HomeMy WebLinkAboutBUCKING HORSE PARK - BDR210011 - DOCUMENT MARKUPS - ROUND 3 - DRAINAGE REPORT
January 26, 2022
DRAINAGE AND EROSION CONTROL REPORT FOR
Bucking Horse Park
Fort Collins, Colorado
Prepared for:
City of Fort Collins
Attn: Matt Schaefer
PO Box 580
Fort Collins, Colorado 80522
Prepared by:
200 South College Avenue, Suite 10
Fort Collins, Colorado 80524
Phone: 970.221.4158 Fax: 970.221.4159
www.northernengineering.com
Project Number: 1748-002
This Drainage Report is consciously provided as a PDF.
Please consider the environment before printing this document in its entirety.
When a hard copy is necessary, we recommend double-sided printing.
January 26, 2022
City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
RE: Drainage and Erosion Control Report for
Bucking Horse Park
Dear Staff:
Northern Engineering is pleased to submit this Drainage and Erosion Control Report for your review.
This report accompanies the Basic Development Review (BDR) submittal for the proposed Bucking
Horse Park development.
This report was prepared in accordance with Fort Collins Stormwater Criteria Manual (FCSCM) and
serves to document the stormwater impacts associated with the proposed project. We understand
that review by the city is to assure general compliance with standardized criteria contained in the
FCSCM.
If you should have any questions as you review this report, please feel free to contact us.
Sincerely,
Northern Engineering Services, Inc.
Carlos Ortiz García Shane Ritchie, PE
Project Engineer Project Manager
Bucking Horse Park
Final Drainage Report
TABLE OF CONTENTS
I. GENERAL LOCATION AND DESCRIPTION ............................................................... 1
A. Location ............................................................................................................................................. 1
B. Description of Property ..................................................................................................................... 2
C. Floodplain.......................................................................................................................................... 3
II. DRAINAGE BASIN AND SUB-BASIN ........................................................................ 5
A. Major Basin Description .................................................................................................................... 5
B. Sub-Basin Description ....................................................................................................................... 5
III. DRAINAGE DESIGN CRITERIA ................................................................................. 5
A. Regulations........................................................................................................................................ 5
B. Hydrological Criteria ......................................................................................................................... 5
C. Hydraulic Criteria .............................................................................................................................. 5
D. Modifications of Criteria ................................................................................................................... 6
IV. DRAINAGE FACILITY DESIGN ................................................................................. 6
A. General Concept ............................................................................................................................... 6
B. Specific Details .................................................................................................................................. 7
C. LID Summary ..................................................................................................................................... 8
V. CONCLUSIONS ....................................................................................................... 8
A. Compliance with Standards .............................................................................................................. 8
VI. REFERENCES .......................................................................................................... 9
VII. EROSION CONTROL REPORT ................................................................................ 15
APPENDICES
APPENDIX A – Hydrologic Computations
APPENDIX B– Updated SWMM Model for Bucking Horse Second Filing
APPENDIX C– Hydraulic Computations
APPENDIX D– LID Sizing
APPENDIX E– Erosion Control Report and USDA Soils Report
LIST OF FIGURES
Figure 1 – Aerial Photograph ................................................................................................ 2
Figure 2 – Proposed Site Plan ............................................................................................... 3
Figure 3 – Area Floodplain Mapping ...................................................................................... 4
MAP POCKET
Proposed Drainage Exhibit
Bucking Horse Park
Bucking Horse Park Drainage Report 1
I. GENERAL LOCATION AND DESCRIPTION
Vicinity Map
A. LOCATION
1. Bucking Horse Park is located in the Southeast ¼ of Section 20, Township 7 North,
Range 68 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer,
State of Colorado. It is generally bound to the northwest by single family homes, the
east\northeast by the Great Western Railroad, the southwest by Miles Horse Avenue,
and the southeast by a daycare facility and Detention Pond 215.
2. An existing channel runs along the east boundary of the site parallel to the railroad right-
of-way, conveying stormwater from the surrounding area to Detention Pond 215.
3. Aside from the large channel that borders the site, offsite flows through the project area
are minimal. Refer to the Drainage Exhibit for offsite basin locations.
Bucking Horse Park
Bucking Horse Park Drainage Report 2
B. DESCRIPTION OF PROPERTY
1. The project area is roughly 7.54± acres.
Figure 1 – Aerial Photograph
2. The subject property is an undeveloped parcel with native ground cover. The existing
ground generally slopes at moderate grades (1%–3%) from the southwest to the
northeast, towards the channel that borders the east side of the site. There is a soil
stockpile located on the southeast corner of the site.
3. A soils report (Project No. FC09343-125) was completed by CTL Thompson, Inc. on
May 8, 2020. The report contains the results of a complete geotechnical subsurface
exploration as well as pertinent geotechnical recommendations.
4. The proposed project site plan is composed of one small restroom building, numerous
park amenities, and open spaces. Please see Figure 2, on the following page, showing
the proposed site plan.
Bucking Horse Park
Bucking Horse Park Drainage Report 3
Figure 2 – Proposed Site Plan
C. FLOODPLAIN
1. The Bucking Horse Park is currently located within a FEMA Moderate Risk Flood Hazard
Area for the Cache la Poudre River. This area is designated as Zone X on Firm Panel
0992G, Revised May 2, 2012. Therefore, it falls outside of the regulated 100-year
floodway and floodplain fringe. (Figure 3 – Area Floodplain Mapping)
Bucking Horse Park
Bucking Horse Park Drainage Report 4
Figure 3 – Existing Floodplain Mapping
It should be noted an updated floodplain map is being prepared by consultants for the
Colorado Water Conservation Board (CWCB) in coordination with the Federal Emergency
Management Agency (FEMA). This remapping is called RiskMAP. The updated mapping
will entirely remove the project site from any floodplain designations. Therefore, the
project site is not required to conform with the provisions of Chapter 10.
Figure 4 – Updated RiskMAP Floodplain Mapping
Bucking Horse Park
Bucking Horse Park Drainage Report 5
II. DRAINAGE BASIN AND SUB-BASIN
A. MAJOR BASIN DESCRIPTION
The Bucking Hose – Park is in Basin 57 of the Foothills Drainage Basin. According to the
updated Foothills Master Drainage Plan by Anderson Consulting Engineers (ACE) dated July
15, 1999, the project site was limited to a 100-year developed discharge of 85 CFS, which
equated to the 2-year historical rate.
B. SUB-BASIN DESCRIPTION
The subject property is located within the Bucking Horse Filing Two development and has
historically drained overland from southwest to northeast.
All of Bucking Horse Filing Two drains to Detention Pond 215. This pond currently provides
approximately 32.4 ac-ft of storage volume. The pond also provides water quality as a 40-
hour dry extended detention basin (EDB).
The project area was modeled as part of the SWMM model for Bucking Horse Filing Two.
This model has been updated to reflect the constructed conditions within the study area and
to document the final required detention volume for Pond 215 and the peak flow for the
channel running along the east boundary of the site. (See Appendix B)
A description of the project drainage patterns follows in Section IV.A. below.
III. DRAINAGE DESIGN CRITERIA
A. REGULATIONS
There are no optional provisions outside of the FCSCM with the proposed project.
B. HYDROLOGICAL CRITERIA
1. The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted in
Figure RA-16 of the FCSCM, serve as the source for all hydrologic computations
associated with the proposed development. Tabulated data contained in Table RA-7 was
utilized for Rational Method runoff calculations.
2. The Rational Method was employed to compute localized stormwater runoff utilizing
coefficients contained in Tables RO-11 and RO-12 of the FCSCM.
3. The previously approved SWMM model that was approved with Bucking Horse Filing
Two and updated as part of Bucking Horse Filing Four (Bucking Horse Apartments) has
been updated using current City criteria.
4. Two separate design storms were utilized to address distinct drainage scenarios. The
first event analyzed is the “Minor” or “Initial” Storm, which has a two-year recurrence
interval. The second event considered is the “Major” Storm, which has a 100-year
recurrence interval.
5. No other assumptions or calculation methods were used with this development that are
not referenced by the current City of Fort Collins criteria.
C. HYDRAULIC CRITERIA
1. As previously noted, the subject property maintains historical drainage patterns.
2. All drainage facilities proposed with the project are designed in accordance with the
criteria outlined in the FCSCM and/or Mile High Flood District (UDFCD) Urban Storm
Drainage Criteria Manual.
Bucking Horse Park
Bucking Horse Park Drainage Report 6
3. As previously mentioned, this project is not subject to any floodplain regulations.
D. MODIFICATIONS OF CRITERIA
No modifications are requested at this time.
IV. DRAINAGE FACILITY DESIGN
A. GENERAL CONCEPT
1. The main objectives of the project drainage design are to maintain existing drainage
patterns and ensure no adverse impacts to any adjacent properties.
2. There is no onsite detention and water quality treatment for this site since this has been
provided in Detention Pond 215.
3. The site was broken into seventeen (17) onsite basins and two (2) offsite basins for
design purposes. Anticipated drainage patterns for proposed drainage basins are
described below.
Basin 1
Basin 1 consists of sidewalks, gravel, and open areas. This basin will generally drain via
overland flow to a culvert pipe, routing flow to the existing swale running along the east
boundary of the site parallel to the Railroad, directing water out to Detention Pond 215.
Basins 6, 8, and 9
Basins 6, 8, and 9 consist of landscape areas. These basins will generally drain via
inlets and storm drains, routing flow to the existing swale running along the east
boundary of the site parallel to the Railroad, directing water out to Detention Pond 215.
Basins 5
Basins 5 consist primarily of open space. This basin will generally drain via overland to
inlets and storm drains, routing flow to the existing swale running along the east
boundary of the site parallel to the Railroad, directing water out to Detention Pond 215.
Basins 7, 10, and 11
Basins 7, 10, and 11 consist of sidewalks, gravel, landscape, and open areas. These
basins will generally drain via overland to inlets and storm drains, routing flow to the
existing swale running along the east boundary of the site parallel to the Railroad,
directing water out to Detention Pond 215.
Basin 12
Basin 12 consists of sidewalk, gravel, landscape, concrete, building, and open space
areas. This basin will generally drain via overland flow, routing flow to the existing swale
running along the east boundary of the site parallel to the Railroad, directing water out
to Detention Pond 215.
Basins 13, 14, and 15
Basins 13, 14, and 15 consist of sidewalk and open space areas. These basins will
generally drain via overland flow to Miles House Avenue routing flow along curb and
gutter to existing inlets.
Basin 16
Basins 16 consists of sidewalk and open space areas. These basins will drain via
overland flow along the southeast property boundary to Pond 215.
Bucking Horse Park
Bucking Horse Park Drainage Report 7
Basin OS1
Basin OS1 consists of open space from Bucking Horse Filing two residential lots. This
basin will generally drain via overland flow to Basin 1.
Basins OS2
Basin OS2, as shown on the Drainage Exhibit, consists of open space and sidewalk
along the northeast side of the existing swale running parallel to the Railroad.
B. SPECIFIC DETAILS
1. Large portions of the Bucking Horse neighborhood, including portions of Sidehill Filings
1 & 2 as well as Bucking Horse Filings 1, 2, 3 and 5 drain to Pond 215. Some drainage
from the west side of Timberline is also passed through the overall project area. Due to
the size of the drainage basin, a SWMM model was developed with the original filings to
document the overall drainage patterns in the study area.
2. The SWMM model was originally developed by JR Engineering as part of the Sidehill
development. It was subsequently updated with minor changes through the
development of the various filings that followed.
3. The most recent update was provided as part of Bucking Horse Filing 4 (aka – Bucking
Horse Apartments). In that iteration, all areas south of Nancy Gray were included in
Basin 107. While this delineation was appropriate for that project, it did not adequately
model the anticipated flows in the channel south of Nancy Gray.
4. In order to accurately model the channel flows adjacent to the Bucking Horse Park,
Basin 107 has been divided into 2 basins – Basin 107a and Basin 107b. This division
now provides accurate stormwater flows in the channel.
5. In addition to the updates to Basin 107, the impervious areas of the other SWMM
basins were updated to reflect the actual values, as opposed to using assumptions for
unknown projects. This was particularly true of Basin 105, where the percent
impervious was reduced from the originally assumed 75% to the actual 56%
documented as part of Bucking Horse Filing 4. The imperviousness of the park site has
also been updated to reflect the actual layout.
6. These updates to the SWMM model produce a required total Storage Volume of
870,255 c.f. (19.98 ac-ft), which is significantly less than what was originally called for
and far below the volume provided in Pond 215.
7. These updates to the SWMM model produce a calculated 100-yr flow in the channel of
341.1 cfs.
8. As a part of the planned City trail project that will be adjacent to Bucking Horse Park,
the trail is proposed to be relocated to the far side of the ditch, closer to the railroad
tracks. In order to accomplish this relocation, the ditch will be reconfigured from the
current symmetrical section to an asymmetrical section. This new channel configuration
has been modeled using the updated design flow x 1.33 to account for freeboard. The
results of this modeling are included in the appendices.
Bucking Horse Park
Bucking Horse Park Drainage Report 8
C. LID SUMMARY
1. The formal grass buffers located throughout the site will treat storm runoff for a
minimum of 50% of the modified or added impervious area on the site for water quality
prior to discharge into the public storm infrastructure, satisfying the City of Fort Collins
LID requirements. These features will facilitate sedimentation and filtration while
limiting erosion, providing both treatment and slowed release of the water quality
capture volume. The proposed redevelopment of this site will serve to limit water quality
and quantity impacts to natural drainageways by decreasing the frequency, rate,
duration, and volume of runoff.
2. An LID Exhibit highlighting where the formal grass buffers and contributing impervious
areas can be found in Appendix D.
3. The formal grass buffers were sized using Mile High Flood Control District criteria and
sizing spreadsheets. These calculations can also be found in Appendix D.
V. CONCLUSIONS
A. COMPLIANCE WITH STANDARDS
1. The drainage design proposed with the proposed project complies with the City of Fort
Collins’ Stormwater Criteria Manual, as well as previous drainage studies from which
downstream stormwater infrastructure was constructed
2. The drainage design proposed with this project complies with requirements for the
Foothills Basin.
3. The drainage plan and stormwater management measures proposed with the proposed
development are compliant with all applicable State and Federal regulations governing
stormwater discharge.
Bucking Horse Park
Bucking Horse Park Drainage Report 9
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. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by
Ordinance No. 174, 2011, and referenced in Section 26-500 (c) of the City of Fort
Collins Municipal Code.
3. Larimer County Urban Area Street Standards, Adopted January 2, 2001,
Repealed and Reenacted, Effective October 1, 2002, Repealed and Reenacted,
Effective April 1, 2007.
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, Mile High Flood Control
District, Denver, Colorado, Updated January 2016.
6. Geotechnical Investigation Proposed Improvements Bucking Horse Park, Fort
Collins, Colorado, May 8, 2020, CLT Thompson. (Project No. FC09343-125)
7. Final Drainage Report Bucking Horse Filing One, Dated September 19, 2012,
by Northern Engineering.
8. Final Drainage Report Bucking Horse Filing Two, Dated December 17, 2012, by
Northern Engineering
APPENDIX A
Hydrologic Computations
Where:
Length
(ft)
Elev
Up Elev Down Slope
(%)
Ti
2-Yr
(min)
Ti
10-Yr
(min)
Ti
100-Yr
(min)
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)Surface n
Flow
Area3
(sq.ft.)
WP3 (ft)R (ft)V
(ft/s)
Tt
(min)
Tc
2-Yr
(min)
Tc
100-Yr
(min)
1 (lid) 1 (LID)155 94.04 91.72 1.50%16.02 16.02 14.42 210 91.72 88.57 1.50% Swale (8:1)0.04 8.00 16.12 0.50 3.27 1.07 12.0 12.0
5 (lid) 5 (LID)56 94.12 92.83 2.29%9.16 9.16 8.52 48 92.83 91.96 1.81% Swale (8:1)0.04 8.00 16.12 0.50 3.59 0.22 9.4 8.7
6 6 18 93.96 93.60 2.00%5.67 5.67 5.35 31 93.60 92.97 2.01% Swale (8:1)0.04 8.00 16.12 0.50 3.79 0.14 5.8 5.5
7 7 131 96.42 92.79 2.77%10.52 10.52 8.96 185 92.79 90.11 1.45% Swale (8:1)0.04 8.00 16.12 0.50 3.21 0.96 11.5 9.9
8 8 18 93.96 93.60 2.03%5.59 5.59 5.28 21 93.60 93.18 1.99% Swale (8:1)0.04 8.00 16.12 0.50 3.77 0.09 5.7 5.4
9 9 18 93.97 93.60 2.01%5.72 5.72 5.40 32 93.60 92.96 2.00% Swale (8:1)0.04 8.00 16.12 0.50 3.78 0.14 5.9 5.5
10 10 86 98.90 92.40 7.56%7.53 7.53 6.98 146 92.40 90.11 1.57% Swale (8:1)0.04 8.00 16.12 0.50 3.34 0.73 8.3 7.7
11 11 92 98.92 92.33 7.15%7.66 7.66 7.02 134 92.33 90.11 1.66% Swale (8:1)0.04 8.00 16.12 0.50 3.44 0.65 8.3 7.7
12 (lid) 12 (LID)64 94.00 93.98 0.03%35.01 35.01 30.70 65 93.98 92.50 2.28% Swale (8:1)0.04 8.00 16.12 0.50 4.03 0.27 10.7 10.7
13 13 8 97.21 95.74 17.93%1.63 1.63 1.48 14 95.74 94.26 10.91% Swale (8:1)0.04 8.00 16.12 0.50 8.82 0.03 5.0 5.0
14 14 19 99.58 97.00 13.95%2.97 2.97 2.79 34 97.00 93.80 9.46% Swale (8:1)0.04 8.00 16.12 0.50 8.21 0.07 5.0 5.0
15 15 146 99.41 92.82 4.52%10.59 10.59 9.48 183 92.82 90.60 1.21% Swale (8:1)0.04 8.00 16.12 0.50 2.94 1.04 11.6 10.5
16 (lid) 16 (LID)79 94.29 92.60 2.14%10.86 10.86 10.04 111 92.60 88.85 3.39% Swale (8:1)0.04 8.00 16.12 0.50 4.91 0.38 11.1 10.4
os1 OS1 86 97.52 93.31 4.88%9.22 9.22 8.71 66 93.31 92.17 1.74% Swale (8:1)0.04 8.00 16.12 0.50 3.52 0.31 9.5 9.0
os2 OS2 25 90.77 86.75
15.98%3.02 3.02 2.75 599 86.75 84.18
0.43% Swale (8:1)0.04 8.00 16.12 0.50 1.75 5.71 8.7 8.5
1 to 12 + OS1 + OS2 155 94.04 91.72 1.50%17.32 17.32 16.06 210 91.72 88.57 1.50% Swale (8:1)0.04 8.00 16.12 0.50 3.27 1.07 12.0 12.0
1 + OS1 155 94.04 91.72 1.50%15.78 15.78 14.13 210 91.72 88.57 1.50% Swale (8:1)1.04 8.00 16.12 0.50 0.11 31.82 12.0 12.0
7, 10, & 11 (LID)86 98.90 92.40 7.56%6.85 6.85 6.13 146 92.40 90.11 1.57% Swale (8:1)0.04 8.00 16.12 0.50 2.93 0.83 7.7 7.0
Combined Basins
Design
Point Basin ID
Overland Flow Channelized Flow Time of
Developed Basins:
DEVELOPED TIME OF CONCENTRATION COMPUTATIONS
Maximum Tc:Overland Flow, Time of Concentration:
Channelized Flow, Velocity:Channelized Flow, Time of Concentration:
Bucking Horse Park
Fort Collins
C. Ortiz
January 24, 2022
Notes
S = Longitudinal Slope, feet/feet
R = Hydraulic Radius (feet)
n = Roughness Coefficient
V = Velocity (ft/sec)WP = Wetted Perimeter (ft)
(Equation 3.3-2 per Fort Collins Stormwater Manual)=1.87 1.1 − ∗
=1.49 ∗
/∗(Equation 5-4 per Fort Collins Stormwater Manual)
=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
Page 2 of 3
APPENDIX B
Updated SWMM Model for Bucking Horse Second Filing Computation
WDDXXXXDXDE DEDDD DDDDDD D D DLPDDDD R.T.U.R.T.U.R.T.U.UP
MILES HOUSE AVENUENANCY GRAY
AVENUE
PA
L
O
M
I
N
O
D
R
I
V
E
P
A
L
O
M
I
N
O
C
O
U
R
TWALKALOOSA WAYPALOMINO DRIVEWALKALOOSA WAYMILES HOUSE AVENUEDRAKE ROADGREAT WESTERN RAILROADTRACT BFUTURE CITY PARKTRACT EHORSEAREANANCY GRAYWETLANDTRACT ICOMMUNITYSUPPORTEDAGRICULTUREXXXXX420 SF
CLASSRO
O
M9
HALL11
1149 SFBARN12
6"
114 SFOFFICE15
115 SFOFFICE16
WOMENS17
MENS18
371 SF
TRACTOR / EQUIP.STORAGE19
COW MILKING20
MILKING PREP21
JAN.22MECH.23OFFICEBUILDING 1OFFICEBLDG 2OFFICEBLDG 3TRACT ATRACT FT
R
A
C
T
G TRACT HTRACT DOUTLOT AOUTLOT DOUTLOT FOUTLOT EOUTLOT GOUTLOT HOFFICECOMPLEXNATIVE UPLANDHABITAT AREA/DETENTION PONDTRACT CWORKINGFARM101102103105108109100107a107b104DRAWN BY: ATCSCALE: 1" = 500'ISSUED: 10/19/2021SWMM BASIN UPDATESHEET NO:1BUCKING HORSE SECOND FILING
Elapsed Time (hours)
6543210Volume (ft3)900000.0
800000.0
700000.0
600000.0
500000.0
400000.0
300000.0
200000.0
100000.0
0.0
Node 215 Volume (ft3)
SWMM 5 Page 1
Elapsed Time (hours)
6543210Flow (CFS)90.0
80.0
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
Link out215 Flow (CFS)
SWMM 5 Page 1
Elapsed Time (hours)
6543210Flow (CFS)350.0
300.0
250.0
200.0
150.0
100.0
50.0
0.0
Link IN_215a Flow (CFS)
SWMM 5 Page 1
EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.014)
--------------------------------------------------------------
WARNING 02: maximum depth increased for Node 302
WARNING 02: maximum depth increased for Node 303
WARNING 02: maximum depth increased for Node 304
WARNING 02: maximum depth increased for Node 305
WARNING 02: maximum depth increased for Node 306
WARNING 02: maximum depth increased for Node 307
*********************************************************
NOTE: The summary statistics displayed in this report are
based on results found at every computational time step,
not just on results from each reporting time step.
*********************************************************
****************
Analysis Options
****************
Flow Units ............... CFS
Process Models:
Rainfall/Runoff ........ YES
RDII ................... NO
Snowmelt ............... NO
Groundwater ............ NO
Flow Routing ........... YES
Ponding Allowed ........ NO
Water Quality .......... NO
Infiltration Method ...... HORTON
Flow Routing Method ...... KINWAVE
Starting Date ............ 11/21/2012 00:00:00
Ending Date .............. 11/21/2012 06:00:00
Antecedent Dry Days ...... 0.0
Report Time Step ......... 00:01:00
Wet Time Step ............ 00:05:00
Dry Time Step ............ 01:00:00
Routing Time Step ........ 30.00 sec
************************** Volume Depth
SWMM 5 Page 1
Runoff Quantity Continuity acre-feet inches
************************** --------- -------
Total Precipitation ...... 62.620 3.669
Evaporation Loss ......... 0.000 0.000
Infiltration Loss ........ 18.769 1.100
Surface Runoff ........... 43.386 2.542
Final Storage ............ 0.753 0.044
Continuity Error (%) ..... -0.458
************************** Volume Volume
Flow Routing Continuity acre-feet 10^6 gal
************************** --------- ---------
Dry Weather Inflow ....... 0.000 0.000
Wet Weather Inflow ....... 43.385 14.138
Groundwater Inflow ....... 0.000 0.000
RDII Inflow .............. 0.000 0.000
External Inflow .......... 0.000 0.000
External Outflow ......... 34.675 11.299
Flooding Loss ............ 1.442 0.470
Evaporation Loss ......... 0.000 0.000
Exfiltration Loss ........ 0.000 0.000
Initial Stored Volume .... 0.000 0.000
Final Stored Volume ...... 7.247 2.361
Continuity Error (%) ..... 0.050
********************************
Highest Flow Instability Indexes
********************************
Link out002 (36)
Link 202 (27)
Link 5 (23)
Link 204 (3)
Link 203 (2)
*************************
Routing Time Step Summary
*************************
Minimum Time Step : 30.00 sec
SWMM 5 Page 2
Average Time Step : 30.00 sec
Maximum Time Step : 30.00 sec
Percent in Steady State : 0.00
Average Iterations per Step : 1.27
Percent Not Converging : 0.00
***************************
Subcatchment Runoff Summary
***************************
------------------------------------------------------------------------------------------------------------------------------
Total Total Total Total Imperv Perv Total Total Peak Runoff
Precip Runon Evap Infil Runoff Runoff Runoff Runoff Runoff Coeff
Subcatchment in in in in in in in 10^6 gal CFS
------------------------------------------------------------------------------------------------------------------------------
109 3.67 0.00 0.00 0.68 1.98 0.97 2.95 1.15 101.36 0.805
108 3.67 0.00 0.00 0.68 1.98 0.97 2.95 1.74 153.81 0.805
100 3.67 0.00 0.00 0.42 2.52 0.69 3.20 1.04 105.75 0.873
102 3.67 0.00 0.00 0.68 1.94 1.03 2.96 2.61 245.74 0.808
101 3.67 0.00 0.00 1.33 1.76 0.51 2.28 0.97 39.41 0.621
104 3.67 0.00 0.00 0.65 1.99 1.00 2.99 0.78 75.55 0.816
105 3.67 0.00 0.00 0.64 2.01 0.98 2.99 1.71 161.94 0.816
106 3.67 0.00 0.00 2.68 0.04 0.95 0.99 0.00 0.04 0.270
107a 3.67 0.00 0.00 1.76 0.62 1.28 1.90 1.63 73.64 0.519
107b 3.67 0.00 0.00 1.66 0.83 1.16 1.99 2.52 127.09 0.542
******************
Node Depth Summary
******************
---------------------------------------------------------------------------------
Average Maximum Maximum Time of Max Reported
Depth Depth HGL Occurrence Max Depth
Node Type Feet Feet Feet days hr:min Feet
---------------------------------------------------------------------------------
302 JUNCTION 1.84 4.00 101.90 0 00:56 4.00
mh002 JUNCTION 0.51 2.29 102.59 0 00:49 2.29
mh001 JUNCTION 2.78 10.00 109.00 0 00:52 10.00
303 JUNCTION 1.05 1.84 97.74 0 00:40 1.83
SWMM 5 Page 3
304 JUNCTION 1.14 2.79 96.69 0 00:40 2.77
305 JUNCTION 1.23 3.03 95.93 0 00:41 3.03
306 JUNCTION 1.23 3.03 95.53 0 00:41 3.03
307 JUNCTION 0.59 1.49 93.49 0 00:41 1.49
OUTFALL OUTFALL 0.00 0.00 90.00 0 00:00 0.00
001 STORAGE 2.36 6.15 106.15 0 01:14 6.15
002 STORAGE 0.84 7.43 109.43 0 00:49 7.43
4 STORAGE 2.77 3.64 105.64 0 02:07 3.64
18 STORAGE 0.74 2.84 104.84 0 00:55 2.84
215 STORAGE 3.08 4.17 95.17 0 02:25 4.17
*******************
Node Inflow Summary
*******************
-------------------------------------------------------------------------------------------------
Maximum Maximum Lateral Total Flow
Lateral Total Time of Max Inflow Inflow Balance
Inflow Inflow Occurrence Volume Volume Error
Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent
-------------------------------------------------------------------------------------------------
302 JUNCTION 0.00 98.62 0 01:42 0 6.3 0.000
mh002 JUNCTION 0.00 109.39 0 00:49 0 2.61 0.000
mh001 JUNCTION 0.00 122.79 0 01:14 0 6.77 -0.000
303 JUNCTION 75.55 120.51 0 00:40 0.78 7.07 -0.000
304 JUNCTION 161.94 274.44 0 00:40 1.71 8.77 0.000
305 JUNCTION 0.04 270.30 0 00:41 0.00269 8.76 0.000
306 JUNCTION 73.64 340.99 0 00:41 1.63 10.4 0.000
307 JUNCTION 127.09 464.21 0 00:41 2.52 12.9 -0.000
OUTFALL OUTFALL 0.00 82.00 0 01:55 0 11.3 0.000
001 STORAGE 39.41 183.67 0 00:47 0.965 6.79 0.031
002 STORAGE 245.74 245.74 0 00:40 2.61 2.61 0.033
4 STORAGE 255.17 255.17 0 00:40 2.89 2.89 0.016
18 STORAGE 105.75 105.75 0 00:40 1.04 1.04 0.043
215 STORAGE 0.00 464.29 0 00:41 0 12.9 -0.000
*********************
Node Flooding Summary
*********************
SWMM 5 Page 4
Flooding refers to all water that overflows a node, whether it ponds or not.
--------------------------------------------------------------------------
Total Maximum
Maximum Time of Max Flood Ponded
Hours Rate Occurrence Volume Volume
Node Flooded CFS days hr:min 10^6 gal 1000 ft3
--------------------------------------------------------------------------
mh001 0.93 30.42 0 01:14 0.470 0.000
**********************
Storage Volume Summary
**********************
--------------------------------------------------------------------------------------------------
Average Avg Evap Exfil Maximum Max Time of Max Maximum
Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow
Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS
--------------------------------------------------------------------------------------------------
001 49.352 12 0 0 184.148 46 0 01:13 122.79
002 6.389 5 0 0 78.352 60 0 00:49 109.39
4 184.780 8 0 0 289.040 13 0 02:07 16.00
18 11.650 2 0 0 60.646 8 0 00:54 23.90
215 536.149 11 0 0 870.255 17 0 02:25 82.00
***********************
Outfall Loading Summary
***********************
-----------------------------------------------------------
Flow Avg Max Total
Freq Flow Flow Volume
Outfall Node Pcnt CFS CFS 10^6 gal
-----------------------------------------------------------
OUTFALL 97.08 72.08 82.00 11.298
-----------------------------------------------------------
System 97.08 72.08 82.00 11.298
SWMM 5 Page 5
********************
Link Flow Summary
********************
-----------------------------------------------------------------------------
Maximum Time of Max Maximum Max/ Max/
|Flow| Occurrence |Veloc| Full Full
Link Type CFS days hr:min ft/sec Flow Depth
-----------------------------------------------------------------------------
202 CONDUIT 109.39 0 00:49 9.98 0.23 0.33
201 CONDUIT 98.62 0 01:42 8.55 1.07 1.00
203 CONDUIT 97.93 0 00:56 7.71 0.01 0.08
204 CONDUIT 117.67 0 00:41 8.27 0.02 0.09
205 CONDUIT 270.26 0 00:41 10.26 0.04 0.14
206 CONDUIT 269.50 0 00:41 11.02 0.10 0.22
IN_215a CONDUIT 341.10 0 00:41 32.19 0.01 0.07
IN_215b CONDUIT 464.29 0 00:41 45.01 0.01 0.07
out002 DUMMY 109.39 0 00:49
out001 DUMMY 122.79 0 01:14
out4 DUMMY 16.00 0 00:50
5 DUMMY 23.90 0 00:55
out215 DUMMY 82.00 0 01:55
*************************
Conduit Surcharge Summary
*************************
----------------------------------------------------------------------------
Hours Hours
--------- Hours Full -------- Above Full Capacity
Conduit Both Ends Upstream Dnstream Normal Flow Limited
----------------------------------------------------------------------------
201 0.92 0.92 0.92 0.93 0.92
Analysis begun on: Wed Oct 20 08:52:10 2021
Analysis ended on: Wed Oct 20 08:52:10 2021
Total elapsed time: < 1 sec
SWMM 5 Page 6
This unofficial copy was downloaded on Oct-11-2021 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com
For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA
[TITLE]
;;Project Title/Notes
[OPTIONS]
;;Option Value
FLOW_UNITS CFS
INFILTRATION HORTON
FLOW_ROUTING KINWAVE
LINK_OFFSETS DEPTH
MIN_SLOPE 0
ALLOW_PONDING NO
SKIP_STEADY_STATE NO
START_DATE 11/21/2012
START_TIME 00:00:00
REPORT_START_DATE 11/21/2012
REPORT_START_TIME 00:00:00
END_DATE 11/21/2012
END_TIME 06:00:00
SWEEP_START 01/01
SWEEP_END 12/31
DRY_DAYS 0
REPORT_STEP 00:01:00
WET_STEP 00:05:00
DRY_STEP 01:00:00
ROUTING_STEP 0:00:30
RULE_STEP 00:00:00
INERTIAL_DAMPING PARTIAL
NORMAL_FLOW_LIMITED BOTH
FORCE_MAIN_EQUATION H-W
VARIABLE_STEP 0.75
LENGTHENING_STEP 0
MIN_SURFAREA 12.566
MAX_TRIALS 8
HEAD_TOLERANCE 0.005
SYS_FLOW_TOL 5
LAT_FLOW_TOL 5
MINIMUM_STEP 0.5
THREADS 1
[EVAPORATION]
;;Data Source Parameters
;;-------------- ----------------
CONSTANT 0.0
DRY_ONLY NO
[RAINGAGES]
;;Name Format Interval SCF Source
;;-------------- --------- ------ ------ ----------
FtCollins-100yr INTENSITY 0:05 1.0 TIMESERIES 100yr
[SUBCATCHMENTS]
;;Name Rain Gage Outlet Area %Imperv Width %Slope CurbLen SnowPack
;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- ----------------
109 FtCollins-100yr 4 14.3 55 2076 1 0
108 FtCollins-100yr 4 21.7 55 3150 1 0
100 FtCollins-100yr 18 12.0 70 1742 2.6 0
102 FtCollins-100yr 002 32.4 53.9 4705 2.2 0
101 FtCollins-100yr 001 15.6 49.8 2265 .004 0
104 FtCollins-100yr 303 9.6 55.4 1343 3 0
105 FtCollins-100yr 304 21.0 56 3049 2.1 0
106 FtCollins-100yr 305 .1 1 1 2.6 0
107a FtCollins-100yr 306 31.5 17.2 1087 1.5 0
107b FtCollins-100yr 307 46.6 23.0 1373 1.5 0
[SUBAREAS]
;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted
;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
109 .016 .25 .1 .3 0 OUTLET
108 .016 .25 .1 .3 0 OUTLET
100 .016 .25 .1 .3 0 OUTLET
102 .016 .25 .1 .3 0 OUTLET
101 .016 .25 .1 .3 0 OUTLET
104 .016 .25 .1 .3 0 OUTLET
105 .016 .25 .1 .3 0 OUTLET
106 .016 .25 .1 .3 0 OUTLET
107a .016 .25 .1 .3 0 OUTLET
107b .016 .25 .1 .3 0 OUTLET
[INFILTRATION]
;;Subcatchment MaxRate MinRate Decay DryTime MaxInfil
;;-------------- ---------- ---------- ---------- ---------- ----------
109 .51 0.5 6.48 7 0
108 .51 0.5 6.48 7 0
100 .51 0.5 6.48 7 0
102 .51 0.5 6.48 7 0
101 .51 0.5 6.48 7 0
104 .51 0.5 6.48 7 0
105 .51 0.5 6.48 7 0
106 .51 0.5 6.48 7 0
107a .51 0.5 6.48 7 0
107b .51 0.5 6.48 7 0
[JUNCTIONS]
;;Name Elevation MaxDepth InitDepth SurDepth Aponded
;;-------------- ---------- ---------- ---------- ---------- ----------
302 97.9 10 0 0 0
mh002 100.3 10 0 0 0
mh001 99 10 0 0 0
303 95.9 10 0 0 0
304 93.9 10 0 0 0
305 92.9 10 0 0 0
306 92.5 10 0 0 0
307 92.0 10 0 0 0
[OUTFALLS]
;;Name Elevation Type Stage Data Gated Route To
;;-------------- ---------- ---------- ---------------- -------- ----------------
OUTFALL 90 FREE NO
[STORAGE]
;;Name Elev. MaxDepth InitDepth Shape Curve Name/Params N/A Fevap Psi
Ksat IMD
;;-------------- -------- ---------- ----------- ---------- ---------------------------- -------- --------
-------- --------
001 100 10 0 TABULAR P1 0 0
002 102 10 0 TABULAR P2 0 0
4 102 10 0 TABULAR P4 0 0
18 102 10 0 TABULAR t 0 0
215 91 10 0 TABULAR P215 0 0
[CONDUITS]
;;Name From Node To Node Length Roughness InOffset OutOffset InitFlow MaxFlow
;;-------------- ---------------- ---------------- ---------- ---------- ---------- ---------- ---------- ----------
202 mh002 001 55 .013 0 0 0 0
201 mh001 302 266 .013 0 0 0 0
203 302 303 505 .013 0 0 0 0
204 303 304 482 .013 0 0 0 0
205 304 305 260 .013 0 0 0 0
206 305 306 95 .013 0 0 0 0
IN_215a 306 307 10 0.01 0 0 0 0
IN_215b 307 215 10 0.01 0 0 0 0
[OUTLETS]
;;Name From Node To Node Offset Type QTable/Qcoeff Qexpon Gated
;;-------------- ---------------- ---------------- ---------- --------------- ---------------- ---------- --------
out002 002 mh002 0 TABULAR/DEPTH O2 NO
out001 001 mh001 0 TABULAR/DEPTH O1 NO
out4 4 001 0 TABULAR/DEPTH O4 NO
5 18 001 0 TABULAR/DEPTH T_O NO
out215 215 OUTFALL 0 TABULAR/DEPTH O215 NO
[XSECTIONS]
;;Link Shape Geom1 Geom2 Geom3 Geom4 Barrels Culvert
;;-------------- ------------ ---------------- ---------- ---------- ---------- ---------- ----------
202 CIRCULAR 7 0 0 0 1
201 CIRCULAR 4 0 0 0 1
203 CIRCULAR 20 0 0 0 1
204 CIRCULAR 20 0 0 0 1
205 CIRCULAR 20 0 0 0 1
206 CIRCULAR 14 0 0 0 1
IN_215a CIRCULAR 20 0 0 0 1
IN_215b CIRCULAR 20 0 0 0 1
[CURVES]
;;Name Type X-Value Y-Value
;;-------------- ---------- ---------- ----------
det1 Rating 102 0
det1 104 30
det1 106 60
;
pond2 Rating 0 0
pond2 4 7
pond2 8 14
;
det2 Rating 0 0
det2 4 7
det2 8 14
;
p1out Rating 0 0.0
p1out 1 0.3
p1out 2 0.5
p1out 3 0.6
p1out 4 0.7
p1out 5 0.8
p1out 6 0.8
p1out 7.2 0.9
;
p2out Rating 0.00 0.00
p2out 0.20 4.00
p2out 1.20 8.34
p2out 2.20 8.59
p2out 3.20 8.83
p2out 4.20 9.06
p2out 5.20 9.29
p2out 6.00 9.47
;
out3 Rating 0.00 0.00
out3 1.10 6.00
out3 2.10 12.94
out3 3.10 18.90
out3 4.10 23.38
out3 5.10 27.14
out3 6.10 30.43
out3 6.70 33.40
;
outlet4 Rating 0 0
outlet4 2 1
outlet4 4 1.5
;
outle5 Rating 0 0
outle5 2 1
outle5 4 1.5
;
O4 Rating 0 0
O4 1 4
O4 2 10
O4 3 16
;
O3 Rating 0 0
O3 2.6 20
O3 4.6 40
O3 5.6 60
;
O1 Rating 0 0
O1 1.8 30
O1 3.8 60
O1 6.8 140
;
O2 Rating 0 0
O2 1.6 46.6
O2 3.6 72.10
O2 4.6 82.8
O2 5.6 92.3
O2 6.6 101.2
O2 7.6 111.1
;
T_O Rating 0 0
T_O 2 18
T_O 4 32
;
O215 Rating 0 0
O215 2 65
O215 4 82
;
pond1 Storage 0.00 186.71
pond1 1.00 11610.97
pond1 2.00 18910.48
pond1 3.00 27597.47
pond1 4.00 37457.72
pond1 5.00 42732.82
pond1 6.00 47703.39
pond1 7.20 53728.51
;
detpond2 Storage 0.00 422.47
detpond2 0.20 1667.16
detpond2 1.00 6743.86
detpond2 2.00 16049.38
detpond2 3.00 22104.10
detpond2 4.00 26630.53
detpond2 5.00 30414.38
detpond2 6.00 34190.32
;
pond3 Storage 0.00 0.00
pond3 1.10 7902.02
pond3 2.10 29813.22
pond3 3.10 64874.66
pond3 4.10 103295.75
pond3 5.10 112676.39
pond3 6.10 122158.92
pond3 6.70 127897.52
;
detpond4 Storage 0 0
detpond4 2 25000
detpond4 4 50000
;
detpond5 Storage 0 0
detpond5 2 20000
detpond5 4 50000
;
P4 Storage 0 0
P4 1 43560
P4 2 87120
P4 3 130680
;
P3 Storage 0 0
P3 2.6 12637
P3 4.6 16646
P3 5.6 18800
;
P1 Storage 0 0
P1 1.8 24042
P1 3.8 37538
P1 6.8 51067
;
P2 Storage 0 0
P2 1.6 7629
P2 3.6 10697
P2 4.6 12381
P2 5.6 14165
P2 6.6 16049
P2 7.6 18034
;
t Storage 0 0
t 2 30000
t 4 60000
;
P215 Storage 0 0
P215 2 200000
P215 4 400000
[TIMESERIES]
;;Name Date Time Value
;;-------------- ---------- ---------- ----------
100yr 0:05 1
100yr 0:10 1.14
100yr 0:15 1.33
100yr 0:20 2.23
100yr 0:25 2.84
100yr 0:30 5.49
100yr 0:35 9.95
100yr 0:40 4.12
100yr 0:45 2.48
100yr 0:50 1.46
100yr 0:55 1.22
100yr 1:00 1.06
100yr 1:05 1
100yr 1:10 0.95
100yr 1:15 0.91
100yr 1:20 0.87
100yr 1:25 0.84
100yr 1:30 0.81
100yr 1:35 0.78
100yr 1:40 0.75
100yr 1:45 0.73
100yr 1:50 0.71
100yr 1:55 0.69
100yr 2:00 0.67
[REPORT]
;;Reporting Options
SUBCATCHMENTS ALL
NODES ALL
LINKS ALL
[TAGS]
[MAP]
DIMENSIONS 0.000 0.000 10000.000 10000.000
Units None
[COORDINATES]
;;Node X-Coord Y-Coord
;;-------------- ------------------ ------------------
302 4359.410 7244.898
mh002 3520.408 7494.331
mh001 4359.410 7925.170
303 4393.733 6403.270
304 4475.477 5422.343
305 4543.597 4441.417
306 4598.093 3487.738
307 5242.215 3483.276
OUTFALL 6432.403 2650.215
001 4359.410 8492.063
002 2658.730 7494.331
4 3554.422 9387.755
18 3506.006 8483.483
215 6121.245 3487.124
[VERTICES]
;;Link X-Coord Y-Coord
;;-------------- ------------------ ------------------
[Polygons]
;;Subcatchment X-Coord Y-Coord
;;-------------- ------------------ ------------------
109 2783.447 9078.798
109 2783.447 9101.474
109 2772.109 9101.474
109 2794.785 9090.136
108 2866.591 9527.589
108 2741.875 9527.589
108 2775.888 9686.319
100 2859.033 8473.167
100 2722.978 8473.167
100 2802.343 8597.884
102 1986.017 7475.435
102 1838.624 7588.813
102 1838.624 7452.759
101 5273.998 8450.491
101 5160.620 8439.153
101 5160.620 8552.532
104 3428.771 6298.883
104 3400.838 6452.514
105 3417.382 5364.807
105 3353.004 5354.077
105 3363.734 5482.833
106 3385.193 4366.953
106 3310.086 4345.494
106 3310.086 4484.979
107a 3893.093 3008.413
107a 3828.715 2997.684
107a 3817.985 3094.250
107b 4638.601 2964.245
107b 4684.737 3033.449
107b 4534.794 3033.449
[SYMBOLS]
;;Gage X-Coord Y-Coord
;;-------------- ------------------ ------------------
FtCollins-100yr -582.579 8495.475
APPENDIX C
Hydraulic Computations
Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Oct 20 2021
Main Channel (341 cfs 100-yr flow x 1.33)
User-defined
Invert Elev (ft) = 4885.82
Slope (%) = 0.30
N-Value = 0.035
Calculations
Compute by: Known Q
Known Q (cfs) = 454.00
(Sta, El, n)-(Sta, El, n)...
( 0.00, 4890.43)-(15.00, 4889.87, 0.035)-(31.00, 4885.82, 0.035)-(44.00, 4886.08, 0.035)-(60.00, 4890.02, 0.035)
Highlighted
Depth (ft) = 3.95
Q (cfs) = 454.00
Area (sqft) = 108.13
Velocity (ft/s) = 4.20
Wetted Perim (ft) = 44.53
Crit Depth, Yc (ft) = 2.71
Top Width (ft) = 43.59
EGL (ft) = 4.22
-5 0 5 10 15 20 25 30 35 40 45 50 55 60 65
Elev (ft) Depth (ft)Section
4884.00 -1.82
4885.00 -0.82
4886.00 0.18
4887.00 1.18
4888.00 2.18
4889.00 3.18
4890.00 4.18
4891.00 5.18
Sta (ft)
Project Name:Bucking Horse Park Project Number :1748-002
Location :Fort Collins, CO.Computation By :COG
Design Point:Storm Drain Ap (FES-A1)Check By :SR
Given:Based on Urban Storm Drainage Criteria Manual
1.50 D Conduit Diameter (ft.) 18 (in)Volume 1, Major Drainage, June 2001
8.35 Q Discharge (cf/s)Reference for all Figures and Tables noted
5.90 V Velocity (f/s)
0.60 Yt Tail Water Depth (ft.) (For unknown Yt, Yt=D*0.4)
3.03 Q / D2.5 Froude Number
Determine Type of Riprap Protection (See Figure MD-21)
0.40 Yt / D
4.55 Q / D1.5
L Type of Riprap (Select Type VL, L, M, H, VH)
9 d50 (in.)Table MD-7
Percent smaller than Intermediate Rock
given size by weight dimension (in.)
70-100 15
50-70 12
35-50 9
2-10 3
Determine Expansion Factor (See Figure MD-22)
0.40 Yt / D
3.03 Q / D2.5
4.25 1/(2tan )
Determine Length of Riprap Protection
1.52 Q / V At = required area of flow at required velocity (ft.) (Required Velocity = 5.5 f/s, erosive soils)
4.38 Eq. MD-22 Lp = Required length of riprap (ft.)L = ( 1/(2tan ) )( At/Yt - D) )
4.50 L < 3D Check Minimum length
15.00 L < 10D Check Maximum length
4.50 Proposed Length (ft.)
Determine Width of Riprap Protection
4.50 Minimum Width (3*D)
2.25 SY Required
Determine Minimum Riprap Depth
2d50 =1.50 ft.
Determine Bedding Thickness
L Type of Riprap
6 Type II Bedding (in.)Table MD-12
RIPRAP EROSION PROTECTION AT CIRCULAR CONDUIT OUTLET
FIGURE MD-22
EXPANSION FACTOR FOR CIRCULAR CONDUITS
RIPRAP EROSION PROTECTION
Single Circular Conduit Outlet Protection
FIGURE MD-21
1748-002_RIPRAP_ Circular Conduit.xls, Storm Drain AP-100
Project Name:Bucking Horse Park Project Number :1748-002
Location :Fort Collins, CO.Computation By :COG
Design Point:Park Culvert (FES-P1)Check By :SR
Given:Based on Urban Storm Drainage Criteria Manual
1.00 D Conduit Diameter (ft.) 12 (in)Volume 1, Major Drainage, June 2001
1.38 Q Discharge (cf/s)Reference for all Figures and Tables noted
2.22 V Velocity (f/s)
0.40 Yt Tail Water Depth (ft.) (For unknown Yt, Yt=D*0.4)
1.38 Q / D2.5 Froude Number
Determine Type of Riprap Protection (See Figure MD-21)
0.40 Yt / D
1.38 Q / D1.5
L Type of Riprap (Select Type VL, L, M, H, VH)
9 d50 (in.)Table MD-7
Percent smaller than Intermediate Rock
given size by weight dimension (in.)
70-100 15
50-70 12
35-50 9
2-10 3
Determine Expansion Factor (See Figure MD-22)
0.40 Yt / D
1.38 Q / D2.5
6.50 1/(2tan )
Determine Length of Riprap Protection
0.25 Q / V At = required area of flow at required velocity (ft.) (Required Velocity = 5.5 f/s, erosive soils)
-2.42 Eq. MD-22 Lp = Required length of riprap (ft.)L = ( 1/(2tan ) )( At/Yt - D) )
3.00 L < 3D Check Minimum length
10.00 L < 10D Check Maximum length
3.00 Proposed Length (ft.)
Determine Width of Riprap Protection
3.00 Minimum Width (3*D)
1.00 SY Required
Determine Minimum Riprap Depth
2d50 =1.50 ft.
Determine Bedding Thickness
L Type of Riprap
6 Type II Bedding (in.)Table MD-12
FIGURE MD-21
RIPRAP EROSION PROTECTION AT CIRCULAR CONDUIT OUTLET
FIGURE MD-22
EXPANSION FACTOR FOR CIRCULAR CONDUITS
RIPRAP EROSION PROTECTION
Single Circular Conduit Outlet Protection
1748-002_RIPRAP_ Circular Conduit.xls, Park Culvert
APPENDIX D
LID SIZING
Sheet 1 of 1
Designer:
Company:
Date:
Project:
Location:
1. Design Discharge
A) 2-Year Peak Flow Rate of the Area Draining to the Grass Buffer Q2 =0.3 cfs
2.Minimum Width of Grass Buffer WG =6 ft
3.Length of Grass Buffer (14' or greater recommended)LG =341 ft
4.Buffer Slope (in the direction of flow, not to exceed 0.1 ft / ft)SG =0.080 ft / ft
5. Flow Characteristics (sheet or concentrated)
A) Does runoff flow into the grass buffer across the
entire width of the buffer?
B) Watershed Flow Length FL=45 ft
C) Interface Slope (normal to flow)SI=0.013 ft / ft
D) Type of Flow SHEET FLOW
Sheet Flow: FL * SI < 1
Concentrated Flow: FL * SI > 1
6. Flow Distribution for Concentrated Flows
7 Soil Preparation
(Describe soil amendment)
8 Vegetation (Check the type used or describe "Other")
9. Irrigation
(*Select None if existing buffer area has 80% vegetation
AND will not be disturbed during construction.)
10. Outflow Collection (Check the type used or describe "Other")
Notes:
Design Procedure Form: Grass Buffer (GB)
LID Basin 1
Northern Engineering
Bucking Horse Park
January 18, 2022
UD-BMP (Version 3.07, March 2018)
Fort Collins, CO
SEE SOIL AMENDMENT NOTES ON DRAINAGE PLAN
Existing Xeric Turf Grass
Irrigated Turf Grass
Other (Explain):
Choose One
Choose One
Grass Swale
Street Gutter
Storm Sewer Inlet
Other (Explain):
None (sheet flow)
Slotted Curbing
Level Spreader
Choose One
Other (Explain):
Choose One
Yes No
Choose One
Permanent
None*
Temporary
1
Basin ID LID Treatment
Impervious Area
(sq. ft.)
Impervious Area
Treated By LID (sq.
ft.)
Percent of
Impervious
Treated by LID
1 Grass Buffer 3,511 3,511 100%
5 Grass Buffer 1,913 1,913 100%
7, 10, & 11 Grass Buffer 17,521 17,521 100%
12 Grass Buffer 16,563 3,096 19%
16 Grass Buffer 3,155 3,155 100%
Total Site 45,450 29,195 64%
LID SUMMARY
X
6' GRASS
BUFFER (MIN.)
4' GRASS
BUFFER (MIN.)
32' GRASS
BUFFER (MIN.)
19' GRASS
BUFFER (MIN.)
11' GRASS
BUFFER (MIN.)MILES
HOUSE
AVE
.
STORM
DRAIN
(TYP.)
SWALE (TYP.)
LID EXHIBIT
GRASS BUFFER SUMMARY
FORT COLLINS, CO
BUCKING HORSE PARK
E N G I N E E R N GI
EHTRON R N
01.18.2022
P:\1748-002\DWG\DRNG\PARK\1748-002_PARK_LID.DWG
NORTH
FORMAL GRASS BUFFER AREA
PROPOSED CONTOUR
PROPOSED STORM SEWER
PROPOSED SWALE
EXISTING CONTOUR
PROPOSED CURB & GUTTER
BASIN 5
PROPOSED INLET
LEGEND:
PROPERTY BOUNDARY
BASIN 1
BASIN 7, 10, & 11
BASIN 12
BASIN 16
IMPERVIOUS AREA'S BEING TREATED BY GRASS BUFFER
BASIN 5
BASIN 1
BASIN 7, 10, & 11
BASIN 12
BASIN 16
Basin ID LID Treatment
Impervious Area
(sq. ft.)
Impervious Area
Treated By LID
(sq. ft.)
Percent of Impervious
Treated by LID
1 Grass Buffer 3511 3511 100%
5 Grass Buffer 1913 1913 100%
7, 10, & 11 Grass Buffer 17521 17521 100%
12 Grass Buffer 16563 3096 19%
16 Grass Buffer 3155 3155 100%
Total Site 45450 29195 64%
NOTES
1.FOR LID AND GRASS BUFFER CALCULATIONS PLEASE
REFER TO THE DRAINAGE AND EROSION CONTROL
REPORT FOR BUCKING HORSE PARK DATED JAN. 26 2022.
2.REFER TO UTILITY PLANS FOR BUCKING HORSE PARK
FOR ADDITIONAL GRADING AND UTILITY INFORMATION.
3.REFER TO LANDSCAPE PLANS FOR ADDITIONAL
INFORMATION ON HARDSCAPES.
4.REFER TO DRAINAGE EXHIBIT SHEET DR1 OF UTILITY
PLANS FOR SOIL AMENDMENT NOTES
( IN FEET )
0
1 INCH = 100 FEET
100 100
TFEXISTING
DETENTION
POND 215
1
OS1
5
6
7
8
9
10
11
12
14
15
16
13
S
S
S
S
S
S
S
S
S
SWWWWW CMWWSSSSSSSSSSSSSSSSS
S
SSS
S
SS
S
SEWWWWWXXXX
X
X
X
X
XX
X
XXXXX100' ROW
GREAT WESTERN
RAIL ROAD
CO
CO
CO
CO
CO
S
S
S
S
SSSSSSSSSSSSSCO
CO
CO
CO
COS
S
S
S
S
S
S
SSSSSSSHYD
EMILES
HOUSE
AVENUEPALOMINO COURT
15
0.38 ac
1
0.49 ac
6
0.06 ac
7
0.82 ac
8
0.03 ac
9
0.05 ac
10
0.40 ac
11
0.84 ac
12
1.20 ac
13
0.16 ac
14
0.39 ac
16
0.96 ac
OS1
0.65 ac
OS2
1.39 ac
OS2
5
0.35 ac
PROPERTY
BOUNDARY
POUDRE RIVER 500-YR
FLOODPLAIN (PER RiskMAP)
PROPERTY
BOUNDARY
PROPERTY
BOUNDARY
PROPERTY
BOUNDARY
PROPOSED
AREA DRAIN
PROPOSED
AREA DRAIN
PROPOSED
AREA DRAIN
PROPOSED
AREA DRAIN
PROPOSED
AREA DRAIN
PROPOSED
AREA DRAIN
RE-ALIGN EXISTING SWALE
DR1 DRAINAGE EXHIBIT14
NORTH
( IN FEET )
1 inch = ft.
Feet05050
50
100 150
SOIL AMENDMENT NOTES:
1.REFER TO THE DRAINAGE AND EROSION CONTROL REPORT FOR BUCKING HORSE
PARK DATED JAN. 26 2022 FOR ADDITIONAL INFORMATION.
2.THIS PROPERTY IS CURRENTLY LOCATED IN THE FEMA MODERATE RISK FLOOD
HAZARD AREA FOR THE CACHE LA POUDRE RIVER. BUT THE PROPOSED
REMAPPING FROM RISKMAP WILL REMOVE ALL FLOODPLAIN DESIGNATIONS FROM
THE PROJECT AREA.
3.REFER TO THE LANDSCAPE PLANS BY CITY OF FORT COLLINS FOR ADDITIONAL
LANDSCAPING INFORMATION.
LEGEND:
PROPOSED CONTOUR
PROPOSED STORM SEWER
PROPOSED SWALE
EXISTING CONTOUR
PROPOSED CURB & GUTTER
PROPERTY BOUNDARY
PROPOSED INLET
ADESIGN POINT
FLOW ARROW
DRAINAGE BASIN LABEL
DRAINAGE BASIN BOUNDARY
PROPOSED SWALE SECTION
11
CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU
DIG, GRADE, OR EXCAVATE FOR THE MARKING OF
UNDERGROUND MEMBER UTILITIES.
CALL UTILITY NOTIFICATION CENTER OF
COLORADO
Know what'sbelow.
before you dig.Call
R
SheetBUCKING HORSE PARKThese 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 14
10
0.37 ac
BASIN
DESIGNATION
BASIN
AREA (AC)
NOTES:
1.LOOSEN THE TOP 8 INCHES
2.TILL OR MIX 3 CUBIC YARDS OF AMENDMENT PER 1,000 SQUARE FEET INTO THE
TOP 6 INCHES OF SOIL OR
3.ADD 4 INCHES OF TOPSOIL THAT MEETS THE FOLLOWING REQUIREMENTS
TOPSOIL MUST BE FREE FROM NOXIOUS WEEDS, ROOTS, SALTS, CLAY LUMPS AND ANY
NON-SOIL MATERIALS (ROCKS, CONCRETE, BRICK CHIPS, BUILDING MATERIALS,
FOREIGN MATTER AND ANY CHEMICAL, BIOLOGICAL OR RADIOLOGICAL
CONTAMINANTS).
TOPSOIL REQUIREMENTS
SAND 20% - 75%
SILT 5% - 60%
CLAY 5% - 30%
ORGANIC MATERIAL 5% OR MORE
Ph 6.0 - 8.0
C2 C100 Q2
(cfs)
Q100
(cfs)