are included in the Grading and Revegetation
Plan Set, which cán be found in the appendix of exhibits.
o Reveg€tation and Reclamation Plan:
o Section I - Soil Handling: Please see notes on the
Landscape Plan in the Grading and Revegetation
Plan Set in the appendix of exhibits.
o Section 2 - Weed Management Plan: The team is
requesting a waiver from creating a site-specific
weed inventory along with a site plan showing the
County listed noxious weeds. The site is agricultural
land for cattle grazing. The disturbance to the
I,O62.35-acre parcel is limited to the extents of the
parking lot, which is approximately L acre (or O.09%
of the entire property).
o Section 3 - Site Revegetation and Restoration: The
Landscape Plan and plant schedule can be found in
the Grading and Revegetation Plan Set, see exhibit
4 in the appendix.
Project Team
TrailSvstem Manager:
Mount Sopris Nordic Council
Matthew Annabel
Board Member
PO Box246
Carbondale, CO 8L623
E: matt@back40stories.com
P:97O.4O4.5531,
Propertv Owner:
North Thompson
Cattlemen's Association
William E. L. Fales
President of the Board
4239 Highway 133
Carbondale, CO 81623
E: wmfales@aol.com
P:970.618.1325
Landscape Architect:
DHM Design
Jennifer DiCuollo
Principal I PLA
225 Main Street, Suite 201
Carbondale, CO 81.623
E:
jdicuollo@dhmdesign.com
P:970.963.6520
Spring Gulch North Parking Lot I Grading Permit Application
o Section 4 - Cost Estimate: The team is requesting a waiver
from providing a cost estimate. The work will be
completed with a significant portion of donated time and
resources. The contractor is completing the necessary
work and will work with the Nordic Council on costs-thus
an accurate cost estimate cannot be provided.
Furthermore, the revegetation is limited to seeding the
edges of the parking lot with a proposed pasture seed mix
for agricultural purposes and will not be a large cost.
Financial Security: The team is requesting a waiver from the
financial security submittal requirement. The project is funded by a
non-profit and provides a free asset to the community. As noted in
the Cost Estimate waiver request, the grading and reclamation
work will be completed by the contractor with a significant portion
of donated time. lf requested, Mount Sopris Nordic Council can
provide proof of adequate finances to cover the cost of
revegetation.
Approved State Stormwater Permit: The team is requesting a
waiver from providing a State Stormwater Permit. The project is a
small portion (0.09%) of a large agricultural parceland allwater
will drain onto the property as noted in the Drainage Report, see
exhibit 2 in the appendix.
Soils Report: A soils report is not required as the maximum depth
of cut orfill depth is less than L5 feet and the native slopes are less
than25%.
Drainage Report: The Drainage Report can be found in the
appendix of exhibits.
(Continued)
Appendix of Exhibits
a
a
a
Exhibit 1:
Exhibit 2:
Exhibit 3:
Exhibit 4:
Grading Perm it Application
Vicinity Map
Drainage Report
Grading and Revegetation Plan Set
Civil Ensineerine:
Crystal River Civil
Jay Engstrom
Owner
1101" Village Road UL-46
Carbondale, CO 8L623
E: jay@crysta lrivercivil.com
P:970.404.1144
Contractor
Mike Uncapher
Wester Vegetation
Management
337 Cleveland Place
Carbondale, Colorado,
8L623
E: muncapher@hotmail.com
P:970.618.2567
llPage
Exhibit 1: Grading Permit Application
Exhibit 2: Vicinity Map
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Vicinity Map lSpr¡ng Gulch North Parking Lot
Exhibit 3: Drainage Report
Spring Gulch North Parking Lot
Drainage Report
July 6, 2023
Existing Gonditions
This property being discussed is located in Garfield County outside of Carbondale, Colorado. The
site is designated as Property lD #246110100003 and is described as Section: 10 Township: I
Range: 89 SEC. 3 LOT. This site is located on a large parcel of land that borders ranch land and
undeveloped lots to the north, east and west. BLM land is further north, and Forest Service land
is located to the west, while the southern edge of the property borders additional ranch land. This
project is specifically referencing a small portion of this lot, just South of Marion Cemetery Road.
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Shown above is an image displaying the location of the Spring Gulch TrailSysfeø
The site is currently being utilized by the Spring Gulch Trailsystem, a dispersed trail network used
by the public for Nordic skiing. lt is run by the Mount Sopris Nordic Council in partnership with the
landowners, the North Thompson Cattlemen's Association.
The existing area is undeveloped pastureland, with a gradual slope to the East. The site is
relatively flat and consists of native grasses and vegetation. There are no concentrated flow lines
within the vicinity, and no erosion concerns. No neighboring sites are impacting the historic
d,
Crystal River Civil LLC 970.510.5312 Page 1 of 4
drainage patterns. There are no utilities in the vicinity, and the only development in the areas is
Marion Cemetery Road.
Proposed Conditions
A road base parking lot is proposed on the site, just south of Marion Cemetery Road. This parking
lot will have an upper and lower tier as to reduce grading and disturbance of the site. The lot
consists of 60 parking spaces and will be utilized by Spring Gulch Nordic trail users. Several
existing ski trails will be integrated into the development. This parking lot will be used seasonally
and will be closed and gated during closures. Additional improvements include signage and a
portable toilet. The access has been designed to meet the road and bridge standards, as well as
maintain adequate emergency access. A civil site plan, as well as access plan and profiles, have
been included with this submittal and are to be referenced with this engineering report.
Access
The parking lot has been designed to meet the requirements of the Garfield County Land Use
and Development Code Article 7. The access point at Marion Cemetery Road meets the design
standards of a semi-primitive roadway, and has capacity for 2-way traffic with 8-foot lanes and 2-
foot shoulders. Slopes of the driving surfaces are minimal, and turning requirements for
emergency vehicles are addressed. The 60 parking spaces are deemed adequate for the public
use of the site.
Utilities
No utilities will be provided on the site. A portable waste facility will be located at the lot for use
by the trail users. This will be maintained and managed onsite and will be removed from the site
during the off season.
Drainage Analysis
The drainage design on the site utilizes detention swales, dispersion, and infiltration to provide
adequate mitigation of the developed area. The upper tier of the parking area slopes towards a
drainage basin in between the two parking tiers. This area has been sized to have adequate
storage for stormwater collection and infiltration. The lower tier of the parking area is sloped to
the east and is designed to disperse stormwater into the native vegetation below. These two areas
have been broken into separate basins for analysis, Basin 1 being the runoff from the upper lot
and Basin 2 runoff from the lower lot.
This drainage analysis uses procedures that have been standardized by the Mile High Flood
District's Urban Storm Drainage Criteria Manual, or the USDCM. Peak flows of the site have been
calculated using the Rational Method to determine the impacts the proposed project has on the
existing conditions, along with verifying the capacity of the proposed infrastructure. This method
uses the analyzed basin's area, soil type (assumed soil type C), percentage of imperviousness,
Crystal River Civil LLC 970.510.5312 Page 2 of 4
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time of concentration, and the historic storm data from NOAA Atlas 14 to determine the maximum
flow rate from a specified storm event. The Rational Method uses the equation below to determine
the Maximum Flow Rate:
Q=ClA
Where,
Q is the peak stormwater runoff rate, in cubic feet per second
C is a runoff coefficient of the drainage area
I is the storm intensity, in inches per hour
A is the area of the drainage basin, in acres
The Runoff Coefficient, C, is determined using table 6-5 from the USDCM. To determine the storm
intensity, l, Equation 2.l fromthe City of Aspen's Urban Runoff Management Plan is being utilized,
as it is a neighboring jurisdiction that has more similar historical data in comparison to the
USDCM. For smaller basins with a time of concentration of less than five minutes, a time of
concentration of five minutes is assumed - when smaller times of concentration are used in the
Rational Method, the results tend to be inaccurate, as per the USDCM. The rainfall event used
for this analysis is for a 1-hour 25-year storm event. Below is a table summarizing the calculations
to determine the predeveloped and developed conditions for the onsite basins.
Garfield County requires stormwater runoff from a development to not exceed more than the
historic runoff. For this design, CRC utilizes historic data from a 1-hour 25-year and a 1-hour 100-
year storm event. Detention is proposed to offset the increased flows from new impervious areas
to be released at the historic rate. Basin 1 is proposed to be collected by a detention swale, which
has capacity for full detention of a 1-hour 1OO-year storm event. Below is a table showing the
values determined in the analysis.
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Note: For basins with a flow length of less than 500 feel, a T¡me of Concenfal¡on is assumed at 5 minutes. These calculations arê assuming a NRCS Flydrologic Soil Cìass B.
Ra¡nfalldepth values deriwd from NOAAAtlas 14 data. lnlens¡ty equatìon has been derived frcm the Aspen area NOAAAilas 14 IDF Cutue.
Gondit¡ons
0.00%0.310 5 5.66 1.19295760
6965't9 00 0 0.000/o 0.310 17 3.05 15.112
Condit¡ons
0.480 5 1.7729576.00 8438.40 2A 530/Ò
2.17o/o 0.330 17 3.05 16.08696519.00 15148 00
IFôSIlnámeìt*t ¿n4 (oÃ\(in)fñeì
8438.40 2A 53â/6 '1 36 1 9561Smle29576.00
Crystal River Civil LLC 970.510.5312 Page 3 of 4
Given the rural location of the site, as well as the gradual slopes and large basin below the
development, CRC is proposing to release stormwaterfrom the lower parking lot down the hillside
to the east. This dispersed flow will sheetflow through the native vegetation and will naturally
infiltrate into the soil. This does not impact any neighboring sites and there are no concerns
regarding erosion.
For any information regarding the stormwater design please see the civil grading and drainage
plan. lf there are any comments regarding the stormwater analysis performed for the site, feel
free to contact me directly.
Jay Engstrom
Principal, P.E.
Crystal River Civil LLC
J av@Crvstal RiverCivi l. com
(970) 404 - 1144
Crystal River Civil LLC 970.510.5312 Page 4 of 4
Exhibit 4: Grading and Revegetation
Plan Set (See 24x36 Plots)
æ Newin2022l (MostDifficutt)
æ New in 20221 (Moderate)
Most 0ifficult (two-way)
Moderate (two-way)
Easiest (two-way)
Most Difficutt (one-way)
Moderate (one-way)
Marion Gulch Mutti-Use Trait
Sprinq Gulch Traithead Parking
A NoPubticAccess
LEGEND
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PLEASE NOTE: Spring Gulch is lOO% on private land w¡th public access GENEROUSLY
granted by the North Thompson Cattlemen's Association and Crystal River Ranch.
Public access is for NORDIC SKIING only. Accessing these trails outs¡de of the MSNC
operat¡ng season, OR for any w¡nter use other than nord¡c skiing is TRESPASSING.
There is NO public access between the Spring Gulch Nordic Trail system and the
Marion Gulch trail & parking areas ANY time of year. MSNC is working on permits to
build a new "Upper" Parking Lot along Marion Gulch Rd. in 2023,
Paul's
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Spring Gulch
Parking & Trailhead
WELCOME TO SPRING GULCH!
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Upper Parking Lot
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*NO dogs, motor¡zed equipment, snow or fat bikes,
snowmobiles, sledding, snowshoe¡ng, snowboarding,
tubing, hiking, runn¡ng, etc. allowed. Thank you!
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