HomeMy WebLinkAboutBLOOM FILING FOUR - PDP230003 - SUBMITTAL DOCUMENTS - ROUND 2 - DRAINAGE REPORT
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Preliminary Drainage and Erosion Control
Report
Bloom Multi Family
Fort Collins, CO
Prepared for:
Hartford Acquisitions, LLC
4801 Goodman Road
Timnath, CO 80547
June 6, 2023
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
i C22026 - Bloom Multi Family Drainage Report 2nd Round.docx
June 6, 2023
Mr. Wes Lamarque
City of Fort Collins Engineer
4750 Signal Tree Drive
Timnath, CO 80547
RE: Bloom Multi Family Preliminary Design and Erosion Control Report
Project Number: C22026
Dear Wes,
CivilWorx, LLC. is pleased to submit this Preliminary Design and Erosion Control Report for the Bloom Multi
Family Development in Fort Collins, Colorado. This report serves to document the preliminary design plans
for the Bloom Development.
We understand that review by the City of Fort Collins is to assure general compliance with standardized
criteria contained in City of Fort Collins Storm Drainage Design Criteria and Construction Standards. This
report was prepared in compliance with technical criteria set forth in both the Urban Drainage and Flood
Control District (UDFCD) Urban Storm Drainage Criteria Manual and the City of Fort Collins Storm Drainage
Design Criteria.
If you should have any questions or comments as you review this report, please feel free to contact me at
your convenience.
Respectfully,
Kelly W. Hafner, PE
Senior Project Manager
CivilWorx, LLC
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
ii C22026 - Bloom Multi Family Drainage Report 2nd Round.docx
TABLE OF CONTENTS
PAGE
I. General Location and Description ........................................................................................................................ 1
A. Location ....................................................................................................................................................... 1
B. Description of Property ............................................................................................................................... 2
II. Drainage Basins and Catchments ......................................................................................................................... 2
A. Major Basin Description............................................................................................................................... 2
B. Pre-Project Drainage Patterns ..................................................................................................................... 3
III. Drainage Design Criteria ....................................................................................................................................... 3
A. Regulations .................................................................................................................................................. 3
B. Development Criteria Reference and Constraints ....................................................................................... 3
C. Hydrological Criteria .................................................................................................................................... 3
D. Hydraulic Criteria and Governing Standards ............................................................................................... 4
IV. Drainage Facility Design ........................................................................................................................................ 4
A. General Developed Project Overview .......................................................................................................... 4
V. Sediment/Erosion Control .................................................................................................................................... 9
A. Proposed Construction Activities and Phasing ............................................................................................ 9
B. Important Site Areas and Volumes ............................................................................................................ 10
C. Potential Pollutant Sources ....................................................................................................................... 10
D. Water Quality Treatment and LID Practices .............................................................................................. 12
E. Erosion and Sediment Controls ................................................................................................................. 12
F. Erosion Control Sequencing ....................................................................................................................... 15
G. Materials Handling and Spill Prevention .................................................................................................... 17
H. Other Controls ........................................................................................................................................... 18
I. Final Stabilization and Long-term Stormwater Quality.............................................................................. 19
J. Inspection and Maintenance Procedures .................................................................................................. 19
VI. Conclusions ......................................................................................................................................................... 20
A. Compliance with Standards ....................................................................................................................... 20
B. Drainage Plan ............................................................................................................................................. 20
VII. References ...................................................................................................................................................... 21
VIII. Certification .................................................................................................................................................... 21
Figure 1. Vicinity and Phase Map................................................................................................................................... 1
Figure 2. Lower Cooper Slough Drainage Basin – As Shown on the City of Fort Collins Website .................................. 2
Table 1. Existing Catchment Runoff Summary............................................................................................................... 3
Table 2. Developed Catchment Runoff Summary ......................................................................................................... 6
Table 3. Storm Sewer System Summary ........................................................................................................................ 7
Table 4. Inlet Summary .................................................................................................................................................. 8
Table 5. Phasing and Earthwork .................................................................................................................................. 10
APPENDICES
APPENDIX A - Drainage Assessment and Plans
APPENDIX B - Water Quality Calculations
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
1
I. General Location and Description
A. Location
The Bloom Development (referred herein as “the site”) is located north of State Highway 14 (Mulberry
Street) and just west of Interstate 25. The site is located within the southwest half of Section 9, Township
7 North, Range 68 West of the 6th Principal Meridian in the City of Fort Collins, County of Larimer, State of
Colorado. The site is located on the parcel of land # 8709300004 with coordinates of 40.587086, -
105.016334. A vicinity map is shown with Figure 1.
Figure 1. Vicinity and Phase Map
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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B. Description of Property
Currently, the property is undeveloped. There are no structures or significant infrastructure located on
the site. The current use of the property is agriculture and farming and thus the existing land can be
characterized as a tilled field. Below is a detailed summary of the existing conditions:
Ground Cover - The site is currently being used as crop land and therefore ground conditions can
be characterized as tillage/field with varying seasonal crops.
Grades – In general, the entire site drains to the south. These grades are generally less than 1%,
with a few localized areas that slope at approximately 2%.
Soil Type - According to the Natural Resources Conservation (NRCS) web soil survey and report, the
site consists of Garret loam and Ascalon sandy loam soils of hydrologic soils groups Type B and C.
Utilities – The site does not have an existing utilities on it its property. Domestic water, sanitary
sewer, and storm water utilities have been designed and are planned to be built under roads that
will abut the property. Natural gas, telephone, fiber, and electric are planned to be installed in
and around the site at a future time.
Storm Drainage / Irrigation Facilities – The site does not contain any storm drainage infrastructure
except for surface drainage. No irrigation facilities are present on the site.
II. Drainage Basins and Catchments
A. Major Basin Description
This site is located within the Cooper Slough drainage basin as most recently described in the Mulberry
Master Drainage Plan (MDP) by Galloway Engineering Firm and dated April 6th, 2021, with the last revision
of the report being dated as October 13th, 2021.
Figure 2. Lower Cooper Slough Drainage Basin – As Shown on the City of Fort Collins Website
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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B. Pre-Project Drainage Patterns
The project site is located within the Cooper Slough Drainage Basin as shown Figure 2 above. The
proposed site area consists of approximately 15.8 acres. 4 proposed roads that will be constructed as
part of the Bloom 1st Filing Project and shown in the construction plans by Galloway engineering
surround the rectangular property - Aria way on the west, Greenfields Drive on the east, International
Boulevard to the north, and Donella Drive to the south. The entire site drains to the south but the site
is generally flat. The site has localized areas that have grades of approximately 2%, but most grades are
less than 1%. The nearest receiving waters to the site are the Cooper slough drainage and wetlands
(approximately 1,200 feet from the site) that flow into the Boxelder Creek, which further transports
water to the Poudre River. Below is summary of the existing runoff generated by the site as it exists
pre-development.
Table 1. Existing Catchment Runoff Summary
Existing Site Area (ac.) %
Imperv.
Q2
cfs
Q100
cfs
Bloom Property 15.83 2 0.92 19.0
III. Drainage Design Criteria
A. Regulations
The design criteria for this development are the City of Fort Collins Stormwater Drainage Criteria Manual
(FCSDCM) dated March 2018 and the Mile High Flood District Criteria Manuals Volumes 2, and 3 (referred
to herein as MHFDCM).
B. Development Criteria Reference and Constraints
The criteria used as the basis to analyze and design stormwater features of this project were done so
according to the references cited in this report.
C. Hydrological Criteria
In accordance with the City of Fort Collins policy, a minor and major storm are identified as the 2-year and
100-year storms, respectively. These storms have been used as a basis for planning and design. The
proposed developed drainage networks, including the stormwater detention system, are designed using
the USEPA Stormwater Management Model (SWMM version 5.2.3) software. SWMM input parameters
for catchment runoff utilized Table 4.1-1 of the referenced FCSDCM.
Post development runoff for the site will be in accordance with the Mulberry and Greenfields Master
Drainage Plan developed by Galloway Engineering.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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D. Hydraulic Criteria and Governing Standards
The developed site will convey runoff to a proposed detention pond on the southeast corner of the site
via a combination of channelized flow, sheet flow, and storm sewer, then release to the downstream
system per the approved Mulberry and Greenfields Master Drainage Report by Galloway Engineering.
SWMM modeling was used to estimate the required detention pond volume for the Bloom site. Hydraulic
calculations for all pipes and swales were also completed using EPA-SWMM and are included in this
report. SWMM catchment width parameters are calibrated using the theory of cascading planes (see Guo
reference). This method was also documented in the 2016 SWMM Hydrology Reference Manual published
by the EPA.
IV. Drainage Facility Design
A. General Developed Project Overview
The developed Bloom project site area includes the construction of multi-family homes, parking areas,
landscaped areas and access roads. The Bloom multi-family subdivision project is part of the Cooper
Slough basin whose ultimate outfall is the Boxelder Creek, located south of Colorado Highway 14
(Mulberry Street). Runoff from the Bloom-multifamily site will be captured using a combination of curb &
gutter and storm sewer pipe and conveyed to a proposed onsite detention facility. The proposed
detention pond will also include flows from adjacent property to the east, west and north as shown on
the Mulberry and Greenfields Master Drainage Plan by Galloway Engineering. Information on the
proposed Bloom site detention pond outlet structure and storm pipe will be provided by Galloway
engineering at a later date after their analysis incorporates the drainage modeling provided in this report.
Overall Drainage Plan
The overall drainage plan is to convey runoff to the detention facility on the southeast corner of the site
prior to discharging via a proposed outlet structure and storm pipe. Following is an analysis of the site
drainage concepts and routing as well as a summary of all of the proposed on site drainage Catchments.
All flow summaries at design points, including conveyance facilities, have been designed in detail as part
of the EPA SWMM model.
Catchment 01:
The 01 Catchment has an area of 1.85 acres and generally flows to the southeast. Runoff is conveyed via
street flow and channelized curb/gutter/pan flow to a Type C inlet located at the southeastern corner of
the Catchment. From here it is carried through Storm Line A into the proposed-on site detention pond.
Street capacities, inlet sizing, and storm sewer sizing were all completed using EPA-SWMM.
Catchment 02:
The 02 Catchment has an area of 1.32 acres and generally flows to the southeast. Runoff is conveyed via
street flow and channelized curb/gutter/pan flow to a Type C inlet located at the southern side of the
Catchment. From here it is carried through Storm Line C & B and A respectively, after which it drains into
the proposed-on site detention pond. Street capacities, inlet sizing, and storm sewer sizing were all
completed using EPA-SWMM.
Catchment 03:
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Bloom Multi Family Development
Fort Collins, CO
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The 03 Catchment has an area of 1.96 acres, is located at the northeastern portion of the site and generally
flows to the southwest. Runoff is conveyed via street flow and channelized curb/gutter/pan flow to a
Type R inlet located at the southern portion of the Catchment. From here it is carried through Storm Lines
C, B, and A respectively, after which it drains into the proposed-on site detention pond. Street capacities,
inlet sizing, and storm sewer sizing were all completed using EPA-SWMM.
Catchment 04:
The 04 Catchment has an area of 1.4 acres, is located at the northern portion of the site and generally
flows to the south. Runoff is conveyed via street flow and channelized curb/gutter/pan flow to a Type C
inlet located at the south side of the Catchment. From here it is carried through Storm Line A, after which
it drains into the proposed-on site detention pond. Street capacities, inlet sizing, and storm sewer sizing
were all completed using EPA-SWMM.
Catchment 05:
The 05 Catchment has an area of 1.0 acres, is in the central portion of the site and generally flows to the
south. Runoff is conveyed via street flow and channelized curb/gutter/pan flow to a Type R inlet located
at the southern portion of the Catchment. From here it is carried through Storm Lines B and A
respectively, after which it drains into the proposed-on site detention pond. Street capacities, inlet sizing,
and storm sewer sizing were all completed using EPA-SWMM.
Catchment 06:
The 06 Catchment has an area of 0.36 acres, is in the central portion of the site and generally flows to the
south. Runoff is conveyed via street flow and channelized curb/gutter/pan flow to a sidewalk chase/curb
cut where water then travels further south via a grass swale and into the proposed-on site detention
pond. Street capacities, inlet sizing, and storm sewer sizing were all completed using EPA-SWMM.
Catchment 07:
The 07 Catchment has an area of 1.69 acres, is located at the southwestern portion of the site and flows
to the center of itself where a proposed low point and Type R inlet is located. Runoff is conveyed via
street flow and channelized curb/gutter/pan flow to the Type R inlet. From here it is carried north and
east through Storm Lines A, after which it drains into the proposed-on site detention pond. Street
capacities, inlet sizing, and storm sewer sizing were all completed using EPA-SWMM.
Catchment 08:
The 08 Catchment has an area of 2.45 acres and is located at the southwestern portion of the site. This
Catchment is where the proposed detention pond for the site lies, and water eventually leaves the
detention pond via an outlet control structure located at the southwest corner of the Catchment. Overall
pond volume requirements were calculated with EPA-SWMM in conjunction with the Mile High Flood
District Drainage Criteria.
OS Catchments
OS 1: Catchment OS-1 is 0.84 acres, located at the Northwestern portion of the site and drains offsite to
the west via sheet flow and curb and gutter flow. All of the OS-1 flows will be captured in the proposed
Bloom Filing 1 storm sewer infrastructure and directed via storm pipe and inlets back to the proposed-on
site detention pond.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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OS 2: Catchment OS-2 is 0.45 acres, located at the Northwestern portion of the site and drains offsite to
the west via sheet flow and curb and gutter flow. All of the OS-2 flows will be captured in the proposed
Bloom Filing 1 storm sewer infrastructure and directed via storm pipe and inlets to the existing-off site
detention pond located on the north side of International Boulevard.
OS 3: Catchment OS-3 is 0.96 acres, located at the Northern portion of the site and drains offsite to the
north and east via sheet flow and curb and gutter flow. All of the OS-2 flows will be captured in the
proposed Bloom Filing 1 storm sewer infrastructure and directed via storm pipe and inlets back to the
proposed-on site detention pond.
OS 4: Catchment OS-4 is 0.85 acres, located at the western portion of the site and drains offsite to the
west via sheet flow and curb and gutter flow. OS-4 flows will be captured in the proposed Bloom Filing 1
storm sewer infrastructure and directed via storm pipe and inlets to the proposed-on site detention pond.
OS 5: Catchment OS-5 is 0.64 acres, located at the southwestern portion of the site and drains to the west
via sheet flow and curb and gutter flow. OS-5 flows will be captured in the proposed Bloom Filing 1 storm
sewer infrastructure and directed via storm pipe and inlets to the proposed-on site detention pond.
OS 6-10: Catchments OS-6 through OS -10 comprise perimeter and local street catchments that are not
part of the site but are included on the initial drainage plan as designs collaboration continues with the
Galloway project. These catchments comprise of 3.318 acres and made up of areas that will be flowing
to the proposed detention pond that are not on the Bloom-multifamily property and is not included in the
pond WQ calculations provided in appendix B. These Catchments include areas that surrounds the site
located within City of Fort Collins Right-of-Way and includes mostly asphalt and concrete surfaces with
some perimeter landscaping from the site property line to the centerline of each surrounding road.
Drainage Catchment Summaries
The following is a Catchment summary table:
Table 2. Developed Catchment Runoff Summary
Catchment Area
(ac.)
%
Imperv.
C2 Q2
cfs
C100 Q100
cfs
01 1.850 85 0.772 2.5 0.927 14.5
02 1.323 86 0.781 2.0 0.931 11.0
03 1.957 84 0.763 2.5 0.924 15.1
04 1.397 82 0.747 2.1 0.918 11.7
05 1.030 75 0.687 1.5 0.895 8.6
06 0.363 51 0.485 0.5 0.818 3.2
07 1.685 92 0.832 2.4 0.950 13.6
08 2.446 23 0.153 1.1 0.713 18.9
OS-1 0.840 58 0.283 0.4 0.761 6.0
OS-2 0.449 41 0.288 0.2 0.763 3.1
OS-3 0.956 54 0.369 0.5 0.799 6.2
OS-4 0.852 68 0.536 0.9 0.859 7.1
OS-5 0.641 62 0.478 0.7 0.840 5.4
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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Note the infiltration parameters prescribed by the FCSDCM represent fully saturated underlying soil
moisture conditions and thus produce very high runoff rates and volumetric yields.
Storm Sewers
The proposed drainage system for the Bloom Multifamily development was modeled in EPA-SWMM to
determine pipe sizing and flow routing. The SWMM models for the 100-year and 2-year storms are
included in Appendix B for reference.
• Storm Line A – This system drains the western portion of the site to the proposed WQCV
chambers and detention pond. This storm sewer connects to the other storm sewer
networks proposed at the site at STMH A-1-1. This system contains connected Type C
inlets and manholes working in series.
• Storm Line B – This system collects drainage from the central and southern portions of
the site via a type R inlet and receives flows from Storm Line C.
• Storm Line C – This system collects drainage from the eastern central and northern of the
site using 2 Type C inlets and conveys it through Storm Lines B then to the A system
respectively and into the proposed detention pond.
The table below summarizes the pipe flows for the major storm sewer systems for the project:
Table 3. Storm Sewer System Summary
Link Element Q2
cfs
Q100
cfs
Pipe Size Description
STM_A1 11.3 25.4 24” Storm Line A
STM_A-1-1 9.0 18.5 24” Storm Line A-1
STM_A-1-2 3.3 9.4 18” Storm Line A-1
STM_A-1-3 1.7 4.6 18” Storm Line A-1
STM_A2 11.3 25.4 24” Storm Line A-2
STM_A-2-1 2.3 8.1 18” Storm Line A-2
STM_B1 5.8 13.2 24” Storm Line B
STM_C1 3.9 13.0 24” Storm Line C
STM_C2 1.3 3.6 18” Storm Line C
Inlets
The proposed drainage system was modeled in EPA-SWMM. Inlet sizing and intercepted flows were
modeled using the SWMM analysis, with corresponding flowline depths in the street also modeled in
SWMM.
The table below summarizes intercepted flow and flow depths in the curb & gutter at the proposed inlets
for the minor and major storms:
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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Table 4. Inlet Summary
Inlet Name Inlet Type/Size Q2
cfs
Flowline
Depth2
feet
Q100
cfs
Flowline
Depth100
feet
INLET-A1-3 Type C 1.6 0.2 4.8 0.5
INLET-A1-4 Type C 1.7 0.2 4.6 0.5
INLET-A3-1 Type R (10’) 2.4 0.2 8.2 1.0
INLET-B-1 Type R (10’) 2.0 0.1 6.4 0.8
INLET-C-1 Type R (10’) 2.7 0.2 9.5 0.5
INLET-C-3 Type C 1.3 0.2 3.6 0.4
Street Capacity
The proposed drainage system for the development was modeled in SWMM. Street flows and curb &
gutter flow depths were also modeled using the SWMM analysis. The internal gutter system capacity is
presented as adequate for the conveyance of runoff to the perspective outfall.
Detention Pond Summary
Onsite detention was modeled using EPA-SWMM for pond volume and release rate calculations. Water
Quality volume was determined using Mile High Flood District methodologies. These calculations are
included in appendix B. The Bloom site detention pond also includes off-site flows and therefore, final
calculations will be provided at the Master level by Galloway engineering at a later date. Required on site
storage for the Bloom site alone is estimated at 0.623 AF for the 2-year storm and 3.244 AF for the 100-
year storm respectively. The grading design shown on the submitted plans for this facility includes an
active storage of 6.691 AF below spillway and 7.564 AF maximum storage capacity.
Water Quality and LID Design
The site will incorporate water quality capture volume into the proposed detention pond for the
settlement and deposition of particles and contaminants. Sizing and calculations for this water quality
volume and outlet release structure can be found in Appendix B. For additional Low-Impact development
water quality control, an underground stormwater chamber system is proposed with the site that will
treat on-site runoff prior to discharge into the proposed-on site detention pond. Sizing and calculations
for the water quality chamber system can also be found in Appendix B. The intent of the drainage plan is
to install required WQ chambers with the initial construction phase of the project.
It should be noted that the water quality volume provided in the proposed detention pond is for areas
that are not captured first by the proposed-on site water quality chamber system. Catchments that do
not drain to the water quality chamber system are the designated ‘OS’ Catchments as seen in the drainage
map in Appendix A. A summary table of the overall LID treatment coverage for this site is included in
Appendix B.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
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V. Sediment/Erosion Control
In addition to the information provided below, A separate Storm Water Management Plan (SWMP) will
be prepared for the site in accordance with the Stormwater Discharge Permit for Colorado Department
of Public Health and Environment. The SWMP will include more detailed information on the sediment and
erosion control items for this project. The construction plans for the Bloom multi-family development will
be updated to include the SWMP administrator and contact information before construction begins.
Construction phasing, sequencing and use as well as location of project control measures, can be found
in the erosion control plan sheets provided in Appendix A.
A. Proposed Construction Activities and Phasing
Construction of the proposed Bloom site will take place over 2 phases (see Erosion Control/Phasing Map
in Appendix A). For both phases, initial construction activities will begin with clearing and grubbing as well
as topsoil removal and stockpiling. After the site has been cleared of existing vegetation and topsoil,
grading of phase 1 will begin, which will include the installation of temporary erosion control measures.
Once phase 1 has been graded, proposed utilities will be installed. Proposed utilities will include the
installation of underground storm sewer systems (including pipe, manholes, inlets and water quality
control features and systems), sanitary sewer mains and services and water/fire line mains and services.
Following the completion of utility installation subgrade preparation will occur and installation of
hardscape areas will occur. Concrete curb and gutter as well as sidewalks will be installed followed by
paving of the parking areas and access roads. This process will take place in the same order for phase 2.
After infrastructure improvements are complete, all remaining disturbed areas of the site will be re-
seeded to minimize any erosion potential as well as to help eliminate the transport of sediment or
pollutants located on the property. Listed below, are the major aspects of construction in the anticipated
order for each phase of the project:
1.) Initial Erosion Control Measures Installed.
2.) Clearing and grubbing of the site.
3.) Topsoil removal and stockpile.
4.) Grading – includes grading of the proposed detention pond located on the southeast portion of
the site.
5.) Install additional erosion control measures for detention pond, maintenance of existing control
measures.
6.) Installation of utilities – open trenching and installation of proposed utility pipelines and
structures/junctions for storm sewer, sanitary sewer and water infrastructure located on the
site.
7.) Install additional erosion control measures for storm sewer facilities, maintenance of existing
control measures.
8.) Subgrade preparation / final grading of the site in preparation for building pads, and hard
surfaces.
9.) Installation of concrete curb and gutter, drainage pans, sidewalks, miscellaneous concrete pads
and walkways, asphalt paving, and building pads.
10.) Install additional erosion control measures based on these hard surface improvements and
changes in drainage paths, maintenance of existing control measures.
11.) Installation of project lighting as well as required hard surface striping.
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Bloom Multi Family Development
Fort Collins, CO
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12.) Revegetation efforts and stabilization of remaining disturbed areas on the site begins. Work
will include seeding, mulching, installation of sod, and installation of other natural landscape
features provided in the landscaping plan.
13.) Permanent erosion control measures installed; temporary control measures removed.
14.) Final site cleanup and punch list items addressed.
B. Important Site Areas and Volumes
The total area of the project is 15.83 acres which will be divided into two construction phases. Notable
area for each phase and the project total can be seen in the table below.
Table 5. Phasing and Earthwork
Area Staging/Stockpiling
Area (Ac.)
Existing
Imperviousness
(%)
Topsoil
Volume
(CY)
Area of
Disturbance
(Ac.)
Net adjusted,
required import of
materials with
15% compaction
factor (CY)
Phase 1 11.78 0.50 2 6,350 11.78 105,000
Phase 2 4.05 Will be provided at
final submittal
2 2,200 4.05 50,000
Total 15.83 Will be provided at
final submittal
2 7,550 15.83 155,000
C. Potential Pollutant Sources
Listed below are potential pollutant sources that are expected on the site as well as means and methods
to contain and eliminate chances of these sources to be transported off site and to downstream
receiving waters.
1.) Disturbed and Stockpiled Topsoil:
Stockpiled soils generated from grading and utility excavation as well as topsoil stockpiles
will be stored in designated areas for each phase of the project. These stockpile piles shall
not exceed 10 feet in height and shall be located at minimum 50’ away from any proposed
or existing storm inlets or from the proposed-on site detention pond. If these stockpiled soil
piles are anticipated to remain for greater than 30 days, they shall be temporarily seeded.
Silt fence or straw waddles shall be installed around the perimeter of the stockpiles in order
to prevent rainfall events from transporting sediment away from the stockpiles. Disturbed
areas of the site shall be surface roughened to prevent heavy erosion. Locations for
proposed staging / stockpiling areas can be found in Appendix C as part of the interim
erosion control plan.
2.) Vehicle tracking of sediments:
It is anticipated that the contractor will access the property from Lions Gate Drive. A Vehicle
tracking control pad will be required at this access location onsite during construction to
reduce tracking sediment onto the adjacent streets.
At the end of each workday, the Contractor shall sweep or scrape Lions Gate Drive of sediment
that may have accumulated during the workday.
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Bloom Multi Family Development
Fort Collins, CO
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3.) Management of contaminated soils:
There are not any known contaminated soils on the site. However, if the contractor encounters
contaminated soils during the construction process, they should stop construction immediately
and notify the appropriate government authorities in accordance with good construction safety
and practice.
4.) Loading and Unloading operations:
Loading and unloading will take place on the site. Truck access should be limited to the extent
possible to locations within the disturbed limits of the project. BMP’s such as silt fence in non-
paved areas and rock socks in paved areas should be placed to keep sediment from exiting the
disturbed area limits, primarily towards the East as this is the low side of the site.
5.) Outdoor storage activities (building materials, fertilizers, chemicals, etc.):
Storage of onsite materials including building materials, fertilizers, waterline, and sanitary sewer
will be covered and placed on pallets to prevent direct contact with the ground and potential
surface runoff.
6.) Vehicle and equipment maintenance:
Vehicle and equipment maintenance should be performed offsite or onsite within an area
surrounded by silt fence or straw wattles. Vehicle and equipment maintenance shall not happen
along the adjacent public streets. At a minimum, all vehicle and equipment maintenance shall be
performed on the hard surface or gravel areas at least 50’ from any stormwater feature (i.e. inlet,
storm sewer, concentrated runoff, swale, etc.)
7.) Significant dust or particulate generating processes:
The Contractor shall comply with applicable air pollution control requirements of the Town of
Winter Park. The Contractor shall take appropriate actions to minimize atmospheric pollution and
take reasonable precautions which shall include, but not be limited to:
1. The use of water for control of dusts for construction processes such as demolition,
grading, or the clearing of land.
2. Covering, always when in motion, open-bodied trucks transporting materials likely to
give rise to airborne dusts.
3. Require lower speeds for vehicles entering, exiting, and driving within the project limits
to minimize the amount of dust disturbed by moving vehicles.
8.) Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc.;
Chemicals, fuels, lubricants, and paints stored on-site will be in watertight containers and covered
as necessary and stored in a bermed area, a storage building, or within a vehicle to act as
secondary containment.
9.) On-site waste management practices (waste piles, liquid wastes, dumpsters, etc.);
1. Waste piles should be covered or surrounded by silt fence or straw wattles. Liquid wastes
should be collected and stored in covered containers and disposed of properly.
2. Solid waste materials, including disposable materials incidental to the major construction
activities, will be collected in on site dumpsters. The containers will be emptied periodically
and trucked away from the site. Dumpsters should have covers.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
12
10.) Concrete truck / equipment washing, including the concrete truck chute and associated fixtures and
equipment:
A dedicated concrete washout area is necessary for this project. The contractor shall clean out
equipment within the washout area so that runoff is not allowed to leave site and enter the public
streets or neighboring properties.
11.) Dedicated asphalt and concrete batch plants:
There will not be dedicated asphalt or concrete batch plants on this site.
12.) Non-industrial waste sources such as worker trash and portable toilets:
Worker’s trash shall be disposed of in an onsite dumpster. The site should be free of trash at
the end of each working day.
Portable toilets shall be utilized by construction personnel and serviced regularly by a
commercial operator. They shall be located a minimum of 5 feet from the curb or 50 feet from
inlets. If sanitary facilities are located on a paved surface, toilets shall be equipped with a
containment pan or a secondary containment BMP. Regardless of location all portable toilets
shall be anchored per manufacturer recommendations.
13.) Saw cutting and Grinding:
Cutting of pavement or concrete and milling of asphalt is expected to occur during the
project for tie in locations of proposed access roads and utilities. These are are not on the
project property and will be part of city ROW. Nevertheless, water suppression shall be
used to reduce transport of dust during operations. Loose material shall be removed and
disposed of off-site at a proper facility.
14.) Non-Storm Water Discharge:
Other non-storm water components of discharge include, but are not limited to, water line
flushing, irrigation to establish seeding. It is important for the contractor to manage the runoff
from these items utilizing the BMP’s mentioned in this report (i.e. silt fence, straw waddles,
concrete washout areas, surface roughening, etc.).
D. Water Quality Treatment and LID Practices
Water quality for the site will be included with an underground chamber infiltration system and detention
area water quality capture volume for other areas not tributary to the chamber system. The inclusion of
these two approaches is presented as a long-term viable water quality/ LID design for the project.
E. Erosion and Sediment Controls
Once construction activity begins, Best Management Practices (BMP’s) intended to contain sediment
onsite must be constructed, inspected, and repaired as necessary. Such controls must be functional
before upslope land disturbance takes place. The BMP’s will be installed as shown on the SWMP Map
shown in Appendix A. They must be supplemented as on-site experience proves necessary in order to
control sediment, pollutant discharge, and ensure public safety.
The following temporary and permanent BMP’s will be installed and maintained to control on-site erosion
and prevent sediment from traveling off-site during construction.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
13
Temporary Control Measures (BMPs)
• Inlet Protection is a temporary BMP that helps prevent soil and debris from the site from
entering the storm drain inlets and usually consists of a sediment filter around or upstream of
the storm drain inlet. Inlet protection allows storm water to flow into the drain but only after
excess sediment has been filtered out. Inlet protection will be used on existing and proposed
storm inlets and will be installed at such time as construction of the storm sewer system occurs.
Inlet protection for this site will consist of:
• Regular Meetings are a temporary and non-structural BMP. Regular meetings with on-site
workers including builders, suppliers, landscape personnel, etc. should be conducted so that
they are kept up to date with site standard operating procedures.
• Silt Fence is a woven synthetic permeable fabric that filters runoff. Silt fence is a temporary
barrier that is installed prior to earthmoving activities and is placed downstream of areas where
runoff from construction activities is expected to occur, especially along the site perimeter to
allow sediment to settle from runoff before water leaves the construction site. Silt fences will
be installed per manufacturer’s recommendations. Silt fence encourages sheet flow and is not
intended to be used in areas of concentrated flow. If concentrated flow is encountered during
the placement of the fence, an alternative BMP shall be used and the SWMP should be updated
to reflect this change.
• Staging Areas will be provided during the construction process at least 100’ from any storm
water conveyance. Staging areas include locations for vehicle fueling, concrete truck washout,
material storage and transfer, equipment maintenance and cleaning, and other construction
activities. These areas will be maintained as isolated locations that allow for contaminants to be
concentrated and removed from the site as necessary. Concrete washout areas shall be
designed such that washout water cannot leave the location, nor shall storm water runoff wash
concrete from the locations.
• Straw Wattles are a temporary BMP that are used for a variety of purposes. They are used for
inlet protection, curbside check dams, swale protection, at the bottom of slopes, or the limits of
property boundaries. They are easy to install and are increasingly being used for Small Site
SWMP’s. The straw wattles, which are meshed netting “tubes,” filled with straw, excelsior, or
coconut fiber. Wattles for swale protection should be installed following rough grading of
channel areas. Wattles require proper installation and maintenance to ensure their
performance.
• Rock Socks are a temporary BMP that are used for a variety of purposes. They are used for inlet
protection, curbside check dams, or at the limits of property boundaries. Rock socks are wire
meshed “tubes” filled with rocks. Rock Socks require proper installation and maintenance to
ensure their performance.
• Check Dams are a temporary BMP that are used as grade control structures in drainage channels
to limit the erosive nature of stormwater by reducing flow velocity. Check dams are typically
constructed from rock or gravel. Check dams require proper installation and maintenance to
ensure their performance.
• Street Sweeping and Vacuuming removes sediment that has been tracked onto roadways to
reduce sediment transport into storm drain systems or a surface waterway. This practice should
be used on the adjacent paved road to the construction site. Paved roads should be inspected
on a daily basis and more frequently as needed.
• Saw Cutting Pollution Prevention prevents dust and slurry from asphalt and concrete saw
cutting activities from migrating into the existing storm drain system. Slurry and cuttings shall
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
14
be vacuumed during cutting and surface operations and shall not be allowed to remain on
pavement surface overnight. Collected slurry and cuttings shall be disposed of in a manner that
does not violate groundwater or surface water standards.
• Surface Roughening is provided following grading activities to slow the effects of wind erosion.
Roughening can be used as a temporary BMP and is a technique used for creating unevenness
on bare soil through the construction of furrows (groove cuts) running across a slope or by
utilization of construction equipment to track the soil surface. The primary function of surface
roughening is to reduce erosion potential by decreasing runoff velocities, reducing the length of
sheet flow trapping sediment, and increasing infiltration of water into the soil.
• Temporary Seeding is the establishment of a temporary vegetative cover on a graded area that
will be exposed for longer 30 days. Temporary seeding can be used on areas requiring
temporary protection that will eventually need permanent vegetation at the completion of the
construction or it can be used for areas that will be re-disturbed after a period of inactivity. The
seed mix 100% smooth brome at a minimum application rate of 30 pls/lbs/acre. Fertilizer and
Mulch shall be included as specified on the plans.
• Temporary Erosion Control Fabric is comprised of a temporary degradable erosion control
blanket designed to provide immediate erosion protection and vegetation establishment
assistance on moderate slopes and low to medium-flow channels where bare-ground seeding
and loose mulches often fail. Temporary erosion control blankets are being recommended
moderate slopes that do not require permanent turf reinforcement matting.
• Vehicle Tracking Control is a stabilized stone pad located at points of ingress and egress on a
construction site and acts as a temporary BMP. The stone pad is designed to reduce the amount
of mud transported onto public roads by construction traffic by removing mud and sediment
from the vehicle’s wheels when it drives over the gravel pad. These areas are limited to the
minimum number necessary to provide functional construction access and are installed prior to
grading activities. Whenever the construction entrance exists onto a public road, the road shall
be cleaned at the end of each day. Vehicle Tracking Control will also be used on this site at any
stockpile area exits.
• Wattle Sediment Protection is a temporary BMP that are typically used as check structures in
areas of concentrated water flow such as swales, grassed waterways, and down drains. They
can be installed in combination with any type of rolled erosion control blanket or channel liner
and function by slowing water velocity, settling out sediment, and preventing undermining of
the channel lining material. Wattles for swale protection should be installed following rough
grading of channel areas. Sizing and spacing shall be per manufacturer’s recommendation.
• Wind Borne Sediment and Dust Control measures will be provided during the construction
process to control wind borne sediment. During grading activities, water will be applied to the
disturbed soils for the purpose of maintaining cohesion with clay type soils and also to meet
moisture requirements for compaction of disturbed soils. Other measures of mitigation for
wind erosion may include the timely installation of seed and mulch following the establishment
of final grade, and the timely installation of pavement following completion of utility trenching
operations and curb construction. Open areas should be kept in a roughened condition (see
Surface Roughening above).
Permanent Control Measures (BMPs)
• Grass-Lined Swales (included as part of permanent seeding or other permanently stabilized
swales) are permanent landscaped channels constructed generally below grade to convey runoff
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
15
or channel water to a desired location. The grass-lined areas allow for infiltration to occur as
well as including a flow path across a vegetated surface slowing the conveyance rate of storm
water runoff.
• Permanent Seeding and Planting is the establishment of a permanent perennial vegetation such
as trees, shrubs, vines, grasses/sod, or legumes on exposed areas for final permanent
stabilization in order to provide stabilization of the soil by holding soil particles in place. The site
specific re-vegetative seed mix is listed in the table below. Sow seeds at 2-3 lbs, per 1,000
square feet. The application method is hand broadcast spreading and rake in mechanically or by
hand. Slopes over 3:1 should be hayed and tackified or netted with biodegrabale erosion
blankets. Soil Amendments shall be incorporated in all landscape areas to a depth of 6” at a rate
of 3 cubic yards per 1000 square feet of area unless 4” of loose topsoil have been imported onto
the site over 4” of loosened subgrade soils. Permanent Landscaping reduces storm water runoff
velocity, maintains sheet flow, protects the soil surface from erosion, promotes infiltration of
runoff, and improves wildlife habitat.
• Preservation of Existing Vegetation should occur where no construction activity is expected to
occur. Preservation of natural vegetation is generally a permanent BMP and is applicable to
construction sites with pre-existing vegetation. Only land needed for building activities and
vehicle traffic needs is to be cleared.
• Storm Sewer Outlet Protection devices are structurally lined aprons or other energy dissipating
devices placed at the outlets of pipes or paved channel sections. Outlet protection devices
prevent scour at storm water outlets and minimize the potential of downstream erosion by
reducing the velocity of storm water flows. Turf reinforcement matting will be used
downstream of storm sewer outfalls as pipe outlet protection. Outlet Protection is installed
with the storm sewer construction and serves as a permanent structural BMP.
F. Erosion Control Sequencing
This project will have three distinct erosion control phases. The initial phase will be installing
erosion control items prior to any construction on the site. After the initial erosion control items
have been installed, the next phase will consist of site demolition, grading activities and construction
of the infrastructure (utilities, storm sewer, and development of landscaped areas). The final stage
will include the construction of the site hard surfaces including roads, parking areas, curb and gutter,
concrete sidewalk and island areas and finally ending in stabilization of all remaining disturbed areas
of the site. Each of the phases is described below, including necessary erosion control items.
A SWMP drawing is located in the Appendix that includes the minimum required BMP’s found on
the Sediment and Erosion Control Plans. It should be filled in with the appropriate BMP’s as they
are constructed/placed within the project site.
Sequence 1 – Initial, Prior to Construction
• Silt Fence – Before construction commencement, silt fence will be placed
downstream of areas where runoff from construction activities is expected to occur.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
16
• Staging Area – A concrete wash out area, fueling area, and other staging areas will
be provided during the construction process at least 100’ from any storm water
conveyance. A staging area is to be shown on the SWMP drawing when its location
is identified.
• Vehicle Tracking Control – Before commencement of construction, vehicle tracking
control shall be placed at the location shown west of Overland Trail along West
Elizabeth Street. Any other points of ingress and egress planned by the contractor
and approved by the owner shall also receive suitable vehicle tracking control
BMP's.
• Construction Fence – Before commencement of construction, construction fence
shall be placed at the contractor’s discretion (or as shown in the plans) to limit
access by construction equipment and personal vehicles to designated areas of
ingress and egress.
• Stage/stockpiles – Designate stockpile/staging location per erosion control initial
sequence map included in appendix A. Strip topsoil and store at this location and be
sure to surround the stockpile (s) with silt fence or straw wattles.
Sequence 2 – Site Demolition, Site Grading, and Infrastructure Construction
The items installed in sequence 1 shall be in place, functional, and maintained during
and following the site demolition and site grading operations. In addition to those
items, the following BMP’s shall be installed.
• Wind Borne Sediment and Dust Control – Wind borne sediment and dust control
measures should be implemented during grading activities. This will be particularly
important to consider prior to the establishment of seeding.
• Inlet Protection – Wattles will be placed at curb inlets and area inlets located
throughout the site immediately after the inlet is constructed / installed. Existing
inlets shall be protected prior to heavy equipment staging, demolition, or
commencement of construction activities.
• Swale Protection – Straw wattles and check dams will be placed within the swales
immediately following rough grading. Wattles and check dams shall be placed
across the swale for every 2’ of drop in swale elevation or every 300'.
• Slope Protection – Surface roughening and contour furrows shall occur after rough
grading.
• Temporary Seeding – The majority of the landscaped areas will be permanently
seeded or planted. However, if disturbed areas are left without permanent
stabilization 30 days after grading, temporary seeding will be required.
• Outlet Protection– Riprap and/or permanent turf reinforcement matting will be
placed immediately downstream of storm sewer outfalls.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
17
• Concrete Washout Area – Concrete washout areas will be placed prior to, and
maintained during, the completion of concrete work.
• Inlet Protection – Wattles will be placed at curb inlets and area inlets located
throughout the site immediately after the inlet is constructed / installed. Existing
inlets shall be protected prior to heavy equipment staging, demolition, or
commencement of construction activities.
• Rock Socks – Rock socks will be placed to replace other inlet protection devices as
required after paving operations have been completed.
Sequence 3 - Building and roadway construction
This sequence will likely begin before the seeding has been established throughout the
site, so it is expected that majority of the BMP’s shown in Phase 1 and Phase 2 will be in
place at the beginning of this phase. As roads are paved and seeding is established
there will be previously placed BMP's such as vehicle tracking control devices and some
sections of silt fence that may be removed. There are other items such as inlet
protection, silt fence, and swale protection that may only be removed after all
construction is complete and upstream areas are established.
• Permanent Seeding – Permanent seeding or landscaping shall be placed
immediately in areas that are final graded and where little future disturbance is
expected.
• Rock Socks – Rock socks will be placed to replace other inlet protection devices as
required after paving operations have been completed.
G. Materials Handling and Spill Prevention
The site development includes appropriate construction staging and stockpile areas
identified on the SWMP Plans shown in Appendix A. Stormwater runoff generated from
the staging areas will be routed to a temporary sedimentation area where runoff will be
contained and filtered before being discharged downstream. The staging/stockpile
area(s) may be moved to a location no closer than 100’ from a storm water conveyance.
Vehicle tracking control should be placed at the stockpile area entrance/exit and silt
fence should surround it. If relocated, the SWMP should be updated with the actual
location of the stockpile/staging area(s).
Chemicals, fuels, lubricants, and paints stored on-site will be in water tight containers
and covered as necessary and stored in a bermed area, a storage building, or within a
vehicle to act as secondary containment. Storage of onsite materials including building
materials, fertilizers, waterline, sanitary sewer, and storm sewer will be covered and
placed on pallets to prevent direct contact with the ground and potential surface runoff.
Concrete and asphalt batch plants are not anticipated on this site and thus are not
included in this SWMP.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
18
In the event of a spill or accident, it shall be contained and disposed of so that it will not
flow from the site or soak into the soil. Once construction is completed, concrete waste
and contaminated soil will be disposed of properly. The SWMP Administrator should be
notified of spills.
Reporting Spills: Any spill or discharge of any pollutant, including but not limited to oil,
paints, fuels, hazardous liquids, sediment, or super-chlorinated water that reaches
storm drains or enters “Waters of the State” must be reported to the CDPHE
Emergency Spill Reporting line at 1-877-518-5608.
If a spill or leak is of a hazardous substance that exceeds 1 pint or is of an unknown
substance of any amount, call 911 and notify the Colorado Department Public Health
and Environment (CDPHE) 24-hour emergency spill notification hotline at 1- 877-518-
5608, immediately. If the spill is more than 25 gallons of a petroleum product from a
regulated storage tank or delivery truck or any amount that causes a sheen on nearby
surface water, it must be reported to the Division of Oil and Public Safety at the
Colorado Department of Labor and Employment within 24 hours at (303) 318-8547 or to
CDPHE Emergency Spill Reporting line at 1-877-518-5608 – if after normal business
hours. If cleanup cannot be accomplished within 24 hours, the Division of Oil and Public
Safety must be notified immediately. For non-emergency spills, call 970-674-2490. Spills
shall also be reported to the onsite supervisor.
H. Other Controls
The following includes other measures to control pollutants:
• Solid waste materials, including disposable materials incidental to the major
construction activities, will be collected in containers. The containers will be
emptied periodically and trucked away from the site. Dumpsters shall have covers.
• Water used to establish and maintain grass, for dust control, and for other purposes
during the construction phase must originate from a public water supply or private
well approved by the Colorado Department of Public Health and Environment unless
otherwise approved.
• Sanitary facilities shall be provided at the site throughout construction activities.
They shall be utilized by construction personnel and serviced regularly by a
commercial operator. They shall be located a minimum of 5 feet from the curb or
50 feet from inlets and must be anchored. If sanitary facilities are located on a
paved surface, a secondary containment BMP will need to be constructed.
• Access off paved roads should be limited.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
19
I. Final Stabilization and Long-term Stormwater Quality
Final stabilization is reached when all soil disturbing activities at the site have been completed
and vegetative cover has been established with a density of at least 70 percent of pre-
disturbance levels or when equivalent permanent erosion reduction methods have been
utilized. Upon final stabilization, temporary BMP’s may be removed, unless they are required to
remain in place for future phasing.
Water quality enhancements are provided in areas where grass-lined swales are provided for
storm water conveyance. The soft bottom/overbank areas allow for infiltration to occur as well
as including a flow path across a vegetated surface slowing the conveyance rate of storm water
runoff.
Temporary and Permanent seeding will be implemented on the site as well as other plantings
that will be implemented based off a landscape architectural plan as required by the local
jurisdiction where the site exists.
J. Inspection and Maintenance Procedures
Upon completion of each phase of construction, appropriate measures shall be taken to inspect
and maintain existing erosion control features, as described herein or per manufacturers
specifications (whichever is more stringent) and install new erosion control elements associated
with each phase of construction.
The temporary BMP’s will be inspected and documented at a minimum of once every 14 days and
after each precipitation or snowmelt event. The SWMP will be kept up-to-date with inspection
records, maintenance procedures, and changes. Records should include complete inspection
reports for each inspection, maintenance, and/or repair. A record-keeping system is
recommended in managing inspection and maintenance reports and should include all
maintenance records, spill response, weather conditions, training, correspondence, etc. A blank
copy the CDOT Stormwater Field Inspection Report is provided in Appendix C.
Preventative maintenance also involves the regular inspection and testing of equipment, timely
maintenance of the equipment, and complete records of the maintenance and inspections of the
equipment. The maintenance and inspection records should be kept on site and made available
upon request.
Inspections must include the observation of the construction site perimeter, runoff discharge
points, disturbed areas, staging areas (including concrete washout areas and fueling areas),
erosion and sediment control measures identified in this SWMP, and any other structural BMP’s
that may require maintenance. The inspection must determine if there is evidence of or potential
for pollutants to enter the drainage system and if they should be modified, replaced, or added to.
The following list includes some recommended maintenance procedures:
• Erosion and sediment control measures determined, upon inspection, to be in need of repair
shall be maintained before the next anticipated storm event or as necessary to maintain
continued effectiveness of erosion and sediment control measures. If it is impractical to
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
20
maintain erosion and sediment control measures before the next storm event, maintenance
should be accomplished as soon as practical.
• Locations where vehicles enter or exit the site shall be inspected for evidence of sediment
being tracked off-site by construction traffic. Such sediment shall be removed before it can
be conveyed to the receiving storm drains or creeks.
• Seeded areas will be checked to see that grass coverage is maintained. Areas will be watered,
fertilized, and reseeded as needed.
VI. Conclusions
A. Compliance with Standards
Storm drainage calculations have followed the guidelines provided by the City of Fort Collins Stormwater
Criteria manual and the Mile High Flood District Manuals Volumes 2, and 3.
B. Drainage Plan
The drainage system is not anticipated to have issues associated with conveyance, collection or detention
based on the work to date in the subdivision planning. No negative impacts are expected due to this
development as related to the existing downstream drainage networks or subdivisions. The preliminary
drainage plan for the Bloom multifamily development is submitted as being both viable and sound in
terms of drainage planning in both the short- and long-term for the City of Fort Collins.
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
21
VII. References
1. City of Fort Collins Stormwater Criteria Manual, As adopted by the City Council of the City of
Fort Collins, as referenced in Section 26-500 of the Code of the City of Fort Collins, Revised
December 2018.
2. Mile High Floor District Drainage Criteria Manuals 2 and 3, Urban Drainage and Flood Control
District, Denver, Colorado, November 2010 with some sections revised January 2021.
3. Storm Water Management Model, Reference Manual Volume I, Hydrology, U.S.
Environmental Protection Agency, January 2016.
4. Storm Water Management Model, Reference Manual Volume II, Hydraulics, U.S.
Environmental Protection Agency, May 2017.
5. Mulberry Master Drainage Report, City of Fort Collins – Galloway, revised October 13th, 2021.
6. Conversion of Natural Watershed to Kinematic Wave Cascading Plane, Guo, J.C.Y. and
Urbonas, B., Journal of Hydrologic Engineering, Vol. 14, No. 8, pp. 839-846, July/August 2009.
VIII. Certification
"I hereby attest that this report for the preliminary drainage design of the Bloom Development was prepared
by me, or under my direct supervision, in general accordance with the provisions of the City of Fort Collins
Storm Drainage Design Criteria for the responsible parties thereof. I understand that the City of Fort
Collins does not and shall not assume liability for drainage facilities designed by others.”
<Review Draft until notice of approval>
_____________________________________
Kelly W. Hafner
Registered Professional Engineer
State of Colorado No. 40968
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
1
APPENDIX A
DRAINAGE AND EROSION CONTROL PLAN MAPS
EROSION CONTROL ESCROW CALCULATIONS
100-YEAR SWMM MODEL REPORT
DRAINAGE AND EROSION CONTROL PLAN MAPS
EROSION CONTROL ESCROW CALCULATIONS
TEEEEEEEEEEEETTTTTTTTTTTTCLUBHOUSE
A A A
B
B
E B
STORM LINE A
STORM LINE A:
STORM LINE C:
STORM LINE B:
24" STM SWR
WQ CHAMBERS
SYSTEM
STORM LINE C:
SDI A1-4
SDI C-3
SDMH A1-2
SDI A1-3
SDMH A1-1
SDMH C-2
SDI C-1
SDMH A-4
SDMH A-3
SDMH A-2-1
SDMH A-2-2
SDMH A-2
SDI B-1
SDI A3-1
FES A-1 24"24"24"18"
18"18"18"18"
18"18"18"18"
18
"
18"
01
1.85 85%
02
1.323 86%
03
1.96 84%
04
1.40 82%
05
1.03 75%
06
0.36 51%
07
1.69 92%
08
2.446 23%
OS-1
0.84 58%
OS-3
0.96 54%
OS-4
0.85 68%
OS-5
0.64 62%
OS-6
0.71 88%
OS-2
0.46 10%
OS-7
0.75 88%
OS-8
0.47 88%
OS-9
1.27 88%
OS-10
0.2 95%DRAINAGE PLAN1" = 60'
1" = 60'
12
DN01 PREPARED FOR: JOB NUMBER
SHEET NUMBER
SHEETSOF DATE SUBMITTED:The engineer preparing these plans will not be responsiblefor, or liable for, unauthorized changes to or uses of theseplans. All changes to the plans must be in writing andmust be approved by the preparer of these plans.NO.BYDATECAUTIONREVISIONS:VERTICAL:
HORIZONTAL:
SCALE
4025 Automation Way
Suite B2
Fort Collins, CO 80525
(970) 698-6046
CivilWorxeng.com
BLOOM MULTI-FAMILY DEVELOPMENTC22026 HARTFORD HOMES06/06/202339
PRELIMINARY
NOT FOR
CONSTRUCTION
00 60'120'
SCALE: 1" = 60'
30'PHASE 2KEYMAP
NTS
LEGEND
MAPPING / SITE
PROPERTY BOUNDARY
RIGHT-OF-WAY
LOT LINES
EASEMENTS
CENTER LINE
CURB AND GUTTER
EXISTING CONTOURS
PROPOSED CONTOURS
PHASING LINE
PROPOSED UTILITIES
STORM DRAIN PIPE
FLARED END SECTION
STORM DRAIN INLET
STORM DRAIN OUTLET
RIP RAP
NOTES
1.SEE GRADING SHEETS FOR ADDITIONAL
SPOT ELEVATIONS FOR THE PROJECT.
2.SEE EROSION CONTROL PLANS FOR
ADDITIONAL INFORMATION.
EXISTING UTILITIES
STORM DRAIN PIPE
FLARED END SECTION
STORM DRAIN INLET
STORM DRAIN OUTLET
RIP RAP
D-101
GRADING
BASIN BOUNDARY
DESIGN POINT
BASIN LABEL
BASIN IMPERVIOUSNESS
BASIN AREA
FLOW DIRECTIONPHASE 1
IP
SFSFSF
SF
SF
SF
SF
SFVTC
A
SF
VTC
PROJECT LIMITS OF DISTURBANCE
PHASE 1: 12.78 ACRES
PHASE 2: 3.72 ACRES
TOTAL: 16.50 ACRES
CWA
RS
A
A
EROSION CONTROL PLAN - INITIAL1" = 60'
1" = 60'
13
EC01 PREPARED FOR: JOB NUMBER
SHEET NUMBER
SHEETSOF DATE SUBMITTED:The engineer preparing these plans will not be responsiblefor, or liable for, unauthorized changes to or uses of theseplans. All changes to the plans must be in writing andmust be approved by the preparer of these plans.NO.BYDATECAUTIONREVISIONS:VERTICAL:
HORIZONTAL:
SCALE
4025 Automation Way
Suite B2
Fort Collins, CO 80525
(970) 698-6046
CivilWorxeng.com
BLOOM MULTI-FAMILY DEVELOPMENTC22026 HARTFORD HOMES06/06/202339
PRELIMINARY
NOT FOR
CONSTRUCTION
00 60'120'
SCALE: 1" = 60'
30'
PHASE 2
TOTAL PROJECT
DISTURBED AREA 16.50 ACRES
TOTAL "ONSITE" AREA
OF DISTURBANCE 15.91 ACRES
TOTAL "OFFSITE" AREA
OF DISTURBANCE 0.59 ACRES
TOTAL
STORAGE/STAGING
AREA
0.5000 ACRES
TOTAL HAUL ROADS
AREA N/A
CONSTRUCTION
VEHICLE TRAFFIC AREA N/A
ESTIMATED PERCENT
OF PROJECT AREA
EXPOSED
100%
ESTIMATED PERCENT
VEGETATIVE COVER ~95%DENSITY
EXISTING SOIL TYPE TYPE B & C SANDY/LOAM
GROUNDWATER DEPTH FEET
NUMBER OF PHASES
W/PROJECT 2
TOTAL VOUME OF
IMPORTED (+) /
EXPORTED (-)
MATERIALS
(+) 155,000 CUBIC YARDS
TOTAL AREA OF
STOCKPILING OF FILL
OR BORROW AREAS OFF
SITE
SQUARE FEET
STEEPEST SLOPE 4 H:V
DISTANCE FROM A
RIPARIAN AREA OF
SENSITIVE AREA
1,200 FEET
KEYMAP
NTS
LEGEND
MAPPING / SITE
PROPERTY BOUNDARY
RIGHT-OF-WAY
LOT LINES
CENTER LINE
CURB AND GUTTER
PHASING LINE
EROSION CONTROL
VEHICLE TRACKING
CONTROL PAD
WATTLE DIKE
TEMPORARY SEDIMENT
INLET PROTECTION
TURF REINFORCEMENT MAT
SILT FENCE
STOCKPILE MANAGEMENT
SURFACE ROUGHENING
CONCRETE WASHOUT
STRUCTURE
PERMANENT SEEDING
SILT FENCE TO BE REMOVED
PERIMETER PROTECTION
DURING BUILDING
CONSTRUCTION
NOTES
1.THE CONTRACTOR IS RESPONSIBLE FOR
VERIFYING THE FIELD CONDITIONS ARE AS
SHOWN IN THE DRAWINGS. IF THE
CONTRACTOR FINDS DISCREPANCIES THE
CONTRACTOR SHALL CONTACT THE
ENGINEER.
2.ALL DISTURBED AREAS SHALL BE
REVEGETATED.
3.EROSION CONTROL PRACTICES, SITE
PROTECTION, AND REVEGETATION
METHODS SHALL FOLLOW CITY
REGULATIONS.
4.IN ADDITION TO THE EROSION CONTROL
MEASURES SHOWN ON THIS DRAWING, THE
CONTRACTOR SHALL COMPLETE,
COORDINATE WITH, AND UPDATE AS
REQUIRED, THE STORMWATER POLLUTION
PREVENTION PLAN (SWPP) FOR THIS
PROJECT.
5.CONTRACTOR TO TERRACE SLOPES USING
A "TRACKED" VEHICLE, RUN
PERPENDICULAR TO SLOPE TO INHIBIT
RILL/GULLEY EROSION, CONTRACTOR MAY
USE OTHER WINDROW-TYPE METHODS AS
APPROVED BY ENGINEER. TYPICAL ALL
SLOPES, REPEAT AS NECESSARY UNTIL
LANDSCAPING IS INSTALLED.
6.ANY AREAS USED FOR STOCKPILING
AND/OR STAGING SHOULD ALSO HAVE
SEDIMENT AND EROSION CONTROL
MEASURES AS NECESSARY. THESE AREAS
SHOULD BE LOCATED AT LEAST 100' AWAY
FROM DRAINAGE WAYS. THE SWMP
SHOULD BE UPDATED TO SHOW THESE
AREAS AND SEDIMENT AND EROSION
CONTROL ITEMS. THE ITEMS MAY INCLUDE
BUT ARE NOT LIMITED TO VEHICLE
TRACKING CONTROL, SILT FENCE,
CONSTRUCTION FENCE, CONCRETE
WASHOUT, AND SEDIMENT TRAP.
7.TEMPORARY SEEDING OR TACKIFER
PLACEMENT SHALL BE UTILIZED IN THE
EVENT THAT A GRADED AREA IS EXPOSED
LONGER THAN 14 DAYS WITH NO
CONSTRUCTION ACTIVITY.
8.TURF REINFORCEMENT MAT SHALL BE
PYRAMAT OR APPROVED EQUAL.
9.CONTRACTOR SHALL REMOVE ALL
SEDIMENT, MUD, CONSTRUCTION DEBRIS,
OR OTHER POTENTIAL POLLUTANTS THAT
MAY HAVE BEEN DISCHARGED TO OR,
ACCUMULATE IN, THE FLOW LINES AND
PUBLIC RIGHTS-OF-WAY OF THE CITY, AS A
RESULT OF CONSTRUCTION ACTIVITIES
ASSOCIATED WITH THIS DEVELOPMENT OR
CONSTRUCTION PROJECT. SAID REMOVAL
SHALL BE CONDUCTED DAILY, AS MAY BE
REQUIRED. SUCH MATERIALS SHALL BE
PREVENTED FROM ENTERING THE STORM
SEWER.
10.THE PROJECT LANDSCAPE PLAN WILL
CONTAIN THE DETAILED INFORMATION
REGARDING REQUIRED SEED TYPES/MIXES.
11.SEE THE GENERAL NOTES SHEETS FOR ALL
OF THE CITY OF FORT COLLINS EROSION
CONTROL NOTES.
VTC
WD
TS
IP
TRM
SF
LIMITS OF DISTURBANCE
RIP RAP
FLOW DIRECTION
SF
SRSR
CWA
PSPS
A
B
BBBB
B B
B
B
PHASE 1
PHASE 1 STOCKPILE
Implementation Timeline: Initial Overlot Grading Prior to Utility Construction
IP
IP
IP
IP
IP
IP
SFSFSF
SF
SF
A
SF
SFVTC
TS
4.8:1
4.1:1
3.8:14.1:17.3:15.1:15.2:14.3:14.6:14.3:1SF
SF
VTC
SR
SR
SR
SR
SR
SR
PROJECT LIMITS OF DISTURBANCE
PHASE 1: 12.78 ACRES
PHASE 2: 3.72 ACRES
TOTAL: 16.50 ACRES
CWA
WD
WDWD
WD
WD
WD
WD
WD
WD
WD
WDWD
WD
WD
WD WD
WD WD
WD WD
WD
WD
WD WD
WD
WD
WD
WD
WD
WD
WD
WD
WD
WD
WD
WD
WDWD
SR SR
SR SR
SRSRSR SR
SR
RS
IP
A
WD
EROSION CONTROL PLAN - INTERIM1" = 60'
1" = 60'
14
EC02 PREPARED FOR: JOB NUMBER
SHEET NUMBER
SHEETSOF DATE SUBMITTED:The engineer preparing these plans will not be responsiblefor, or liable for, unauthorized changes to or uses of theseplans. All changes to the plans must be in writing andmust be approved by the preparer of these plans.NO.BYDATECAUTIONREVISIONS:VERTICAL:
HORIZONTAL:
SCALE
4025 Automation Way
Suite B2
Fort Collins, CO 80525
(970) 698-6046
CivilWorxeng.com
BLOOM MULTI-FAMILY DEVELOPMENTC22026 HARTFORD HOMES06/06/202339
PRELIMINARY
NOT FOR
CONSTRUCTION
00 60'120'
SCALE: 1" = 60'
30'
PHASE 2
TOTAL PROJECT
DISTURBED AREA 16.50 ACRES
TOTAL "ONSITE" AREA
OF DISTURBANCE 15.91 ACRES
TOTAL "OFFSITE" AREA
OF DISTURBANCE 0.59 ACRES
TOTAL
STORAGE/STAGING
AREA
0.5000 ACRES
TOTAL HAUL ROADS
AREA N/A
CONSTRUCTION
VEHICLE TRAFFIC AREA N/A
ESTIMATED PERCENT
OF PROJECT AREA
EXPOSED
100%
ESTIMATED PERCENT
VEGETATIVE COVER ~95%DENSITY
EXISTING SOIL TYPE TYPE B & C SANDY/LOAM
GROUNDWATER DEPTH FEET
NUMBER OF PHASES
W/PROJECT 2
TOTAL VOUME OF
IMPORTED (+) /
EXPORTED (-)
MATERIALS
(+) 155,000 CUBIC YARDS
TOTAL AREA OF
STOCKPILING OF FILL
OR BORROW AREAS OFF
SITE
SQUARE FEET
STEEPEST SLOPE 4 H:V
DISTANCE FROM A
RIPARIAN AREA OF
SENSITIVE AREA
1,200 FEET
KEYMAP
NTS
LEGEND
MAPPING / SITE
PROPERTY BOUNDARY
RIGHT-OF-WAY
LOT LINES
CENTER LINE
CURB AND GUTTER
PHASING LINE
EROSION CONTROL
VEHICLE TRACKING
CONTROL PAD
WATTLE DIKE
TEMPORARY SEDIMENT
INLET PROTECTION
TURF REINFORCEMENT MAT
SILT FENCE
STOCKPILE MANAGEMENT
SURFACE ROUGHENING
CONCRETE WASHOUT
STRUCTURE
PERMANENT SEEDING
SILT FENCE TO BE REMOVED
PERIMETER PROTECTION
DURING BUILDING
CONSTRUCTION
NOTES
1.THE CONTRACTOR IS RESPONSIBLE FOR
VERIFYING THE FIELD CONDITIONS ARE AS
SHOWN IN THE DRAWINGS. IF THE
CONTRACTOR FINDS DISCREPANCIES THE
CONTRACTOR SHALL CONTACT THE
ENGINEER.
2.ALL DISTURBED AREAS SHALL BE
REVEGETATED.
3.EROSION CONTROL PRACTICES, SITE
PROTECTION, AND REVEGETATION
METHODS SHALL FOLLOW CITY
REGULATIONS.
4.IN ADDITION TO THE EROSION CONTROL
MEASURES SHOWN ON THIS DRAWING, THE
CONTRACTOR SHALL COMPLETE,
COORDINATE WITH, AND UPDATE AS
REQUIRED, THE STORMWATER POLLUTION
PREVENTION PLAN (SWPP) FOR THIS
PROJECT.
5.CONTRACTOR TO TERRACE SLOPES USING
A "TRACKED" VEHICLE, RUN
PERPENDICULAR TO SLOPE TO INHIBIT
RILL/GULLEY EROSION, CONTRACTOR MAY
USE OTHER WINDROW-TYPE METHODS AS
APPROVED BY ENGINEER. TYPICAL ALL
SLOPES, REPEAT AS NECESSARY UNTIL
LANDSCAPING IS INSTALLED.
6.ANY AREAS USED FOR STOCKPILING
AND/OR STAGING SHOULD ALSO HAVE
SEDIMENT AND EROSION CONTROL
MEASURES AS NECESSARY. THESE AREAS
SHOULD BE LOCATED AT LEAST 100' AWAY
FROM DRAINAGE WAYS. THE SWMP
SHOULD BE UPDATED TO SHOW THESE
AREAS AND SEDIMENT AND EROSION
CONTROL ITEMS. THE ITEMS MAY INCLUDE
BUT ARE NOT LIMITED TO VEHICLE
TRACKING CONTROL, SILT FENCE,
CONSTRUCTION FENCE, CONCRETE
WASHOUT, AND SEDIMENT TRAP.
7.TEMPORARY SEEDING OR TACKIFER
PLACEMENT SHALL BE UTILIZED IN THE
EVENT THAT A GRADED AREA IS EXPOSED
LONGER THAN 14 DAYS WITH NO
CONSTRUCTION ACTIVITY.
8.TURF REINFORCEMENT MAT SHALL BE
PYRAMAT OR APPROVED EQUAL.
9.CONTRACTOR SHALL REMOVE ALL
SEDIMENT, MUD, CONSTRUCTION DEBRIS,
OR OTHER POTENTIAL POLLUTANTS THAT
MAY HAVE BEEN DISCHARGED TO OR,
ACCUMULATE IN, THE FLOW LINES AND
PUBLIC RIGHTS-OF-WAY OF THE CITY, AS A
RESULT OF CONSTRUCTION ACTIVITIES
ASSOCIATED WITH THIS DEVELOPMENT OR
CONSTRUCTION PROJECT. SAID REMOVAL
SHALL BE CONDUCTED DAILY, AS MAY BE
REQUIRED. SUCH MATERIALS SHALL BE
PREVENTED FROM ENTERING THE STORM
SEWER.
10.THE PROJECT LANDSCAPE PLAN WILL
CONTAIN THE DETAILED INFORMATION
REGARDING REQUIRED SEED TYPES/MIXES.
11.SEE THE GENERAL NOTES SHEETS FOR ALL
OF THE CITY OF FORT COLLINS EROSION
CONTROL NOTES.
VTC
WD
TS
IP
TRM
SF
LIMITS OF DISTURBANCE
RIP RAP
FLOW DIRECTION
SF
SRSR
CWA
PSPS
A
B
BBBB
B B
B
B
PHASE 1
PHASE 1 STOCKPILE
Implementation Timeline: Utility Installation and Building Construction
TEEEEEEEEEEEETTTTTTTTTTTTIP
4.8:1
4.1:1
3.8:14.1:17.3:15.1:15.2:14.3:14.6:14.3:1PROJECT LIMITS OF DISTURBANCE
PHASE 1: 12.78 ACRES
PHASE 2: 3.72 ACRES
TOTAL: 16.50 ACRES
PS
PS
PS
PS
PS
PS
PS
PS
PS
PS
PS
PS
PS
PS
PSPS
PS
PS
PS
IPIP
IP
IP
IP
PS
PS
PS
PSPSPSPSPSPS
PS
PS
PSPS
IP
EROSION CONTROL PLAN - FINAL1" = 60'
1" = 60'
15
EC03 PREPARED FOR: JOB NUMBER
SHEET NUMBER
SHEETSOF DATE SUBMITTED:The engineer preparing these plans will not be responsiblefor, or liable for, unauthorized changes to or uses of theseplans. All changes to the plans must be in writing andmust be approved by the preparer of these plans.NO.BYDATECAUTIONREVISIONS:VERTICAL:
HORIZONTAL:
SCALE
4025 Automation Way
Suite B2
Fort Collins, CO 80525
(970) 698-6046
CivilWorxeng.com
BLOOM MULTI-FAMILY DEVELOPMENTC22026 HARTFORD HOMES06/06/202339
PRELIMINARY
NOT FOR
CONSTRUCTION
00 60'120'
SCALE: 1" = 60'
30'
PHASE 2
TOTAL PROJECT
DISTURBED AREA 16.50 ACRES
TOTAL "ONSITE" AREA
OF DISTURBANCE 15.91 ACRES
TOTAL "OFFSITE" AREA
OF DISTURBANCE 0.59 ACRES
TOTAL
STORAGE/STAGING
AREA
0.5000 ACRES
TOTAL HAUL ROADS
AREA N/A
CONSTRUCTION
VEHICLE TRAFFIC AREA N/A
ESTIMATED PERCENT
OF PROJECT AREA
EXPOSED
100%
ESTIMATED PERCENT
VEGETATIVE COVER ~95%DENSITY
EXISTING SOIL TYPE TYPE B & C SANDY/LOAM
GROUNDWATER DEPTH FEET
NUMBER OF PHASES
W/PROJECT 2
TOTAL VOUME OF
IMPORTED (+) /
EXPORTED (-)
MATERIALS
(+) 155,000 CUBIC YARDS
TOTAL AREA OF
STOCKPILING OF FILL
OR BORROW AREAS OFF
SITE
SQUARE FEET
STEEPEST SLOPE 4 H:V
DISTANCE FROM A
RIPARIAN AREA OF
SENSITIVE AREA
1,200 FEET
KEYMAP
NTS
LEGEND
MAPPING / SITE
PROPERTY BOUNDARY
RIGHT-OF-WAY
LOT LINES
CENTER LINE
CURB AND GUTTER
PHASING LINE
EROSION CONTROL
VEHICLE TRACKING
CONTROL PAD
WATTLE DIKE
TEMPORARY SEDIMENT
INLET PROTECTION
TURF REINFORCEMENT MAT
SILT FENCE
STOCKPILE MANAGEMENT
SURFACE ROUGHENING
CONCRETE WASHOUT
STRUCTURE
PERMANENT SEEDING
SILT FENCE TO BE REMOVED
PERIMETER PROTECTION
DURING BUILDING
CONSTRUCTION
NOTES
1.THE CONTRACTOR IS RESPONSIBLE FOR
VERIFYING THE FIELD CONDITIONS ARE AS
SHOWN IN THE DRAWINGS. IF THE
CONTRACTOR FINDS DISCREPANCIES THE
CONTRACTOR SHALL CONTACT THE
ENGINEER.
2.ALL DISTURBED AREAS SHALL BE
REVEGETATED.
3.EROSION CONTROL PRACTICES, SITE
PROTECTION, AND REVEGETATION
METHODS SHALL FOLLOW CITY
REGULATIONS.
4.IN ADDITION TO THE EROSION CONTROL
MEASURES SHOWN ON THIS DRAWING, THE
CONTRACTOR SHALL COMPLETE,
COORDINATE WITH, AND UPDATE AS
REQUIRED, THE STORMWATER POLLUTION
PREVENTION PLAN (SWPP) FOR THIS
PROJECT.
5.CONTRACTOR TO TERRACE SLOPES USING
A "TRACKED" VEHICLE, RUN
PERPENDICULAR TO SLOPE TO INHIBIT
RILL/GULLEY EROSION, CONTRACTOR MAY
USE OTHER WINDROW-TYPE METHODS AS
APPROVED BY ENGINEER. TYPICAL ALL
SLOPES, REPEAT AS NECESSARY UNTIL
LANDSCAPING IS INSTALLED.
6.ANY AREAS USED FOR STOCKPILING
AND/OR STAGING SHOULD ALSO HAVE
SEDIMENT AND EROSION CONTROL
MEASURES AS NECESSARY. THESE AREAS
SHOULD BE LOCATED AT LEAST 100' AWAY
FROM DRAINAGE WAYS. THE SWMP
SHOULD BE UPDATED TO SHOW THESE
AREAS AND SEDIMENT AND EROSION
CONTROL ITEMS. THE ITEMS MAY INCLUDE
BUT ARE NOT LIMITED TO VEHICLE
TRACKING CONTROL, SILT FENCE,
CONSTRUCTION FENCE, CONCRETE
WASHOUT, AND SEDIMENT TRAP.
7.TEMPORARY SEEDING OR TACKIFER
PLACEMENT SHALL BE UTILIZED IN THE
EVENT THAT A GRADED AREA IS EXPOSED
LONGER THAN 14 DAYS WITH NO
CONSTRUCTION ACTIVITY.
8.TURF REINFORCEMENT MAT SHALL BE
PYRAMAT OR APPROVED EQUAL.
9.CONTRACTOR SHALL REMOVE ALL
SEDIMENT, MUD, CONSTRUCTION DEBRIS,
OR OTHER POTENTIAL POLLUTANTS THAT
MAY HAVE BEEN DISCHARGED TO OR,
ACCUMULATE IN, THE FLOW LINES AND
PUBLIC RIGHTS-OF-WAY OF THE CITY, AS A
RESULT OF CONSTRUCTION ACTIVITIES
ASSOCIATED WITH THIS DEVELOPMENT OR
CONSTRUCTION PROJECT. SAID REMOVAL
SHALL BE CONDUCTED DAILY, AS MAY BE
REQUIRED. SUCH MATERIALS SHALL BE
PREVENTED FROM ENTERING THE STORM
SEWER.
10.THE PROJECT LANDSCAPE PLAN WILL
CONTAIN THE DETAILED INFORMATION
REGARDING REQUIRED SEED TYPES/MIXES.
11.SEE THE GENERAL NOTES SHEETS FOR ALL
OF THE CITY OF FORT COLLINS EROSION
CONTROL NOTES.
VTC
WD
TS
IP
TRM
SF
LIMITS OF DISTURBANCE
RIP RAP
FLOW DIRECTION
SF
SRSR
CWA
PSPS
A
B
BBBB
B B
B
B
PHASE 1
Implementation Timeline: Paving to Final Restoration
BBB
B B
B
B
B
01 02
03
04
05
06
07
08
EX_SITEOS-1
OS-2
OS-3
OS-4
OS-5
2
3
4
5
6
7
34
38
GT-1
GT-11
GT-2
GT-3
GT-4GT-5
GT-6 GT-7
STM_A1
STM_A-1-1
STM_A-1-2
STM_A-1-3
STM_A2
STM_A-2-1
STM_B1
STM_C1
STM_C2
INLET_A1-3
INLET_A1-4
INLET_A3-1
INLET_B-1
INLET_C1
INLET_C3
1
1
2
4
6
7
8
13
17
49
51
J-GT-INLET-A1-3
J-GT-INLET-A1-4
J-GT-INLET-A3-1
J-GT-INLET-B-1
J-GT-INLET-C-1
J-GT-INLET-C-3
J-INLET-A1-3
J-INLET-A1-4
J-INLET-A3-1
J-INLET-B-1
J-INLET-C-1
J-INLET-C-3
SDMH_A1-1
SDMH_A-2SDMH_A-4
OUT-POND
OUT-EAST
OUT-SW
DP-SITE
BLOOM_POND
Gage1
Subcatch
Area
25.00
50.00
75.00
100.00
ac
Node
Invert
25.00
50.00
75.00
100.00
ft
Link
Max Flow
5.00
10.00
15.00
20.00
CFS
12/16/2022 00:01:00
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 1
PROJECT Bloom Multi-Family
SWMM Catchment Parameter Woksheet
Enter Computed Use
Enter Enter Channel X Z K y W W
Basin Basin Area Flow Path SHAPE SHAPE SHAPE SHAPE FROM Rounded Average %
ID Acres L FACTOR FACTOR FACTOR FACTOR SHAPE Up By Slope %Imperv
(ft)FACTOR 25
1 1.850 377 0.56714 0.70 4.0 0.96354 363.3 375 2.8 85.00
2 1.323 406 0.34974 0.60 4.0 0.68801 279.3 300 3.0 86.00
3 1.957 540 0.29232 0.60 4.0 0.57937 312.9 325 3.7 84.00
4 1.397 300 0.67592 0.70 4.0 1.13154 339.5 350 3.2 82.00
5 1.030 300 0.49857 0.70 4.0 0.85485 256.5 275 3.4 75.00
6 0.363 170 0.54760 0.50 4.0 1.16598 198.2 200 3.5 51.00
7 1.685 350 0.59911 0.70 4.0 1.01347 354.7 375 2.7 92.00
8 2.446 350 0.86986 0.60 4.0 1.59486 558.2 575 11.2 23.00
OS-1 0.840 395 0.23449 0.80 4.0 0.36419 143.9 150 4.9 58.00
OS-2 0.449 355 0.15511 0.80 4.0 0.24337 86.4 100 2.8 41.00
OS-3 0.956 725 0.07922 0.80 4.0 0.12549 91.0 100 5.7 54.00
OS-4 0.852 350 0.30301 0.80 4.0 0.46646 163.3 175 5.1 68.00
OS-5 0.641 340 0.24170 0.80 4.0 0.37503 127.5 150 6.0 62.00
OS-6 0.709 730 0.05796 0.80 4.0 0.09206 67.2 75 3.1 42.00
OS-7 0.754 350 0.26800 0.80 4.0 0.41444 145.1 150 2.6 32.00
OS-8 0.469 292 0.23971 0.80 4.0 0.37204 108.6 125 1.8 69.00
OS-9 1.268 900 0.06821 0.80 4.0 0.10821 97.4 100 3.1 79.00
OS-10 0.118 340 0.04439 0.80 4.0 0.07064 24.0 25 2.5 31.00
EX-Site 15.830 1550 0.28702 0.60 4.0 0.56925 882.3 900 1.0 2.00
TOTAL - DEV 13.98
TOTAL - EX 1.85
OS-6-10 3.318
For Existing Conditions used Poor Grass Cover on Rough
For Developed Conditions used Average Grass Cover
EPA STORM WATER MANAGEMENT MODEL - VERSION 5.2 (Build 5.2.3)
------------------------------------------------------------
BLOOM MULTI-FAMILY DEVELOPMENT
EPA SWMM Version 5.2.3 Last Updated 6/4/2023
*************
Element Count
*************
Number of rain gages ...... 1
Number of subcatchments ... 14
Number of nodes ........... 30
Number of links ........... 32
Number of pollutants ...... 0
Number of land uses ....... 0
****************
Raingage Summary
****************
Data Recording
Name Data Source Type Interval
------------------------------------------------------------------------
Gage1 100year INTENSITY 5 min.
********************
Subcatchment Summary
********************
Name Area Width %Imperv %Slope Rain Gage Outlet
-----------------------------------------------------------------------------------------------------------
01 1.85 375.00 85.00 2.8000 Gage1 1
02 1.32 300.00 86.00 3.7000 Gage1 49
03 1.96 325.00 84.00 3.7000 Gage1 J-GT-INLET-C-1
04 1.40 350.00 82.00 3.2000 Gage1 51
05 1.03 275.00 75.00 3.4000 Gage1 J-GT-INLET-B-1
06 0.36 200.00 51.00 3.5000 Gage1 17
07 1.69 375.00 92.00 2.7000 Gage1 J-GT-INLET-A3-1
08 2.45 575.00 23.00 11.2000 Gage1 BLOOM_POND
EX_SITE 15.83 550.00 2.00 0.7000 Gage1 DP-SITE
OS-1 0.84 150.00 40.00 4.9000 Gage1 4
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 1
OS-2 0.45 100.00 41.00 2.8000 Gage1 2
OS-3 0.96 100.00 54.00 5.7000 Gage1 OUT-EAST
OS-4 0.85 175.00 68.00 5.1000 Gage1 8
OS-5 0.64 150.00 62.00 6.0000 Gage1 OUT-SW
************
Node Summary
************
Invert Max. Ponded External
Name Type Elev. Depth Area Inflow
-------------------------------------------------------------------------------
1 JUNCTION 4944.04 20.00 0.0
2 JUNCTION 4944.00 20.00 0.0
4 JUNCTION 4940.50 20.00 0.0
6 JUNCTION 4942.09 20.00 0.0
7 JUNCTION 4938.53 20.00 0.0
8 JUNCTION 4938.50 20.00 0.0
13 JUNCTION 4940.50 20.00 0.0
17 JUNCTION 4937.71 20.00 0.0
49 JUNCTION 4944.41 20.00 0.0
51 JUNCTION 4941.75 20.00 0.0
J-GT-INLET-A1-3 JUNCTION 4941.54 20.00 0.0
J-GT-INLET-A1-4 JUNCTION 4943.57 20.00 0.0
J-GT-INLET-A3-1 JUNCTION 4937.99 20.00 0.0
J-GT-INLET-B-1 JUNCTION 4938.18 20.00 0.0
J-GT-INLET-C-1 JUNCTION 4939.71 20.00 0.0
J-GT-INLET-C-3 JUNCTION 4943.32 20.00 0.0
J-INLET-A1-3 JUNCTION 4936.32 20.00 0.0
J-INLET-A1-4 JUNCTION 4938.39 20.00 0.0
J-INLET-A3-1 JUNCTION 4933.06 20.00 0.0
J-INLET-B-1 JUNCTION 4933.48 20.00 0.0
J-INLET-C-1 JUNCTION 4934.65 20.00 0.0
J-INLET-C-3 JUNCTION 4937.63 20.00 0.0
SDMH_A1-1 JUNCTION 4932.46 20.00 0.0
SDMH_A-2 JUNCTION 4931.51 20.00 0.0
SDMH_A-4 JUNCTION 4932.40 20.00 0.0
OUT-POND OUTFALL 4927.00 1.50 0.0
OUT-EAST OUTFALL 4940.00 1.00 0.0
OUT-SW OUTFALL 4936.00 2.00 0.0
DP-SITE OUTFALL 0.00 0.00 0.0
BLOOM_POND STORAGE 4928.40 10.00 0.0
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 2
************
Link Summary
************
Name From Node To Node Type Length %Slope Roughness
---------------------------------------------------------------------------------------------
2 4 8 CONDUIT 500.0 0.4000 0.0160
3 J-GT-INLET-A3-1 J-GT-INLET-B-1 CONDUIT 320.0 -0.0594 0.0160
4 8 OUT-SW CONDUIT 700.0 0.3571 0.0160
5 2 OUT-EAST CONDUIT 560.0 0.7143 0.0160
6 1 J-GT-INLET-A1-4 CONDUIT 80.0 0.5875 0.0160
7 J-GT-INLET-A1-4 51 CONDUIT 276.0 0.6594 0.0160
34 17 BLOOM_POND CONDUIT 50.0 4.6330 0.0200
38 BLOOM_POND OUT-POND CONDUIT 40.0 13.6247 0.0120
GT-1 49 J-GT-INLET-C-3 CONDUIT 141.0 0.7731 0.0160
GT-11 7 J-GT-INLET-B-1 CONDUIT 120.0 0.2908 0.0160
GT-2 J-GT-INLET-C-3 6 CONDUIT 50.0 2.4668 0.0160
GT-3 6 J-GT-INLET-C-1 CONDUIT 250.0 0.9508 0.0160
GT-4 J-GT-INLET-C-1 7 CONDUIT 150.0 0.7874 0.0160
GT-5 51 J-GT-INLET-A1-3 CONDUIT 20.0 1.0401 0.0160
GT-6 J-GT-INLET-A1-3 13 CONDUIT 54.0 1.9281 0.0160
GT-7 13 7 CONDUIT 185.0 1.0660 0.0160
STM_A1 SDMH_A-2 BLOOM_POND CONDUIT 65.0 0.6323 0.0120
STM_A-1-1 SDMH_A1-1 SDMH_A-4 CONDUIT 12.0 0.5000 0.0120
STM_A-1-2 J-INLET-A1-3 SDMH_A1-1 CONDUIT 330.0 1.1698 0.0120
STM_A-1-3 J-INLET-A1-4 J-INLET-A1-3 CONDUIT 276.0 0.7500 0.0120
STM_A2 SDMH_A-4 SDMH_A-2 CONDUIT 180.0 0.4939 0.0120
STM_A-2-1 J-INLET-A3-1 SDMH_A-4 CONDUIT 142.0 0.4648 0.0120
STM_B1 J-INLET-B-1 SDMH_A1-1 CONDUIT 204.0 0.5000 0.0120
STM_C1 J-INLET-C-1 J-INLET-B-1 CONDUIT 234.0 0.5000 0.0120
STM_C2 J-INLET-C-3 J-INLET-C-1 CONDUIT 320.0 0.9313 0.0120
INLET_A1-3 J-GT-INLET-A1-3 J-INLET-A1-3 ORIFICE
INLET_A1-4 J-GT-INLET-A1-4 J-INLET-A1-4 ORIFICE
INLET_A3-1 J-GT-INLET-A3-1 J-INLET-A3-1 ORIFICE
INLET_B-1 J-GT-INLET-B-1 J-INLET-B-1 ORIFICE
INLET_C1 J-GT-INLET-C-1 J-INLET-C-1 ORIFICE
INLET_C3 J-GT-INLET-C-3 J-INLET-C-3 ORIFICE
1 J-GT-INLET-B-1 BLOOM_POND WEIR
*********************
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 3
Cross Section Summary
*********************
Full Full Hyd. Max. No. of Full
Conduit Shape Depth Area Rad. Width Barrels Flow
---------------------------------------------------------------------------------------
2 TRAPEZOIDAL 1.00 21.50 0.51 42.00 1 80.27
3 TRAPEZOIDAL 2.00 84.00 1.02 82.00 1 193.02
4 TRAPEZOIDAL 2.00 84.00 1.00 83.00 1 466.77
5 TRAPEZOIDAL 1.00 21.50 0.51 42.00 1 107.27
6 street_1 1.06 19.96 0.47 42.00 1 85.39
7 street_1 1.06 19.96 0.47 42.00 1 90.46
34 TRAPEZOIDAL 1.00 4.00 0.67 4.00 1 48.82
38 CIRCULAR 1.50 1.77 0.38 1.50 1 42.00
GT-1 street_1 1.06 19.96 0.47 42.00 1 97.95
GT-11 street_1 1.06 19.96 0.47 42.00 1 60.08
GT-2 street_1 1.06 19.96 0.47 42.00 1 174.96
GT-3 street_1 1.06 19.96 0.47 42.00 1 108.63
GT-4 street_1 1.06 19.96 0.47 42.00 1 98.85
GT-5 street_1 1.06 19.96 0.47 42.00 1 113.61
GT-6 street_1 1.06 19.96 0.47 42.00 1 154.69
GT-7 street_1 1.06 19.96 0.47 42.00 1 115.02
STM_A1 CIRCULAR 2.00 3.14 0.50 2.00 1 19.49
STM_A-1-1 CIRCULAR 2.00 3.14 0.50 2.00 1 17.33
STM_A-1-2 CIRCULAR 1.50 1.77 0.38 1.50 1 12.31
STM_A-1-3 CIRCULAR 1.50 1.77 0.38 1.50 1 9.86
STM_A2 CIRCULAR 2.00 3.14 0.50 2.00 1 17.22
STM_A-2-1 CIRCULAR 1.50 1.77 0.38 1.50 1 7.76
STM_B1 CIRCULAR 2.00 3.14 0.50 2.00 1 17.33
STM_C1 CIRCULAR 2.00 3.14 0.50 2.00 1 17.33
STM_C2 CIRCULAR 1.50 1.77 0.38 1.50 1 10.98
**************
Street Summary
**************
Street street_1
Area:
0.0001 0.0006 0.0013 0.0023 0.0035
0.0051 0.0069 0.0091 0.0123 0.0166
0.0221 0.0286 0.0363 0.0452 0.0551
0.0662 0.0784 0.0917 0.1062 0.1218
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 4
0.1385 0.1563 0.1753 0.1953 0.2166
0.2389 0.2622 0.2855 0.3089 0.3323
0.3556 0.3794 0.4043 0.4304 0.4575
0.4858 0.5152 0.5458 0.5774 0.6102
0.6441 0.6792 0.7153 0.7526 0.7910
0.8306 0.8712 0.9130 0.9560 1.0000
Hrad:
0.0209 0.0418 0.0628 0.0837 0.1046
0.1255 0.1465 0.1461 0.1403 0.1471
0.1596 0.1750 0.1923 0.2108 0.2300
0.2498 0.2700 0.2906 0.3114 0.3324
0.3535 0.3748 0.3962 0.4177 0.4392
0.4608 0.4954 0.5391 0.5826 0.6261
0.6695 0.6864 0.7000 0.7143 0.7293
0.7449 0.7610 0.7776 0.7946 0.8119
0.8296 0.8476 0.8659 0.8845 0.9032
0.9222 0.9414 0.9608 0.9803 1.0000
Width:
0.0063 0.0126 0.0189 0.0252 0.0315
0.0379 0.0442 0.0590 0.0843 0.1095
0.1348 0.1600 0.1852 0.2105 0.2357
0.2610 0.2862 0.3114 0.3367 0.3619
0.3871 0.4124 0.4376 0.4629 0.4881
0.5133 0.5238 0.5238 0.5238 0.5238
0.5238 0.5457 0.5710 0.5962 0.6214
0.6467 0.6719 0.6971 0.7224 0.7476
0.7729 0.7981 0.8233 0.8486 0.8738
0.8990 0.9243 0.9495 0.9748 1.0000
****************
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
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 5
Infiltration Method ...... HORTON
Flow Routing Method ...... DYNWAVE
Surcharge Method ......... EXTRAN
Starting Date ............ 12/16/2022 00:00:00
Ending Date .............. 12/16/2022 23:59:00
Antecedent Dry Days ...... 0.0
Report Time Step ......... 00:01:00
Wet Time Step ............ 00:01:00
Dry Time Step ............ 00:05:00
Routing Time Step ........ 1.00 sec
Variable Time Step ....... YES
Maximum Trials ........... 20
Number of Threads ........ 1
Head Tolerance ........... 0.005000 ft
*********************
Control Actions Taken
*********************
************************** Volume Depth
Runoff Quantity Continuity acre-feet inches
************************** --------- -------
Total Precipitation ...... 10.349 3.927
Evaporation Loss ......... 0.000 0.000
Infiltration Loss ........ 3.800 1.442
Surface Runoff ........... 6.461 2.452
Final Storage ............ 0.090 0.034
Continuity Error (%) ..... -0.024
************************** Volume Volume
Flow Routing Continuity acre-feet 10^6 gal
************************** --------- ---------
Dry Weather Inflow ....... 0.000 0.000
Wet Weather Inflow ....... 6.461 2.105
Groundwater Inflow ....... 0.000 0.000
RDII Inflow .............. 0.000 0.000
External Inflow .......... 0.000 0.000
External Outflow ......... 4.807 1.567
Flooding Loss ............ 0.000 0.000
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 6
Evaporation Loss ......... 0.000 0.000
Exfiltration Loss ........ 0.000 0.000
Initial Stored Volume .... 0.000 0.000
Final Stored Volume ...... 1.656 0.540
Continuity Error (%) ..... -0.039
***************************
Time-Step Critical Elements
***************************
None
********************************
Highest Flow Instability Indexes
********************************
All links are stable.
*********************************
Most Frequent Nonconverging Nodes
*********************************
Node OUT-POND (0.14%)
Node OUT-EAST (0.14%)
Node OUT-SW (0.14%)
Node DP-SITE (0.14%)
Node J-INLET-A3-1 (0.05%)
*************************
Routing Time Step Summary
*************************
Minimum Time Step : 0.29 sec
Average Time Step : 1.00 sec
Maximum Time Step : 1.00 sec
% of Time in Steady State : 0.00
Average Iterations per Step : 2.03
% of Steps Not Converging : 0.14
Time Step Frequencies :
1.000 - 0.871 sec : 99.23 %
0.871 - 0.758 sec : 0.11 %
0.758 - 0.660 sec : 0.12 %
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 7
0.660 - 0.574 sec : 0.11 %
0.574 - 0.500 sec : 0.43 %
***************************
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
------------------------------------------------------------------------------------------------------------------------------
01 3.93 0.00 0.00 0.20 3.64 0.39 3.64 0.18 14.53 0.927
02 3.93 0.00 0.00 0.19 3.66 0.36 3.66 0.13 11.03 0.931
03 3.93 0.00 0.00 0.22 3.63 0.41 3.63 0.19 15.11 0.924
04 3.93 0.00 0.00 0.24 3.60 0.46 3.60 0.14 11.65 0.918
05 3.93 0.00 0.00 0.34 3.51 0.64 3.51 0.10 8.63 0.895
06 3.93 0.00 0.00 0.67 3.21 1.26 3.21 0.03 3.21 0.818
07 3.93 0.00 0.00 0.11 3.73 0.21 3.73 0.17 13.55 0.950
08 3.93 0.00 0.00 1.11 0.88 2.76 2.80 0.19 18.85 0.713
EX_SITE 3.93 0.00 0.00 2.41 0.08 1.52 1.52 0.65 13.92 0.387
OS-1 3.93 0.00 0.00 0.90 1.53 2.22 2.99 0.07 5.96 0.761
OS-2 3.93 0.00 0.00 0.89 1.57 2.21 3.00 0.04 3.14 0.763
OS-3 3.93 0.00 0.00 0.74 2.07 2.10 3.14 0.08 6.21 0.799
OS-4 3.93 0.00 0.00 0.49 2.60 1.81 3.37 0.08 7.05 0.859
OS-5 3.93 0.00 0.00 0.57 2.37 2.11 3.30 0.06 5.41 0.840
******************
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
---------------------------------------------------------------------------------
1 JUNCTION 0.06 0.59 4944.63 0 00:40 0.59
2 JUNCTION 0.01 0.24 4944.24 0 00:41 0.24
4 JUNCTION 0.02 0.35 4940.85 0 00:41 0.35
6 JUNCTION 0.03 0.44 4942.52 0 00:41 0.44
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 8
7 JUNCTION 0.04 0.79 4939.32 0 00:42 0.79
8 JUNCTION 0.03 0.45 4938.95 0 00:43 0.45
13 JUNCTION 0.03 0.54 4941.04 0 00:41 0.54
17 JUNCTION 0.00 0.18 4937.89 0 00:40 0.18
49 JUNCTION 0.05 0.54 4944.95 0 00:40 0.54
51 JUNCTION 0.05 0.61 4942.36 0 00:40 0.61
J-GT-INLET-A1-3 JUNCTION 0.02 0.50 4942.04 0 00:40 0.50
J-GT-INLET-A1-4 JUNCTION 0.02 0.50 4944.07 0 00:40 0.50
J-GT-INLET-A3-1 JUNCTION 0.03 1.02 4939.01 0 00:40 1.02
J-GT-INLET-B-1 JUNCTION 0.02 0.81 4938.99 0 00:42 0.81
J-GT-INLET-C-1 JUNCTION 0.02 0.51 4940.22 0 00:41 0.51
J-GT-INLET-C-3 JUNCTION 0.02 0.38 4943.70 0 00:40 0.38
J-INLET-A1-3 JUNCTION 0.12 5.33 4941.65 0 00:33 5.11
J-INLET-A1-4 JUNCTION 0.08 4.65 4943.04 0 00:36 3.57
J-INLET-A3-1 JUNCTION 0.60 5.87 4938.93 0 00:40 5.87
J-INLET-B-1 JUNCTION 0.36 5.71 4939.19 0 00:42 5.71
J-INLET-C-1 JUNCTION 0.16 5.42 4940.07 0 00:41 5.42
J-INLET-C-3 JUNCTION 0.07 2.87 4940.50 0 00:40 2.83
SDMH_A1-1 JUNCTION 1.08 6.30 4938.76 0 00:41 6.30
SDMH_A-2 JUNCTION 1.91 3.69 4935.20 0 00:41 3.69
SDMH_A-4 JUNCTION 1.12 5.75 4938.15 0 00:41 5.75
OUT-POND OUTFALL 0.15 0.16 4927.16 0 00:50 0.16
OUT-EAST OUTFALL 0.01 0.24 4940.24 0 00:41 0.24
OUT-SW OUTFALL 0.03 0.45 4936.45 0 00:43 0.45
DP-SITE OUTFALL 0.00 0.00 0.00 0 00:00 0.00
BLOOM_POND STORAGE 4.87 5.83 4934.23 0 02:34 5.83
*******************
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
-------------------------------------------------------------------------------------------------
1 JUNCTION 14.53 14.53 0 00:40 0.183 0.183 -0.027
2 JUNCTION 3.14 3.14 0 00:40 0.0365 0.0365 -0.004
4 JUNCTION 5.96 5.96 0 00:40 0.0682 0.0682 -0.455
6 JUNCTION 0.00 7.25 0 00:40 0 0.0591 -0.018
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 9
7 JUNCTION 0.00 26.37 0 00:41 0 0.182 0.122
8 JUNCTION 7.05 12.01 0 00:40 0.0781 0.147 0.207
13 JUNCTION 0.00 15.37 0 00:40 0 0.115 -0.224
17 JUNCTION 3.21 3.21 0 00:40 0.0317 0.0317 -0.003
49 JUNCTION 11.03 11.03 0 00:40 0.131 0.131 -0.019
51 JUNCTION 11.65 20.40 0 00:40 0.137 0.212 -0.031
J-GT-INLET-A1-3 JUNCTION 0.00 20.10 0 00:40 0 0.212 -0.007
J-GT-INLET-A1-4 JUNCTION 0.00 14.49 0 00:40 0 0.183 0.065
J-GT-INLET-A3-1 JUNCTION 13.55 21.04 0 00:38 0.171 0.203 0.394
J-GT-INLET-B-1 JUNCTION 8.63 41.95 0 00:41 0.0983 0.31 -0.167
J-GT-INLET-C-1 JUNCTION 15.11 21.63 0 00:40 0.193 0.252 -0.066
J-GT-INLET-C-3 JUNCTION 0.00 10.90 0 00:40 0 0.131 0.006
J-INLET-A1-3 JUNCTION 0.00 9.35 0 00:40 0 0.205 -0.129
J-INLET-A1-4 JUNCTION 0.00 4.60 0 00:40 0 0.107 -0.095
J-INLET-A3-1 JUNCTION 0.00 8.17 0 00:58 0 0.187 -0.055
J-INLET-B-1 JUNCTION 0.00 13.36 0 00:33 0 0.354 -0.046
J-INLET-C-1 JUNCTION 0.00 13.01 0 00:40 0 0.258 -0.099
J-INLET-C-3 JUNCTION 0.00 3.57 0 00:40 0 0.0722 -0.118
SDMH_A1-1 JUNCTION 0.00 18.51 0 00:42 0 0.544 0.033
SDMH_A-2 JUNCTION 0.00 25.42 0 00:41 0 0.731 0.290
SDMH_A-4 JUNCTION 0.00 25.42 0 00:41 0 0.731 0.002
OUT-POND OUTFALL 0.00 1.00 0 00:50 0 0.592 0.000
OUT-EAST OUTFALL 6.21 8.82 0 00:40 0.0815 0.118 0.000
OUT-SW OUTFALL 5.41 13.90 0 00:41 0.0574 0.204 0.000
DP-SITE OUTFALL 13.92 13.92 0 00:55 0.653 0.653 0.000
BLOOM_POND STORAGE 18.85 83.82 0 00:42 0.186 1.13 -0.016
**********************
Node Surcharge Summary
**********************
Surcharging occurs when water rises above the top of the highest conduit.
---------------------------------------------------------------------
Max. Height Min. Depth
Hours Above Crown Below Rim
Node Type Surcharged Feet Feet
---------------------------------------------------------------------
J-INLET-A1-3 JUNCTION 0.52 3.829 14.671
J-INLET-A1-4 JUNCTION 0.24 3.147 15.353
J-INLET-A3-1 JUNCTION 0.81 4.367 14.133
J-INLET-B-1 JUNCTION 0.69 3.709 14.291
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 10
J-INLET-C-1 JUNCTION 0.58 3.424 14.576
J-INLET-C-3 JUNCTION 0.30 1.372 17.128
SDMH_A1-1 JUNCTION 0.97 4.299 13.701
SDMH_A-2 JUNCTION 11.27 1.690 16.310
SDMH_A-4 JUNCTION 1.01 3.754 14.246
*********************
Node Flooding Summary
*********************
No nodes were flooded.
**********************
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
------------------------------------------------------------------------------------------------
BLOOM_POND 103.645 28.0 0.0 0.0 140.852 38.0 0 02:34 1.00
***********************
Outfall Loading Summary
***********************
-----------------------------------------------------------
Flow Avg Max Total
Freq Flow Flow Volume
Outfall Node Pcnt CFS CFS 10^6 gal
-----------------------------------------------------------
OUT-POND 96.65 0.95 1.00 0.592
OUT-EAST 21.39 0.86 8.82 0.118
OUT-SW 25.35 1.26 13.90 0.204
DP-SITE 17.27 6.02 13.92 0.653
-----------------------------------------------------------
System 40.16 9.09 33.54 1.566
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 11
*******************
Street Flow Summary
*******************
--------------------------------------------------------------------------------------------------------------------------------
Peak Avg. Bypass Back Peak
Peak Maximum Maximum Flow Flow Flow Flow Capture
Flow Spread Depth Inlet Inlet Inlet Capture Capture Freq Freq / Inlet
Street Conduit CFS ft ft Design Location Count Pcnt Pcnt Pcnt Pcnt CFS
--------------------------------------------------------------------------------------------------------------------------------
6 14.488 21.104 0.542
7 9.226 21.641 0.555
GT-1 10.898 17.087 0.462
GT-11 24.755 22.000 0.800
GT-2 7.248 14.468 0.409
GT-3 6.998 17.759 0.475
GT-4 11.224 22.000 0.649
GT-5 20.097 21.653 0.556
GT-6 15.372 19.888 0.518
GT-7 15.147 22.000 0.660
********************
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
-----------------------------------------------------------------------------
2 CONDUIT 5.31 0 00:41 1.50 0.07 0.40
3 CONDUIT 9.26 0 00:38 1.01 0.05 0.45
4 CONDUIT 9.95 0 00:43 2.12 0.02 0.23
5 CONDUIT 2.82 0 00:41 2.00 0.03 0.24
6 CONDUIT 14.49 0 00:40 3.17 0.17 0.51
7 CONDUIT 9.23 0 00:40 1.90 0.10 0.52
34 CONDUIT 3.19 0 00:40 4.54 0.07 0.18
38 CONDUIT 1.00 0 00:50 9.90 0.02 0.55
GT-1 CONDUIT 10.90 0 00:40 3.58 0.11 0.44
GT-11 CONDUIT 24.75 0 00:42 2.88 0.41 0.75
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 12
GT-2 CONDUIT 7.25 0 00:40 3.30 0.04 0.39
GT-3 CONDUIT 7.00 0 00:41 2.16 0.06 0.45
GT-4 CONDUIT 11.22 0 00:41 1.70 0.11 0.61
GT-5 CONDUIT 20.10 0 00:40 4.13 0.18 0.52
GT-6 CONDUIT 15.37 0 00:40 3.79 0.10 0.49
GT-7 CONDUIT 15.15 0 00:41 2.21 0.13 0.62
STM_A1 CONDUIT 25.42 0 00:41 8.28 1.30 1.00
STM_A-1-1 CONDUIT 18.51 0 00:42 5.89 1.07 1.00
STM_A-1-2 CONDUIT 9.35 0 00:40 5.29 0.76 1.00
STM_A-1-3 CONDUIT 4.60 0 00:40 3.90 0.47 1.00
STM_A2 CONDUIT 25.42 0 00:41 8.09 1.48 1.00
STM_A-2-1 CONDUIT 8.14 0 00:58 4.61 1.05 1.00
STM_B1 CONDUIT 13.19 0 00:33 4.20 0.76 1.00
STM_C1 CONDUIT 13.00 0 00:40 4.14 0.75 1.00
STM_C2 CONDUIT 3.59 0 00:40 2.72 0.33 1.00
INLET_A1-3 ORIFICE 4.75 0 00:40
INLET_A1-4 ORIFICE 4.60 0 00:40
INLET_A3-1 ORIFICE 8.17 0 00:58 1.00
INLET_B-1 ORIFICE 6.39 0 00:33
INLET_C1 ORIFICE 9.46 0 00:40 1.00
INLET_C3 ORIFICE 3.57 0 00:40
1 WEIR 40.68 0 00:42 0.16
***************************
Flow Classification Summary
***************************
-------------------------------------------------------------------------------------
Adjusted ---------- Fraction of Time in Flow Class ----------
/Actual Up Down Sub Sup Up Down Norm Inlet
Conduit Length Dry Dry Dry Crit Crit Crit Crit Ltd Ctrl
-------------------------------------------------------------------------------------
2 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.99 0.00
3 1.00 0.00 0.19 0.00 0.80 0.00 0.00 0.00 0.97 0.00
4 1.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.98 0.00
5 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.95 0.00
6 1.00 0.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.00
7 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.99 0.00
34 1.00 0.63 0.00 0.00 0.00 0.00 0.00 0.37 0.00 0.00
38 1.00 0.03 0.00 0.00 0.69 0.28 0.00 0.00 0.00 0.00
GT-1 1.00 0.00 0.00 0.00 0.01 0.99 0.00 0.00 0.00 0.00
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 13
GT-11 1.00 0.00 0.01 0.00 0.70 0.29 0.00 0.00 0.01 0.00
GT-2 1.00 0.01 0.00 0.00 0.91 0.08 0.00 0.00 0.99 0.00
GT-3 1.00 0.00 0.01 0.00 0.79 0.20 0.00 0.00 0.77 0.00
GT-4 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.99 0.00
GT-5 1.00 0.00 0.00 0.00 0.03 0.97 0.00 0.00 0.00 0.00
GT-6 1.00 0.01 0.01 0.00 0.89 0.09 0.00 0.00 0.98 0.00
GT-7 1.00 0.01 0.00 0.00 0.99 0.00 0.00 0.00 0.98 0.00
STM_A1 1.00 0.01 0.00 0.00 0.96 0.00 0.00 0.03 0.00 0.00
STM_A-1-1 1.00 0.01 0.00 0.00 0.99 0.00 0.00 0.00 0.00 0.00
STM_A-1-2 1.00 0.01 0.00 0.00 0.99 0.00 0.00 0.00 0.96 0.00
STM_A-1-3 1.00 0.01 0.00 0.00 0.90 0.10 0.00 0.00 0.95 0.00
STM_A2 1.00 0.01 0.00 0.00 0.99 0.00 0.00 0.00 0.00 0.00
STM_A-2-1 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.31 0.00
STM_B1 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.51 0.00
STM_C1 1.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.96 0.00
STM_C2 1.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.96 0.00
*************************
Conduit Surcharge Summary
*************************
----------------------------------------------------------------------------
Hours Hours
--------- Hours Full -------- Above Full Capacity
Conduit Both Ends Upstream Dnstream Normal Flow Limited
----------------------------------------------------------------------------
38 0.01 5.49 0.01 0.01 0.01
STM_A1 10.73 11.27 15.31 0.57 0.26
STM_A-1-1 0.92 0.97 1.01 0.21 0.86
STM_A-1-2 0.52 0.52 6.03 0.01 0.01
STM_A-1-3 0.24 0.24 0.52 0.01 0.01
STM_A2 1.01 1.01 11.27 0.62 0.71
STM_A-2-1 0.81 0.81 6.74 0.21 0.51
STM_B1 0.69 0.69 0.97 0.01 0.01
STM_C1 0.58 0.58 0.69 0.01 0.01
STM_C2 0.30 0.30 0.63 0.01 0.01
Analysis begun on: Tue Jun 6 12:13:25 2023
Analysis ended on: Tue Jun 6 12:13:26 2023
Total elapsed time: 00:00:01
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 14
BLOOM MULTI-FAMILY DEVELOPMENT
100-Year Page 15
Project: Disturbed Acres:3.72
EROSION CONTROL BMPs Units
Estimated
Quantity
Unit
Price
Total
Price
L.F. 850 $2.50 $2,125.00
EA 2 $750.00 $1,500.00
EA 1 $1,500.00 $1,500.00
EA 1 $5,000.00 $5,000.00
L.F. 70 $10.00 $700.00
E.A 7 $200.00 $1,400.00
A.C 0.5 $6,000.00 $3,000.00
Sub-Total: $15,225.00
1.5 x Sub-Total: $22,837.50
Amount of security: $22,837.50
Total Acres x Price/acre: $5,580.00
$1,500.00 Sub-Total: $5,580.00
1.5 x Sub-Total: $8,370.00
Amount to Re-seed: $8,370.00
Minimum escrow amount: $3,000.00
Erosion Control Escrow:$22,837.50
Unit Price of Seeding per acre:
Miniumum Escrow Amount
Final Escrow Amount
“The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times
the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid,
whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three
thousand dollars ($3,000) for commercial development”
Rock Sock (rs)
Vehicle Tracking Control (VTC)
Straw WattLe (WD)
Surface Roughening (SR)
Reseeding Amount
Erosion and Sediment Control Escrow/Security Calculation
for The City of Fort Collins
Bloom Multi-Family Development - Phase 2
BMP Amount
Silt Fence (SF)
Inlet Protection (IP)
Concrete Washout (CW)
6/6/2023 4:08 PMD:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\Appendices\APPENDIX B - BLOOM EROSION CONTROL ESCROW.pdf.xls
Project: Disturbed Acres:12.78
EROSION CONTROL BMPs Units
Estimated
Quantity
Unit
Price
Total
Price
L.F. 3450 $2.50 $8,625.00
EA 5 $750.00 $3,750.00
EA 1 $1,500.00 $1,500.00
EA 1 $5,000.00 $5,000.00
L.F. 350 $10.00 $3,500.00
E.A 35 $200.00 $7,000.00
A.C 2 $6,000.00 $12,000.00
Sub-Total: $41,375.00
1.5 x Sub-Total: $62,062.50
Amount of security: $62,062.50
Total Acres x Price/acre: $19,170.00
$1,500.00 Sub-Total: $19,170.00
1.5 x Sub-Total: $28,755.00
Amount to Re-seed: $28,755.00
Minimum escrow amount: $3,000.00
Erosion Control Escrow:$62,062.50
Erosion and Sediment Control Escrow/Security Calculation
for The City of Fort Collins
BMP Amount
Silt Fence (SF)
Vehicle Tracking Control (VTC)
Straw Wattle (WD)
Reseeding Amount
Rock Sock (rs)
Miniumum Escrow Amount
Bloom Multi-Family Development - Phase 1
Unit Price of Seeding per acre:
“The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times
the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid,
whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three
thousand dollars ($3,000) for commercial development”
Inlet Protection (IP)
Concrete Washout (CW)
Surface Roughening (SR)
Final Escrow Amount
6/6/2023 4:08 PMD:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\Appendices\APPENDIX B - BLOOM EROSION CONTROL ESCROW.pdf.xls
Preliminary Drainage and Erosion Control Report
Bloom Multi Family Development
Fort Collins, CO
2
APPENDIX B
WATER QUALITY AND LID CALCULATIONS
100-YEAR SWMM MODEL REPORT
Runoff Coefficients and % Impervious for Chamber System
Roof (1)Asphalt Walks(1)Gravel(1)Lawns(1)
%I = 90% %I = 100% %I = 90% %I =40% %I=2%
acres sf sf sf sf sf sf
C2 C5 C10 C25 C50 C100
0.0 0 - - - - - - -
0.0 0 0 0 0 0 0 -- - - - - -
Proposed Site to Chambers WQ Chambers
12.1 524976 85980 233600 66225 0 139171 71.1% C/D 0.764 0.764 0.764 0.956 0.956 0.956
0 - - - - - - -
Onsite Total 12.1 524976 85980 233600 66225 0 139171 71%0.764 0.764 0.764 0.956 0.956 0.956
Notes:
(1) Recommended % Imperviousness Values from USDCM Vol 1 - Ch 5 - Table RO-3. Increased Lawns from 0% to 2% Impervious.
(2) Runoff C is based on %I, UDFCD Eq RO-7 and correction factors in Table RO-4.
(3) Impervious area assumed to be 2500 s.f. of roof and 500 s.f. of driveway per single family and twin home lot.
Proposed Basins
Existing Basins
Onsite Total
Basin
Areas
Composite
Imperviousness
(%I)
Total TotalDesign Pt.Composite Runoff Coefficients (2)NRCS Soil
Type
Calculations by: KWH
Date: 6/6/2023 D:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\C22026 - Bloom WQ Chamber Sizing.xlsm
TIME OF CONCENTRATION FOR CHAMBER SYSTEM FLOWS
Area Length Slope ti
(2)Length Slope Velocity (3)tt
(4)Check tc?Total
Length tc
(5)
acres ft % min ft % fps min min Urban? ft min min
Existing Basins 0.00 0.0 - - - - - - - -
0.0 - - - - - - - -
Proposed Site to Chambers WQ Chambers 12.1 Paved 0.90 115 2 3.1 1126 0.85 20 1.8 10.2 13.2 Yes 1241 17 13
Notes:
(1) C5 based initial ground type and Table RO-5 (4)tt=L/(V*60 sec/min)
(2)ti = [1.8(1.1-C5)L1/2]/S1/3, S= slope in %, L=length of overland flow (400' max)(5)tc check (for urban or developed areas only) = total length/180 + 10
(3)V=CvS0.5, S=watercourse slope in ft/ft, UDFCD Equation RO-4 (6)min tc = 5 min
Proposed Basins
Basin Design Pt.
Initial Overland Flow Time (ti)Travel/Channelized Time of Flow (tt)
ti+tt
tc Check for Urbanized Basins
Final tc
(6)Initial
Ground
Type
C5
(1)Cv
0
Water Quality Required for Chamber System
Area (acres)Area Watershed WQCV* (cf)
(sf) (acres) (inches) (Extended Detention)
Proposed
Site 524,976 12.052 71%0.28 14,709
---
14,709Total
* based on 40 hr storage and additional 20% for extended detention
Basin %I
Required Onsite Water Quality Capture Volume
Calculations by: bao
Date: 1/6/2023 D:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\C22026 - Bloom WQ Chamber Sizing.xlsm
1/2 OF THE 2-YEAR STORM TO CHAMBER SYSTEM
Final Runoff Coefficients Rainfall Intensity Peak Discharge
tc
(6)I Q
acre min in/hr cfs
Proposed Site to
Chambers WQ Chambers 12.1 13 0.764 1.04 9.60
9.60Totals
Proposed Basins
Design Pt.AreaBasin
C
Calculations by: BAO
Date: 1/6/2023 D:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\C22026 - Bloom WQ Chamber Sizing.xlsm
Volume to Chambers
(FAA Method)
100 year storm into detention facility
Area (sf) Area (acres)C2
524976 12.052 0.76
Release rate out of chamber system
Qout (cfs) cfs/acre Tc (min)
10.791
Rainfall
Intensity
Inflow
Volume
Adjustment
Factor
Average Outflow
Rate Outflow Volume Required
Storage Volume
I Vi=(Qin*T*60)m= 0.5(1 +
Tc/T)Qav = m*Qout Vo=Qav*T *60 Vs=Vi-Vo
min in/hr cfs
ft 3 cfs ft 3 ft 3
5 1.43 13.1 3,938 0.50 5.40 1,619 2,320
10 1.11 10.2 6,108 0.50 5.40 3,237 2,871
15 0.94 8.6 7,753 0.50 5.40 4,856 2,897
20 0.81 7.4 8,900 0.50 5.40 6,475 2,425
25 0.72 6.6 9,881 0.50 5.40 8,093 1,787
30 0.65 6.0 10,779 0.50 5.40 9,712 1,067
35 0.60 5.5 11,511 0.50 5.40 11,331 181
40 0.54 4.9 11,829 0.50 5.40 12,949 -1,120
45 0.50 4.6 12,313 0.50 5.40 14,568 -2,255
50 0.46 4.2 12,714 0.50 5.40 16,187 -3,473
55 0.44 4.0 13,225 0.50 5.40 17,805 -4,580
60 0.41 3.8 13,598 0.50 5.40 19,424 -5,826
70 0.37 3.4 14,123 0.50 5.40 22,661 -8,538
80 0.33 3.0 14,593 0.50 5.40 25,898 -11,305
90 0.31 2.8 15,173 0.50 5.40 29,136 -13,962
100 0.28 2.6 15,477 0.50 5.40 32,373 -16,896
110 0.26 2.4 15,809 0.50 5.40 35,610 -19,801
120 0.25 2.3 16,251 0.50 5.40 38,848 -22,596
Max Volume, ft 3 =2,897
= 0.066
acre-ft
Comments
Required Detention Volume
Rainfall
Duration (T)
Qin=
∑C100*Area*I
Comments
RELEASE RATE OUT OF CHAMBER
Calculations by: ARS
Date: 10/3/2019
D:\Civilworx\CivilWorx Dropbox\CivilWorx\Projects\2022\C22026 - Bloom Multi Family\06_Design\Reports\Drainage\C22026 - Bloom WQ Chamber
Sizing.xlsm
VAULT ID
TOTAL
REQUIRED WQ
VOLUME (CF)
WQ
FLOW
(CFS)
CHAMBER TYPE
CHAMBER
RELEASE RATE
(CFS)
CHAMBER
VOLUME (CF)
INSTALLED CHAMBER
W/AGGREGATE (CF)
MIN. # OF
CHAMBERS
TOTAL
RELEASE
RATE (CFS)
REQUIRED
STORAGE
VOLUME BY FAA
METHOD (CF)
MIN # OF
CHAMBERS
STORAGE
PROVIDED
WITHIN THE
CHAMBERS (CF)
TOTAL
INSTALLED
SYSTEM
VOLUME (CF)
S1 14,709 9.60 SC-160 0.011 6.85 15 981 10.791 2,897 423 6719.85 14715
S2 14,709 9.60 SC-740 0.024 45.9 74.9 197 4.728 6,547 143 9042.3 14755.3
0
0
S5 14,709 9.60 SC-310 0.016 14.7 29.3 503 8.048 4,131 282 7394.1 14737.9
SC-160 0.011 6.85 15 0 0 0 0 0
CHAMBER DIMENSIONS SC-160 SC-310 SC-740
WIDTH [IN] 25 34 51
LENGTH [IN] 84.4 85.4 85.4
HEIGHT [IN] 12 16 30
FLOOR AREA [SF] 14.7 20.2 30.2
CHAMBER VOLUME [CF]6.9 14.7 45.9
CHAMBER/AGGREGATE VOLUME [CF]15 29.3 74.9
Chamber Configuration Summary
STORM TECH CHAMBER DATA