HomeMy WebLinkAboutFile Documents.302 Park Ave.0008.2018 (21).ARBKGrading and Drainage Report
Prepared for
Gregg and Dianna Lowe
302 Park Ave, Aspen
P.O. Box 575
Woody Creek, Colorado 81656
970-309-7130
Prepared By
Josh Rice, P.E.
July 2, 2018
November 21, 2017
08/30/2018
Reviewed by Engineering
10/01/2018 2:27:38 PM
"It should be known that this review shall not
relieve the applicant of their responsibility to
comply with the requirements of the City of
Aspen. The review and approval by the City is
offered only to assist the applicant's
understanding of the applicable Engineering
requirements." The issuance of a permit based
on construction documents and other data shall
not prevent the City of Aspen from requiring the
correction of errors in the construction
documents and other data.
i
I hereby affirm that this report and the accompanying plans for the drainage improvements of “Lot 9, 10,
11, and the West ½ Lot 12, Except the North 15 feet Thereof, in Block 2, Riverside Addition” was prepared
by me for the owners thereof in accordance with the provisions of the City of Aspen Urban Runoff Man-
agement Plan and approved variances and exceptions listed herein. I understand that it is the policy of the
City that the City of Aspen does not and will not assume liability for drainage facilities designed by others.
Josh Rice, P.E. License No.
1/11/20187/2/2018
08/30/2018
ii
1. INTRODUCTION ................................................................................................................................. 1
2. GENERAL SITE DESCRIPTION ....................................................................................................... 1
2.1 Existing Condition ..................................................................................................................................... 1
2.2 Proposed Condition ................................................................................................................................... 2
2.2.1 Determination of Major/Minor .................................................................................................................... 2
2.3 Drainage Basins ......................................................................................................................................... 2
2.3.1 Historical Basin EB : 1 ................................................................................................................................... 3
2.3.1 Proposed Basin PB : 1 ................................................................................................................................... 3
2.3.1 Proposed Basin PB : 2 ................................................................................................................................... 3
3. STORMWATER BMPS AND ROUTING ......................................................................................... 4
3.1 General ..................................................................................................................................................... 5
3.1.1 Detention Calculation .................................................................................................................................. 5
3.2 Pipe Calculations ....................................................................................................................................... 6
3.2.1 Pipe A ........................................................................................................................................................... 6
3.2.2 Pipe B ........................................................................................................................................................... 6
3.2.3 Pipe C ........................................................................................................................................................... 6
3.2.4 Pipe D ........................................................................................................................................................... 7
3.3 Inlet Calculations ....................................................................................................................................... 7
3.3.1 Inlet 1 ........................................................................................................................................................... 7
3.3.2 Inlet 2 ........................................................................................................................................................... 7
3.3.3 Inlet 3 ........................................................................................................................................................... 7
3.3.4 Intet 4 ........................................................................................................................................................... 7
3.3.5 Inlet 5 ........................................................................................................................................................... 7
3.3.6 Inlet 6 ........................................................................................................................................................... 8
3.3.7 Inlet 7 ........................................................................................................................................................... 8
3.3.8 Inlet 8 ........................................................................................................................................................... 8
3.4 Trench Drain Calculations .......................................................................................................................... 8
3.4.1 TD:1 .............................................................................................................................................................. 8
3.4.2 TD:2 .............................................................................................................................................................. 8
3.4.3 TD:3 .............................................................................................................................................................. 8
3.4.4 TD:4 .............................................................................................................................................................. 8
3.4.5 TD:5 .............................................................................................................................................................. 9
3.5 Drywell ...................................................................................................................................................... 9
3.6 Operation and Maintenance ..................................................................................................................... 9
APPENDIX A--NRCS SOILS REPORT ................................................................................................. 1
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APPENDIX B--FEMA FIRM MAP ......................................................................................................... 2
APPENDIX C--PLAN SET ....................................................................................................................... 3
APPENDIX D--HYDROLOGIC CALCULATIONS ............................................................................... 4
APPENDIX E--HYDRAULIC CALCULATIONS .................................................................................. 5
APPENDIX F—DETENTION CALCULATIONS ................................................................................. 6
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1. Introduction
This report was prepared to meet the requirements of a City of Aspen Engineering Department Grading and
Drainage Report for a Major Design. The report was prepared for a single-family housing project at 302
Park Ave, Aspen, Colorado, 81611 (the “Site”). Facilities providing water quality capture volume have
been designed in this report and the associated plan.
2. General Site Description
2.1 Existing Condition
The property was platted as “Lot 9, 10, 11, and the West ½ Lot 12, Except the North 15 feet Thereof, in
Block 2, Riverside Addition.” Based on the topographical improvement survey, the lot area is approxi-
mately 6563 square feet.
The Site is located on the east side of aspen, near smuggler mountain (see Figure 1). The soils are described
by the NRCS as, “Uracca, moist-Mergel complex, 6 o 12 percent slopes” (see Appendix A). The hydrologic
soil group is “B.” The lot is currently occupied by a single family home.
Figure 1. 302 Park Ave., Aspen Vicinity Map
(Source: maps.google.com)
The site is located well away from all major drainage ways and is not located within the floodplain bound-
aries the Roaring Fork River. The Site is located within Zone X, as shown and described by FEMA (see
FIRM Map, Appendix B.)
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2.2 Proposed Condition
Existing patio will be removed and replaced. The existing building will be not be changed.
2.2.1 Determination of Major/Minor
The Urban Runoff Management Plan (the “URMP”) has two controlling triggers when determining the
permit requirements: interior demolition and exterior disturbed area. Based on these two triggers, Woody
Creek Engineering (“WCE”) has determined that water quality capture volume (“WQCV”) is required for
the entire property.
The Site is located on a hill with slopes around 4% away from the existing structure. Drainage basins are
delineated on Plan Sheet C.1 (Appendix C, C.1). The basins are described in the following sections. The
drainage issues and WQCV treatment BMPs are also described. Small changes to the topography and
ground cover will be caused by the addition and remodel of the hardscapes. The soil type with not change,
the drainage patter will change in that the flows will be collected, detained, and discharged to the street.
The street is the receiving system: it has been historically and will be in the proposed condition.
2.3 Drainage Basins
Both Historical and proposed basins are described below. Table 1, below, describes the impervious area,
pervious area, total area, percent imperviousness, flow path length, basin slope, runoff coefficients for the
minor (5-yr) and major (100-yr) storm events and runoff flowrates for the minor (5-yr) and major (100-yr)
storm events. Although the Basins are delineated on Plan Sheet C.1 (Appendix C, C.1), they are also
provided in Figure No. 2 and 3, below.
Historical peak flows for the 5-year and 100-year events were evaluated for the Site using a time of con-
centration based on the flow path length and slope. The rational method was utilized for all runoff calcu-
lation.
Table 1. Basin Information
BASIN NO.TOTAL
BASIN AREA
(SF)
IMPERVIOU
S AREA (SF)
TOTAL
BASIN AREA
(ACRES)
IMPERVIOU
S AREA
(ACRES)
%
IMPERVIOU
S
RUNOFF
COEF. 5YR
RUNOFF
COEF.
100YR
FLOW
PATH
LENGTH
(FT)
FLOW
PATH
SLOPE
(FT/FT)
Tc (min)PEAK FLOW
5YR (CFS)
PEAK FLOW
100YR
(CFS)
EB:1 6562.5 0 0.151 0 0%0.08 0.35 63.68 0.079 7.49 0.032 0.2844
BASIN NO.TOTAL
BASIN AREA
(SF)
IMPERVIOU
S AREA (SF)
TOTAL
BASIN AREA
(ACRES)
IMPERVIOU
S AREA
(ACRES)
%
IMPERVIOU
S
RUNOFF
COEF. 5YR
RUNOFF
COEF.
100YR
FLOW
PATH
LENGTH
(FT)
FLOW
PATH
SLOPE
(FT/FT)
Tc (min)PEAK FLOW
5YR (CFS)
PEAK FLOW
100YR
(CFS)
PB:1 3626.7 2059 0.083 0.047 57%0.39 0.55 5 0.5 5 0.107 0.2892
PB:2 2935.8 2935.8 0.067 0.067 100%0.9 0.96 5 0.5 5 0.197 0.4049
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Figure 2. Historical Basins Figure 3. Proposed Basins
2.3.1 Historical Basin EB : 1
Historical Basin EB : 1 encompasses the entire lot with an area of 6562.5 sf. Runoff sheet flows for 63.68
ft with 7.9% slope, resulting in a 100-yr flowrate of 0.284 cfs.
2.3.1 Proposed Basin PB : 1
Proposed Basin PB : 1 is composed of the yard and patio area surrounding the house. The basin has an
area of 3626.7 sf and is 57% impervious. This basin produces 0.289 cfs of runoff, which is captured by
the various inlets on the lot. The slopes and sheet flow distances shown in Table 1 are artificially high
and short in order to force a conservative time of concentration of 5 minutes.
2.3.1 Proposed Basin PB : 2
Proposed Basin PB : 2 is a roof basin. The basin developed a 100-yr flowrate of 0.405 cfs. PB:2 is cap-
tured by gutters and downspouts, which are tied to the pipe network. From the pipe network, runoff is
routed to the drywell. The slopes and sheet flow distances shown in Table 1 are artificially high and short
in order to force a conservative time of concentration of 5 minutes.
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3. Stormwater BMPs and Routing
Low impact design has been utilized where possible to provide WQCV and detention.
9 Principles
1. Consider stormwater quality needs early in the design process.
The architect and owner considered stormwater requirements early in the process.
2. Use the entire site when planning for stormwater quality treatment.
Where possible, overland conveyance was utilized to increase the time stromwater is in contact
with natural systems.
3. Avoid unnecessary impervious areas.
Impervious areas were reduced where acceptable to the owner and the design team.
4. Reduce runoff rates and volumes to more closely match natural conditions.
The proposed peak runoff rates are no greater than historical runoff rates. The historical flow
paths are followed.
5. Integrate stormwater quality management and flood control.
Through the use of onsite BMPs, stormwater quality management and flood control are integrated
in the project.
6. Develop stormwater quality facilities that enhance the site, the community and the environment.
The site, community and the environment are enhanced by reducing the amount of sediment and
other river pollutants conveyed to the stream system. Hopefully, the use of these stormwater
BMPs on this property and throughout the community will improve the water quality of the Roar-
ing Fork River and its tributaries.
7. Use a treatment train approach.
A treatment train approach is not appropriate for this site.
8. Design sustainable facilities that can be safely maintained.
The stormwater BMPs located onsite can be easily and safely maintained and are readily accessi-
ble.
9. Design and maintain facilities with public safely in mind.
Elevation drops to stormwater BMPs are minimal and designed with public safely in mind. A
drywell system is the only feasible system because we are dealing with a relatively flat site, with
an existing structure. Only minor changes to the hardscape are proposed and collection of the
roof runoff is proposed via hardpiping through the 5-ft rear setback. These conditions warrant the
use of a sub-grade system. The available storm system in front of the house allows for discharge
to the City storm sewer system.
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3.1 General
Low impact design has been utilized where possible to provide WQCV and detention. Basin Routing is
described in Table 2, below.
Table 2. Basin Routing
3.1.1 Detention Calculation
To calculate water quality requirements, WCE calculated the total area of the basins, the impervious area
of the basins, and time of concentration of the basins. Overall, the basins total area equals 0.151 acres,
while the impervious area equals 0.115. The time of concentration for existing basins was found to be
7.49 minutes.
Based on an overall imperviousness of 76% percent, the WQCV in watershed inches is 0.16 in (see Ap-
pendix D). In terms of volume, the WQCV over the tributary area of 0.151 acres is 88 cf (0.151 ac X
43560 sf/ac X 0.16 in X 1 ft / 12 in). With a factor of safety of 1.5 applied, the volume is increased to 132
cf. The proposed grading of the site, as well as pipe networks, route runoff into the proposed drywell.
The drywell provides 226 cf of detention which is adequate for the storage required for the 100 year storm
(165 cf). See Section 3.6 for drywell information.
Name Path 1 Path 2 Path 3 Path 4 Final Basin I.D.Treatment
Inlet 1 Pipe A Drywell PB:1 Drywell
Inlet 2 Pipe A Drywell PB:1 Drywell
Inlet 3 Pipe A Drywell PB:1 Drywell
Inlet 4 Pipe A Drywell PB:1 Drywell
Inlet 5 Pipe A Drywell PB:1 Drywell
Inlet 6 Pipe A Drywell PB:1 Drywell
Inlet 7 Pipe A Drywell PB:1 Drywell
Inlet 8 Pipe B Drywell PB:1 Drywell
TD 1 Pipe C Drywell PB:1 Drywell
TD 2 Pipe A Drywell PB:1 Drywell
TD 3 Pipe A Drywell PB:1 Drywell
TD 4 Pipe A Drywell PB:1 Drywell
TD 5 Pipe A Drywell PB:1 Drywell
GU 1 DS 1 Pipe A Drywell PB:1 Drywell
GU 2 DS 2 Pipe B Drywell PB:1 Drywell
GU 3 DS 3 Pipe B Drywell PB:1 Drywell
GU 4 DS 4 Pipe B Drywell PB:1 Drywell
GU 5 DS 5 Pipe A Drywell PB:1 Drywell
GU 6 DS 6 Pipe A Drywell PB:1 Drywell
GU 7 DS 7 Pipe A Drywell PB:1 Drywell
GU 8 DS 8 Pipe B Drywell PB:1 Drywell
GU 9 GU 7 DS 7 Pipe A Drywell PB:1 Drywell
Routing
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3.2 Pipe Calculations
Four pipes will be installed in order to route runoff to the Drywell and then the city storm water system.
Each pipe is described below.
3.2.1 Pipe A
Pipe A captures runoff from Inlets 1-7, as well as Trench Drains (“TD”) 2-5. In addition, Downspout
1,5,6, and 7 drain directly to Pipe A. Pipe A will be composed of 6” PVC pipe at 2%. Table 3 shows flow
contributions to Pipe A, as well as capacity. Runoff is routed to the drywell. See Appendix C for Pipe A
profile, and Appendix E for Pipe flow calculations. Runoff amounts are 100-year events.
Table 3. Pipe A Flows
3.2.2 Pipe B
Pipe B captures runoff from Inlet 8 and Downspouts 2, 3, 4, and 8. As a result, Pipe B will be composed
of 4” PVC pipe at 2%. Table 4 shows flow contributions to Pipe B, as well as capacity. Runoff is routed
to the drywell. See Appendix C for Pipe B profile, and Appendix E for Pipe flow calculations. Runoff
amounts are 100-year events.
Table 4. Pipe B Flows
3.2.3 Pipe C
Pipe C is fed by TD 1, which then routes runoff to the drywell. As a result, Pipe C will be composed of 4”
PVC pipe at 2%. Table 5 shows flow contributions to Pipe C, as well as capacity. See Appendix C for
Pipe C profile, and Appendix E for Pipe flow calculations. Runoff amounts are 100-year events.
INLET FLOW (CFS)
Inlet 1 0.001
Inlet 2 0.010
Inlet 3 0.005
Inlet 4 0.002
Inlet 5 0.002
TD 2 0.029
TD 3 0.018
TD 4 0.008
TD 5 0.007
PB:2 0.22
TOTAL:0.301
Capacity (cfs):0.84
6" PVC 2% Slope
PIPE A
INLET FLOW (CFS)
Inlet 8 0.004
PB:2 0.187
TOTAL:0.191
Capacity (cfs):0.277
4" PVC 2% Slope
PIPE B
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Table 5. Pipe C Flows
3.2.4 Pipe D
Pipe D serves as an outlet for the drywell. Pipe D will route drywell overflow to the cities storm sewer
system. Pipe D will have a 2.75-in hole drilled into a 4-in PVC cap in order to control flow to a rate of
0.285 cfs (100-year flow rate). Pipe D will be composed of 4” PVC at 5.83%.
3.3 Inlet Calculations
Eight Inlets will be installed in order to route runoff to the Drywell. Each Inlet is described below. In ad-
dition, a summary has been provided in Table 6. All inlets are located in Basin PB:1, and will be 4”
Round Brass Grates. See Appendix C for grate detail.
Table 6. Inlet Properties
3.3.1 Inlet 1
Inlet 1 will be a 4” Round Brass Grates, and will capture 0.001 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
3.3.2 Inlet 2
Inlet 2 will be a 4” Round Brass Grates, and will capture 0.010 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
3.3.3 Inlet 3
Inlet 3 will be a 4” Round Brass Grates, and will capture 0.005 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
3.3.4 Intet 4
Inlet 4 will be a 4” Round Brass Grates, and will capture 0.002 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
3.3.5 Inlet 5
Inlet 5 will be a 4” Round Brass Grates, and will capture 0.002 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
INLET FLOW (CFS)
TD:1 0.029
TOTAL:0.029
Capacity (cfs):0.277
PIPE C
4" PVC 2% Slope
NAME AREA (SF)BASIN AREA % OF AREA BASIN FLOW (CFS)INLET FLOW (CFS)
Inlet 1 16 3626.7 0.004 0.289 0.001
Inlet 2 126 3626.7 0.035 0.289 0.010
Inlet 3 59 3626.7 0.016 0.289 0.005
Inlet 4 28 3626.7 0.008 0.289 0.002
Inlet 5 29 3626.7 0.008 0.289 0.002
Inlet 6
Inlet 7
Inlet 8 52.34 3626.7 0.014 0.289 0.004
Nusiance
Nusiance
INLET FLOWS
Inlet Type
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
4" Round Brass Grate
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3.3.6 Inlet 6
Inlet 6 is located under roof cover and captures nuisance flows from the covered planting area.
3.3.7 Inlet 7
Inlet 7 is located under roof cover and captures nuisance flows from the covered planting area.
3.3.8 Inlet 8
Inlet 5 will be a 4” Round Brass Grates, and will capture 0.004 cfs of runoff. This inlet provides a 50%
flow capacity of 0.018 cfs according to NDS. As a result, the inlet has adequate flow capacity.
3.4 Trench Drain Calculations
Five trench drains (“TD”) will be installed in order to route runoff to the Drywell. Each trench drain is
described below. In addition, a summary has been provided in Table 7. All trench drains are located in
Basin PB:1, and will be Zurn Z706-HDS. See Appendix C for trench drain details.
Table 7. Trench Drain Properties
3.4.1 TD:1
TD:1 captures runoff from the driveway area, capturing 0.059 cfs of runoff. Runoff is then routed to the
drywell via Pipe C. TD:1 is 12.87 ft long, resulting in a capacity of 0.94 cfs. As a result, TD:1 has ade-
quate flow capacity.
3.4.2 TD:2
TD:2 captures runoff from the southern patio, capturing 0.029 cfs of runoff. Runoff is then routed to the
drywell via Pipe A. TD:2 is 25 ft long, resulting in a capacity of 1.83 cfs. As a result, TD:2 has adequate
flow capacity.
3.4.3 TD:3
TD:3 captures runoff from the west patio, capturing 0.018 cfs of runoff. Runoff is then routed to the dry-
well via Pipe A. TD:3 is 15.5 ft long, resulting in a capacity of 1.13 cfs. As a result, TD:3 has adequate
flow capacity.
3.4.4 TD:4
TD:4 captures runoff from the west patio, capturing 0.008 cfs of runoff. Runoff is then routed to the dry-
well via Pipe A. TD:4 is 21.28 ft long, resulting in a capacity of 1.55 cfs. As a result, TD:4 has adequate
flow capacity.
NAME AREA (SF)BASIN AREA % OF AREA BASIN FLOW (CFS)TD length (ft)TD Q(cfs)/ft TD Q total (cfs)Q Required (cfs)Inlet Type
TD 1 736 3626.7 0.20 0.289 12.87 0.073 0.94 0.059 Zurn Z706-HDS
TD 2 360 3626.7 0.10 0.289 25 0.073 1.83 0.029 Zurn Z706-HDS
TD 3 221 3626.7 0.06 0.289 15.5 0.073 1.13 0.018 Zurn Z706-HDS
TD 4 104 3626.7 0.03 0.289 21.28 0.073 1.55 0.008 Zurn Z706-HDS
TD 5 89 3626.7 0.02 0.289 10.04 0.073 0.73 0.007 Zurn Z706-HDS
TRENCH DRAIN FLOWS
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3.4.5 TD:5
TD:5 captures runoff from the southern patio, capturing 0.007 cfs of runoff. Runoff is then routed to the
drywell via Pipe A. TD:5 is 10.04 ft long, resulting in a capacity of 0.73 cfs. As a result, TD:5 has ade-
quate flow capacity.
3.5 Drywell
The drywell will have a diameter of 6 ft, and will feature 1 ft of perc. ring, 2 ft solid of ring, a 0.66 ft
thick sediment trap, and a 2 ft cone. This results in a total height of 5.66 ft. The drywell will have three
inlets (Pipe A,B, and C). The drywell will have one outlet (Pipe D) with an invert elevation of 7943.10 ft.
The drywell will be placed in the driveway with a rim elevation at 7944.79 ft. The drywell and gravel sur-
round provides a volume of 226 cf, which is adequate for WQCV. See Appendix C for drywell detail, and
Appendix E for volume calculations.
The URMP defines the minimum percolation area based on a minimum percolation time, the volume to
percolate and the hydraulic conductivity. The percolation test showed a minimum percolation rate of 3.3
in/min or a hydraulic conductivity of 4.21X10-4 ft/s (units conversion). The 100-year storm event to be
stored is 165 cf. Therefore, the percolation area required by the drywell is 9.08 square feet. With a cir-
cumference of 18.84 ft, a total of 0.48 feet of perc depth is required. The perc depth provided is 1-ft.
As described above, Pipe D will act as the detention system outlet. A cap will be added to the end of Pipe
D and a hole with a diameter of 2.75-in will be drilled into the cap. This cap and hole will serve as the
control orifice.
3.6 Operation and Maintenance
The following maintenance recommendations for dry wells can be found on page 8-118 of the URMP.
Dry wells must be inspected and maintained yearly to remove sediment and debris that is washed into
them. A maintenance plan shall be submitted to the City in the Drainage Report describing the mainte-
nance schedule that will be undertaken by the owners of the new residence or building as part of the as-
built process. The as-built operation and maintenance plan must include:
Minimum inspection and maintenance requirements include the following:
• Inspect dry wells as annually and after every storm exceeding 0.5 inches.
• Dispose of sediment, debris/trash, and any other waste material removed from a dry well at suita-
ble disposal sites and in compliance with local, state, and federal waste regulations.
• Routinely evaluate the drain-down time of the dry well to ensure the maximum time of 24 hours
is not being exceeded. If drain-down times are exceeding the maximum, drain the dry well via
pumping and clean out the percolation area (the percolation barrel may be jetted to remove sedi-
ment accumulated in perforations). Consider drilling additional perforations in the barrel. If slow
drainage persists, the system may need to be replaced.
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Appendix A--NRCS Soils Report
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United States
Department of
Agriculture
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Custom Soil Resource
Report for
Aspen-Gypsum Area,
Colorado, Parts of Eagle,
Garfield, and Pitkin
Counties
Natural
Resources
Conservation
Service
November 6, 2017
08/30/2018
Preface
Soil surveys contain information that affects land use planning in survey areas.
They highlight soil limitations that affect various land uses and provide information
about the properties of the soils in the survey areas. Soil surveys are designed for
many different users, including farmers, ranchers, foresters, agronomists, urban
planners, community officials, engineers, developers, builders, and home buyers.
Also, conservationists, teachers, students, and specialists in recreation, waste
disposal, and pollution control can use the surveys to help them understand,
protect, or enhance the environment.
Various land use regulations of Federal, State, and local governments may impose
special restrictions on land use or land treatment. Soil surveys identify soil
properties that are used in making various land use or land treatment decisions.
The information is intended to help the land users identify and reduce the effects of
soil limitations on various land uses. The landowner or user is responsible for
identifying and complying with existing laws and regulations.
Although soil survey information can be used for general farm, local, and wider area
planning, onsite investigation is needed to supplement this information in some
cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/
portal/nrcs/main/soils/health/) and certain conservation and engineering
applications. For more detailed information, contact your local USDA Service Center
(https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil
Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?
cid=nrcs142p2_053951).
Great differences in soil properties can occur within short distances. Some soils are
seasonally wet or subject to flooding. Some are too unstable to be used as a
foundation for buildings or roads. Clayey or wet soils are poorly suited to use as
septic tank absorption fields. A high water table makes a soil poorly suited to
basements or underground installations.
The National Cooperative Soil Survey is a joint effort of the United States
Department of Agriculture and other Federal agencies, State agencies including the
Agricultural Experiment Stations, and local agencies. The Natural Resources
Conservation Service (NRCS) has leadership for the Federal part of the National
Cooperative Soil Survey.
Information about soils is updated periodically. Updated information is available
through the NRCS Web Soil Survey, the site for official soil survey information.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its
programs and activities on the basis of race, color, national origin, age, disability,
and where applicable, sex, marital status, familial status, parental status, religion,
sexual orientation, genetic information, political beliefs, reprisal, or because all or a
part of an individual's income is derived from any public assistance program. (Not
all prohibited bases apply to all programs.) Persons with disabilities who require
2
08/30/2018
alternative means for communication of program information (Braille, large print,
audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice
and TDD). To file a complaint of discrimination, write to USDA, Director, Office of
Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or
call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity
provider and employer.
3
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Contents
Preface....................................................................................................................2
How Soil Surveys Are Made..................................................................................5
Soil Map..................................................................................................................8
Soil Map................................................................................................................9
Legend................................................................................................................10
Map Unit Legend................................................................................................12
Map Unit Descriptions........................................................................................12
Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin
Counties...................................................................................................14
108—Uracca, moist-Mergel complex, 6 to 12 percent slopes, extremely...14
References............................................................................................................16
4
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How Soil Surveys Are Made
Soil surveys are made to provide information about the soils and miscellaneous
areas in a specific area. They include a description of the soils and miscellaneous
areas and their location on the landscape and tables that show soil properties and
limitations affecting various uses. Soil scientists observed the steepness, length,
and shape of the slopes; the general pattern of drainage; the kinds of crops and
native plants; and the kinds of bedrock. They observed and described many soil
profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The
profile extends from the surface down into the unconsolidated material in which the
soil formed or from the surface down to bedrock. The unconsolidated material is
devoid of roots and other living organisms and has not been changed by other
biological activity.
Currently, soils are mapped according to the boundaries of major land resource
areas (MLRAs). MLRAs are geographically associated land resource units that
share common characteristics related to physiography, geology, climate, water
resources, soils, biological resources, and land uses (USDA, 2006). Soil survey
areas typically consist of parts of one or more MLRA.
The soils and miscellaneous areas in a survey area occur in an orderly pattern that
is related to the geology, landforms, relief, climate, and natural vegetation of the
area. Each kind of soil and miscellaneous area is associated with a particular kind
of landform or with a segment of the landform. By observing the soils and
miscellaneous areas in the survey area and relating their position to specific
segments of the landform, a soil scientist develops a concept, or model, of how they
were formed. Thus, during mapping, this model enables the soil scientist to predict
with a considerable degree of accuracy the kind of soil or miscellaneous area at a
specific location on the landscape.
Commonly, individual soils on the landscape merge into one another as their
characteristics gradually change. To construct an accurate soil map, however, soil
scientists must determine the boundaries between the soils. They can observe only
a limited number of soil profiles. Nevertheless, these observations, supplemented
by an understanding of the soil-vegetation-landscape relationship, are sufficient to
verify predictions of the kinds of soil in an area and to determine the boundaries.
Soil scientists recorded the characteristics of the soil profiles that they studied. They
noted soil color, texture, size and shape of soil aggregates, kind and amount of rock
fragments, distribution of plant roots, reaction, and other features that enable them
to identify soils. After describing the soils in the survey area and determining their
properties, the soil scientists assigned the soils to taxonomic classes (units).
Taxonomic classes are concepts. Each taxonomic class has a set of soil
characteristics with precisely defined limits. The classes are used as a basis for
comparison to classify soils systematically. Soil taxonomy, the system of taxonomic
classification used in the United States, is based mainly on the kind and character
of soil properties and the arrangement of horizons within the profile. After the soil
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scientists classified and named the soils in the survey area, they compared the
individual soils with similar soils in the same taxonomic class in other areas so that
they could confirm data and assemble additional data based on experience and
research.
The objective of soil mapping is not to delineate pure map unit components; the
objective is to separate the landscape into landforms or landform segments that
have similar use and management requirements. Each map unit is defined by a
unique combination of soil components and/or miscellaneous areas in predictable
proportions. Some components may be highly contrasting to the other components
of the map unit. The presence of minor components in a map unit in no way
diminishes the usefulness or accuracy of the data. The delineation of such
landforms and landform segments on the map provides sufficient information for the
development of resource plans. If intensive use of small areas is planned, onsite
investigation is needed to define and locate the soils and miscellaneous areas.
Soil scientists make many field observations in the process of producing a soil map.
The frequency of observation is dependent upon several factors, including scale of
mapping, intensity of mapping, design of map units, complexity of the landscape,
and experience of the soil scientist. Observations are made to test and refine the
soil-landscape model and predictions and to verify the classification of the soils at
specific locations. Once the soil-landscape model is refined, a significantly smaller
number of measurements of individual soil properties are made and recorded.
These measurements may include field measurements, such as those for color,
depth to bedrock, and texture, and laboratory measurements, such as those for
content of sand, silt, clay, salt, and other components. Properties of each soil
typically vary from one point to another across the landscape.
Observations for map unit components are aggregated to develop ranges of
characteristics for the components. The aggregated values are presented. Direct
measurements do not exist for every property presented for every map unit
component. Values for some properties are estimated from combinations of other
properties.
While a soil survey is in progress, samples of some of the soils in the area generally
are collected for laboratory analyses and for engineering tests. Soil scientists
interpret the data from these analyses and tests as well as the field-observed
characteristics and the soil properties to determine the expected behavior of the
soils under different uses. Interpretations for all of the soils are field tested through
observation of the soils in different uses and under different levels of management.
Some interpretations are modified to fit local conditions, and some new
interpretations are developed to meet local needs. Data are assembled from other
sources, such as research information, production records, and field experience of
specialists. For example, data on crop yields under defined levels of management
are assembled from farm records and from field or plot experiments on the same
kinds of soil.
Predictions about soil behavior are based not only on soil properties but also on
such variables as climate and biological activity. Soil conditions are predictable over
long periods of time, but they are not predictable from year to year. For example,
soil scientists can predict with a fairly high degree of accuracy that a given soil will
have a high water table within certain depths in most years, but they cannot predict
that a high water table will always be at a specific level in the soil on a specific date.
After soil scientists located and identified the significant natural bodies of soil in the
survey area, they drew the boundaries of these bodies on aerial photographs and
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identified each as a specific map unit. Aerial photographs show trees, buildings,
fields, roads, and rivers, all of which help in locating boundaries accurately.
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Soil Map
The soil map section includes the soil map for the defined area of interest, a list of
soil map units on the map and extent of each map unit, and cartographic symbols
displayed on the map. Also presented are various metadata about data used to
produce the map, and a description of each soil map unit.
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9
Custom Soil Resource Report
Soil Map
43391504339160433917043391804339190433920043392104339220433923043392404339250433926043392704339150433916043391704339180433919043392004339210433922043392304339240433925043392604339270343640 343650 343660 343670 343680 343690 343700 343710 343720 343730
343640 343650 343660 343670 343680 343690 343700 343710 343720 343730
39° 11' 19'' N 106° 48' 37'' W39° 11' 19'' N106° 48' 33'' W39° 11' 14'' N
106° 48' 37'' W39° 11' 14'' N
106° 48' 33'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 30 60 120 180
Feet
0 5 10 20 30
Meters
Map Scale: 1:627 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
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MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Aspen-Gypsum Area, Colorado, Parts of
Eagle, Garfield, and Pitkin Counties
Survey Area Data: Version 8, Oct 10, 2017
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Dec 31, 2009—Feb
16, 2017
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
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MAP LEGEND MAP INFORMATION
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
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Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
108 Uracca, moist-Mergel complex,
6 to 12 percent slopes,
extremely
1.7 100.0%
Totals for Area of Interest 1.7 100.0%
Map Unit Descriptions
The map units delineated on the detailed soil maps in a soil survey represent the
soils or miscellaneous areas in the survey area. The map unit descriptions, along
with the maps, can be used to determine the composition and properties of a unit.
A map unit delineation on a soil map represents an area dominated by one or more
major kinds of soil or miscellaneous areas. A map unit is identified and named
according to the taxonomic classification of the dominant soils. Within a taxonomic
class there are precisely defined limits for the properties of the soils. On the
landscape, however, the soils are natural phenomena, and they have the
characteristic variability of all natural phenomena. Thus, the range of some
observed properties may extend beyond the limits defined for a taxonomic class.
Areas of soils of a single taxonomic class rarely, if ever, can be mapped without
including areas of other taxonomic classes. Consequently, every map unit is made
up of the soils or miscellaneous areas for which it is named and some minor
components that belong to taxonomic classes other than those of the major soils.
Most minor soils have properties similar to those of the dominant soil or soils in the
map unit, and thus they do not affect use and management. These are called
noncontrasting, or similar, components. They may or may not be mentioned in a
particular map unit description. Other minor components, however, have properties
and behavioral characteristics divergent enough to affect use or to require different
management. These are called contrasting, or dissimilar, components. They
generally are in small areas and could not be mapped separately because of the
scale used. Some small areas of strongly contrasting soils or miscellaneous areas
are identified by a special symbol on the maps. If included in the database for a
given area, the contrasting minor components are identified in the map unit
descriptions along with some characteristics of each. A few areas of minor
components may not have been observed, and consequently they are not
mentioned in the descriptions, especially where the pattern was so complex that it
was impractical to make enough observations to identify all the soils and
miscellaneous areas on the landscape.
The presence of minor components in a map unit in no way diminishes the
usefulness or accuracy of the data. The objective of mapping is not to delineate
pure taxonomic classes but rather to separate the landscape into landforms or
landform segments that have similar use and management requirements. The
delineation of such segments on the map provides sufficient information for the
development of resource plans. If intensive use of small areas is planned, however,
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onsite investigation is needed to define and locate the soils and miscellaneous
areas.
An identifying symbol precedes the map unit name in the map unit descriptions.
Each description includes general facts about the unit and gives important soil
properties and qualities.
Soils that have profiles that are almost alike make up a soil series. Except for
differences in texture of the surface layer, all the soils of a series have major
horizons that are similar in composition, thickness, and arrangement.
Soils of one series can differ in texture of the surface layer, slope, stoniness,
salinity, degree of erosion, and other characteristics that affect their use. On the
basis of such differences, a soil series is divided into soil phases. Most of the areas
shown on the detailed soil maps are phases of soil series. The name of a soil phase
commonly indicates a feature that affects use or management. For example, Alpha
silt loam, 0 to 2 percent slopes, is a phase of the Alpha series.
Some map units are made up of two or more major soils or miscellaneous areas.
These map units are complexes, associations, or undifferentiated groups.
A complex consists of two or more soils or miscellaneous areas in such an intricate
pattern or in such small areas that they cannot be shown separately on the maps.
The pattern and proportion of the soils or miscellaneous areas are somewhat similar
in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example.
An association is made up of two or more geographically associated soils or
miscellaneous areas that are shown as one unit on the maps. Because of present
or anticipated uses of the map units in the survey area, it was not considered
practical or necessary to map the soils or miscellaneous areas separately. The
pattern and relative proportion of the soils or miscellaneous areas are somewhat
similar. Alpha-Beta association, 0 to 2 percent slopes, is an example.
An undifferentiated group is made up of two or more soils or miscellaneous areas
that could be mapped individually but are mapped as one unit because similar
interpretations can be made for use and management. The pattern and proportion
of the soils or miscellaneous areas in a mapped area are not uniform. An area can
be made up of only one of the major soils or miscellaneous areas, or it can be made
up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example.
Some surveys include miscellaneous areas. Such areas have little or no soil
material and support little or no vegetation. Rock outcrop is an example.
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Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin
Counties
108—Uracca, moist-Mergel complex, 6 to 12 percent slopes, extremely
Map Unit Setting
National map unit symbol: jq4h
Elevation: 6,800 to 8,400 feet
Mean annual precipitation: 16 to 19 inches
Mean annual air temperature: 40 to 43 degrees F
Frost-free period: 75 to 95 days
Farmland classification: Not prime farmland
Map Unit Composition
Uracca, moist, and similar soils: 50 percent
Mergel and similar soils: 40 percent
Minor components: 10 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Uracca, Moist
Setting
Landform: Valley sides, alluvial fans, structural benches
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Mixed alluvium derived from igneous and metamorphic rock
Typical profile
H1 - 0 to 8 inches: cobbly sandy loam
H2 - 8 to 15 inches: very cobbly sandy clay loam
H3 - 15 to 60 inches: extremely cobbly loamy sand
Properties and qualities
Slope: 6 to 12 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Runoff class: Medium
Capacity of the most limiting layer to transmit water (Ksat): Moderately high to
high (0.20 to 2.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 10 percent
Available water storage in profile: Very low (about 2.6 inches)
Interpretive groups
Land capability classification (irrigated): None specified
Land capability classification (nonirrigated): 6e
Hydrologic Soil Group: B
Ecological site: Stony Loam (R048AY237CO)
Other vegetative classification: Stony Loam (null_82)
Hydric soil rating: No
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Description of Mergel
Setting
Landform: Alluvial fans, structural benches, valley sides
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Glacial outwash
Typical profile
H1 - 0 to 8 inches: cobbly loam
H2 - 8 to 20 inches: very cobbly sandy loam
H3 - 20 to 60 inches: extremely stony sandy loam
Properties and qualities
Slope: 6 to 12 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water (Ksat): Moderately high to
high (0.60 to 6.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 10 percent
Available water storage in profile: Low (about 3.3 inches)
Interpretive groups
Land capability classification (irrigated): 4s
Land capability classification (nonirrigated): 4s
Hydrologic Soil Group: A
Ecological site: Stony Loam (R048AY237CO)
Other vegetative classification: Stony Loam (null_82)
Hydric soil rating: No
Minor Components
Other soils
Percent of map unit: 10 percent
Hydric soil rating: No
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References
American Association of State Highway and Transportation Officials (AASHTO).
2004. Standard specifications for transportation materials and methods of sampling
and testing. 24th edition.
American Society for Testing and Materials (ASTM). 2005. Standard classification of
soils for engineering purposes. ASTM Standard D2487-00.
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of
wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife
Service FWS/OBS-79/31.
Federal Register. July 13, 1994. Changes in hydric soils of the United States.
Federal Register. September 18, 2002. Hydric soils of the United States.
Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric
soils in the United States.
National Research Council. 1995. Wetlands: Characteristics and boundaries.
Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service.
U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/
nrcs/detail/national/soils/?cid=nrcs142p2_054262
Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for
making and interpreting soil surveys. 2nd edition. Natural Resources Conservation
Service, U.S. Department of Agriculture Handbook 436. http://
www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577
Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of
Agriculture, Natural Resources Conservation Service. http://
www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580
Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and
Delaware Department of Natural Resources and Environmental Control, Wetlands
Section.
United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of
Engineers wetlands delineation manual. Waterways Experiment Station Technical
Report Y-87-1.
United States Department of Agriculture, Natural Resources Conservation Service.
National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/
home/?cid=nrcs142p2_053374
United States Department of Agriculture, Natural Resources Conservation Service.
National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/
detail/national/landuse/rangepasture/?cid=stelprdb1043084
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United States Department of Agriculture, Natural Resources Conservation Service.
National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/
nrcs/detail/soils/scientists/?cid=nrcs142p2_054242
United States Department of Agriculture, Natural Resources Conservation Service.
2006. Land resource regions and major land resource areas of the United States,
the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook
296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?
cid=nrcs142p2_053624
United States Department of Agriculture, Soil Conservation Service. 1961. Land
capability classification. U.S. Department of Agriculture Handbook 210. http://
www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf
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2
Appendix B--FEMA FIRM Map
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3
Appendix C--Plan Set
08/30/2018
11/22/2017DATE OF PUBLICATIONC100COVER SHEET302 PARK
302 PARK AVE. ASPEN, CO 81611PERMIT SETWOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COM302 PARK302 PARK AVE. ASPEN, CO 81611NOTES:1.ALL MATERIALS, WORKMANSHIP, AND CONSTRUCTION OF PUBLICIMPROVEMENTS SHALL MEET OR EXCEED THE STANDARDS ANDSPECIFICATIONS SET FORTH IN THE CITY OF ASPEN ("COA") MUNICIPALCODE, COA TECHNICAL MANUALS, AND APPLICABLESTATE AND FEDERAL REGULATIONS. WHERE THERE IS CONFLICT BETWEENTHESE PLANS AND THE TECHNICAL MANUAL OR ANY APPLICABLESTANDARDS, THE HIGHER QUALITY STANDARD SHALL APPLY. ALL UTILITYWORK SHALL BE INSPECTED AND APPROVED BY THE UTILITY.2.THE CONTRACTOR IS SPECIFICALLY CAUTIONED THAT THE LOCATIONAND/OR ELEVATION OF EXISTING UTILITIES AS SHOWN ON THESE PLANS ISBASED ON RECORDS OF THE VARIOUS UTILITY COMPANIES AND, WHEREPOSSIBLE, MEASUREMENTS TAKEN IN THE FIELD. THE INFORMATION IS NOTTO BE RELIED UPON AS BEING EXACT OR COMPLETE.3.THE CONTRACTOR SHALL HAVE ONE (1) SIGNED COPY OF THEAPPROVED PLANS, ONE (1) COPY OF THE APPROPRIATE CRITERIA ANDSPECIFICATIONS, AND A COPY OF ANY PERMITS AND EXTENSIONAGREEMENTS NEEDED FOR THE JOB ONSITE AT ALL TIMES.4.THE CONTRACTOR SHALL BE RESPONSIBLE FOR ALL ASPECTS OFSAFETY INCLUDING, BUT NOT LIMITED TO, EXCAVATION, TRENCHING,SHORING,TRAFFIC CONTROL, AND SECURITY.5.IF DURING THE CONSTRUCTION PROCESS CONDITIONS AREENCOUNTERED WHICH COULD INDICATE A SITUATION THAT IS NOTIDENTIFIED IN THE PLANS OR SPECIFICATIONS, THE CONTRACTOR SHALLCONTACT THE WOODY CREEK ENGINEERING, LLC IMMEDIATELY.6.ALL REFERENCES TO ANY PUBLISHED STANDARDS SHALL REFER TOTHE LATEST REVISION OF SAID STANDARD UNLESS SPECIFICALLY STATEDOTHERWISE.7.THE CONTRACTOR SHALL SUBMIT A TRAFFIC CONTROL PLAN INACCORDANCE WITH MUTCD TO THE APPROPRIATE RIGHT-OF-WAYAUTHORITY (TOWN, COUNTY OR STATE) FOR APPROVAL PRIOR TO ANYCONSTRUCTION ACTIVITIES WITHIN OR AFFECTING THE RIGHT-OF-WAY.THE CONTRACTOR SHALL BE RESPONSIBLE FOR PROVIDING ANY AND ALLTRAFFIC CONTROL DEVICES AS MAY BE REQUIRED BY THECONSTRUCTION ACTIVITIES.8.THE CONTRACTOR IS RESPONSIBLE FOR PROVIDING ALL LABOR ANDMATERIALS NECESSARY FOR THE COMPLETION OF THE INTENDEDIMPROVEMENTS SHOWN ON THESE DRAWINGS OR AS DESIGNATED TO BEPROVIDED, INSTALLED, OR CONSTRUCTED UNLESS SPECIFICALLYNOTED OTHERWISE.9.THE CONTRACTOR SHALL BE RESPONSIBLE FOR KEEPING ROADWAYSFREE AND CLEAR OF ALL CONSTRUCTION DEBRIS AND DIRT TRACKED FROMTHE SITE.10.THE CONTRACTOR SHALL BE RESPONSIBLE FOR RECORDING AS-BUILTINFORMATION ON A SET OF RECORD DRAWINGS KEPT ON THECONSTRUCTION SITE AND AVAILABLE AT ALL TIMES.11.DIMENSIONS FOR LAYOUT AND CONSTRUCTION ARE NOT TO BESCALED FROM ANY DRAWING. IF PERTINENT DIMENSIONS ARE NOT SHOWN,CONTACT WOODY CREEK ENGINEERING, LLC FOR CLARIFICATION ANDANNOTATE THE DIMENSION ON THE AS-BUILT RECORD DRAWINGS.15. THE CONTRACTOR SHALL COMPLY WITH ALL TERMS AND CONDITIONS OFTHE COLORADO PERMIT FOR STORM WATER DISCHARGE, THE STORMWATER MANAGEMENT PLAN, AND THE EROSION CONTROL PLAN.16.ALL STRUCTURAL EROSION CONTROL MEASURES SHALL BEINSTALLED AT THE LIMITS OF CONSTRUCTION PRIOR TO ANY OTHEREARTH-DISTURBING ACTIVITY. ALL EROSION CONTROL MEASURES SHALL BEMAINTAINED IN GOOD REPAIR BY THE CONTRACTOR UNTIL SUCH TIME ASTHE ENTIRE DISTURBED AREA IS STABILIZED WITH HARD SURFACE ORLANDSCAPING.17.THE CONTRACTOR SHALL SEQUENCE INSTALLATION OF UTILITIES INSUCH A MANNER AS TO MINIMIZE POTENTIAL UTILITY CONFLICTS. INGENERAL, STORM SEWER AND SANITARY SEWER SHOULD BECONSTRUCTED PRIOR TO INSTALLATION OF THE WATER LINES AND DRYUTILITIES.VICINITY MAP0100 200 400 800Scale: 1" = 200'N11/22/20177/2/2018 PERMIT REV 108/30/2018
EB:1AREA:6562.5 SF7945.17PB:2AREA:2935.8 SFPB:1AREA:3626.7 SF794579447944
7945.1779447944
7944
0 5 10 20 40Scale: 1" = 10'NBASIN BOUNDARY7/2/2018DATE OF PUBLICATIONC200BASINS302 PARK
302 PARK AVE. ASPEN, CO 81611 WOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COMPERMIT SET11/22/2018HISTORICALPROPOSEDPERMIT REV 17/2/20181/11/20187/2/201808/30/2018
-2.0%-2.0%-1.2%794579447944 7945.287945.287944.687944.697944.697945.157944.537944.537944.737944.737944.667944.707944.697944.627944.787944.787944.697944.69TIE TO DITCH: 7940.00DRYWELLDIA.= 6 FTDEPTH = 5.7 FT2 FT GRAVEL ANNULUSRIM:7944.79OUTLET IE: 7943.42MINIMUM 10-FT FROMFOUNDATION WALL AND 10-FT FROMPROPERTY LINES9.36' of 6" PVC @ 2.00%INLET - 1RIM:7944.53SUMP:7943.19INV IN:7943.21 6" PVCINV OUT:7943.21 6" PVCINLET - 2RIM:7944.54SUMP:7941.34INV OUT:7943.34 6" PVC6.54' of 6" PVC @ 2.00%INLET - 3RIM:7944.55SUMP:7942.52INV IN:7943.02 6" PVCINV IN:7943.02 4" PVCINV OUT:7943.02 6" PVC3.41' of 4" PVC @ 2.00%16.32' of 6" PVC @ 2.00%INLET - 4RIM:7944.54SUMP:7942.20INV IN:7942.70 6" PVCINV IN:7942.70 4" PVCINV OUT:7942.70 6" PVC3.14' of 6" PVC @ 2.00%12.58' of 6" PVC @ 2.00%20.34' of 6" PVC @ 2.00%20.06' of 6" PVC @ 2.00%INLET - 5RIM:7944.60SUMP:7941.48INV IN:7941.98 6" PVCINV IN:7941.98 4" PVCINV IN:7941.98 4" PVCINV OUT:7941.98 6" PVCINLET - 6RIM:7945.04SUMP:7941.08INV IN:7941.58 4" PVCINV IN:7941.58 6" PVCINV IN:7941.58 4" PVCINV OUT:7941.58 6" PVC6.08' of 4" PVC @ 2.40%INLET - 7RIM:7945.09SUMP:7941.73INV IN:7941.73 4" PVCINV OUT:7941.73 4" PVC10.91' of 4" PVC @ 2.02%15.26' of 6" PVC @ 2.00%7944.527944.467944.467944.487944.417943.867945.17-6.1%TD:7944.42TD:7944.38TD:7944.5058.71' of 4" PVC @ 5.83%27.73' of 4" PVC @ 2.01%23.32' of 4" PVC @ 2.00%28.79' of 4" PVC @ 2.00%9.05' of 4" PVC @ 2.01%4.05' of 4" PVC @ 2.00%INV OUT:7943.37TD:1TD:2TD:4TD:3
DS - 2GU-2GU-2GU-3 GU-1
GU-4
DS-4DS - 3GU-5GU-9GU-7 GU-8
GU-6 DS - 5DS-8DS-7DS - 1DS-67945.177945.28-2.0%794379437943794179417942794279437943
7945
7944
7945794579457944 7944794479447944
7944
TD:5INLET 8RIM:7945.19SUMP:7942.95INV IN:7943.45 4"INV OUT:7943.45 4" PVC5.67' of 4" PVC @ 2.00%18.41' of 4" @ -2.00%TD:7944.50 PIPE B PIPE C PIPE D PIPE AEXISTING FOUNDATIONDRAIN PROVIDEACCESSIBLE COVEREXISTING SEWEREJECTOR PROVIDEACCESSIBLE COVER3.43' of 4" PVC @ 2.00%9.98 FT10.00 FT10.00 FT7944.6510.00 FT7943.673.11' of 4" @ 2.00%INV OUT:7943.67TD 2 CONNECTRIM:7944.42TD IN:7943.67INV OUT:7942.29 4" PVCTD 3 CONNECTRIM:7945.02TD IN:7944.4INV OUT:7941.72 4" PVCTD:7944.50TD CONNECTRIM:7944.50TD IN (S):7943.73TD IN (N):7943.80INV IN:7942.38 4" PVCTD 1 CONNECTRIM:7943.67INV OUT: 7941.77' 4"PVCTD IN: 7943.10'LIGHTWELLSEXISTING WATER. NO CHANGE.7/11/2018DATE OF PUBLICATIONC300GRADING ANDDRAINAGE302 PARK
302 PARK AVE. ASPEN, CO 81611 WOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COM0 2.5 5 10 20Scale: 1" = 5'NEXISTING CONTOURPROPOSED CONTOUR7910SPOT ELEVATION XXXX.XXCONC. = CONCRETEHP = HIGH POINTTD = TRENCH DRAINTOW=TOP OF WALLBW=BOTTOM OF WALLUTILITY SERVICEE=ELECTRICUG=UNDERGROUND GASSS=SANITARY SEWERW=WATERTel=PHONE LINECable=CABLE LINEPROPERTY LINEBUILDINGGAS METERBACKFLOW PREVENTERAND YARD HYDRANTELECTRIC METERGWEWALKWAYWALLDOWNSPOUT (DS)INLETTRENCH DRAIN (TD)GUTTER (GU)PIPEPERF. PIPENOTE:1. EXISTING UTILITIES TOREMAIN2. EXISTING TREES TOREMAINPERMIT SET11/22/2018PERMIT REV 17/2/20181/11/20187/2/201808/30/2018
ElevationStationPipe A PROFILE794079417942794379447945794679477948794979500+000+250+500+750+98INLET - 1RIM:7944.53SUMP:7943.19INV IN:7943.21 6" PVCINV OUT:7943.21 6" PVC2%INLET - 3RIM:7944.55SUMP:7942.52INV IN:7943.02 6" PVCINV IN:7943.02 4" PVCINV OUT:7943.02 6" PVC2%INLET - 4RIM:7944.54SUMP:7942.20INV IN:7942.70 6" PVCINV IN:7942.70 4" PVCINV OUT:7942.70 6" PVC2%2%2%2%INLET - 5RIM:7944.60SUMP:7941.48INV IN:7941.98 6" PVCINV IN:7941.98 4" PVCINV IN:7941.98 4" PVCINV OUT:7941.98 6" PVC2%INLET - 6RIM:7945.04SUMP:7941.08INV IN:7941.58 4" PVCINV IN:7941.58 6" PVCINV IN:7941.58 4" PVCINV OUT:7941.58 6" PVCElevationStationPIPE B PROFILE794079417942794379447945794679477948794979500+000+250+500+751+001+102%2%2%2%ElevationStationPIPE C PROFILE794079417942794379447945794679477948794979500+000+18ElevationStationPipe D PROFILE794079417942794379447945794679477948794979500+000+250+500+597/2/2018DATE OF PUBLICATIONC400DETAILS302 PARK
302 PARK AVE. ASPEN, CO 81611 WOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COMPERMIT SET11/22/2018PERMIT REV 17/2/20181/11/20187/2/201808/30/2018
ABC4-IN OUTLET , CAPPED2.75-IN DIAM. HOLE DRILLEDINTO CENTER FOR FLOW CONTROLQA=0.285 CFSEXISTING BOULDERSOUTLET DETAIL7/2/2018DATE OF PUBLICATIONC500DETAILS302 PARK
302 PARK AVE. ASPEN, CO 81611 WOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COMPERMIT SET11/22/2018PERMIT REV 17/2/20181/11/20187/2/201808/30/2018
794579447944
7945.1779447944
7944
TRACKING PADSEDIMENT FENCE9.98 FT10.00 FT10.00 FT10.00 FTLIGHTWELLS0 2.5 5 10 20Scale: 1" = 5'NUTILITY SERVICEE=ELECTRICUG=UNDERGROUND GASSS=SANITARY SEWERW=WATERTel=PHONE LINECable=CABLE LINEGAS METERBACKFLOW PREVENTERAND YARD HYDRANTELECTRIC METERGWE7/11/2018DATE OF PUBLICATIONC600EROSION ANDSEDIMENTCONTROL302 PARK
302 PARK AVE. ASPEN, CO 81611 WOODY CREEK ENGINEERING, LLCP.O. BOX 575WOODY CREEK, COLORADO 81656(P): 970-429-8297WOODYCREEKENGINEERING.COMPERMIT SET11/22/2018PERMIT REV 17/2/20181/11/20187/2/201808/30/2018
4
Appendix D--Hydrologic Calculations
08/30/2018
6938465.xls Page 1
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title:1300 RIVERSIDE
Catchment ID:PB:1
I.Catchment Hydrologic Data
Catchment ID =PB:1
Area =0.083 Acres
Percent Imperviousness =57.00 %
NRCS Soil Type =B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr =5 years (input return period for design storm)
C1 =88.80 (input the value of C1)
C2=10.00 (input the value of C2)
C3=1.052 (input the value of C3)
P1=0.64 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =0.39
Overide Runoff Coefficient, C =(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 =0.39
Overide 5-yr. Runoff Coefficient, C =(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/Short Nearly Grassed Paved Areas &
Type Meadow Field Pasture/Bare Swales/Shallow Paved Swales
Lawns Ground Waterways (Sheet Flow)
Conveyance 2.5 5 7 10 15 20
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey-Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 5.0000 5 0.39 N/A 0.23 0.37
1
2
3
4
5
Sum 5 Computed Tc =0.37
Regional Tc =10.03
User-Entered Tc =5.00
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =4.85 inch/hr Peak Flowrate, Qp =0.158 cfs
Rainfall Intensity at Regional Tc, I =2.43 inch/hr Peak Flowrate, Qp =0.079 cfs
Rainfall Intensity at User-Defined Tc, I =3.29 inch/hr Peak Flowrate, Qp =0.107 cfs
08/30/2018
6958465.xls Page 1
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title:1300 RIVERSIDE
Catchment ID:PB:1
I.Catchment Hydrologic Data
Catchment ID =PB:1
Area =0.083 Acres
Percent Imperviousness =57.00 %
NRCS Soil Type =B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr =100 years (input return period for design storm)
C1 =88.80 (input the value of C1)
C2=10.00 (input the value of C2)
C3=1.052 (input the value of C3)
P1=1.23 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =0.55
Overide Runoff Coefficient, C =(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 =0.39
Overide 5-yr. Runoff Coefficient, C =(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/Short Nearly Grassed Paved Areas &
Type Meadow Field Pasture/Bare Swales/Shallow Paved Swales
Lawns Ground Waterways (Sheet Flow)
Conveyance 2.5 5 7 10 15 20
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey-Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 5.0000 5 0.39 N/A 0.23 0.37
1
2
3
4
5
Sum 5 Computed Tc =0.37
Regional Tc =10.03
User-Entered Tc =5.00
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =9.33 inch/hr Peak Flowrate, Qp =0.426 cfs
Rainfall Intensity at Regional Tc, I =4.67 inch/hr Peak Flowrate, Qp =0.213 cfs
Rainfall Intensity at User-Defined Tc, I =6.33 inch/hr Peak Flowrate, Qp =0.2892 cfs
08/30/2018
6998465.xls Page 1
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title:1300 RIVERSIDE
Catchment ID:PB:2
I.Catchment Hydrologic Data
Catchment ID =PB:2
Area =0.067 Acres
Percent Imperviousness =100.00 %
NRCS Soil Type =B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr =5 years (input return period for design storm)
C1 =88.80 (input the value of C1)
C2=10.00 (input the value of C2)
C3=1.052 (input the value of C3)
P1=0.64 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =0.90
Overide Runoff Coefficient, C =(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 =0.90
Overide 5-yr. Runoff Coefficient, C =(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/Short Nearly Grassed Paved Areas &
Type Meadow Field Pasture/Bare Swales/Shallow Paved Swales
Lawns Ground Waterways (Sheet Flow)
Conveyance 2.5 5 7 10 15 20
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey-Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 5.0000 5 0.90 N/A 0.78 0.11
1
2
3
4
5
Sum 5 Computed Tc =0.11
Regional Tc =10.03
User-Entered Tc =5.00
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =4.98 inch/hr Peak Flowrate, Qp =0.299 cfs
Rainfall Intensity at Regional Tc, I =2.43 inch/hr Peak Flowrate, Qp =0.146 cfs
Rainfall Intensity at User-Defined Tc, I =3.29 inch/hr Peak Flowrate, Qp =0.197 cfs
08/30/2018
6918465.xls Page 1
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title:1300 RIVERSIDE
Catchment ID:PB:2
I.Catchment Hydrologic Data
Catchment ID =PB:2
Area =0.067 Acres
Percent Imperviousness =100.00 %
NRCS Soil Type =B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr =100 years (input return period for design storm)
C1 =88.80 (input the value of C1)
C2=10.00 (input the value of C2)
C3=1.052 (input the value of C3)
P1=1.23 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =0.96
Overide Runoff Coefficient, C =(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 =0.90
Overide 5-yr. Runoff Coefficient, C =(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/Short Nearly Grassed Paved Areas &
Type Meadow Field Pasture/Bare Swales/Shallow Paved Swales
Lawns Ground Waterways (Sheet Flow)
Conveyance 2.5 5 7 10 15 20
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey-Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 5.0000 5 0.90 N/A 0.78 0.11
1
2
3
4
5
Sum 5 Computed Tc =0.11
Regional Tc =10.03
User-Entered Tc =5.00
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =9.58 inch/hr Peak Flowrate, Qp =0.613 cfs
Rainfall Intensity at Regional Tc, I =4.67 inch/hr Peak Flowrate, Qp =0.299 cfs
Rainfall Intensity at User-Defined Tc, I =6.33 inch/hr Peak Flowrate, Qp =0.4049 cfs
08/30/2018
Project Title:
Catchment ID:
I.Catchment Hydrologic Data
Catchment ID = EB:1
Area = 0.151 Acres
Percent Imperviousness = 0.00 %
NRCS Soil Type = B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr = 5 years (input return period for design storm)
C1 = 88.80 (input the value of C1)
C2= 10.00 (input the value of C2)
C3= 1.052 (input the value of C3)
P1= 0.64 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C = 0.08
Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 = 0.08
Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/ Short Nearly Grassed
Type Meadow Field Pasture/ Bare Swales/
Lawns Ground Waterways
Conveyance 2.5 5 7 10 15
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey- Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 0.0790 64 0.08 N/A 0.14 7.49
1
2
3
4
5
64 Computed Tc =7.49
Regional Tc = 10.36
User-Entered Tc = 7.49
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =2.80 inch/hr Peak Flowrate, Qp = 0.032 cfs
Rainfall Intensity at Regional Tc, I =2.39 inch/hr Peak Flowrate, Qp = 0.027 cfs
Rainfall Intensity at User-Defined Tc, I =2.80 inch/hr Peak Flowrate, Qp = 0.032 cfs
(Sheet Flow)
20
Shallow Paved Swales
Sum
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
1300 RIVERSIDE
EB:1
Paved Areas &
5YR-EB1 Page 108/30/2018
6978465.xls Page 1
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title:1300 RIVERSIDE
Catchment ID:EB:1
I.Catchment Hydrologic Data
Catchment ID =EB:1
Area =0.151 Acres
Percent Imperviousness =0.00 %
NRCS Soil Type =B A, B, C, or D
II.Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3
Design Storm Return Period, Tr =100 years (input return period for design storm)
C1 =88.80 (input the value of C1)
C2=10.00 (input the value of C2)
C3=1.052 (input the value of C3)
P1=1.23 inches (input one-hr precipitation--see Sheet "Design Info")
III.Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =0.35
Overide Runoff Coefficient, C =(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C-5 =0.08
Overide 5-yr. Runoff Coefficient, C =(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
NRCS Land Heavy Tillage/Short Nearly Grassed Paved Areas &
Type Meadow Field Pasture/Bare Swales/Shallow Paved Swales
Lawns Ground Waterways (Sheet Flow)
Conveyance 2.5 5 7 10 15 20
Calculations:Reach Slope Length 5-yr NRCS Flow Flow
ID S L Runoff Convey-Velocity Time
Coeff ance V Tf
ft/ft ft C-5 fps minutes
input input output input output output
Overland 0.0790 64 0.08 N/A 0.14 7.49
1
2
3
4
5
Sum 64 Computed Tc =7.49
Regional Tc =10.36
User-Entered Tc =7.49
IV.Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I =5.38 inch/hr Peak Flowrate, Qp =0.284 cfs
Rainfall Intensity at Regional Tc, I =4.59 inch/hr Peak Flowrate, Qp =0.242 cfs
Rainfall Intensity at User-Defined Tc, I =5.38 inch/hr Peak Flowrate, Qp =0.2844 cfs
08/30/2018
City of Aspen Urban Runoff Management Plan
Chapter 8 – Water Quality 8-30 Rev 11/2014
Figure 8.13 Aspen Water Quality Capture Volume
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100WQCV (watershed-inches) Effective Imperviousness of Tributary Area to BMP (percent)
WQCV
SF
08/30/2018
5
Appendix E--Hydraulic Calculations
08/30/2018
Orifice Calculator
Qallow (cfs)=0.285
Co =0.6
Ho (ft)=2.05
Ao (sf)=0.04134
Ao (in^2)=5.953005
D (in)=2.753806
08/30/2018
Channel Report
Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Thursday, Jun 29 2017
<Name>
Circular
Diameter (ft) = 0.33
Invert Elev (ft) = 100.00
Slope (%) = 2.00
N-Value = 0.012
Calculations
Compute by: Q vs Depth
No. Increments = 10
Highlighted
Depth (ft) = 0.26
Q (cfs) = 0.277
Area (sqft) = 0.07
Velocity (ft/s) = 3.78
Wetted Perim (ft) = 0.73
Crit Depth, Yc (ft) = 0.30
Top Width (ft) = 0.26
EGL (ft) = 0.49
0 1
Elev (ft)Section
99.75
100.00
100.25
100.50
100.75
101.00
Reach (ft)
08/30/2018
Channel Report
Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Monday, Oct 23 2017
<Name>
Circular
Diameter (ft) = 0.50
Invert Elev (ft) = 100.00
Slope (%) = 2.00
N-Value = 0.012
Calculations
Compute by: Q vs Depth
No. Increments = 10
Highlighted
Depth (ft) = 0.40
Q (cfs) = 0.840
Area (sqft) = 0.17
Velocity (ft/s) = 4.99
Wetted Perim (ft) = 1.11
Crit Depth, Yc (ft) = 0.46
Top Width (ft) = 0.40
EGL (ft) = 0.79
0 1
Elev (ft)Section
99.75
100.00
100.25
100.50
100.75
101.00
Reach (ft)
08/30/2018
6
Appendix F—Detention Calculations
08/30/2018
Project:302 Park Ave.
Impervious Area:4994.8 sf
WQCV
WQCV Depth:0.255 in
WQCV Volume:106.14 cf
Factor of Safety:1.50
WQCV:159.21 cf
100-Year
100-yr Storm Depth:1.23 in
100-yr Storm Volume:511.97 cf
Factor of Safety:1.00
100-Yr Retention:511.97 cf
100-Yr Detention:165.00 cf
Drywell Volume Calculation
Interior Diameter 6 ft
Exterior Diameter 7.04 ft
Gravel Ring 2 ft
Interior Volume 28.26 cf/ft
Gravel Volume
--Exterior Area 95.68 sf
--Interior Area 38.91 sf
--Gravel Area 56.77 sf
Void 0.3
Volume 17.03 cf/ft
Depth 5 ft
Volume
Drywell 141.30 cf
Gravel 85.16 cf
Total 226.46 cf
Percolation Area Calculation
AP=(Vr)/(K)(43200)
Where
AP: Total area of the sides of the percolation area, square feet
Vr: Runoff volume, cubic feet
08/30/2018
K: Hydraulic conductivity, (ft/s)
K:
Percolation Rate (Geotech):3.3 in/min
Resulting K:0.000420875 ft/s
Vr:165.00 cf
AP=9.08 square feet required
Area (1in hole)0.785 square inches
Number of 1 inch holes:12
Circumference 18.84 ft/drywell
Min Perc Depth (ft)0.48 ft
Perc Depth Provided (ft)1 ft
08/30/2018