HomeMy WebLinkAboutWORTHINGTON STORAGE - PDP220003 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT
PRELIMINARY DRAINAGE REPORT
WORTHINGTON SELF STORAGE
FEBRUARY 23, 2022
NORTHERNENGINEERING.COM
970.221.4158
FORT COLLINS
GREELEY
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FORT COLLINS | GREELEY COVER LETTER
February 23, 2022
City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, CO 80521
RE: PRELIMINARY DRAINAGE REPORT FOR
WORTHINGTON SELF STORAGE
Dear Staff:
Northern Engineering is pleased to submit this Preliminary Drainage Report for your review. This report
accompanies the combined Preliminary Plan submittal for the proposed Worthington Self Storage project.
This report has been prepared in accordance with the City of Fort Collins Stormwater Criteria Manual (FCSCM)
and serves to document the stormwater impacts associated with the proposed Worthington Enclosed Self
Storage project.
We understand that review by the City of Fort Collins is to assure general compliance with standardized criteria
contained in the manual. If you should have any questions as you review this report, please feel free to contact
us.
Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
MASON RUEBEL, PE
Project Engineer
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FORT COLLINS | GREELEY TABLE OF CONTENTS
TABLE OF CONTENTS
I. I. GENERAL LOCATION AND DESCRIPTION .......................................................... 1
II. II. DRAINAGE BASINS AND SUB-BASINS ............................................................... 3
III. III. DRAINAGE DESIGN CRITERIA .......................................................................... 4
IV. IV. DRAINAGE FACILITY DESIGN ........................................................................... 6
V. V. CONCLUSIONS .............................................................................................. 8
VI. VI. REFERENCES ................................................................................................ 9
TABLES AND FIGURES
FIGURE 1: AERIAL PHOTOGRAPH ...........................................................................................2
FIGURE 2: REGULATORY FLOODPLAINS ................................................................................3
TABLE 1: DETENTION POND SUMMARY .................................................................................8
TABLE 2: CHAMBER COUNT SUMMARY ..................................................................................8
APPENDICES
APPENDIX A – HYDROLOGIC COMPUTATIONS
APPENDIX B – HYDRAULIC COMPUTATIONS
APPENDIX C – DETENTION POND & WATER QUALITY COMPUTATIONS
APPENDIX D – EROSION CONTROL REPORT
APPENDIX E – USDA SOILS REPORT
APPENDIX F – EXCERPTS FROM CENTRE FOR ADVANCED TECHNOLOGY 16TH FILING
MAP POCKET
DR1 – DRAINAGE EXHIBIT
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I. GENERAL LOCATION AND DESCRIPTION
A. LOCATION
Vicinity Map
Figure 1: Vicinty Map
Worthington Self Storage project is located in the southwest quarter of Section 23, Township 7
North, Range 69 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of
Colorado.
The project site is bordered to the east by Worthington Circle. The rest of the site is surrounded
by a private road and commercial development apart of the Centre for Advanced Technology 10th
& 19th Filing.
The nearest existing major streets to the project are Worthington Circle and Centre Ave just to the
north of the project site.
A 15” storm sewer conveys stormwater from the existing project site to the north in an existing
piping system along Centre Avenue outletting into Spring Creek.
B. DESCRIPTION OF PROPERTY
The existing project site comprises of ± 3.2 acres. The existing site will be subdivided into two lots
with the proposed development on Lot 1 (1.98ac) and the existing building remaining in Lot 2
(1.22ac).
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The site is currently used as asphalt parking lot with an adjacent 1-story existing building.
A subsurface exploration report was completed by Triax Engineering, Inc. on June 4, 2021 (Triax
Project No. D21G125). According to Triax Engineering, the site generally consists of clayey sand
with groundwater at around 20-ft in depth.
According to the United States Department of Agriculture (USDA) Natural Resources
Conservation Service (NRCS) Soil Survey website:
(http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx), the site consists primarily of
Nunn Clay loam (Hydrologic Soil Group C) and Kim loam (Hydrologic Soil Group B). The
calculations assume a Hydrologic Soil Group of C. Hydrologic Soil Group C has a slow rate of
water absorption and infiltration.
The proposed development will consist of proposed 3-story enclosed mini-storage building and
three other 1-story outdoor garage storage buildings. Other proposed improvements include
asphalt drive aisles, sidewalks, and landscaping. There is no increase in impervious area with the
proposed project. Existing detention volumes will be maintained, but storage methods and
conveyance will be modified with the proposed project.
The site is currently zoned as Employment District (E) in Fort Collins. Developments surrounding
the project site are zoned as Employment as well and Neighborhood commercial district to the
east of Worthington Circle. The proposed uses for the project are consistent with Employment
District (E).
Figure 1: Aerial Photograph
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Per the Centre for Advanced Technology 10th & 16th Filing Final Drainage and Erosion Control
Study, the calculated detention volume is 1.51ac-ft which includes runoff from C.A.T 10th and the
adjacent Worthington Circle. The detention storage volume is currently divided between a small
detention pond and ponding in the adjacent parking lot through a series of area inlets. There is
an existing 15” storm sewer in the northeast corner of the project site with a manhole and
restrictor plate down-stream of the existing detention pond. The required release rate per the
previous drainage report is 1.91cfs (2-yr historic). Stormwater is conveyed to the north to the
storm network in Centre Avenue and is ultimately discharged into Spring Creek.
FLOODPLAIN
The subject property is not located in a FEMA or City of Fort Collins regulatory floodplain.
II. DRAINAGE BASINS AND SUB-BASINS
A. MAJOR BASIN DESCRIPTION
Worthington Self Storage is within the City of Fort Collins Spring Creek major drainage basin which is
centrally located in Fort Collins. The Spring Creek drainage basin extends from Horsetooth Reservoir
to the confluence with the Poudre River. It encompasses 9 square miles in central Fort Collins. The
basin is dominated by residential development, but also includes open space and areas of
commercial development.
Figure 2: Regulatory Floodplains
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B. SUB-BASIN DESCRIPTION
The outfall for the project site is Spring Creek via the existing 15” storm sewer at the corner of
Worthington Circle and the private access road. Per the C.A.T 16th Filing drainage report the
existing 15” storm sewer and restrictor plate were sized to convey the calculated 2-yr historic
flow (1.91cfs) and ultimately discharges to Spring Creek. The existing crown of Worthington Circle
is the existing spill way for the detention.
The existing site can be defined with three (3) sub-basins. These include the drainage from the
Centre for Advanced Technology (C.A.T) 10th Filing, Worthington Circle public ROW and the
project site, C.A.T 16th Filing.
The site does receive notable surface runoff from adjacent properties and is detained and
released per the Centre for Advanced Technology 16th Filing Final Drainage and Erosion Control
Study. Flows from C.A.T 10th Filing, and Worthington Circle will be conveyed through the
proposed site and existing detention volumes will be maintained with this project. An existing
detention volume of 1.51acft was calculated per the C.A.T 16th Filing report which is currently
divided between an existing detention pond and ponding in the adjacent parking lot. Existing
detention methods will be modified from the current design, but storage volumes and release
rate will be maintained.
There is no increase in impervious area with the proposed project and historic versus proposed
impervious areas are documented within Appendix C. Existing detention volumes will be
maintained, but with the modification in impervious area LID and water quality treatment will be
included with the drainage design. Water quality will also be designed to include Lot 2 of the
project site to allow for future development of the rest of the property without additional
stormwater facilities.
III. DRAINAGE DESIGN CRITERIA
A. OPTIONAL REVISIONS
There are no optional provisions outside of the Fort Collins Stormwater Manual (FCSM) and the Mile
High Flood District (MHFD).
B. STORMWATER MANAGEMENT STRATEGY
The overall stormwater management strategy employed with Worthington Self Storage utilizes the
“Four Step Process” to minimize adverse impacts of urbanization on receiving waters. The following
is a description of how the proposed development has incorporated each step.
Step 1 – Employ Runoff Reduction Practices. The first consideration taken in trying to reduce the
stormwater impacts of this development is the site selection itself. By choosing an already
developed site with public storm sewer currently in place, the burden is significantly less than
developing a vacant parcel absent of any infrastructure.
Worthington Self Storage aims to reduce runoff peaks, volumes and pollutant loads from frequently
occurring storm events (i.e., water quality (i.e., 80th percentile) and 2-year storm events) by
implementing Low Impact Development (LID) strategies. Wherever practical, runoff will be routed
across landscaped areas or through underground chambers. These LID practices reduce the overall
amount of impervious area, while at the same time Minimizing Directly Connected Impervious Areas
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(MDCIA). The combined LID/MDCIA techniques will be implemented, where practical, throughout the
development, thereby slowing runoff and increasing opportunities for infiltration.
Step 2 – Implement BMPs that Provide a Water Quality Capture Volume (WQCV) with Slow
Release. The efforts taken in Step 1 will help to minimize excess runoff from frequently occurring
storm events; however, urban development of this intensity will still have stormwater runoff leaving
the site. The primary water quality treatment will occur in underground chambers and extended
detention pond.
Step 3 – Stabilize Drainageways. As stated in Section II.A, above, the site discharges into Spring
Creek, however no changes to the channel are proposed with this project. While this step may not
seem applicable to Worthington Self Storage, the proposed project indirectly helps achieve
stabilized drainageways, nonetheless. Once again, site selection has a positive effect on stream
stabilization. By developing with existing stormwater infrastructure, combined with LID and MDCIA
strategies, the likelihood of bed and bank erosion is reduced. Furthermore, this project will pay one-
time stormwater development fees, as well as ongoing monthly stormwater utility fees, both of
which help achieve Citywide drainageway stability.
Step 4 – Implement Site Specific and Other Source Control BMPs. This step typically applies to
industrial and commercial developments.
C. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS
The subject property is part of a Master Drainage Plan for The Centre for Advanced Technology
development. An Overall Development Plan (ODP) drainage study is also submitted concurrently
with this project. However, stormwater from Worthington Self Storage will generally follow
historic patterns and discharge into conveyance structures established as part of the Centre for
Advanced Technology 16th Filing.
The subject property is an “in-fill” development project as the property is surrounded by
currently developed properties and private access roads.
The existing 15-inch storm drain will function as the ultimate outfall for the project site.
D. HYDROLOGICAL CRITERIA
The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted in Figure 3.4-1
of the FCSCM, serve as the source for all hydrologic computations associated with Worthington
Self Storage development. Tabulated data contained in Table 3.4-1 has been utilized for Rational
Method runoff calculations.
The Rational Method has been employed to compute stormwater runoff utilizing coefficients
contained in Tables 3.2-1, 3.2-2, and 3.2-3 of the FCSCM.
The Rational Method will be used to estimate peak developed stormwater runoff from drainage
basins within the developed site for the 2-year, 10-year, and 100-year design storms. Peak runoff
discharges determined using this methodology have been used to check the street capacities,
inlets, swales, and storm drain lines.
Two separate design storms have been utilized to address distinct drainage scenarios. The first
event analyzed is the “Minor” or “Initial” Storm with a 2-year recurrence interval. The second
event considered is the “Major Storm” with a 100-year recurrence interval.
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E. HYDRAULIC CRITERIA
The hydraulic analyses of street capacities, inlets, storm drain lines, culverts, and swales will be
per the FCSM criteria and provided during Final Plan. The following computer programs and
methods will be utilized:
· The storm drain lines will be analyzed using the Hydraflow Express Extension for AutoCAD
Civil 3D.
· The inlets will be analyzed using the Urban Drainage Inlet and proprietary area inlet
spreadsheets.
· Swales and street capacities will be analyzed using the Urban Drainage Channels
spreadsheets.
F. FLOODPLAIN REGULATIONS COMPLIANCE
As previously mentioned, this project is not subject to any floodplain regulations.
G. MODIFICATIONS OF CRITERIA
No formal modifications are requested at this time.
H. CONFORMANCE WITH WATER QUALITY TREATMENT CRITERIA
City Code requires that 100% of runoff from a project site receive some sort of water quality
treatment. This project proposes to provide the majority of water quality treatment with
underground chambers. The chambers, when constructed per Fort Collins regulations, are
considered an LID treatment method. Due to the physical constraints associated with a project and
flows from adjacent properties there is a small area that cannot be captured with the underground
chambers. Treatment of this area will be provided with extended detention within the proposed
detention pond.
I. CONFORMANCE WITH LOW IMPACT DEVELOPMENT (LID)
The project site will conform with the requirement to treat a minimum of 75% of the project site
using a LID technique. LID treatment will be provided by underground chambers. Please see
Appendix C for LID design information, table, and exhibit(s). As shown in the LID table provided in
the appendix, Lot 1 will treat 83% of the proposed site impervious area, which exceeds the minimum
required. LID treatment will be provided for 100% of Lot 2, to allow for future development of the
rest of the site without additional drainage facilities.
IV. DRAINAGE FACILITY DESIGN
A. GENERAL CONCEPT
The main objective of Worthington Storage drainage design is to maintain existing drainage
patterns, while not adversely impacting adjacent properties.
There is off-site flows into the existing property that will be accounted for in the basins described
below.
A list of tables and figures used within this report can be found in the Table of Contents at the
front of the document. The tables and figures are located within the sections to which the
content best applies.
Drainage for the project site has been analyzed using six (6) drainage sub-basins. The drainage
patterns anticipated for the basins are further described below.
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Basin A1
Basin A1 is approximately 0.51 acres and consists of the two detention ponds, surrounding
landscaping areas and a portion of the parking lot in the northeast corner of the site. The
basin will generally maintain historic drainage patterns. Runoff from this basin will flow
into the onsite detention pond and backup into the proposed underground chambers for
additional storage. Offsite flow from C.A.T 10th Filing is conveyed in a concrete pan from
the north and collected in a proposed curb inlet. The detention ponds will provide both
detention for the surrounding basins and water quality in the form of extended (40-hour)
detention for just this basin. The detention pond will discharge into the existing 15-inch
storm drain outfall.
Basin A2
Basin A2 is approximately 1.43 acres and consists of the proposed buildings with the
Worthington Self Storage project. Runoff from this basin will sheet flow to valley pans in
the center of the proposed private access roads. Flow will be collected by area inlets and
discharge into underground chambers. Roof drain connections will also be made to the
proposed underground chambers. A water quality weir will be installed, and water quality
treatment will be provided for 100% of basin A2. Detention will be provided by a
combination of underground chambers and detention ponds.
Basin A3
Basin A3 is approximately 1.22 acres and consists of the existing cinema saver building
and adjacent parking lot. The basin will generally maintain historic drainage patterns.
Runoff will sheet flow and collect in gutters and valley pans, which will be collected by
area inlets on the proposed lot line. Water quality will be provided by underground
chambers. 100% of the basin will be treated so future development will not require future
stormwater facilities. Detention will be provided by a combination of underground
chambers and detention ponds.
Basin OS1
Basin OS1 is approximately 2.04 acres. This basin consists of the existing Centre for
Advanced Technology 10th filing development. The basin will maintain historic drainage
patterns from northwest to southeast. Runoff from this basin will sheet flow from the
existing structures and parking lots and collect in an existing concrete pan which will tie
into Basin A1 and discharge into a proposed curb inlet. Detention will be provided for this
basin in the proposed detention ponds and underground chambers.
Basin OS2
Basin OS2 is approximately 1.57 acres and consists of the existing residential buildings
along Shields St and a portion of a private access road along the west side of the site. The
basin will generally maintain historic drainage patterns from the southwest to the
northeast. Runoff from this basin will sheet flow and collect in a proposed area inlet
between basins A2 and A3. Detention will be provided for basin in the proposed
underground chambers and detention ponds. chambers.
Basin OS3
Basin OS3 is approximately 0.7 acres and consists of Worthington Circle. The basin will
generally maintain historic drainage patterns. Runoff from this basin will collect in the
existing curb and gutter and discharge into two existing inlets at the north corner of the
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project site. These inlets tie into the proposed detention pond. Detention will be provided
for this basin in the proposed detention pond and underground chambers.
A full-size copy of the Drainage Exhibit can be found in the Map Pocket at the end of this
report.
B. SPECIFIC DETAILS
The Worthington Self Storage project will be utilizing a combination of two detention ponds and
142 MC-3500 Stormtech chambers to fullfill their stormwater detention and treatment
requirements. Worthington Self Storage will be providing 100% WQCV using LID measures and
extended detention.
Detention Summary
Required Water Quality Volume (Pond) 0.01 ac-ft
Required Water Quality Volume (Chambers) 1.09 ac-ft
Required Detention Volume 1.51 ac-ft
Design Volume 1.62 ac-ft
Existing Release Rate 1.91 cfs
Table 1: Detention Pond Summary
MC-3500 Chamber Counts
Detention WQCV Total
120 22 142
Table 2: Chamber Count Summary
Final design details, detailed hydraulic calculations, and construction documentation, will be
provided to the City of Fort Collins for review prior to Final Development Plan approval.
V. CONCLUSIONS
A. COMPLIANCE WITH STANDARDS
The proposed drainage design for the Worthington Self Storage complies with the City of Fort
Collins Stormwater Criteria Manual.
The drainage design proposed with this project will maintain the existing detention volume and
release rate. The design will provide 100% WQVC using LID measures. Off-site flows will be
maintained through the project site.
The drainage plan and stormwater measurements proposed with Worthington Self Storage are
compliant with all applicable State and Fedaral regulations.
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VI. REFERENCES
1. City of Fort Collins Landscape Design Guidelines for Stormwater and Detention Facilities, November
5, 2009, BHA Design, Inc. with City of Fort Collins Utility Services.
2. Final Drainage and Erosion Control Study for Cinema Savers Centre for Advanced Technology
Sixteenth Filing., RBD, Inc., Fort Collins, Colorado, March 22, 1994.
3. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No.
159, 2018, and referenced in Section 26-500 of the City of Fort Collins Municipal Code.
4. Soils Resource Report for Larimer County Area, Colorado, Natural Resources Conservation Service,
United States Department of Agriculture.
5. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control District,
Wright-McLaughlin Engineers, Denver, Colorado, Revised April 2008.
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FORT COLLINS | GREELEY APPENDIX
APPENDIX A
HYDROLOGIC COMPUTATIONS
Runoff Coefficient1
Percent
Impervious1 Project:
Location:
0.95 100%Calc. By:
0.95 90%Date:
0.85 90%
0.55 50%
0.20 2%
0.20 2%
Basin ID Basin Area
(sq.ft.)
Basin Area
(acres)Asphalt (sq. ft.) Concrete (Sq. Ft.)
Asphalt, Concrete
(sq.ft.)
Asphalt, Concrete
(acres)Rooftop (sq.ft.) Rooftop (acres)
Lawns, Clayey Soil,
Flat Slope < 2%
(sq.ft.)
Lawns, Clayey Soil,
Flat Slope < 2%
(acres)
Percent
Impervious
C2*Cf
Cf = 1.00
C5*Cf
Cf = 1.00
C10*Cf
Cf = 1.00
C100*Cf
Cf = 1.25
A1 23,896 0.55 7880.000 1282.000 9162.000 0.21 964.00 0.02 13,770.00 0.32 43% 0.52 0.52 0.52 0.65
A2 62,173 1.43 21142.000 328.000 21470.000 0.49 32,798.00 0.75 7,905.00 0.18 82% 0.85 0.85 0.85 1.00
A3 52,954 1.22 21010.000 6882.000 27892.000 0.64 19,220.00 0.44 5,842.00 0.13 86% 0.87 0.87 0.87 1.00
OS1 88,927 2.04 44308.000 0.000 44308.000 1.02 11,700.00 0.27 32,919.00 0.76 62% 0.67 0.67 0.67 0.84
OS2 68,407 1.57 18320.000 0.000 18320.000 0.42 6,460.00 0.15 43,627.00 1.00 37% 0.47 0.47 0.47 0.59
OS3 30,483 0.70 24567.000 0.000 24567.000 0.56 0.00 0.00 5,916.00 0.14 81% 0.80 0.80 0.80 1.00
DEVELOPED RUNOFF COEFFICIENT CALCULATIONS
Asphalt, Concrete
Rooftop
Residential: High Density
Residential: Low Density
Streets, Parking Lots, Roofs, Alleys, and Drives:
Character of Surface:Worthington Storage
Fort Collins
M. Ruebel
February 23, 2022
Offsite Basins
Lawns and Landscaping:
2) Composite Runoff Coefficient adjusted per Table 3.2-3 of the Fort Collins
Stormwater Manual (FCSM).
Lawns, Clayey Soil, Flat Slope < 2%
USDA SOIL TYPE: C
Undeveloped: Greenbelts, Agriculture Composite Runoff Coefficient2
1) Runoff coefficients per Tables 3.2-1 & 3.2 of the FCSM. Percent impervious per Tables 4.1-2 & 4.1-3 of the FCSM.
Where:
n = Roughness Coefficient
R = Hydraulic Radius (feet)
S = Longitudinal Slope, feet/feet
Length
(ft)
Slope
(%)
Ti
2-Yr
(min)
Ti
10-Yr
(min)
Ti
100-Yr
(min)
Length
(ft)
Slope
(%)Surface n
Flow
Area3
(sq.ft.)
WP3 (ft)R (ft)V
(ft/s)
Tt
(min)
Max.
Tc
(min)
Comp.
Tc 2-Yr
(min)
Tc
2-Yr
(min)
Comp.
Tc 10-Yr
(min)
Tc
10-Yr
(min)
Comp.
Tc 100-
Yr
(min)
Tc
100-Yr
(min)
a1 A1 20 2.00%3.86 3.86 3.01 50
3.00%Gutter 0.02 3.61 19.18 0.19 5.65 0.15 10.39 4.01 5.00 4.01 5.00 3.15 5.00
a2 A2 100 2.00%3.64 3.64 1.48 200
0.50%Valley Pan 0.02 6.00 10.25 0.59 4.92 0.68 11.67 4.32 5.00 4.32 5.00 2.16 5.00
a3 A3 120 2.00%3.78 3.78 1.63 167
1.30%Valley Pan 0.02 6.00 10.25 0.59 7.93 0.35 11.59 4.14 5.00 4.14 5.00 1.98 5.00
os1 OS1 160 2.00%8.03 8.03 4.87 190 1.00% Valley Pan 0.02 6.00 10.25 0.59 6.95 0.46 11.94 8.48 8.48 8.48 8.48 5.33 5.33
os2 OS2 150 1.33%13.07 13.07 10.62 190 3.79% Gutter 0.02 3.61 19.18 0.19 6.35 0.50 11.89 13.57 11.89 13.57 11.89 11.12 11.12
os3 OS3 20 2.00%1.96 1.96 0.66 340 1.00% Gutter 0.02 3.61 19.18 0.19 3.26 1.74 12.00 3.70 5.00 3.70 5.00 2.40 5.00
NotesV = Velocity (ft/sec) WP = Wetted Perimeter (ft)
DEVELOPED TIME OF CONCENTRATION COMPUTATIONS
Location:
Maximum Tc:Overland Flow, Time of Concentration:
Channelized Flow, Velocity:Channelized Flow, Time of Concentration:
Worthington Storage
Fort Collins
M. Ruebel
February 23, 2022
Project:
Calculations By:
Date:
Offsite Basins
Design
Point Basin ID
Overland Flow Channelized Flow Time of Concentration
(Equation 3.3-2 per Fort Collins
Stormwater Manual)
=1.87 1.1 − ∗
=1.49 ∗
/∗(Equation 5-4 per Fort Collins)
=180 + 10
(Equation 3.3-5 per Fort Collins
Stormwater Manual)
=∗ 60
(Equation 5-5 per Fort Collins
1) Add 4900 to all elevations.
2) Per Fort Collins Stormwater Manual, minimum Tc = 5 min.
3) Assume a water depth of 6" and a typical curb and gutter per
Larimer County Urban Street Standard Detail 701 for curb and gutter
channelized flow. Assume a water depth of 1', fixed side slopes, and a
triangular swale section for grass channelized flow. Assume a water
depth of 1', 4:1 side slopes, and a 2' wide valley pan for channelized
flow in a valley pan.
Intensity, I from Fig. 3.4.1 Fort Collins Stormwater ManualRational Equation: Q = CiA (Equation 6-1 per MHFD)Tc2Tc10Tc100C2C10C100I2I10I100Q2Q10Q100a1A10.555.05.05.00.50.50.62.94.910.00.81.43.5a2A21.435.05.05.00.90.91.02.94.910.03.55.914.2a3A31.225.05.05.00.90.91.02.94.910.03.05.112.1os1 OS1 2.048.5 8.5 5.3 0.7 0.70.82.4 4.1 10.0 3.3 5.6 17.1os2 OS2 1.5711.9 11.9 11.1 0.5 0.50.62.1 3.6 7.4 1.5 2.6 6.9os3 OS3 0.705.0 5.0 5.0 0.8 0.81.02.9 4.9 10.0 1.6 2.7 7.0Offsite BasinsDate:Fort CollinsProject:Location:Calc. By:DEVELOPED DIRECT RUNOFF COMPUTATIONSIntensity (in/hr)Flow (cfs)Worthington StorageM. RuebelFebruary 22, 2022DesignPointBasinArea(acres)Runoff CTc (Min)
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FORT COLLINS | GREELEY APPENDIX
APPENDIX B
HYDRAULIC COMPUTATIONS
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FORT COLLINS | GREELEY APPENDIX
Additional hydraulic calculations will be provided during final design.
NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
APPENDIX C
DETENTION POND & WATER QUALITY
COMPUTATIONS
Pond ID
Required
Detention
Volume (cf)
Required
Water Quality
Volume (cf)
Required
Total Volume
(cf)
Design
Detention
Volume (cf)
Design Water
Quality
Volume (cf)
Design Total
Volume (cf)
Detention Pond 1 33803 450 34253 33,803 450 34253
Detention Pond 2 9303 0 9303 9303 0 9303
Stormtech Chambers 1 22669 3271 25940 23,227 3850 27077
Total 65775 3721 69496 66333 4300 70633
Detention WQCV Total
120 22 142
DETENTION & WATER QUALITY SUMMARY
MC-3500 Chamber Count
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FORT COLLINS | GREELEY APPENDIX
DETENTION FACILITIES
Project:Calc. By:
Location:Date:
Surface
Area (SF)% Imperv.Imperv.
Area (SF)
Surface
Area (SF)% Imperv.Imperv.
Area (SF)
Rooftop 19,220 100%19,220 Rooftop 52,983 100%52,983
Concrete 7,179 100%7,179 Concrete 8,738 100%8,738
Asphalt 86,223 100%86,223 Asphalt 49,667 100%49,667
Gravel 0 40%0 Gravel 0 40%0
Landscaping 27,023 0%0 Landscaping 28,257 0%0
Total 139,645 112,622 Total 139,645 111,388
-1,234
Existing Proposed
Additional Impervious Area (SF)
Onsite Impervious Areas
Worthington Storage M. Ruebel
Fort Collins, Colorado 02/23/22
Total Onsite Impervious Area
SSSCVAULTELECSSSELECCELECEDDDTCONTROLIRRGXXVAULTF.O.XXXXSSSCVAULTELECSSSELECCELECEDDDTCONTROLIRRGXXVAULTF.O.DRAWN BY:SCALE:DATE:EXISTING VS PROPOSEDIMPERVIOUS AREASHEET NO:FORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631ENGINEERNGIEHTRONRN970.221.4158northernengineering.comP:\1853-001\DWG\DRNG\1853-001_IMPV.DWG
2525 WORTHINGTON MINI-STORAGEFORT COLLINSCOLORADOMCREXISTINGPROPOSED( IN FEET )01 INCH = 60 FEET6060ROOFTOPCONCRETEASPHALTSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)19,2207,17986,223100%100%100%112,622TOTAL=19,2207,17986,223GRAVEL040%01" = 60'2/23/2022IMP 1LANDSCAPING27,0230%0ROOFTOPCONCRETEASPHALTSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)52,9838,73849,667100%100%100%111,388TOTAL=52,9838,73849,667GRAVEL040%0LANDSCAPING28,2570%0WO
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Project:
Date:
Pond No.:
4,945.20 0.78 ac. ft.
Spillway Elev.:4,952.00 5,052.00
5,053.00
1.00 ft.
Max. Elev. Min. Elev. cu. ft. acre ft cu. ft. acre ft
5,045.20 N/A 40.24 0.00 0.00 0.00 0.00 0.00
5,045.40 5,045.20 999.73 0.20 199.95 0.00 199.95 0.00
5,045.60 5,045.40 2,991.66 0.20 399.14 0.01 599.08 0.01
5,045.80 5,045.60 4,419.70 0.20 741.14 0.02 1,340.22 0.03
5,046.00 5,045.80 4,862.28 0.20 928.20 0.02 2,268.42 0.05
5,046.20 5,046.00 4,946.27 0.20 980.85 0.02 3,249.27 0.07
5,046.40 5,046.20 4,971.01 0.20 991.73 0.02 4,241.00 0.10
5,046.60 5,046.40 4,995.31 0.20 996.63 0.02 5,237.63 0.12
5,046.80 5,046.60 5,019.16 0.20 1,001.45 0.02 6,239.08 0.14
5,047.00 5,046.80 5,042.57 0.20 1,006.17 0.02 7,245.25 0.17
5,047.20 5,047.00 5,065.54 0.20 1,010.81 0.02 8,256.06 0.19
5,047.40 5,047.20 5,088.07 0.20 1,015.36 0.02 9,271.43 0.21
5,047.60 5,047.40 5,110.17 0.20 1,019.82 0.02 10,291.25 0.24
5,047.80 5,047.60 5,131.84 0.20 1,024.20 0.02 11,315.45 0.26
5,048.00 5,047.80 5,153.11 0.20 1,028.49 0.02 12,343.95 0.28
5,048.20 5,048.00 5,174.04 0.20 1,032.71 0.02 13,376.66 0.31
5,048.40 5,048.20 5,194.63 0.20 1,036.87 0.02 14,413.53 0.33
5,048.60 5,048.40 5,214.86 0.20 1,040.95 0.02 15,454.48 0.35
5,048.80 5,048.60 5,234.81 0.20 1,044.97 0.02 16,499.44 0.38
5,049.00 5,048.80 5,254.48 0.20 1,048.93 0.02 17,548.37 0.40
5,049.20 5,049.00 5,273.89 0.20 1,052.84 0.02 18,601.21 0.43
5,049.40 5,049.20 5,293.05 0.20 1,056.69 0.02 19,657.90 0.45
5,049.60 5,049.40 5,311.96 0.20 1,060.50 0.02 20,718.40 0.48
5,049.80 5,049.60 5,330.67 0.20 1,064.26 0.02 21,782.67 0.50
5,050.00 5,049.80 5,349.19 0.20 1,067.99 0.02 22,850.65 0.52
5,050.20 5,050.00 5,367.54 0.20 1,071.67 0.02 23,922.33 0.55
5,050.40 5,050.20 5,385.79 0.20 1,075.33 0.02 24,997.66 0.57
5,050.60 5,050.40 5,403.96 0.20 1,078.97 0.02 26,076.63 0.60
5,050.80 5,050.60 5,422.20 0.20 1,082.62 0.02 27,159.25 0.62
5,051.00 5,050.80 5,440.54 0.20 1,086.27 0.02 28,245.52 0.65
5,051.20 5,051.00 5,459.28 0.20 1,089.98 0.03 29,335.51 0.67
5,051.40 5,051.20 5,478.54 0.20 1,093.78 0.03 30,429.29 0.70
5,051.60 5,051.40 5,549.35 0.20 1,102.79 0.03 31,532.08 0.72
5,051.80 5,051.60 5,675.60 0.20 1,122.49 0.03 32,654.57 0.75
5,052.00 5,051.80 5,813.54 0.20 1,148.91 0.03 33,803.49 0.78
STAGE STORAGE CURVE
Contour Contour
Surface Area
(ft2)
Depth (ft)
Incremental Volume Cummalitive Volume
Pond Stage Storage Curve
1853-001
Fort Collins, Colorado
M. Ruebel
Elev at Design Volume:
Worthington Storage
February 23, 2022
Pond Outlet and Volume Data
Freeboard:
Crest of Pond Elev.:
Detention Pond
Project Number:
Project Location:
Calculations By:
Outlet Elevation:Design Volume:
Detention Pond 1
1
Project:
Date:
Pond No.:
5,046.00 0.21 ac. ft.
Spillway Elev.:5,052.00 5,052.00
5,053.00
1.00 ft.
Max. Elev. Min. Elev. cu. ft. acre ft cu. ft. acre ft
5,046.00 N/A 360.51 0.00 0.00 0.00 0.00 0.00
5,046.20 5,046.00 1,188.59 0.20 237.72 0.01 237.72 0.01
5,046.40 5,046.20 1,374.90 0.20 256.35 0.01 494.07 0.01
5,046.60 5,046.40 1,389.88 0.20 276.48 0.01 770.54 0.02
5,046.80 5,046.60 1,404.79 0.20 279.47 0.01 1,050.01 0.02
5,047.00 5,046.80 1,419.63 0.20 282.44 0.01 1,332.45 0.03
5,047.20 5,047.00 1,434.40 0.20 285.40 0.01 1,617.86 0.04
5,047.40 5,047.20 1,449.11 0.20 288.35 0.01 1,906.21 0.04
5,047.60 5,047.40 1,463.63 0.20 291.27 0.01 2,197.48 0.05
5,047.80 5,047.60 1,477.83 0.20 294.15 0.01 2,491.63 0.06
5,048.00 5,047.80 1,492.10 0.20 296.99 0.01 2,788.62 0.06
5,048.20 5,048.00 1,506.33 0.20 299.84 0.01 3,088.46 0.07
5,048.40 5,048.20 1,520.24 0.20 302.66 0.01 3,391.12 0.08
5,048.60 5,048.40 1,534.24 0.20 305.45 0.01 3,696.57 0.08
5,048.80 5,048.60 1,548.21 0.20 308.24 0.01 4,004.81 0.09
5,049.00 5,048.80 1,561.84 0.20 311.00 0.01 4,315.82 0.10
5,049.20 5,049.00 1,575.46 0.20 313.73 0.01 4,629.55 0.11
5,049.40 5,049.20 1,589.17 0.20 316.46 0.01 4,946.01 0.11
5,049.60 5,049.40 1,602.54 0.20 319.17 0.01 5,265.18 0.12
5,049.80 5,049.60 1,615.85 0.20 321.84 0.01 5,587.02 0.13
5,050.00 5,049.80 1,629.24 0.20 324.51 0.01 5,911.53 0.14
5,050.20 5,050.00 1,642.49 0.20 327.17 0.01 6,238.70 0.14
5,050.40 5,050.20 1,655.67 0.20 329.82 0.01 6,568.52 0.15
5,050.60 5,050.40 1,668.97 0.20 332.46 0.01 6,900.98 0.16
5,050.80 5,050.60 1,682.21 0.20 335.12 0.01 7,236.10 0.17
5,051.00 5,050.80 1,695.42 0.20 337.76 0.01 7,573.86 0.17
5,051.20 5,051.00 1,708.81 0.20 340.42 0.01 7,914.29 0.18
5,051.40 5,051.20 1,722.29 0.20 343.11 0.01 8,257.40 0.19
5,051.60 5,051.40 1,735.93 0.20 345.82 0.01 8,603.22 0.20
5,051.80 5,051.60 1,749.92 0.20 348.58 0.01 8,951.80 0.21
5,052.00 5,051.80 1,764.39 0.20 351.43 0.01 9,303.24 0.21
STAGE STORAGE CURVE
Contour Contour
Surface Area
(ft2)
Depth (ft)
Incremental Volume Cummalitive Volume
Pond Stage Storage Curve
1853-001
Fort Collins, Colorado
M. Ruebel
Elev at Design Volume:
Worthington Storage
February 23, 2022
Pond Outlet and Volume Data
Freeboard:
Crest of Pond Elev.:
Detention Pond
Project Number:
Project Location:
Calculations By:
Outlet Elevation:Design Volume:
Detention Pond 2
1
User Inputs
Chamber Model: MC-3500
Outlet Control Structure: Yes
Project Name: Red Rocks Self Stor-
age copy
Engineer: Mason undefined
Project Location: Colorado
Measurement Type: Imperial
Required Storage Volume: 23085 cubic ft.
Stone Porosity: 40%
Stone Foundation Depth: 9 in.
Stone Above Chambers: 12 in.
Average Cover Over Chambers: 18 in.
Design Constraint Dimensions:(500 ft. x 100 ft.)
Results
System Volume and Bed Size
Installed Storage Volume: 23227.56 cubic ft.
Storage Volume Per Chamber: 109.90 cubic ft.
Number Of Chambers Required: 120
Number Of End Caps Required: 20
Chamber Rows: 10
Maximum Length:103.40 ft.
Maximum Width: 71.27 ft.
Approx. Bed Size Required: 6879.98 square ft.
System Components
Amount Of Stone Required: 902.00 cubic yards
Volume Of Excavation (Not Including
Fill):
1401.48 cubic yards
Total Non-woven Geotextile Required:2101.36 square yards
Woven Geotextile Required (excluding
Isolator Row):
150.57 square yards
Woven Geotextile Required (Isolator
Row):
113.07 square yards
Total Woven Geotextile Required:263.64 square yards
NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
WATER QUALITY CALCULATIONS
Project:
Calc. By:
Date:
0.55 <-- INPUT from impervious calcs
43%<-- INPUT from impervious calcs
0.43 <-- CALCULATED
40 hours <-- from FCSM Figure 5.4-1
1.00 <-- from FCSM Figure 5.4-1
0.19 <-- MHFD Vol. 3 Equation 3-1
0.01 <-- FCSCM Equation 7-2
450 <-- Calculated from above
**<-- INPUT from stage-storage table
**<-- CALCULATED from Equation EDB-3
dia (in) =**
number of columns=**
number of rows =**
number of holes =**
Area Per Row =**
Total Outlet Area (in2) =**<-- CALCULATED from total number of holes
WQCV (watershed inches) =
WATER QUALITY POND DESIGN CALCULATIONS
Water Quality for Detention Pond
Worthington Storage
M. Ruebel
February 23, 2022
Required Storage & Outlet Works
Basin Area (acres) =
Basin Percent Imperviousness =
Basin Imperviousness Ratio =
Drain Time =
Drain Time Coefficient =
**To be completed at final design
WQCV (ac-ft) =
WQ Depth (ft) =
Area Required Per Row, a (in 2) =
Circular Perforation Sizing
WQCV (cu. ft.) =
NORTHERNENGINEERING.COM | 970.221.4158
FORT COLLINS | GREELEY
Project Title Date:
Project Number Calcs By:
City
Basins
0.8
WQCV = Watershed inches of Runoff (inches)82%
a = Runoff Volume Reduction (constant)
i = Total imperviousness Ratio (i = Iwq/100)0.273 in
A =1.43 ac
V = 0.0325 ac-ft
V = Water Quality Design Volume (ac-ft)
WQCV = Water Quality Capture Volume (inches)
A = Watershed Area (acres)
1700 cu. ft.
Drain Time
a =
i =
WQCV =
Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event
Worthington Storage February 22, 2022
1853-001 M. Ruebel
Fort Collins
Stormtech Chambers 1 (Lot 1)
0.231
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100)
Water Quality Capture Volume
6 hr
12 hr
24 hr
40 hr
()iii78.019.10.91aWQCV 23 +-=
()iii78.019.10.91aWQCV 23 +-=
AV*
12
WQCV
=
12 hr
Pond No :
A2,3,4, B1,2
WQ
1.00
5.00 min 1243 ft3
1.43 acres 0.03 ac-ft
Max Release Rate =0.45 cfs
Time (min)
Ft Collins
WQ
Intensity
(in/hr)
Inflow
Volume
(ft3)
Outflow
Adjustment
Factor
QWQ
(cfs)
Outflow Volume
(ft3)
Storage Volume
(ft3)
5 1.425 611 1.00 0.45 135 476
10 1.105 948 1.00 0.45 270 678
15 0.935 1203 0.67 0.30 270 933
20 0.805 1381 0.63 0.28 338 1044
25 0.715 1534 0.60 0.27 405 1129
30 0.650 1673 0.58 0.26 473 1201
35 0.585 1757 0.57 0.26 540 1217
40 0.535 1836 0.56 0.25 608 1229
45 0.495 1911 0.56 0.25 675 1236
50 0.460 1973 0.55 0.25 743 1231
55 0.435 2053 0.55 0.25 810 1243
60 0.410 2111 0.54 0.24 878 1233
65 0.385 2147 0.54 0.24 945 1202
70 0.365 2192 0.54 0.24 1013 1180
75 0.345 2220 0.53 0.24 1080 1140
80 0.330 2265 0.53 0.24 1148 1118
85 0.315 2297 0.53 0.24 1215 1082
90 0.305 2355 0.53 0.24 1283 1073
95 0.290 2364 0.53 0.24 1350 1014
100 0.280 2402 0.53 0.24 1418 985
105 0.270 2432 0.52 0.24 1485 947
110 0.260 2454 0.52 0.24 1553 901
115 0.255 2516 0.52 0.23 1620 896
120 0.245 2523 0.52 0.23 1688 835
*Note: Using the method described in FCSCM Chapter 6 Section 2.3
A =
Tc =
Project Location :
Design Point
C =
Design Storm
DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF
Input Variables Results
Required Detention Volume
Fort Collins, Colorado
1853-001
Worthington Storage
Project Number :
Project Name :
Stormtech Chambers 1 (Lot 1)
Page 2 of 5
1853-001 Chamber Summary_Lot 1
Vault IDTotal RequiredWQ Volume(cf)Flow,WQ(cfs)ChamberTypeChamber Release Ratea(cfs)ChamberVolumeb(cf)Installed Chamber w/ Aggregatec(cf)Mimimum No. of ChambersdTotal Release Ratee(cfs)Required Storage Volume by FAA Method(cf)Mimimum No. of ChambersfProvided Number of Chambers Provided Release Rate (cfs)Storage Provided within the Chambersg(cf)Total Installed System Volumeh(cf)Chamber 1 (Lot 1) 1700 1.97 MC-3500 0.038 109.90 175.00 10 0.38 124312 12 0.451319 2100a. Release rate per chamber, limited by flow through geotextile with accumulated sediment.b. Volume within chamber only, not accounting for void spaces in surrounding aggregate.c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit.d. Number of chambers required to provide full WQCV within total installed system, including aggregate.e. Release rate per chamber times number of chambers.f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage).g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume.h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV.Chamber Configuration SummaryP:\1853-001\Drainage\LID\1853-001 Chamber Summary_Lot 1
Project Title Date:
Project Number Calcs By:
City
Basins
0.8
WQCV = Watershed inches of Runoff (inches)86%
a = Runoff Volume Reduction (constant)
i = Total imperviousness Ratio (i = Iwq/100)0.296 in
A =1.22 ac
V = 0.0301 ac-ft
V = Water Quality Design Volume (ac-ft)
WQCV = Water Quality Capture Volume (inches)
A = Watershed Area (acres)
1571 cu. ft.
Drain Time
a =
i =
WQCV =
Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event
Worthington Storage February 22, 2022
1853-001 M. Ruebel
Fort Collins
Stormtech Chambers 1 (Lot 2)
0.231
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100)
Water Quality Capture Volume
6 hr
12 hr
24 hr
40 hr
()iii78.019.10.91aWQCV 23 +-=
()iii78.019.10.91aWQCV 23 +-=
AV*
12
WQCV
=
12 hr
Pond No :
A3
WQ
1.00
5.00 min 1067 ft3
1.22 acres 0.02 ac-ft
Max Release Rate =0.38 cfs
Time (min)
Ft Collins
WQ
Intensity
(in/hr)
Inflow
Volume
(ft3)
Outflow
Adjustment
Factor
QWQ
(cfs)
Outflow Volume
(ft3)
Storage Volume
(ft3)
5 1.425 522 1.00 0.38 114 408
10 1.105 809 1.00 0.38 228 581
15 0.935 1027 0.67 0.25 228 799
20 0.805 1179 0.63 0.24 285 894
25 0.715 1308 0.60 0.23 342 966
30 0.650 1427 0.58 0.22 399 1028
35 0.585 1499 0.57 0.22 456 1043
40 0.535 1566 0.56 0.21 513 1053
45 0.495 1631 0.56 0.21 570 1061
50 0.460 1684 0.55 0.21 627 1057
55 0.435 1751 0.55 0.21 684 1067
60 0.410 1801 0.54 0.21 741 1060
65 0.385 1832 0.54 0.20 798 1034
70 0.365 1870 0.54 0.20 855 1015
75 0.345 1894 0.53 0.20 912 982
80 0.330 1932 0.53 0.20 969 963
85 0.315 1960 0.53 0.20 1026 934
90 0.305 2009 0.53 0.20 1083 926
95 0.290 2017 0.53 0.20 1140 877
100 0.280 2050 0.53 0.20 1197 853
105 0.270 2075 0.52 0.20 1254 821
110 0.260 2094 0.52 0.20 1311 783
115 0.255 2147 0.52 0.20 1368 779
120 0.245 2152 0.52 0.20 1425 727
*Note: Using the method described in FCSCM Chapter 6 Section 2.3
A =
Tc =
Project Location :
Design Point
C =
Design Storm
DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF
Input Variables Results
Required Detention Volume
Fort Collins, Colorado
1853-001
Worthington Storage
Project Number :
Project Name :
Stormtech Chambers 1 (Lot 2)
Page 2 of 5
1853-001 Chamber Summary_Lot 2
Vault IDTotal RequiredWQ Volume(cf)Flow,WQ(cfs)ChamberTypeChamber Release Ratea(cfs)ChamberVolumeb(cf)Installed Chamber w/ Aggregatec(cf)Mimimum No. of ChambersdTotal Release Ratee(cfs)Required Storage Volume by FAA Method(cf)Mimimum No. of ChambersfProvided Number of Chambers Provided Release Rate (cfs)Storage Provided within the Chambersg(cf)Total Installed System Volumeh(cf)Chamber 1 (Lot 2) 1571 1.97 MC-3500 0.038 109.90 175.00 9 0.34 106710 10 0.381099 1750a. Release rate per chamber, limited by flow through geotextile with accumulated sediment.b. Volume within chamber only, not accounting for void spaces in surrounding aggregate.c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit.d. Number of chambers required to provide full WQCV within total installed system, including aggregate.e. Release rate per chamber times number of chambers.f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage).g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume.h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV.Chamber Configuration SummaryP:\1853-001\Drainage\LID\1853-001 Chamber Summary_Lot 2
Project Number:Project:
Project Location:
Calculations By:Date:
Sq. Ft. Acres
A1 (Lot 1)23,896 0.55 43%n/a n/a 0 10,275
A2 (Lot 1)62,173 1.43 82%Stormtech 1 Stormtech 3,271 50,982
A3 (Lot 2)52,954 1.22 86% Stormtech 1 Stormtech 3,271 45,540
Total 139,023 3.19 106,798
Project Number:Project:
Project Location:
Calculations By:Date:
Sq. Ft. Acres
Stormtech 1 (Lot 1) 62,173 1.43 82%
A2 Stormtech 1,417 1,700 50,982
Stormtech 1 (Lot 2) 52,954 1.22 86%
A3 Stormtech 1,309 1,571 45,540
Total 115,127 2.64 3,271 96,522
86,069 ft2
61,257 ft2
10,275 ft2
45,943 ft2
50,982 ft2
83.23%
139,023 ft2
106,798 ft2
10,275 ft2
96,522 ft2
90.38%
Total Treated Area*
Percent Impervious Treated by LID
*100% of Lot 2 is treated for water quailty for future development
LID Site Summary - Total Site
Total Area
Total Impervious Area
Total Impervious Area without LID Treatment
A1
LID Summary
AreaBasin ID Treatment TypePercent
Impervious LID ID
Worthington Storage
2/23/2022
1853-001
Fort Collins, Colorado
M. Ruebel
Total
Impervious
Area (ft2)
Required
Volume (ft3)
LID Summary per Basin
Area Weighted %
Impervious
1853-001 Worthington Storage
Fort Collins, Colorado
M.Ruebel 2/23/2022
LID Summary
LID Summary per LID Structure
Impervious
Area (ft2)
Vol. w/20%
Increase per
Fort Collins
Manual (ft3)
Subbasin ID Treatment TypeLID ID Volume per
UD-BMP (ft3)
Total Treated Area
Percent Impervious Treated by LID
A1
75% Requried Minium Area to be Treated for Lot 1
LID Site Summary - New Impervious Area Lot 1
Total Area Lot 1
Total Impervious Area Lot 1
Total Impervious Area without LID Treatment
UDUDUDUDUDUDUD UD UD UD UD UDUDUDUDUDUDUDXXXXCVAULTELECELECCELECEDDDTCONTROLIRRGXXVAULTF.O.a10.55 ac.A11.43 ac.A21.22 ac.A3a3a2DRAWN BY:SCALE:DATE:LID EXHIBITSHEET NO:FORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631ENGINEERNGIEHTRONRN970.221.4158northernengineering.comP:\1853-001\DWG\DRNG\1853-001_LID.DWG
WORTHINGTON ENCLOSED MINI-STORAGEFORT COLLINSCOLORADOMCR1" = 60'2/23/2022LID 1W
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PROPOSED STORM SEWERPROPOSED CURB & GUTTERPROPERTY BOUNDARYPROPOSED INLETADESIGN POINTDRAINAGE BASIN LABELDRAINAGE BASIN BOUNDARYALEGEND:FOR DRAINAGE REVIEW ONLYNOT FOR CONSTRUCTION( IN FEET )1 inch = ft.Feet0606060STORMTECH CHAMBERSPROPOSED INLETPROPOSED INLETPROPOSED CURB INLETPROPOSED INLETSTORMTECH CHAMBERS (ISOLATOR ROW)PROPOSED BASIN WITHWATER QUALITY WEIRLID Summary per LID StructureLID IDAreaWeighted %ImperviousSubbasin IDTreatment TypeVolume perUD-BMP (ft3)Vol. w/20%Increase per FortCollins Manual(ft3)ImperviousArea (ft2)Sq. Ft.AcresStormtech 1 (Lot 1)62,1731.4382%A2Stormtech1,4171,70050,982Stormtech 1 (Lot 2)52,9541.2286%A3Stormtech1,3091,57145,540Total115,1272.643,27196,522LID Site Summary - New Impervious Area Lot 1Total Area Lot 186,069ft2Total Impervious Area Lot 161,257ft2Total Impervious Area without LID Treatment10,275ft2A175% Requried Minium Area to be Treated for Lot 145,943ft2Total Treated Area50,982ft2Percent Impervious Treated by LID83.23%LOT 1LOT 2LID Site Summary - Total SiteTotal Area139,023ft2Total Impervious Area106,798ft2Total Impervious Area without LID Treatment10,275ft2A1Total Treated Area*96,522ft2Percent Impervious Treated by LID90.38%*100% of Lot 2 is treated for water quailty for future development
NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
APPENDIX D
EROSION CONTROL REPORT
NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY EROSION CONTROL REPORT
EROSION CONTROL REPORT
A comprehensive Erosion and Sediment Control Plan (along with associated details) has been included with the
final construction drawings. It should be noted; however, any such Erosion and Sediment Control Plan serves
only as a general guide to the Contractor. Staging and/or phasing of the BMPs depicted, and additional or
different BMPs from those included may be necessary during construction, or as required by the authorities
having jurisdiction.
It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained and
followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly adapting to
site conditions and needs. The Contractor shall update the location of BMPs as they are installed, removed, or
modified in conjunction with construction activities. It is imperative to appropriately reflect the current site
conditions at all times.
The Erosion and Sediment Control Plan shall address both temporary measures to be implemented during
construction, as well as permanent erosion control protection. Best Management Practices from the Volume 3,
Chapter 7 – Construction BMPs will be utilized. Measures may include, but are not limited to, silt fencing and/or
wattles along the disturbed perimeter, gutter protection in the adjacent roadways, and inlet protection at
existing and proposed storm inlets. Vehicle tracking control pads, spill containment and clean-up procedures,
designated concrete washout areas, dumpsters, and job site restrooms shall also be provided by the Contractor.
Grading and Erosion Control Notes can be found on Sheet CS2 of the Utility Plans. The Final Utility Plans will also
contain a full-size Erosion Control Plan as well as a separate sheet dedicated to Erosion Control Details. In
addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere to, the
applicable requirements outlined in any existing Development Agreement(s) of record, as well as the
Development Agreement, to be recorded prior to issuance of the Development Construction Permit. Also, the
Site Contractor for this project may be required to secure a Stormwater Construction General Permit from the
Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division – Stormwater
Program, before commencing any earth disturbing activities. Prior to securing said permit, the Site Contractor
shall develop a comprehensive Storm Water Management Plan (SWMP) pursuant to CDPHE requirements and
guidelines. The SWMP will further describe and document the ongoing activities, inspections, and maintenance
of construction BMPs.
NNORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
APPENDIX E
USDA SOILS REPORT
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
Larimer County
Area, Colorado
Worthington Storage
Natural
Resources
Conservation
Service
February 17, 2022
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
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
Contents
Preface....................................................................................................................2
How Soil Surveys Are Made..................................................................................5
Soil Map..................................................................................................................8
Soil Map................................................................................................................9
Legend................................................................................................................10
Map Unit Legend................................................................................................11
Map Unit Descriptions.........................................................................................11
Larimer County Area, Colorado......................................................................13
73—Nunn clay loam, 0 to 1 percent slopes.................................................13
74—Nunn clay loam, 1 to 3 percent slopes.................................................14
References............................................................................................................16
4
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
5
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
Custom Soil Resource Report
6
identified each as a specific map unit. Aerial photographs show trees, buildings,
fields, roads, and rivers, all of which help in locating boundaries accurately.
Custom Soil Resource Report
7
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.
8
9
Custom Soil Resource Report
Soil Map
4489180448920044892204489240448926044892804489300448932044893404489360448938044891804489200448922044892404489260448928044893004489320448934044893604489380491910 491930 491950 491970 491990 492010 492030 492050
491910 491930 491950 491970 491990 492010 492030 492050
40° 33' 18'' N 105° 5' 44'' W40° 33' 18'' N105° 5' 37'' W40° 33' 11'' N
105° 5' 44'' W40° 33' 11'' N
105° 5' 37'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 50 100 200 300
Feet
0 15 30 60 90
Meters
Map Scale: 1:1,070 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
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: Larimer County Area, Colorado
Survey Area Data: Version 16, Sep 2, 2021
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Aug 11, 2018—Aug
12, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
10
Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
73 Nunn clay loam, 0 to 1 percent
slopes
0.0 1.1%
74 Nunn clay loam, 1 to 3 percent
slopes
3.1 98.9%
Totals for Area of Interest 3.1 100.0%
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,
Custom Soil Resource Report
11
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.
Custom Soil Resource Report
12
Larimer County Area, Colorado
73—Nunn clay loam, 0 to 1 percent slopes
Map Unit Setting
National map unit symbol: 2tlng
Elevation: 4,100 to 5,700 feet
Mean annual precipitation: 14 to 15 inches
Mean annual air temperature: 48 to 52 degrees F
Frost-free period: 135 to 152 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Nunn and similar soils:85 percent
Minor components:15 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Nunn
Setting
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Parent material:Pleistocene aged alluvium and/or eolian deposits
Typical profile
Ap - 0 to 6 inches: clay loam
Bt1 - 6 to 10 inches: clay loam
Bt2 - 10 to 26 inches: clay loam
Btk - 26 to 31 inches: clay loam
Bk1 - 31 to 47 inches: loam
Bk2 - 47 to 80 inches: loam
Properties and qualities
Slope:0 to 1 percent
Depth to restrictive feature:More than 80 inches
Drainage class:Well drained
Runoff class: Medium
Capacity of the most limiting layer to transmit water (Ksat):Moderately low to
moderately high (0.06 to 0.20 in/hr)
Depth to water table:More than 80 inches
Frequency of flooding:None
Frequency of ponding:None
Calcium carbonate, maximum content:7 percent
Maximum salinity:Nonsaline (0.1 to 1.0 mmhos/cm)
Sodium adsorption ratio, maximum:0.5
Available water supply, 0 to 60 inches: High (about 9.1 inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: C
Ecological site: R067BY042CO - Clayey Plains
Hydric soil rating: No
Custom Soil Resource Report
13
Minor Components
Heldt
Percent of map unit:10 percent
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY042CO - Clayey Plains
Hydric soil rating: No
Wages
Percent of map unit:5 percent
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY002CO - Loamy Plains
Hydric soil rating: No
74—Nunn clay loam, 1 to 3 percent slopes
Map Unit Setting
National map unit symbol: 2tlpl
Elevation: 3,900 to 5,840 feet
Mean annual precipitation: 13 to 17 inches
Mean annual air temperature: 50 to 54 degrees F
Frost-free period: 135 to 160 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Nunn and similar soils:85 percent
Minor components:15 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Nunn
Setting
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Parent material:Pleistocene aged alluvium and/or eolian deposits
Typical profile
Ap - 0 to 9 inches: clay loam
Bt - 9 to 13 inches: clay loam
Btk - 13 to 25 inches: clay loam
Bk1 - 25 to 38 inches: clay loam
Bk2 - 38 to 80 inches: clay loam
Custom Soil Resource Report
14
Properties and qualities
Slope:1 to 3 percent
Depth to restrictive feature:More than 80 inches
Drainage class:Well drained
Runoff class: Medium
Capacity of the most limiting layer to transmit water (Ksat):Moderately low to
moderately high (0.06 to 0.20 in/hr)
Depth to water table:More than 80 inches
Frequency of flooding:None
Frequency of ponding:None
Calcium carbonate, maximum content:7 percent
Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm)
Sodium adsorption ratio, maximum:0.5
Available water supply, 0 to 60 inches: High (about 9.9 inches)
Interpretive groups
Land capability classification (irrigated): 2e
Land capability classification (nonirrigated): 3e
Hydrologic Soil Group: C
Ecological site: R067BY042CO - Clayey Plains
Hydric soil rating: No
Minor Components
Heldt
Percent of map unit:10 percent
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY042CO - Clayey Plains
Hydric soil rating: No
Satanta
Percent of map unit:5 percent
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY002CO - Loamy Plains
Hydric soil rating: No
Custom Soil Resource Report
15
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
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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.
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home/?cid=nrcs142p2_053374
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National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/
detail/national/landuse/rangepasture/?cid=stelprdb1043084
16
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
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cid=nrcs142p2_053624
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Custom Soil Resource Report
17
NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
APPENDIX F
EXCERPTS FROM CENTRE FOR ADVANCED TECHNOLOGY 16TH FILING
NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: TIMBER LARK RESIDENTIAL
FORT COLLINS | GREELEY APPENDIX
MAP POCKET
DR1 – DRAINAGE EXHIBIT
APPENDIX F
REFERENCE DOCUMENTS
STSTSTSTSTSTSTSTSTSTC
VAULT
ELEC
ELEC
C
ELEC
E
D
FE
SD
D
D
T
CONTROL
IRR
GXXX
TTTTTTVAULT
F.O.
OS2
OWNER: TALL DENTIST LLC
1001 CENTRE AVE
DODSANITY LLC
1013 CENTRE AVE
(EMPLOYMENT DISTRICT)
OWNER: KATSCH24 LLC
1007 CENTRE AVE
OWNER: AWEIDA PROPERTIES INC
2500 S SHIELDS ST
OWNER: AWEIDA
PROPERTIES INC
2514 S SHIELDS ST
OWNER: WARPAL LLC
1044 W DRAKE RD
MARKET CENTRE RETAIL
ASSOCIATION
OWNER: TWO PAULS LLC
932 W DRAKE RD
OWNER: ROBERT WILSON
2526 WORTHINGTON CIRCLE
OWNER: COLUMBINE MEDICAL
REAL ESTATE LLC
915 CENTRE AVE
CENTRE AVENUE
WO
R
T
H
I
NG
TO
N
C
I
R
C
L
E
S SHIELDS STREETP
R
I
V
A
T
E
A
C
C
E
S
S
R
O
A
DPRIVATE ACCESS ROADEXISTING
DETENTION
POND 1
PRIVA
T
E
A
C
C
E
S
S
R
O
A
D
EXISTING
BUILDING
2.27 ac.
H1
4.81 ac.
H2
0.43 ac.
H3
OS1
OS3
EXISTING 15" RCP
STORM DRAIN
EXISTING STORM MANHOLE
AND RESTRICTOR PLATE
SheetThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 17WORTHINGTON SELF STORAGEDR1 HISTORIC DRAINAGE EXHIBIT16
PROPOSED CONTOUR
PROPOSED STORM SEWER
PROPOSED SWALE
EXISTING CONTOUR
PROPOSED CURB & GUTTER
PROPERTY BOUNDARY
PROPOSED INLET
A
DESIGN POINT
FLOW ARROW
DRAINAGE BASIN LABEL
DRAINAGE BASIN BOUNDARY
PROPOSED SWALE SECTION
11
NOTES:
1.REFER TO THE PRELIMINARY DRAINAGE REPORT, DATED FEBRUARY 23, 2022 FOR
ADDITIONAL INFORMATION.
A
LEGEND:
FOR DRAINAGE REVIEW ONLY
NOT FOR CONSTRUCTION
NORTH
( IN FEET )
0
1 INCH = 40 FEET
40 40 80 120
STSTSTS
S
S
S
C
S
S
S
C
D
D
D
D
T
CONTROL
IRR
GXXX
TTTTTTVAULT
F.O.UDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUDUD
UD UDUDUDUDUD
XXXXXXX
Xa1
OWNER: TALL DENTIST LLC
1001 CENTRE AVE
DODSANITY LLC
1013 CENTRE AVE
(EMPLOYMENT DISTRICT)
OWNER: KATSCH24 LLC
1007 CENTRE AVE
OWNER: AWEIDA PROPERTIES INC
2500 S SHIELDS ST
OWNER: AWEIDA
PROPERTIES INC
2514 S SHIELDS ST
OWNER: WARPAL LLC
1044 W DRAKE RD
MARKET CENTRE RETAIL
ASSOCIATION
OWNER: TWO PAULS LLC
932 W DRAKE RD
OWNER: ROBERT WILSON
2526 WORTHINGTON CIRCLE
OWNER: COLUMBINE MEDICAL
REAL ESTATE LLC
915 CENTRE AVE
CENTRE AVENUE
WO
R
T
H
I
NG
TO
N
C
I
R
C
L
E
S SHIELDS STREETP
R
I
V
A
T
E
A
C
C
E
S
S
R
O
A
DPRIVATE ACCESS ROADDETENTION
POND 1
DETENTION
POND 2
PRIVA
T
E
A
C
C
E
S
S
R
O
A
D
EXISTING
BUILDING
PROPOSED
BUILDING
2.04 ac.
OS1
1.57 ac.
OS2
0.51 ac.
A1
1.43 ac.
A2
1.22 ac.
A3
0.70 ac.
OS3
os3
os1
os2
a3
a2
PROPOSED
GARAGE
EXISTING 15" RCP
STORM DRAIN
EXISTING STORM MANHOLE
AND RESTRICTOR PLATE
PROPOSED AREA INLET
PROPOSED CURB INLET
PROPOSED STORM
DRAIN
PROPOSED AREA INLET
PROPOSED BASIN WITH
WATER QUALITY WEIR
PROPOSED AREA INLET
SheetThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 17WORTHINGTON SELF STORAGEDR2 DRAINAGE EXHIBIT17
PROPOSED CONTOUR
PROPOSED STORM SEWER
PROPOSED SWALE
EXISTING CONTOUR
PROPOSED CURB & GUTTER
PROPERTY BOUNDARY
PROPOSED INLET
A
DESIGN POINT
FLOW ARROW
DRAINAGE BASIN LABEL
DRAINAGE BASIN BOUNDARY
PROPOSED SWALE SECTION
11
NOTES:
1.REFER TO THE PRELIMINARY DRAINAGE REPORT, DATED FEBRUARY 23, 2022 FOR
ADDITIONAL INFORMATION.
A
LEGEND:
FOR DRAINAGE REVIEW ONLY
NOT FOR CONSTRUCTION
NORTH
( IN FEET )
0
1 INCH = 40 FEET
40 40 80 120