HomeMy WebLinkAboutDrainage Reports - 10/06/2006Cky of Ft car, Dp d
AGE INVESTIGAt �'
10-6 Aw-
- o d
SEDIMENT EROSION CONTROL REPORT
for
CAMPUS WEST REDEVELOPMENT
Located in the Southeast Quarter of Section 15,
Township 7 North, Range 69 West of the 6" P.M.
(1325 West Elizabeth Street)
CITY OF FORT COLLINS, LARIMER COUNTY.) COLORADO
Prepared for:
Kenney & Associates, LLC
209 East 4' Street
Loveland, Colorado 80537
Revised: August 2006
Project No. GRD - 524 - 05
Prepared by:
MESSNER Engineering, Inc.
150 East 29"' Street, Suite 270 Loveland, Colorado 80538-2765 Telephone: (970) 663-2221
' Engineering, Inc.
August 22, 2006
Project No. GRD - 524 - 05
' Mr. Glen Schlueter
City of Fort Collins
Stormwater Utility
' 700 Wood Street
Fort Collins, Colorado 80522-0580
' Re: Drainage Investigation and Sediment Erosion Control Report for the CAMPUS WEST
REDEVELOPMENT project, City of Fort Collins, Larimer County, Colorado
' Dear Mr. Schlueter:
' We are pleased to submit for your acceptance, this Drainage Investigation and Sediment Erosion
Control Report for the CAMPUS WEST REDEVELOPMENT project, to be located at 1325 - 1331
West Elizabeth Street, Fort Collins, Colorado. This investigation was based upon the proposed site
development plan; on -site observations; available topographic information and the City of Fort Collins
adopted Drainage Basin Master Plans and Flood Plains.
' The investigation and the recommendations within this report have been performed according to the
criteria established in the City of Fort Collins' "Storm Drainage Design Criteria and Construction
Standards."
We sincerely appreciate your time and consideration in the review of this project. If you should have
any questions, please feel free to contact this office.
Respectfully Submitted,
MESSNER Engineering, Inc.
Cameron W. Knapp, P. E.
I hereby state that the attached "Drainage Investigation and Sediment Erosion Control Report for
the CAMPUS WEST REDEVELOPMENT project, to be located in the Southeast Quarter of
Section 15, Township 7 North, Range 69 West of the O P.M., City of Fort Collins, Larimer
County, Colorado' was prepared by me or under my direct supervision in accordance with the
provisions of the City of Fort Collins' "Storm Drainage Design ept%w d li ggstruction Standards"
for the owners thereof.
Dennis R.
Registered
State of Cc
Civil Engineering Consultants 9l2G/Crp
150 E. 29th Street, Suite 270 Lovelaind, Colorado 80538 (970) 663-2221
TABLE OF CONTENTS
Description Page
LETTER OF TRANSMITTAL I
TABLE OF CONTENTS ii & iii
1. GENERAL LOCATION AND DESCRIPTION
A. Location 1
B. Description of Property 1
II. DRAINAGE BASINS & SUB -BASINS
A. Major Basin Description 2
B. Sub -basin Description 2
III. DRAINAGE DESIGN CRITERIA
A. Development Regulations 3
B. Development Criteria Reference and Constraints 3
C. Hydrologic Criteria 3
D. Hydraulic Criteria 4
IV. DRAINAGE FACILITY DESIGN
A. General Concept 5
B. Sub -basin Description 5
C. Canal Importation Floodplain 5
V. SEDIMENT EROSION CONTROL
A. General Concept 6
VI. STORMWATER QUALITY CONTROL
A. General Concept 7
B. Stormwater Quality BMPs 7
VII. CONCLUSIONS'
A. Compliance with Standards 8
B. Drainage Concept 8
VIII. REFERENCES 9
ii
TABLE OF CONTENTS (CONTINUED)
EXHIBITS
Vicinity Map
Canal Importation Floodplain - Plate 7
Existing Conditions Drainage Exhibit
Proposed Conditions Drainage Exhibit
Grading Plan
Drainage & Erosion. Control Plan
Storm Drain Plan & Profile'
Details
APPENDIX I
DRAINAGE CALCULATIONS
APPENDIX II
CHARTS, GRAPHS, FIGURES, AND DETAILS
iii
I. General Location and Description:
' A. Location
1. The Campus West Redevelopment project site is located in the Southeast Quarter of
' Section 15, Township 7 North, Range 69 West of the 6" P.M., Larimer County, Colorado.
2. The site is more specifically located at the southeast corner of West Elizabeth Street and
' City Park Avenue. Previous addresses for the businesses that were located on the site were
1325 and 1331 West Elizabeth Street. (Refer to the included vicinity map.)
' 3. The area surrounding the site is substantially developed. A restaurant, liquor store and
apartment complex are located on the opposite side of City Park Avenue to the west. The
rectory for the John =11 University Center is located on the property immediately south
' of the site. A car wash and the John MII University Center are located on the properties
to the east of the site. Restaurants, personal service shops and retail stores are located on
the opposite side of West Elizabeth Street to the north of the site.
' B. Description of Property
' 1. The site is a rectangular shaped parcel that is currently vacant.
' a. The subject area consists of approximately 2.06 acres.
b. The north -south dimensions of the property are approximately 275-feet and the
east -west dimensions are approximately 330-feet.
c. The structures and pavement associated with the businesses that were on the site
' have been demolished and removed. The surface of the site consists of bare earth
and pavement base course. A construction fence has been placed around the
perimeter of the site.
' 2. The "Soil Survey ofLarimer County Area, Colorado" prepared by the U.S. Department
of Agriculture, Soil Conservation Service, indicates that the surface soil consists of Ahvan
' Satanta loams.
a. Altvan Satanta loam is described as a nearly level soil found on terraces and high
' benches. It is a deep, well -drained soil that formed in mixed alluvial deposits. The
"Soil Survey" identifies the runoff potential as slow to medium and that the hazard
ofwind and water erosion as slight to moderate. This soil type is classified in the `B'
hydrologic group.
3. The site is considered to have relatively flat slopes ranging from 0.5% to 2%. The terrain
typically slopes in a southwest to northeast direction.
4. The proposed development of the property will involve the construction of a 2-story
' mixed residential and commercial building. The total building footprint area will be
approximately 21,862 square feet. The associated driveways, walks and parking is to
' consist of 55,884 square feet. Landscaped areas are to consist of 10,788 square feet.
Access to the site will be provided from a driveway entrance to be constructed at West
Elizabeth Street that enters the site near its northeast corner and from an existing driveway
' to be reconstructed on City Park Avenue that enters the site near its southwest comer.
II. Drainage Basins and Sub -basins:
A. Major Basin Description
1. The site does not lie within a F.E.M.A. designated 100-year floodplain or floodway. The
site is located within the City of Fort Collins designated Canal Importation F000dplain.
' (Refer to Plate 7 - "Elizabeth Street/Constitution Avenue Flow Path -100-Year F000dplain
Map - Fully Developed Conditions with Existing Facilities" in the Exhibits Section of this
report.)
' 2. The proposed development lies within the "CANAL IMPORTATION BASIN" per the
' City of Fort Collins Master Drainage Plan. The Canal Importation Basin is approximately
5 square miles in area. The Canal Importation Basin contains three major irrigation canals
that traverse the Basin from North to South. Storm water enters and exits the Basin
' through these canals.
a. The site is located on the downhill side East of the Larimer County Canal No. 2.
' The site is located approximately 1,100 feet west of Shields Street, the eastern limit
of the Basin. Runoff from the area flows in a west to east direction until being
routed through the Colorado State University campus.
B. Sub -basin Description
1. The historic drainage basin of the property is identified on the Existing Conditions
Drainage Exhibit as Sub -Basin W.
' a. Sub -Basin `A' comprises approximately 2.03 acres from the total area ofthe site.
The sub -basin drains overland in a southwest to northeast direction. The run off
from the site drains onto West Elizabeth Street. A 30-inch diameter reinforced
' concrete pipe storm drain is located along the south side of West Elizabeth Street.
Storm drain inlets are located at the northwest and northeast comers of the site.
Gutter flows are intercepted by the inlets and directed to the 30-inch storm drain.
The 30-inch storm drain directs the intercepted flow easterly along West Elizabeth
Street and across Shields Street to the Colorado State University campus. The 2-
year and 100-year peak runoff rates for the sub -basin are 6.56 c.fs. and 14.9 c.fs
I
' 2. The site does not receive significant offsite flows from the adjacent properties during
minor storm events. The site may be affected by excess flows generated during a major
' storm event.
3. Runoff is prevented from entering the site from other sources.
' a. Offsite flow is prevented from intruding onto the site from the west by the curb
and gutter along City Park Avenue.
tb. Offsite flow during normal storm events is prevented from intruding onto the site
from the north by the curb and gutter along West Elizabeth Street. Excess flow
' routed along West Elizabeth Street may enter the site during a major storm event.
c. The neighboring property to the east slopes east and north towards West
' Elizabeth Street.
d. The neighboring property to the south slopes east and south towards University
tAvenue.
' M. Drainage Design Criteria:
' A. Development Regulations
1. Design criteria from the current City ofFort Collins Storm Drainage Design Criteria and
' Construction Standards and the Urban Flood Control District, Urban Storm Drainage
Manuals Volumes I, Il, and III were utilized.
B. Development Criteria Reference and Constraints
1. The drainage pattern offite will be affected by the development of the site in that flow
will be concentrated and channelized. The development of this site will not produce any
more runoff than the amount that occurred during the sites use as a movie theater and gas
station. Therefore, offite storm water detention is not required.
2. The drainage impact of this site will not adversely affect existing streets or utilities.
3. No offsite drainage traverses through the site.
C. Hydrological Criteria
1. The Rainfall -Intensity -Duration curve for the City of Fort Collins was used in
conjunction with the Rational Method for determining peak flows at various concentration
points.
a. The worksheets used to determine the peak runoff rates, (see Drainage
3
Calculations in Appendix I of this report), come from the Urban Storm Drainage
Manual. The composite imperiousness of a sub -basin was first computed using the
worksheets labeled "Area -Weighting for Runoff Coefficient Calculation". The
following worksheets labeled "Calculation of a Peak Runoff Using Rational
Method" were used to determine the minor and major peak runoff rates. The time
of concentration used for the existing conditions was the computed Tc; however,
the lesser value of either the Computed Tc or the Regional Tc was used for the
proposed conditions.
b. Table RO-3 from the Urban Storm Drainage Criteria Manual was used for
recommended imperviousness values for various land cover.
c. The hydrological group `B' was used in the Urban Storm Drainage Criteria
Spreadsheets for the on -site soil.
2. The 10-year and 100-year storms were analyzed in the design of the storm water
management infrastructure in accordance with the City of Fort Collins Storm Drainage
Design Criteria and Construction Standards.
a. The minor storm interval is based on the 10-year return frequency and the major
storm interval is based on a 100-year return frequency.
3. A Water Quality Capture Volume (WQCV) was incorporated into the design.
D. Hydraulic Criteria
1. A stormwater quality structure was designed for the project based upon the requirements
found in Volume III of the Urban Storm Drainage Criteria Manual.
a. Sizing of structures are based on the design figures and spreadsheets provided
in Vohnne III of the Urban Storm Drainage Criteria Manual.
2. Proposed storm drain pipes onsite are designed using smooth interior wall High Density
Polyethylene (HDPE) pipe.
a. A Mannings `n' value of 0.013 is to be used for all storm pipe according to
Sec.4.4.2 of the City of Fort Collins Storm Drainage Design Criteria.
3. Proposed storm drain pipes within public right-of-way are designed using Reinforced
Concrete Pipe(RCP) pipe.
a. A Mannings `n' value of 0.015 is to be used for all storm pipe according to
Sec.4.4.2 of the City of Fort Collins Storm Drainage Design Criteria.
4. Recommended Channel Design Roughness Coefficients are per Table MD-1 of the
Urban Storm Drainage Criteria Manual Volume I.
4
' IV. Drainage Facility Design:
A. General Concept
1. During a rainfall event, stormwater will be channelized within the parking lot curb and
' gutters and routed to the northeast corner of the site where a storm water inlet will be
constructed. The inlet will intercept storm water and direct it to a Storm Water Quality
Control device, a buried `StormTech' system In the event that a major storm occurs, an
' overflow is provided to allow for the discharge to the 30-inch storm drain pipe located in
West Elizabeth Street.
' 2. The contents in the tables, charts, and figures presented in Appendix II, come from the
Urban Storm Drainage Criteria Manual and the City ofFort Collins Storm Drainage Design
Criteria and Construction Standards. This data and information was used in the drainage
' design calculations presented in Appendix I.
' B. Specific Details
1. Sub -Basin `A', as designated on the Proposed Conditions Drainage Exhibit, consists of
' 2.03 acres that makes up the property during Phase I of the development. The peak runoff
rate during the 2-year storm was calculated to be 5.20 c.fs. and the 100-year peak runoff
rate is 11.99 c.fs.
CANAL IMPORTATION FLOODPLAIN
' The proposed site redevelopment is to consist of the construction of a mixed use building
along with the driveways, parking and site landscaping. Most ofthe proposed construction
will occur within the Canal Importation Floodplain adjacent to the West Elizabeth Street
' floodway. No development is proposed within the floodway. The Base Flood Elevation for
the site varies from elevation 5031.0 at the east curb line of City Park Avenue to 5028.0 at
the proposed driveway entrance to the site from West Elizabeth Street.
The west side of the building is to be a two story mixed use building that will face City Park
Avenue. The ground floor level is to consist of restaurant and retail uses. The lowest floor
level is to be the restaurant and retail portion of this building. The floor level is to be a
minimum of 18 inches above the Base Flood Elevation. The southern portion of the
structure is to be stepped up an additional one foot. Therefore, with a BFE of 5031.0 at the
west side of the building, the lowest floor at the north end of the structure is to be 5032.5.
The foundation is to step up at the break point. The structure is to be slab on grade with no
open area below grade. The lowest floor elevation in the residential portion of the building
E
V.
t
is to be 5033.5.
The north side of the building facing West Elizabeth Street is to be a two story mixed use
building. The ground floor level is to consist of restaurant and retail uses. The floor level is
to be a minimum of 18 inches above the Base Flood Elevation. The structure is to be
stepped down at the changes in BFE elevation. Therefore, with a BFE of 5031.0 at the west
end of the building, the lowest floor at the west end of the structure is to be 5032.5. The
foundation is to step down as it extends to the east and have the lowest floor elevation at
the east end of the building with an elevation of 5031.5 and a BFE of 5028.0.
All HVAC equipment is to be either interior ceiling mounted or roof mounted equipment.
No air conditioning condenser units are to be ground mounted.
None of the structures or uses to be developed on the site are `critical facilities' as
designated by the City Floodplain Regulations.
A Floodplain Use Permit is to be required for each structure.
A FEMA Elevation Certification is to be submitted prior to the issuance of a Certificate of
Occupancy for any structure.
All uses and construction shall comply with Chapter 10 of the Fort Collins City Code.
Sediment Erosion Control:
A. General Concept
1. Temporary erosion control measures will be implemented during the construction ofthis
project to help prevent water borne sediment from being washed away from disturbed areas
and being deposited onto the adjacent street and properties. These measures will include:
a. Silt Fencing around the entire perimeter of the property with the exception of the
site construction entry located on City Park Avenue.
b. Curb Sock Inlet Filter at the proposed inlet structure on site.
c. Vehicle Tracking Control Pad to be located at the site construction entrance
located on City Park Avenue. Note that perimeter construction fencing is in place
to restrict access to the entrance located on City Park Avenue.
6
' 2. Long term erosion control measures will be implemented at the final stage of
construction for this project. These measures will include:
' a. Landscape plantings.
' b. Installation of landscape fabric and gravel mulch on areas disturbed by
construction activities and other areas that are not designated for landscape
plantings. Species type and application rates shall conform to the vegetative erosion
control measures recommend by the City of Fort Collins's Stormwater Department.
(A copy of these measures is included in Appendix H of this report.).
' c. Down spouts are to discharge onto concrete aprons and concrete chases are to
be installed through sidewalks.
' 3. Maintenance of all erosion control measures will remain the responsibility of the
developer until the completion of the project.
4. Certain measures shall be taken in the event that high winds produce blowing dust and
possible wind erosion.
' a. Water down open and disturbed areas with a water truck.
' b. Surface roughening for soils that are exposed during land disturbing activities.
c. Stabilizing open and disturbed areas as soon as possible.
t
VI. Stormwater Quality Control:
A. General Concept
' 1. Since the site area to be disturbed is greater than 1 acre, a Colorado Department of
Public Health and Environment (CDPHE) Stormwater Discharge Permit will be required.
' a. A Stormwater Management Plan (SWMP) is required and will be completed as
part of the (CDPHE) Stormwater Discharge Permit. The SWMP will be updated
as needed and kept on the site for the ready availability to the operator, and so that
' City, CDPHE and EPA personnel can review it during an inspection.
' b. A BMP maintenance folder consisting of an Erosion and Sediment Control
Inspection List (ESCIL) will also be kept on -site to be completed and submitted to
the City of Fort Collins Public Works Department to satisfy the report requirement
stated in the Stormwater Discharge Permit. BMP's need to be inspected at least
7
' once every 2 weeks and after any significant storm event. The ESCIL shall be filled
out after each inspection.
' B. Stormwater Quality BMPs
' 1. The most common associated pollutant from this type of developments is sediment,
which is transported in stormwater runoff to downstream receiving waters. Emphasis will
therefore be placed on improving stormwater quality by limiting and removing sediment
' before it leaves the site.
2. The short and long term erosion control measures previously discussed will reduce, if not
eliminate, the sediment load of stormwater that exits the site.
3. The proposed `StormTech' system will also act as a Sand Filter Basin (SFB), which is
considered to be a structural Best Management Practices (BMP's).
' a. The `StormTech' system will provide a Water Quality Capture Volume
' (WQCV). This will provide extend detention time for more frequently occurring
runoff events, thereby facilitating pollutant removal. The WQCV is approximately
2,374 cubic feet and is achieved at Elevation 5024.83 feet. The WQCV will be
' infiltrated through the gravel base of the storratech chambers and be captured by a
4-inch diameter perforated HPDE underdrain. The underdrain will convey flow to
a proposed manhole located approximately 41-feet northeast ofthe proposed Type-
' 13 Area Inlet. When larger storm events occur, the Type-13 Area Inlet will overtop
beyond the WQCV Elevation and pass via a 15-inch HPDE storm drain into the
proposed manhole. A 24-inch RCP will extend from the manhole and connect to the
' existing storm inlet located in West Elizabeth Street.
b. The pollutant removal range of the `StormTech' system will be similar to an
' extended sand filter basin, which is presented in Table SQ-6 from the Urban Storm
Drainage Criteria Manual, (See Appendix 11). The removal of suspended solids and
metals can be moderate to high, and the removal of nutrients is low to moderate.
VII. Conclusions:
' A. Compliance with Standards
' 1. All drainage design conforms to the criteria and requirements of the City of Fort Collins
Storm Drainage Criteria Addendum.
' 2. Proposed erosion control and stormwater quality measures conform to the
recommendations of Volume III of the Urban Storm Drainage Criteria Manual.
' B. Drainage Concept
8
1. The drainage design for the proposed Campus West Redevelopment site is effective for
the control of stormwater runoff in accordance with the City of Fort Collins's Master
Drainage Plan.
a. Onsite stormwater detention is not required for the site due to the proposed use
being less impervious than the previous uses on the site.
b. The Finished Floor Elevation of the proposed buildings will be a minimum of 18
inches above the Base Flood Elevation. All HVAC equipment will be placed a
minimum of 18 inches above the Base Flood Elevation and will either be ceiling
mounted in commercial instances or roof mounted in residential uses. Air
conditioning condenser units will not be placed at grade.
c. The historic drainage path will be retained.
d. Existing and downstream facilities will not be adversely affected by this
development.
VHL References:
A. City of Fort Collins Storm Drainage Design Criteria and Construction Standards
B. Urban Storm Drainage Criteria Manuals Volume I, M and III
C. Soil Survey of Larimer County Area, Colorado
D. City of Fort Collins Master Drainage Plan
C
' Engineering, Inc.
Project No. GRD - 524 - OS
September 20, 2006
Glen Schlueter
Stormwater Utility
City of Fort Collins
700 Vine Street
Fort Collins, Colorado 80522 - 0580
' Re: Campus West Redevelopment, Fort Collins, Colorado
' Dear Mr. Schlueter,
My opinion of cost for the temporary erosion control measures to be utilized during the project
construction period is:
' 1. Silt Fence 1,145 L.F. @ $2.50/L.F. = $2,862.50
2. Inlet Filter 1 Each @ $250.00/Each = $ 250.00
' 3. Vehicle Tracking Pad Lump Sum = 575.00
TOTAL $3,687.50
With the required 150% contingency factor, the cost is (1.5 x $3,687.50) = $5,531.25
The estimated cost to re -seed the entire site is:
1. Seeding 2.06 Acres @ $775.00/Acre. = $1596.50
Therefore, since the amount of surety is to be the greater of the two estimated costs, the amount
to be secured is $5,531.25.
If you should have any questions or desire additional information, please feel free to contact this
office.
fRe ect ly submitted,
' SS R Engineering, IV.
' Dennis R. Messner, President
1
I
Civil Engineering Consultants
150 E. 29th Street, Suite 270 Loveland, Colorado 80538 (970) 663-2221
EXHIBITS .
VICINITY MAP
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CAMPUS WEST REDEVELOPMENT
1325 WEST ELIZABETH STREET
FORT COLLINS, COLORADO
BEING A PORTION OF THE SOUTHEAST QUARTER OF SECTION 15,
TOWNSHIP 7 NORTH, RANGE 69 WEST OF THE 6TH P.M.,
CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO
LEGEND
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T ELIZABETH STREET/CONSTITUTION AVENUE FLOW PATH APPENDIX E.2
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BL PLATE 7
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F.F.
Elev.=5032.50
F.F. Elev.=5031.50
100 Year Base Flood F.F. Elev.=5030.50
Proposed Ground
Surface
W
b aU,
Elevation Varies
Ei
. o
BFE = 5031w�Q
BFE
= 5030
Existing
Ground Surface
— —�
BFE = 5028
�,
C:6
0 w �
0 co
z
All Uses
at Ground Floor Level
W
to be
Retail/Restaurant
W x
w
J
U
H
1—
Second
Story Use to be Residential
DATE: AUG, 23, 2006
SCALE: AS NOTED
DRAWN: D.A.R.
CHKD: D.R.M
Project No.
CRD-524-05
SHEET
1 of 2
Proposed Ground Surfa
Residential & Building
Utility Room Use at
Ground Floor Level
F.F. Elev.=5033.50
Retail/Restaurant
Use at Ground
Floor Level
�— F.F. Elev.=5032.50
Existing Ground Surface
100 Year Base Flood
Elevation =5031
Second Story Use to be Residential
r-+
N
L
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t
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0
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W
U)
a)
HORIZONTAL: 1"=30'
VERTICAL: 1"=3'
roposed Ground Surface
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m
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0
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z
z x
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w
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f=.
DATE: AUG. 21 2006
SCALE: AS NOTED
DRAWN: D.A.R.
CHKD: D.R.M
Project No.
GRD-524-05
SHEET
2 of 2
ExistinZj Storm Curb — Existing 24" Dia.
Inlet & Monhofe__ -- RCP Storm Drain
5030 5029 � 502$ � ...:--
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r Ir
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1
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LPad-1 Store
df II Existing
Theater Building-
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10
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= 40'
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z
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Ground Surface Contour
w
U
H
♦ _ _ _ Drainage Basin Limit Identifier
T pically Indicates Drainage
law
DATE:
AUG. 23. 2006
Direction
SCALE:
AS NOTED
Concentration Point Identifier
DRAWN:
D.A.R.
4 Basin ' B'1
# Design Point, Basin Number
CHKD:
D.R.M
Area of basin in Acres
5.23 ac.
Project N0.
GRD-524-05
3.4
6.7 0+00C.f.S.
SHEET
QJOC.f.s.
1
of 2
Existing Storm Curb Existing 24" Dia. I
RCP Storm Drain
Inlet & Manhole _ Ln
JE
U
�o� �Q -�
Proposed
f�— Building Prop sed
Buil i�9
Proposed
Building
F'>roposed
Bl Iding
Prop osed A'
Buil ding 2.03 ac.
.2012.0,
0,24(E)
TE)
P1
Existing Storm Inlet
Proposed 24" Storm Drain
Proposed Storm Manhole
—Propoked
Storm M
Inlet
a
Existing
' Car Wash
i
so
sow a3F�J o
'Ir \ N
Proposed 15" Storm Drain r�
V 1
Proposed Underground
- Stormwater Quality System
U
a
z�
w
goo
o
0 20 60
1"=40'
A z
z�CE,-
o
L_ � �
�
� ®
Aaao
-5012-- Typically Indicates Existing
Z,
Ground Surface Contour
Z
soil— Typically Indicates Proposed
z
w
41
Finish Surface Contour
_J
U
1=
Drainage Basin Limit Identifier
— Typically Indicates Drainage
DATE: AIJ2 23. 2006
Flow Direction
SCALE:
AS NOTED
Concentration Point Identifier
DRAWN:
DA.R.
4 Basin B'-�
# �Design Point, Basin Number
CHKD:
D.R.M
Area of basin in Acres
5.23 ac.
Project No.
GRD-524—OS
3.4
Q100c.f.s.
6.7
SHEET
QJoc.f.s.
2
of 2—
AAPE
NDIX I
DRAINAGE
CALCULATIONS
Area -Weighting for Percent Imperviousness Calculation
Project Trde: CAMPUS WEST REDEVELOPMENT
Catchment ID: EXISTING CONDITIONS - SUB -BASIN W
Illustration
-91
5
sula 3
Instructions: For each catchment subarea, enter values for A and I.
Flaw Daa2ion
Cachet m[
Subarea
Area
Imperviousness
Product
ID
(square feet)
(percent)
A
I"
Axl
input
input
input
output
Landscape
7,953
0
0
Drives/Walks
63,021
90
5,671,890
Roof
17,560
90
1,580,400
Sum:l 83,534 1 sum:J 7,252,290
Area -Weighted Percent Imperviousness (sum AVsum A) = 81.92
*See Table RO3 for imperviousness -based values.
' CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
' Project Title: CAMPUS WEST REDEVELOMENT
Catchment ID: EXISTING CONDITIONS - SUB43ASIN'A' (10-yr. STORM EVENT)
I. Catchment Hydrologic Data
' Catchment ID = 'A'
Area = 2.03 Acres
Percent Imperviousness = 81.92 %
NRCS Soil Type = C A. B, C, or D
' II. Rainfall Information I (inch/hr) = C1 ' P1 /(C2 + Td)AC3
' Design Storm Return Period, Tr = 10 years (input return period for design storm)
C1 = 28.50 (input the value of Cl)
C2= 10.00 (input the value of C2)
C3= 0.786 (input the value of C3)
' P1= 1.40 inches (input one-hr precipitation —see Sheet "Design Info")
III. Analysis of Flow Time (Time of Concentration) for a Catchment
' Runoff Coefficient, C = 0.68
Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C5 = 0.65
Overide 5-yr. Runoff Coefficient, C = (enter an overide C5 value if desired, or leave blank to accept calculated C5.)
' Illustration
' ove:iand
tieaeh2 Reaehl
fkW
NRCS Land
Heavy
Tillaga/
Short
F Nearly
Grassed
Paved Areas &
Type
Meadow
Feld
ire/
I
Ias/
IGBmaare
Shall a Swales
LP
nd
W a
rways
S hadt
Corn nce
1 2.5 JE
5
17
10
15
r- 2011
Calculations: Reach Sin
ID I S
Wit
ngth Syr
L Runoff
Coati
it C5
0
1
IV. Peak Runoff Prediction
' Rainfall Intensity at Computed Tc, 1= 5.15 inch/hr
Rainfall Intensity at Regional Tc, I = 3.42 inch/hr
Rainfall Intensity at User -Defined Tc,'I = 4.75 inch/hr
NRCS
Flow
Flow
Convey-
Velocity
Time
ante
V
Tf
fps
minutes
computed To =
Regional Tc =
User -Entered Tc =
Peak Flowrate, Qp = 7.12 cis
Peak Flowrate, Qp = 4.73 cfs
Peak Flowrate, Qp = 6.56 cis
' CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title: CAMPUS WEST REDEVELOMENT
' Catchment ID: EXISTING CONDITIONS - SUB -BASIN W (100-yr. STORM EVENT)
I. Catchment Hydrologic Data
Catchment ID = W
Area = 2.03 Acres
Percent Imperviousness = 81.92 %
NRCS Soil Type = C A, B, C, or D
' II. Rainfall Information I (inch/hr) = C1 ' P1 /(C2 + Td)^C3
' Design Storm Return Period, Tr = 100 years (input return period for design storm)
C1 = 28.50 (input the value of Cl)
C2= 10.00 (input the value of C2)
C3= 0.786 (input the value of C3)
P1= 2.86 inches (input one-hr precipitation see Sheet "Design Info'
III. Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C = 0.76
' Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C5 = 0.65
Overide 5-yr. Runoff Coefficient, C = (enter an overide C5 value if desired, or leave blank to accept calculated C-5.)
' Illustration
- overland t
Reach I;
.' Seach2 0 Rung
Reach 3
1-�
BowdaZY
d
NRCS
—ed]
Short
Grassed
ed
Tyype
t�ddoow IF
Field
Pasturel
Bare
]
Swa �
Shah ales
Lawns
Ground
wat
Sh
SFI
Corn noe
2.5
0
7
10
15
Calculations: Reach I Slope Length 5-yr NRCS Flow Flow
ID S. L Runoff convey- Velocity Time
Coetf ante V Tf
Wit It CS fps minutes
IV. Peak Runoff Prediction
' Rainfall Intensity at Computed Tc, I = 10.53 inch/hr
Rainfall Intensity at Regional Tc, I = 6.99 inch/hr
Rainfall Intensity at User -Defined To, I = 9.70 inch/hr
uompurea I c =
Regional To =
User -Entered To =
Peak Flowrate, Qp = .16.21 cfs
Peak Flowrate, Qp = 10.76 cfs
Peak Flowrate, Qp = 14.94 cfs
S�zej-
Sys
Sulama 3
J,_4
Instructions: For each catchment subarea, enter values for A and].
Flaw Daccriaa
Caromem
Bcwld=ry
Subarea
Area
Imperviousness
Product
ID
(sq.ft)
(percent)
A
1
AM
input
input
input
output
Landscape
10,788
0
0.': .
Drives/Walks
55,884
90
5,029,560
Roof
21,862
90 ' ` '
1,967,580
Sum:j --33,534 1 Sum:1 6,997,140 �
Area -Weighted Percent Imperviousness (sum AUsum A) _ 79.03
'See Table RO3 for imperviousness -based values.
CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title: CAMPUS WEST REDEVELOPMENT
Catchment ID: PROPOSED CONDITIONS - SUB-BASIN'A' (10-yr. STORM)
I. Catchment Hydrologic Data
Catchment ID = 'A'
Area = 2.03 Acres
Percent Imperviousness = 79.03 %
NRCS Soil Type = C A, B, C, or D
II. Rainfall Information
I (inch/hr) = C1 ' P1 /(C2 ; Td)AC3
Design Storm Return Period, Tr =
10 years (input return period for design storm)
C1 =
28.50 (input the value of Cl)
C2=
10.00 (input the value of C2)
C3=
0.786 (input the value of C3)
P1=
1.40 inches (input one-hr precipitation —see Sheet "Design Info")
III. Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =
0.65
Overide Runoff Coefficient, C =
(enter an overide C value if desired, or leave blank to accept calculated C.)
Syr. Runoff Coefficient, CS =
0.62
Overide Syr. Runoff Coefficient, C =
(enter an overide C-5 value if desired, or leave blank to accept calculated C-5.)
Illustration
' wedsod L
EGEM
&each 1 flow
Eewh2 O Bo&mIzig
Fkw Di=tiau
E
CQkhWAZd
Bouidary
NRCS Land
Heavy
Tillage/
Short
Nearly
Grassed
Paved Areas &
Type
Meadow
Field
Pasture/
Bare
Swales/
Shallow Paved Swales
Lawns
Ground
Wate
Sheet Flow
Con ce
2.5 11
5 JL
7 JL10L15
20
Calculations:
ID
Nerland
S
fUft
input
L
it
input
Runoff
coeff
CS
output
Convey-
ante
input
Velocity
V
fps
output
Time
Tf
minutes
output
0.0200
50
' 0.62
N/A . -;
-: 0.17 - `
` 4.92 -
1
0.0100
500
20.00
2.00
4.17
2
3
4
5 .
Regional Tc
User -Entered Tc
IV. Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I = 3.93 inch/hr Peak Flowrate, Op = 5.20 cfs
Rainfall Intensity at Regional Tc, I = 3.39 inch/hr Peak Flowrate, Op = 4.48 cfs
Rainfall Intensity at User -Defined Tc, I = 3.93 inch/hr Peak Flowrate, Qp = 5.20 cfs
11 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD
Project Title: CAMPUS WEST REDEVELOPMENT
Catchment ID: PROPOSED CONDITIONS-SUB-BASIN'A' (100-yr. STORM)
1. Catchment Hydrologic Data
Catchment ID = 'A'
Area = 2.03 Acres
Percent Imperviousness = 79.03 %
NRCS Soil Type = C A, B, C, or D
11. Rainfall Information
I (inch/hr) = C1 * P1 /(C2 + Td)AC3
Design Storm Return Period, Tr=
100 years (input return period for design storm)
Cl =
28.50 (input the value of Cl)
C2=
10.00 (input the value of C2)
C3=
0.786 (input the value of C3)
P1=
2.86 inches (input one-hr precipitation —see Sheet "Design Info')
III. Analysis of Flow Time (Time of Concentration) for a Catchment
Runoff Coefficient, C =
6.74
Overide Runoff Coefficient, C =
(enter an overide C value if desired, or leave blank to accept calculated C.)
5-yr. Runoff Coefficient, C5 =
0.62,
Overide 5-yr. Runoff Coefficient, C =
(enter an overide C5 value if desired, or leave blank to accept calculated C5.)
Illustration
ave:iand
Reaeh 1 g�
J Beglmin&
Flan Dimedw
K
Cahhirlwd
Beur w
NRCS Land
Heavy
Tillage(
Short
Neao
Grassed
Paved Areas &
Type
Meadow
Field
I 11
Pasture/
Bare
Swales/
Shallow Paved Swales
Lawns
Ground
WaterwaysSheet
Flow
Conv nce
2.5 11
5
[
10J
15 11
20
Calculations:
ID I S I L
ff/R It
5-yr
NRCS
Flow
Flow
Runoff
Convey-
Velocity
Time
Coeff
ante
V
Tf
C-5
fps
minutes
output
input
output
output
0.62
"N/A
0.17 ..
4.92
20.00
2:00
4.17
Computed Tc = 9.09
Regional Tc = 1M.
User -Entered To = 9.09
IV. Peak Runoff Prediction
Rainfall Intensity at Computed Tc, I = 8.03 inchi it Peak R wrate, Qp = 11.99 cis
Rainfall Intensity at Regional Tc, I = 6.92 inch/hr Peak Flowrate, Qp = 10.34 cis
Rainfall Intensity at User -Defined Tc, I = 8.03 inchlhr Peak Flowrate, Qp = 11.99 cfs
Design Procedure Form: Sand Filter Basin (SFB)
Designer.
C.W.K.
'
Company.
MESSNER ENGINEERING, INC.
Date:
June 14, 2006
Project
CAMPUS WEST REDEVELOPMENT
'
Location:
1326 W. ELIZABETH STREET, FORT COLLINS, COLORADO
1. Basin Storage Volume
A) Tributary Area's Imperviousness Ratio (t = 1.1100)
I, = 79.03 %
i = 0.79
B) Contributing Watershed Area (Area)
Area = 2.0300 acres
C) Water Quality Capture Volume (WQCV)
WQCV = 0.32 watershed inches
(WQCV=1.0-(0.91 •I3-1.19-12+0.78.1))
D) Design Volume: Vol = (WQCV / 12) • Area
Vol = 0.0545 acre4eet
2. Minimum Fitter Surface Area: A. = (Vol / 3) • 43,560
A, = 792 square feet, Minimum
Actual Fitter Surface Area Used (Should not be less than minimum):
A. = square feet,
Filter Surface Elevation
feet
Average Side Slope of the Fitter Basin (4:1 or flatter, zero for vertical walls)
Z = Using Vertical Walls
3. Estimate of Basin Depth (D), based on fitter area A,
D = feet
4. Outlet Worts
.
A) Sand (ASTM C33) Layer Thickness (18" min.)
inches
B) Non-Waven Gede:dike Fabric Between Sand & Gravel - meeting ASTM
Non -Woven Geotextile Per USDCM Figure SFB-1
D4751 - ADS U.S. Sid. Seive #50 to 00.
Other.
Min. Grab Strength or 100 lbs., min. pertn8ivity of 1.8 / sec.
C) Gravel (AASHTO or CDOT Section 703; 94. #57, or #67)
Tholmess (8" min.)
inches, No.
D) Overflow Elevation At Top of Design Volume
feet
(Filter Surface Elev. + Estimate of Basin De D
4. Basin Inlet
A) Inlet Pipe with Impact Basin; OR
Inlet Pipe with Impact Basin; OR
Inlet Channel with Grouted Sloping Boulder Drop; OR
Inlet Channel with GSB Drop; OR
fEqlnlet
Inlet Channel with Concrete Baffle Chute Drop
Channel with Baffle Chute Drop
B) Ripap Outlet Protection For Pipe or Channel Over Non -Woven
Riprap Outlet Protection
Geote>mle Fabric Wrapped to the Top of the Sand Layer
Other.
5. Draining of Sand Fitter Basin (Check A, or B, or C, answer D)
Infiltration to Subgrade with Permeable
Based on answers to 5A through 5D, check the appropriate method
Membrane: 5(C) checked and 5(D) = no
A) Check box ff subgrade is heavy or expensive day
Underdrain with Impermeable
B) Check box 0 subgrade is silty or clayey sands
rEl
Membrane: 5(A) checked or 5(D) = yes
C) Check box if subgrade is welt -draining soils
Underdram with Non -Woven Geoteldile Fabric:
D) Does tributary catchment contain land uses that may have
5(B) checked and 5(D) = no
petroleum products, greases, or other chemicals
present, such as gas station, yes no
Other.
hardware store, restaurerlt, etc.?
6. Describe Provisions for Maintenance
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APP
.END. [X [I
CHARTS, GRAPHS,
FIGURES AND DETAILS
SECTION 3. HYDROLOGY STANDARDS
3.1 Genera]. Design Storms
All drainage systems have to take into consideration two separate and distinct drainage
' problems. The first is the initial storm which occurs at fairly regular intervals,
usually based on the two to ten-year storm, depending on land use. The second is the
major storm which is usually based on an infrequent storm, such as the 100-year storm.
In some instances the major storm routing will not be the same as the initial storm.
' In this case, a complete set of drainage plans shall be submitted for each storm
system.
3.1.1 Initial Storm Provisions
' As stated before, the initial storm shall be based on the two to ten-year storm.
The objectives of such drainage system planning are to minimize inconvenience,
to protect against recurring minor damage and to reduce ' maintenance costs in order to create an orderly drainage system at a reasonable cost for the urban
resident. The initial storm drainage system may include such facilities as curb
and gutter, storm sewer and open drainageways, and detention facilities.
3.1.2 Major Storm Provisions
The major storm shall be considered the 100-year storm. The objectives of the
major storm planning are to eliminate substantial property damage or loss of
' life. Major drainage systems may include storm sewers, open drainageways, and
detention facilities. The correlation between the initial and major storm
system shall be analyzed to insure a well coordinated drainage system.
' 3.1.3 Storm Frequency
The initial and major storm design frequencies shall not be less than. those
' found in the following table:
Table 3-1
' DESIGN STORM FREQUENCIES
Land UQn Design Storm Return Per;nd
.swim 1•Ja Or St0
' Residential:
(RE,RL,RLP,RP,ML,RM,RMP,
RLM,MM RH) ............. 2-year
100-year
( BP,HB(CZL,IP,IG)....
0-year
-10000-�y�ea
Public Building Areas.........1 -year
Zuu- ear
Parks, Greenbelts, etc.. . ��� Y
Open Channels & Drainageways " " " 2-year 100-year
Detention Facilities __ 100-year
100-year
HSee Table 3-2 for zoning definitions
3.1.4 Rainfall Intensities
The rainfall intensities to be used in the computation of runoff shall be
obtained from the Rainfall Intensity Duration Curves for the City of Fort
' Collins, included in these specifications as Figure 3.1.
3.1.5 Runoff Computations
Storm Runoff computations for both the initial and major storm shall comply with
the criteria set forth in Section 3.2 "Analysis Methodology.- All runoff
calculations made in the design of both initial and major drainage systems shall
be included with the storm drainage plans in the form of a Drainage Report.
Reports submitted for approval should have a typed narrative with computations
and maps in a legible form.
May 1984
' Revised January 1997 Design Criteria
3-1
1
No Text
City of Fort Collins
Rainfall Intensity -Duration -Frequency Table
for using the Rational Method
(31 minutes - 60 minutes)
Figure 3-1 b
Duration
(minutes)
2-year
Intensity
in/hr
10-year.
Intensity
in/hr
100-year
Intensity
in/hr
31.00
1.27
2.16
4.42
32.00
1.24
2.12
4.33
33.00
1.22
2.08
4.24
34.00
1.19
2.04
4.16
35.00
1.17
2.00
4.08
36.00
1.15
1.96
4.01
37.00
1.13
1.93
3.93
38.00
1.11
1.89
3.87
39.00
1.09
1.86
3.80
40.00
1.07
1.83
3.74
41.00
1.05
1.80
3.68
42.00
1.04
1.7-7
3.62
43.00
1.02
1.74
3.56
44.00
1.01
1.72
3.51
45.00
0.99
1.69
3.46
46.00
0.98
1.67
3.41
47.00
0.96
1.64
3.36
48.00
0.95
1.62
3.31
49.00
0.94
1.60
3.27
50.00
0.92
1.58
3.23
51.00
0.91
1.56
3.18
52.00
0.90
1.54
3.14
53.00
0.89
1.52
3.10
54.00
0.88
1.50
3.07
55.00
0.87
1.48
3.03
56.00
0.86
1.47
2.99
57.00
0.85
1.45
2.96
58.00
0.84
1.43
2.92
59.00
0.83
1.42
2.89
60.00
0.82
0
2.8
DRAINAGE CRITERIA MANUAL (V. 1)
RUNOFF
TABLE RO-3
Recommended Percentage Imperviousness Values
Land Use or
Surface Characteristics
Percentage
Imperviousness
Business:
Commercial areas
95
Neighborhood areas
85
Residential:
Single-family
Multi -unit detached
60
Multi -unit attached
75
Half -acre lot or larger
Apartments
80
Industrial:
Light areas
80
Heavv areas
90
Parks, cemeteries
5
Playgrounds
10
Schools
50
Railroad yard areas
.15
Undeveloped Areas:
Historic flow analysis
2
Greenbelts, agricultural
2
Off -site flow analysis
when land use not defined
45
Streets:
Paved
100
Gravel(packed)
40
Drive and walks
90
Roofs
90
Lawns, sandy soil
0
Lawns, clayey soil
0
See Figures RO-3 through RO-5 for percentage imperviousness.
Based in parton the data collected by the District since 1969, an empirical relationship between C and
the percentage imperviousness for various storm return periods was developed. Thus, values for C can
be determined using the following equations (Urbonas, Guo and Tucker 1990).
CA = KA + (1.31i3 —1.44i z + 1.135i — 0.12) for CA >— 0, otherwise CA = 0 (RO-6)
CcD= Kco + (0.858i 3 — 0.786i 2 + 0.774i + 0.04) (RO-7)
CB = (CA + CcD)/2
in which:
i = % imperviousness/100 expressed as a decimal (see Table RO-3)
06/2001 RO-9
Urban Drainage and Flood Control District
DRAINAGE CRITERIA MANUAL (V. 1)
RUNOFF
TABLE RO-5
Runoff Coefficients, C
Percentage
Imperviousness
T e C and D NRCS H drolo is Soil Grou s
2- r
5- r
10- r
25- r
50- r
1 00-r
0%
0.04
0.15
0.25
0.37
0.44
0.50
5%
0.08
0.18
0.28
0.39
0.46
0.52
10%
0.11
0.21
0.30
0.41
0.47
0.53
15%
0.14
0.24
0.32
0.43
0.49
0.54
20%
0.17
0.26
0.34
0.44
0.50
0.55
25%
0.20
0.28
0.36
0.46
0.51
0.56
30%
0.22
0.30
0.38
0.47
0.52
0.57
35%
0.25
0.33
0.40
0.48
0.53
0.57
40%
0.28
0.35
0.42
0.50
0.54
0.58
45%
0.31
0.37
0.44
0.51
0.55
0.59
50%
0.34
0.40
0.46
0.53
0.57
0.60
55%
0.37
0.43
0.48
0.55
0.58
0.62
60%
0.41
0.46
0.51
0.57
0.60
0.63
%
0.45
0.49
0.54
0 .59
0.62
0.65
70
70%
0.49
0.53
0.57
0.62
0.65
0.68
75%
0.54
0.58
0.62
0.66
0.68
0.71
80%
0.60
0.63
0.66
0.70
0.72
0.74
85%
0.66
0.68
0.71
0.75
0.77
0.79
90%
0.73
0.75
0.77
0.80
0.82
0.83
95%
0.80
0.82
0.84
0.87
0.88
0.89
100%
0.89
0.90
0.92
0.94
0.95
0.96
T e B
NRCS H drolo is Soils Grou
0%
0.02
0.08
0.15
0.25
0.30
0.35
5%
0.04
0.10
0.19
0.28
0.33
0.38
10%
0.06
0.14
0.22
0.31
0.36
0.40
15%
0.08
0.17
0.25
0.33
0.38
0.42
20%
0.12
0.20
0.27
0.35
0.40
0.44
25%
0.15
0.22
0.30
0.37
0.41
0.46
30%
0.18
0.25
0.32
0.39
0.43
0.47
35%
0.20
0.27
0.34
0.41
0.44
0.48
40%
0.23
0.30
0.36
0.42
0.46
0.50
45%
0.26
0.32
0.38
0.44
0.48
0.51
50%
6.29
0.35
0.40
0.46
0.49
0.52
55%
0.33
0.38
0.43
0.48
0.51
0.54
60%
0.37
0.41
0.46
0.51
0.54
0.56
65%
0.41
0.45
0.49
0.54
0.57
0.59
70%
0.45
0.49
0.53
0.58
0.60
0.62
75%
0.51
0.54
0.58
0.62
0.64
0.66
80%
0.57
0.59
0.63
0.66
0.68
0.70
85%
0.63
0.66
0.69
0.72
0.73
0.75
90%
0.71
0.73
0.75
0.78
0.80
0.81
95%
0.79
0.81
0.83
0.85
0.87
0.88
100%
0.89
0.90
0.92
0.94
0.95
0.96
06/2001 Urban Drainage and Flood Control District RO-11
' DRAINAGE CRITERIA MANUAL W. 3)
STORMWATER QUALITY MANAGEMENT
TABLESQ-6
BMP Pollutant Removal Ranges for
Stormwater Runoff and Most
'
Co
Ref Be//efa/. (1996J, %iado (>990J,
Probable
Range
for BMPs
Recommended
in Volume 3
Harper& Herr(1992J, Zakatos
Streckeret81(1990J, USGS(1986),, US EPA (1983), 1/eenhuis
& McNemer(1987), Schueter(1987J, Southwest(1995J,
et &1(1989J, lNhipp/e andHunter(>9B1J,
' Type of BMP
Urbonas (1997J
Grass Buffer
(1)
TSS
TP
TN
TZ
TPb
BOD
Bacteria
LRR:
EPR
10-50
10-20
0-30
0-10
0 10
0-10
N/A
N/A
N/A
Grass Swale
0-10
0-10
N/A
N/A
N/A
LRR:
EPR
20-60
20-40
0-40
0-15
0-30
0-40
N/A
N/A
N/A
Modular Block Porous Pavement
0-15
0-20
N/A
N/A
N/A
'
LRR:
80-95
65
75-85
98
Porous Pavement Detention
EPR
70-90
40-55
10-20
40-80
80
60-70
80
N/A
N/A
N/A
'
LRR:
EPR
8-96
70-90
5-92
40-55
-130-85
10-98
60-80
60-80
N/A
Porous Landscape Detention
10-20
40-80
60-70
N/A
N/A
LRR:
EPR
8-96
70-90
5-92
40-55
-100-85
10-98
60-90
60-80
N/A
Extended Detention Basin
20-55
50-80
60-80
N/A
N/A
LRR:
EPR
50-70
55-75
10-20
45-55
10-20
10-20
30-60
75-90
N/A
50-90
Constructed Wetland Basin
30-60
55-80
N/A
N/A
'
LRR:
EPR
40-
50-60 60
4-90
40-80
21
29-82
27-94
18
N/A
Retention Pond
20-50
30-60
40-80
N/A
N/A
'
LRR:
EPR
70-91
80-90
0-79
45-70
0-80
0-71
9-95
0-69
N/A
Sand Filter Extended Detention
20-60
20-60
60-80
N/A
N/A
LRR:
EPR
8-96
80-90
5-92
45-55
-129-84
10-98
60-80
60-80
N/A
'
Constructed Wetland Channel'
35-55
50-80
60-80
60-80
N/A
LRR:
EPR
20-60
30.50
0-40
20-40
0-30
10-30
0-40
N/A
N/A
N/A
(1)LRR Literature reported range, EPR—
20-40
20-40
N/A
N/A
' expected
N/A Insufficient data to make an
probable range
of annual
performance
assessment.
by Volume
3BMPs.
'The EPR rates for a Constructed Wetland
the tributary total impervious area.
Channel assume the wetland
surface area is
'
equal or greater
than 0.5%
of
9-1-99
Urban Drainage and Flood Control District
SQ-17
Project Title: CAMPUS WEST REDEVELOPMENT
Catchment ID: SUB -BASIN 'A' - PROPOSED CONDITIONS
*Output Determined by STORM CAD Hydraulic Modeling Program, Haestad Methods, Inc.
010 (Minor Storm) Peak Runoff Rate = 5.20 c.t.s.
Upstream
Downstream
Length
SecSon
Capacity
Average
Upstream
Downstream
Constructed
Discharge
Upstream
Downstream
Downstream
Node
Node
(ft)
Slze
I
(cfa),
Velocity
Invert
Invert
IUpstream
()
HGL
Energy
0115)
Elevation
Elevation
(R)L
G da
(R)
G(nde
(ft)
(ft
(t
AREA INLET
MANHOLE
41.00
151noh
4.67
4.84
5,024.83
6,024.63
0.005100
620
5.025.93
5,028.26
5.025.55
5.025.99
MANHOLE
EXISTING INLET
26.00124
16.31
4.51
8,021.92
8.021.78
0.005200
6.20
5,022.72
6,023.03
6,022.67
9-022.90
Junction: MANHOLE
Rim: 5,027.50 ft
Sump: 5,021.92 ft
Outlet: EXISTING
Rim: 5,026.28 ft
Sump: 5,021.79 ft
Pipe: 24" RCP
Up Invert: 5,021.92 ft
Dn Invert: 5,021.79 ft
Length: 25.00 ft
Size: 24 inch
INLET
5,027.50
5,027.00
5,026.50
5,026.00
5,025.50
5,025.00
5,024.50
5,024.00
5,023.50
5,023.00
5,022.50
5,022.00
5,021.50
Inlet: AREA INLET
Rim: 5,026.50 ft
Sump: 5,023.00 ft
Elevation ft
Pipe: 15" RCP
Up Invert: 5,024.83 ft
Dn Invert: 5,024.63 ft
Length: 41.00 ft
Size: 15 inch
Q100 (Major Storm) Peak Runoff Rate =11.99 c.ts.
U Node
Notle
Node
Length
eadlon
Capacity
A ,*
Upsbaam
GONnetreanh
Conatrupad
ObM
up=—
(�Epnetrrom
Gwvnhot
Downsrytreyam
(IV
atre
(Call
Vebdb
tmul
Irrvert
8(opa
(rsajPo
(me)
El.r.mIt
Ebva6on
(fm
(t5
Grre
(t0
daEe
(R
fN
(M
fN
AREAINLET
MANHOLE
MANHOLE
41.00
1s"
4;a,
9.61
6,024.a3
6,02A.63
0.006000
11.99
5.027.2a
5,029.76
5,025.84
6.027.
EXISTING INLET
26.00
24 Yhrh
16A1
6.58
6,021.92
8.021.79
0.005=
11.99
6,023.19
5,023.69
5.023.05
5,023..
Outlet: EXISTING INLET
Rim: 5,026.28 ft
Sump: 5,021.79 ft
Junction: MANHOLE
Rim: 5,027.50 ft
Sump: 5,021.92 ft
Inlet: AREA INLET
Rim: 5,026.50 ft
Sump: 5,023.00 ft
5,027.50
5,027.00
5,026.50
5,026.00
5,025.50
5,025.00
5,024.50
5,024.00
5,023.50
5,023.00
5,022.50
5,022.00
"t,021.50
0+00+10+20+30+40+50+60+
Station ft
Pipe: 24" RCP
Up Invert: 5,021.92 ft
Dn Invert: 5,021.79 ft
Length: 25.00 ft
Size: 24 inch
Elevation ft
Pipe: 15" RCP
Up Invert: 5,024.83 ft
Dn Invert: 5,024.63 ft
Length: 41.00 ft
Size: 15 inch
AREA INLET MANHOLE EXISTING INLET
e 2411
rY r1 !%
"BMP" EFFECTIVENESS
CALCULATIONS & SCHEDULE
' RAINFALL PERFORMANCE STANDARD EVALUATION
PROJECT: CAMPws W EsT fzc or. E D m STANDARD FORM A
COMPLETED BY: 55n/E4 FVe,4. ll7E"v"s Islesivaj)DATE: 00-Z2-66
DEVELOPED
ERODIBILITY
Asb
Lsb
Ssb
Lb
Sb
PS
SUBBAgIN
ZONE
(ac)
(ft)
C0
(feet)
M
M
ENT)RE
To
M006 aJlTE
Af, , 2 S
J'
MARCH 1991 8-14 DESIGN CRITERIA
EFFECTIVENESS CALCULATIONS
PROJECT: STANDARD FORM B
COMPLETED BY: M ssiv- FA1 1/6',1,N/S MswEK2-,, DATE: 9`-Zy•6Co.
Erosion Control C-Factor P-Factor
Method Value Value Cominent
S,G.T AFVeE /.00 6,50
/NLar /=/tT�'e I'av O SO
UEN j C L a 7lz4eJG.V O 1040 09.0s
/'AVe kn 7— 0,.n 1 /•o c�
QA/IE JDrL, / , �Q /• 00
MAJOR
PS
SUB
AREA
BASIN
BASIN
(Ac)
CALCULATIONS
FNTIRE
78.25
2.O(o
Z.6&
640eg $d,L - /,5.4� 1AC-.
S ,7t
\rl-Isc.� ' G' e C�►,c+ta x (•�G� T Co,ot �_ ta, SQ�� = 2.010
W4eA 'CI
px /o0
�i - �a. 7 x ®, zE /o v
Ile h/C/t Truck'nq i�ad
•
�AS 40 �C�nSl�/Brca! aS
MARCH 1991 8-15 DESIGN CRITERIA
CONSTRUCTION SEQUENCE
'PROJECT: C,AmPAei STANDARD FORM C
SEQUENCE FOR -19 ONLY COMPLETED BY: &4.55,vc-e 6Aeyc DATE: �?-
Indicate by use of a bar line or symbols when erosion control measures will be installed.
Major modifications to an approved schedule may require submitting a new schedule for
approval by the City Engineer.
' YEAR
MONTH QClI NOV DSc�JfW nt�I Abe .� �tHY�Jav€II�NGYI�4�r I.TI
' OVERLOT GRADING
WIND EROSION CONTROL
' Soil Roughening
Perimeter Barrier
Additional Barriers
' Vegetative Methods
Soil Sealant
Other
' RAINFALL EROSION CONTROL
STRUCTURAL:
Sediment Trap/Basin.
Inlet Filters
Straw Barriers
' Silt Fence Barriers
Sand Bags
Bare Soil Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving -
other.. FeundaA,oh ${rualu
VEGETATIVE:
' Permanent Seed Planting -
Mulching/Sealant
Temporary Seed Planting
' Sod Installation
Nettings/Mats/Blankets
other
STRUCTURES: INSTALLED BY MAINTAINED BY
VEGETATION/MULCHING CONTRACTOR
1 DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON
' MARCH 1991 8-16 DESIGN CRITERIA
AVPE
ND [X [I
CHARTS, GRAPHS,
FIGURES AND DETAILS
SECTION 3. HYDROLOGY STANDARDS
3.1 General Design Storms
All drainage systems have to take into consideration two separate and distinct drainage
' problems. The first is the initial storm which occurs at fairly regular intervals,
usually based on the two to ten-year storm, depending on land use. The second is the
major storm which is usually based on an infrequent storm, such as the 100-year storm.
In some instances the major storm routing will not be the same as the initial storm.
' In this case, a complete set of drainage plans shall be submitted for each storm
system.
3.1.1 Initial Storm Provisions
' As stated before, the initial storm shall be based on the two to ten-year storm.
The objectives of such drainage system planning are to minimize inconvenience,
to protect against recurring minor damage and to reduce maintenance costs in
' order to create an orderly drainage system at a reasonable cost for the urban
resident. The initial storm drainage system may include such facilities as curb
and gutter, storm sewer and open drainageways, and detention facilities.
3.1.2 Major Storm Provisions
The major storm shall be considered the 100-year storm. The objectives of the
major storm planning are to eliminate substantial property damage or loss of
' life. Major drainage systems may include storm sewers, open drainageways, and
detention facilities. The correlation between the initial and major storm
system shall be analyzed to insure a well coordinated drainage system.
' 3.1.3 Storm Frequency
The initial and major storm design frequencies shall not be less than those
found in the following table:
Table 3-1
DESIGN STORM FREQUENCIES
Land Use or ZoDesign Storm Return Period
ningf init,at c�
' Residential:
(RE,RL,RLP,RP,ML,RM,RMP,
RLM,MM RH).. 2-year
Busis: " " " '100-year
' ( 19 ,a ' C IL,ZP,IG)................. 0-year 100� -y e
Public Building Areas ............... 10-year ear
Parks, Greenbelts, etc.--- ..................... 2-year 100-year
Open Channels & Drainageways Y
' Detention Facilities -_ 100-year
100-year
HSee Table 3-2 for zoning definitions
' 3.1.4 Rainfall Intensities
The rainfall intensities to be used in the computation of runoff shall be
obtained from the Rainfall Intensity Duration Curves for the City of Fort
Collins, included in these specifications as Figure 3.1.
3.1.5 Runoff Computations
Storm Runoff computations for both the initial and major storm shall comply with
the criteria set forth in Section 3.2 "Analysis Methodology.,, All runoff
calculations made in the design of both initial and major drainage systems shall
be included with the storm drainage plans in the form of a Drainage Report.
Reports submitted for approval should have a typed narrative with computations
and maps in a legible form.
May 1984
' Revised January 1997 Design Criteria
3-1
No Text
' City of Fort Collins
Rainfall Intensity -Duration -Frequency Table
for using the Rational Method
' (31 minutes - 60 minutes)
Figure 3-1b
Duration
(minutes)
2-year
Intensity
in/hr
10-year
Intensity
in/hr
100-year
Intensity
in/hr
31.00
1.27
2.16
4.42
32.00
1.24
2.12
4.33
33.00
1.22
2.08
4.24
34.00
1.19
2.04
4.16
35.00
1.17
2.00
4.08
36.00
1.15
1.96
4.01
37.00
1.13
1.93
3.93
38.00
1.11
1.89
3.87
39.00
1.09
1.86
3.80
40.00
1.07
1.83
3.74
41.00
1.05
1.80
3.68
42.00
1.04
1.77
3.62
43.00
1.02
1.74
3.56
44.00
1.01
1.72
3.51
45.00.
0.99
1.69
3.46
46.00
0.98
1.67
3.41
47.00
0.96
1.64
3.36
48.00
0.95
1.62
3.31
49.00
0.94
1.60
3.27
50.00
0.92
1.58
3.23
51.00
0.91
1.56
3.18
52.00
0.90
1.54
3.14
53.00
0.89
1.52
3.10
54.00
0.88
1.50
3.07
55.00
0.87
1.48
3.03
56.00
0.86
1.47
2.99
57.00
0.85
1.45
2.96
58.00
0.84
1.43
2.92
59.00
0.83
1.42
2.89
60.00 1
0.82
0
2.8
DRAINAGE CRITERIA MANUAL (V. 1)
RUNOFF
TABLE RO-3
Recommended Percentage Imperviousness Values
Land Use or
Surface Characteristics
Percentage
Imperviousness
Business:
Commercial areas
95
Neighborhood areas
85
Residential:
Single-family
Multi -unit detached
60
Multi -unit attached
75
Half -acre lot or larger
Apartments
80
Industrial:
Light areas
80
Heavy areas
90
Parks, cemeteries
5
Playgrounds
10
Schools
50
Railroad yard areas
15
Undeveloped Areas:
Historic flow analysis
2
Greenbelts, agricultural
2
Off -site flow analysis
when land use not defined
45
Streets:
Paved
100
Gravel(packed)
40
Drive and walks
90
Roofs
90
Lawns, sandy soil
0
Lawns, clayey soil
0
* See Figures RO-3 through RO-5 for percentage imperviousness.
Based in parton the data collected by the District since 1969, an empirical relationship between C and
the percentage imperviousness for various storm return periods was developed. Thus, values for C can
be determined using the following equations (Urbonas, Guo and Tucker 1990).
CA = KA 4.3 —1.44i' + 1.135i — 0.12) for CA >— 0, otherwise CA = 0 (RO-6)
CcD = Kco + (0.858i' — 0.786i2 + 0.774i + 0.04)
CB = (CA + CCD)12
in which:
i = % imperviousness/100 expressed as a decimal (see Table RO-3)
(RO-7)
06/2001 RO-9
Urban Drainage and Flood Control District
DRAINAGE CRITERIA MANUAL (V. 1)
RUNOFF
TABLE RO-5
Runoff Coefficients, C
Percentage
Imperviousness
Type C and D NRCS Hydrologic Soil Groups
2- r
r
25- r
50- r
100 r
0%
0.04
0.25
0.37
0.44
0.50
5%
0.08
0.28
0.390.46
0.52
10%
0.11
d5-vr10-
0.30
0.41
0.47
0.53
15%
0.14
0.32
0.43
0.49
0.54
20%
0.17
0.34
0.44
0.50
0.55
25%
0.20
0.36
0.46
0.51
0.56
30%
0.22
0.38
0.47
0.52
0.57
35%
0.25
0.33
0.40
0.48
0.53
0.57
40%
0.28
0.35
0.42
0.50
0.54
0.58
45%
0.31
0.37
0.44
0.51
0.55
0.59
50%
0.34
0.40
0.46
0.53
0.57
0.60
55%
0.37
0.43
0.48
0.55
0.58
0.62
60%
0.41
0.46
0.51
0.57
0.60
0.63
65%
0.45
0.49
0.54
0.59
0.62
0.65
70%
0.49
0.53
0.57
0.62
0.65
0.68
75%
0.54
0.58
0.62
0.66
0.68
0.71
80%
0.60
0.63
0.66
0.70
0.72
0.74
85%
0.66
0.68
0.71
0.75
0.77
0.79
90%
0.73
0.75
0.77
0.80
0.82
0.83
95%
0.80
0.82
0.84
1 0.87
0.88
0.89
100%
0.89
0.90
0.92
1 0.94
1 0.95
0.96
Tvpe B NRCS H drolo is Soils Group
0%
0.02
0.08
0.15
0.25
0.30
0.35
5%
0.04
0.10
0.19
0.28
0.33
0.38
10%
0.06
0.14
0.22
0.31
0.36
0.40
15%
0.08
0.17
0.25
0.33
0.38
0.42
20%
0.12
0.20
0.27
0.35
0.40
0.44
25%
0.15
0.22
0.30
0.37
0.41
0.46
30%
0.18
0.25
0.32
0.39
0.43
0.47
35%
0.20
0.27
0.34
0.41
0.44
0.48
40%
0.23
0.30
0.36
0.42
0.46
0.50
45%
0.26
0.32
0.38
0.44
0.48
0.51
50%
0.29
0.35
0.40
0.46
0.49
0.52
55%
0.33
0.38
0.43
0.48
0.51
0.54
60%
0.37
0.41
0.46
0.51
0.54
0.56
65%
0.41
0.45
0.49
0.54
0.57
0.59
70%
0.45
0.49
0.53
0.58
0.60
0.62
75%
0.51
0.54
0.58
0.62
0.64
0.66
80%
0.57
0.59
0.63 1
0.66
0.68
0.70
85%
0.63
0.66
0.69
0.72
0.73
0.75
90%
0.71
0.73
0.75
0.78
0.80
0.81
95%
0.79
0.81
0.83
0.85
0.87
0.88
100%
0.89
0.90
0.92
0.94
0.95
0.96
06/2001
Urban Drainage and Flood Control District
RO-11
DRAINAGE CRITERIA MANUAL (V. 3) STORMWATER QUALITY MANAGEMENT
TABLESQ-6
' BMP Pollutant Removal Ranges for Stormwater Runoff and Most Probable Range for BMPs Recommended in
Volume 3
Ref Be//et at. (1996), Co%rado (1990J, Harper&
Hen(1992), Lakatos & McNemer(1987), Schue%r(1987J, Southwest(1995),
Streckeret a1. (1990), USES (1986), USEPA (1983), 140enhuis eta/. (1989) Whipple andHW#W(1981J, Urbonas (1997)
' Type of BMP (1)
TSS
TR
TN
TZ
TPb
BOD Bacteria
Grass Buffer LRR:
10-50
0-30
0-10
0-10
N/A
N/A
N/A
EPR
10-20
0-10
0-10
0-10
N/A
N/A
N/A
'
Grass Swale LRR:
20-60
0-40
0-30
0-40
N/A
N/A
N/A
EPR
20-40
0-15
0-15
0-20
N/A
N/A
N/A
' Modular Block Porous Pavement LRR:
80-95
65
75-85
98
80
80
N/A
EPR
70-90
40-55
10-20
40-80
60-70
N/A
N/A
Porous Pavement Detention LRR:
8-96
5-92
-130-85
10-98
60-80
60-80
N/A
'
EPR
70-90
40-55
10-20
40-80
60-70
N/A
N/A
Porous Landscape Detention LRR:
8-96
5-92
-100-85
10-98
60-90
60-80
N/A
EPR
70-90
40-55
20-55
50-80
60-80
N/A
N/A
'
Extended Detention Basin LRR:
50-70
10-20
10-20
30-60
75-90
N/A
50-90
EPR
55-75
45-55
10-20
30-60
55-80
N/A
N/A
' Constructed Wetland Basin LRR:
40-94
-4-90
21
-29-82
27-94
18.
N/A
EPR
50-60
40-80
20-50
30-60
40-80
N/A
N/A
Retention Pond LRR:
70-91
0-79
0-80
0-71
9-95
0-69
N/A
' EPR
80-90
45-70
20-60
20-60
60-80
N/A
N/A
Sand Filter Extended Detention LRR:
8-96
5-92
-129-84
10-98
60-80
60-80
N/A
EPR
80-90
45-55
35-55
50-80
60-80
60-80
N/A
' Constructed Wetland Channel' LRR:
20-60
0-40
0-30
0-40
N/A
N/A
N/A
EPR
30-50
20-40
10-30
20-40
20-40
N/A
N/A
t11LRR Literature reported range, EPR— expected probable range of annual performance by Volume 3BMPs.
N/A Insufficient data to make an assessment.
'The EPR rates for a Constructed Wetland Channel assume
the
wetland surface area
is equal or greater
than 0.5% of
' the tributary total impervious area.
9-1-99 SQ-17
Urban Drainage and Flood Control District
NOTE:
1. THE LOWEST FLOOR (INCLUDING aLSEYENr
OR CRAaLW M WAC WILL eE REQUIREDS
TO BE EIJI AT LEAST 1$' ABOVE THE
BASE ROOD 0.1DATKKr.
z A ROODRwN usE PERMIT WILL aE REQUIRED - ' � HEC-RAS Cron Section from tt
roR EAOI s1rAlcnBE AND Au snE COIeTNICIDII i
ELOADMi w THE ELOaO ILAAN City of Fort Collins Floodplain Mop e
F
]. AN T K cxD FEW EAND MN CERrIEFGOW S 6
Must BE COMPWF A AND APPROV TR PRIOR
IO THE RELEASE a A CO FOR ANY STRUCTURE \ / _ - �� �/ ' ^'^' �^•T !i e
W 111E RaODPVrYL 8
1. THE M-000PL1Yl RIFORNATKIN sIgWN Oft THIS 0 -
PLAN COMES rINNr THE L RECENT CITY O ` \ A S — —• -- w . en (` er
G
OF mRr GOWN$ FORT
COIAIN IW CHECK„ 0 � � -
DWTINE3 THE Cm OF FORT C UT U SrOXYYVND e, R
OEPARr11ET FOR CURRAM uPGTES AND BON Flood C�Wation from
REVlsnra ro THE rLaooxAw wP. City of Fart Collins FModplain Map i. --- - R••rr
E%Iellnq Storm Intel
0 i -
0j I k
MI �a -- - �� - " e Existing 150 Dia.
Existing 15• Dia. 1 /Ut RCP Storm Drain SECTION A —A 8
RCP Storm Drain Existingbt Vertical
sting - Curb k Clrltsr (Typ.) / Existing 111!
Curb Inlet n Existing Storm Curb Curbed Median
k Manhole N Inlet k Manhole - --- -- _- _
T— I T— t E T I Exsting Storm Inlet
Existing �! __ _ ` ' Existing24' Dia.
2a• Dia. ROW ��q Y Existin a r RCP Sorm Drain
RCP I / Vanes 4000, Existing 7'd: Wide ' 12' Wide s\0\1�' i _ _ - - SDI rrr.. sr,r el.ty...l o
Storm Existing / Concrete Gut4r / ��l i
Drain 6' Wids / k Blow tam Sidwalk -- - - 24 LSD'-
Crosspan-_
a
mow'
posed 244 Dia.
RCP Storm Drain
• - $
\ e _ _.. Proposed Storm
\ / _.1\�\.�.t` /. a Sewer Manhole
y( City h Risk, i I Proposed 4• Dia.
Floodway ndary Ae I HOPE Underdraln
\ \ \ 4 \ ISF
A fV5 SECTION B—B Fr+al
Proposi 15•.Dia�
NOTE: Sic evolk Chia I e RCP Storm Drain
Y\ P d Buildina IIIFy
` . Y SF Nob Sib constriction Ima b M pl«eJ arounW .I,LMe
m \ n Roof Do spouts D horgs Corovuctl« wkkN xcue b a eom Pow ALwn�a of silo
wo 32.50 FIOW on Adjacent ..WM Cos' V 1 C
\ _ Proposed uildinq
Finish rldl Flpor SEE DE T L SHEET [Elei
2.03 a I Proposed
54 S\0 0 c
_ .2 12. Type-13 LJ1 O f - oposed uildinq 10' Utility Storm Inlet r
Finished Floor Easement S _- 1� 1 ^ A 1 EDOW • a
A �� S 'I .50 Proposed Curb L.
� C. Y �..Y 5 W
T ,el Y ICy-1 0
C5 Sock Inlet Filter T�yy
_ I / I SEE DETAIL SHEET 12--�12--' Grduncj Sudau Contourn9
I / I / —t an, Ie 1/ I Car Ty y
I t roposed Buildin 1 .. / a•'IE3---. I /I 1 —�12— Finlah llSUAaca Callou�aed
Finished fbo I l / 26'Uli I
�\ L d EML•.=SOJ2.50 1 . / - - - lE)- A h Emer�my I I 1 _ `,w �i Drainage Basin Limit Identifier a
1 Typical inQdlIcatn' Ldc on yy E.
60 1.ROW of Do nipdut.k walk Chase _-�— � ' I ~OOO- of Ditch or Indicates flawlins a aZ
\ . 7' Utility I ++ \ ' t als
N Q p�1i
Easement / I r� _ _ I � O+I-w- Typically IndicotH Silt Fence y� I
Vlhl f Proposed Underground
I Stormwatar Duality System 9Q�pgYp Typically Indicates Vehicle w $ s
g 2' Access Ilk
26',UUlity 1 I - } �T _ _ got Tracking Control Pod [r I�qj pj
\ e Utility Eassor act sesTtEy - 1�\ `Y2
I
t
Access/�
�/ •I�IyI`lI1I II I T w illy
Indicates Curb
Proposed asemt SInlet nK*rIndicates Drainage a40
gee'wla— ToDkaDlvection
Msealk -�ConcenVafion Point kentifier
Cidached _ 6V IV
o zo 60
i120' /4 Basin 'B-PoBasin Number
flArea of basin in AcrAd
yF
EIw.05033.50
0 0
523 ac. as
e ert
RAN APPROVAL
\ O Existing---�toExia6nq Limit I It �I ry CeNM, ColereM
O O e e 100-yr. \ of Shallow Floods I APPROV
/ _
g \ � (Less Than 1-( I Proposed Silt Fence Aw- � DALE: sm is amr.
O�O U O Boundary — — — II Application Along
\� ` y Weal. North, East, k CHECKED BY: scau� N°TE°
®G \ 1 Troe ad ` 1 I SEE DETAIL SHEET 11 CHECKED BY: 'ry.A..�t(sI South Boundaries.s�o�
rse.�1k�E�p se' R` C.W.K.
Y \ \ y I CALL UTILITY NOTIFICATION 'EGH•- CMLD: DeM
(F los r I / CENTER OF COLORADO
0, kloahed •V(� 5' Utility — y ` d 4 _� i' 1� / / FOR THE M.IRKINO Or U CHECKED BY: if/L ge}eL No.
a o _ _ _ _ _ 1-800-922-1987 OR— �_ GRD-524-05
fxie6nq 5' \ _ _ _ _ i34-6700 IN METNO DENVER CHECKED BY:
/ \ \ - / i CALL 2-BUSINESS Day IN IDVANCE i -Sete.' SHEET
p sa.'' e� BEFORE YOU DIG. GRADE, OR IXGVATE •I '2
Sidnalk ^WFj. \ Easement - - MEMBER UnUTIESERGR0uN0 CHECKED BY: -� 5 of J
\ —
i
I
v r:
err A:
D
eOR
ra '
4�
nu
FLpp4LL G
A
e•�rV
Yco o-p
Na_ 13 GRAZE MAL
nW ar, ly 13
(� re
1jJ�
j . 'j w f GNP& rarw
1 li---II I I 1 I�
�� erarsrrra�srr
:w�wra� a
_ `r rr..rrrru.
1111�� Jll w'r`uw__r_rswerk
r r♦ ww
Aurruewrrea
earrrsr usrlrr
�rsrrawacrssw
urr�eufa
arrc.aaec err rer�Y�r
l errrrsrrerwerreru
GRATED TYPE-13 INLET WITH DROP BOTTOM
NOT TO SCALE
STORM SEWER CUSS B
EB DDING-REQUIRMENTS
HOT TO SCALE
Y Ya N ��ry
�VIpfLNYIY FIB
. ., r era � Ir+rea wrx Ierr
oY �rM [-1neW{61d
.rrl `�ral:a
•"'Lr'8C FZV"910=d6eY
�r r Y rs
Lira lox err r _era
YY.
YYrurat YY
OR
rm..
Ra arc
FLATim
TO? STORM SEWER MANHOLE DETAIL
NOT TO SCALE
Proposed B' C6.
Sanitary Sower Swe-
Proposed Sanitary
Sewer Manhole
Proposed a -
IN Sower So
72 Proposed 6' Fireharnlowers
(6SC-310 SC-b
(6 Rows of 12)
— — — SEE DETAR S-SHEIX 434 — — — _ —Pmo
Proposed Building
h
Proposed 2"
Water Service Proposed B' SanitaCry
Proposed 6' Dia. Water Line \ .9s'�s�eA.pw�r..9�sfl.,e
Install CManout for Proposed 24' Did.
4' Underdrain HOPE Header Pipe
posed (6) 12' Proposed Fire
Manifold Pipes I Hydrant Aesembly�
�- — -'- -- "o-'-
(� m
-1- y —il j_-Proposed ----Q- -- -p-- ... _-
m I Vertical Curb Existing _ _• — — _
Vertical Curb T� Existing
II ) Existin 1 dc Culler Electrical Vault
Fenu 9 ' Existing I
Car Wash I
1 I Proposer Type-13
This design and drawing toed Existing Natural �owSt , O+OO.G0
tensed to campy with monWalwere Gas Service Line Gr te=5026.50
recommendotiooe prior to 9
installation of Stormtech' to Car Wash Inv.15 Na,5024.83
Inv.24' Sa,5023.00
1
12'
Water I (R iw toElse. Cl omnce
me for Str
1' of Pr
,S' Did. RCP
VII 1 I Concrete
oda t 7' ttter I
sL�4� 11 k Bike Lotus I
.s— — -1 T a— — -
Existing B' Die.
ar�sed I I I Sanitary Sewer M
28' Wide I Stub Out Una 31,
Og
Driveway I Existing 24' Din.
Enlr Inca RCP Storm Drain
e�.f�
Water Une
II Existing Natural
Gaa uain
rE I iting Street Light
to be Relocated
Exierinq Storm IN
St.0+B6.00
l Grote- 5026.28
Y f III
Inv. 15'NM 5022.07t
Inv. 24'Ws 5021.794
I l Inv.24'Ea 5p21.72t
A M I Inv.24'SWI,5021.79
—
posed-
---
T2444'15a. RCPExisUrag
torm Drain
Water Service
Existing
to Car Wash
Landscape
Planter
Proposed 4''
HOPE
Perforated
Underdroin
nv L ��--- i
Y II I„a1 �etinq 15 Die.
1 `Ex-'ROP Slorrn Drain I
I I Existing Vertical Curb)
u1u
5 20
0 10 30
1"= 10'
7 U
CALL UTILITY NOTIFICATION
5026 CENTER OF COLORADO a 4I e
1-800-922-1987 ca s c
534-6700 of werso orivEa
fN1 2-BUSINESS DAK IN ^WE E-I Gi 6i
BEFORE You M. MADE, M DIGVATE
5025 FOR THE MARKING OF UNDERGROUND h1 N< a
MEYBFR UTILITIES U 1 3
1 rwns 0
NOTES: (k t
24 1. oimensaws shown for News anon ore O q
.Weed from center to .enter of
1 -yr, mists am i d a try C
2. Dennisa INa xi of uMrpaune uliki y O W a
4 approximate, Contractor whon nextr U 0
5023 Wendy depth• Now. ON bcalgn of all
underground UtIPMes poor to storm
dram installation. N any existing YWily�1-1
r
Conflicts with the proposed design as
W shown on these plane and warrants
revision to me cei the conuacttr
H..L fff yg sh ll wse weer arm hoary Me eryw ior�
Immediately. H J
x
5021 w
25.00' of Proposed City of Fog Collins. Colorado u of
24' Did. RCP 0-11.50% APMov'LL
y MATE SEE. 18. 200f
SO20 �� SU : AS N01EI
rpO ___ G ownC CHECKED_ DRAWN: C.W.K.
G £ ^�
CHECKED n: col D: D.R.M.
Project NO.
N l w s - ern a e 2 GRD-524-05
FN f Wn
e �,+,rr c o^ nN� clfECKm Bv: _tw_ SHEET
Ems" �' , CHECKED NO: 8 of 13
LE G E IV ED
Surffx* ContExisting
- Existing Storm Inlet
^ -- - - -_ - Grate=5026.28 -301¢ Typ¢ally Indicates Propowd
1171 EAVU Inv.15'N=5022.07 Fmiah surfau Contour
_ warm Inv.24"W=5021.78 =olly lnSu fac Existin°
Existing Curb Inv.24'E=5022j, 7tT ]BAB PP kn
Exiatin9 GUro Inlet & Manhole Existing 15 Dla. Inv.24'SW=502JJg 1 V x owmaM Surface ENvat
Inlet & 1lpnhole '"- RLn.S070.&1 Existing mark RCP Storm Gran - � �i �fi or Flew Lim of Culler
I q Inv.151Fa/023.07 Curb & Gutter (Typ) Existing I V* - Typically IMkalae Proposed
I Inv.24'W=5024.12 - �rbed Median l / / } r Flow
Ss of Elevation m
Inv.24'E=5023.67 -- - - - - T- R FTC- � / Existing 24' Did. or Fktw Lines of Gutter
i -�V_ E S T -�L-I 3 _A--B-E r _ i .�il�•� U CRCP Storm Drain -�- T pkally Indicot•e Existing
Existing 15' Do �_ �._ - 2e(01/Existing / / 3 _ - �.LYuro &Gutter
RCP Sl rm Dram '": P sed ROW _,eal� Existing 7 3 Wide ,q5 12' Sri 40
Existing 24" q / R•taWn�q wall Varies io'" Concrete Gutter i Attached
25' Rod.
g Existing / & Bike Lane/ Proposed i _{••
Dia. RCP / / sidwalk �- _ 0 20 60
Storm Drain 6' Wide / Proposed steps Proposed Steps / Stop .. a-_ _ 2a" 2e.Nj p2a.7� o.•� _ ' _ 1 - 20
_4t,
Crosspan _ _... _-_ _� - _ _ -�1i 50-- - - - �71.aa �-
2aso-- Proposed 24" Dia.
�4"5 ~'] roposed ifj} f Q e 2= _ M RCP Storm Drain
` 3a.32 \ 2aJ3 BASE 2e.N GY 7461 L.]5 steps Y]b t7le 27.1 27. I
25' Sewer •Ma Manhole n
f� zz .r sa •, 4n 70.18 TOP 27�e Rad. Rim=5S=502 PFINISHAVEMENT
BOVE SotwK TO EOrE'. /e• la ,/7' Rlt R. n
30.21 x TOP y/�p _ Inv.15"5=5024.62 PSURFACE
3 ex .,« II' Proposed ( �Inv.45=50220092 SURFACE 1 n
\ Tap b'n Proposed. TOP I 15' Dia. RCP \ o
= I I I Retainin9I a „ Stonn Drain
\ 3i.12 d I Wall � Pro osed T Pe 13 1k' •e ~
Proposed Building dBuilding 2Zt; p y Is 2_ �a IIE81R cDxlxawlls
\ Rnished Floor \I I 5.5 Ro . Area Storm Inks
\ \ flev.=5032.50 Proposed ulldin9 Flnish Floor Grate=5026.50
Fini poor Elw.=xd30.50 I Inv.15'N=5024.83\
Inv.24"S=5023.00 \ ONSITE THICKENED EDGE SIDEWALK DETAIL 8
Proposed 8' Wide>b']4. 1 TI 5.5' Thickened sex'
yyyypicaly In icates anon Ede Sidewalk I NOT i0 $r.,r I f yj
IIF Altachid walk I I I\ I \ \ ar Down 1 & Sid alk Chas g 2N2a I Existing Vertical Curb) W
$E DETAIL SKEET A I SEE DETAIL
THIS SHEEP
Y 2LW Existing C e o
�r Car Wash
T:
I \ C.
II \ 1.e.I
ys' R I ' w
1 ?2M us , Propossd Il 2{ '^
\ 3,,22 Proposed Step 2 W, k / d°' 12 1 I I Curb Cut V 1
SEE v s = N
x 1 rqe y / _ _ B' Thlclun•d 1(q_ Lsn I TH 5 DETAIL
s .
\ 7' Utility T..C. / Edpt Sidealk sp�.,�, I. I _ .
\ / iFE DETAIL -'t4 Y Ra0. za• 6' C s' 2{ C ti
Easement 5' Ras. / THIS sH I I _
60' Row\ Proposed &AdM / �' I Proposed Vertical TYPICAL ONSITE CURB CUT DETAIL ui
I \ .,." Finished Floor I I I . mean Curb & Gutter N.T.S. C g
Acc�ss Elw.=5032.50 Fd gB.ln - - I I 1 SEE DETAIL THIS SHEET W
& UGlirylI� semis TOP OF CUIIB
smile- N s � B I 5• F -24'� aO4uN[
I B.C. 5' Rod. I / \ - Rod. °�(E) 2•_e• C i
31.eelx I I \ \ - - -
a
"r ym Indicates Proposedr i- - - J \ \ - I�II4 I
\ I 5132 ' ems/ I Vertical OuMaN P- i ! I / +Ih a
`.._, 2.5Rad.15'/Rod.l I taro lt« &cu/ /r _ SECTION C-C
SEE DETAIL THIS SHEET 1 s' Rod.
Proposed sup
Proposed Building
Floor _2.os 5' Rod.' I� \\ _ - I I I ze sT dam I "L : x E
\Elov.=5033.50 I _ - I 16.74' 'li I
e U se scA rpmy
\Sz.4e I y x. \ - - - - &Drain • \ ` V
FILT W Eowm // I ONSITE VERTICAL 6' INFALL
\ 1 lTaO I n 5' Utility Casement +'-e' e, CURB &�GUpTT�EER DETAIL ��
32.io isxs aoa. 2 ' Rod„ 25' Rod., �I I 1/;
I VIR
y
Ee3 qe Sidewalk e 20' Utility k - - - - - �5 I
N SEE AIL 5' R Y ` I NOTE: GU7
\ Emergency \ p Proposed Vertical p
d THIS 51(EET ¢ 4 Infoll Curb & Gutter 5.51 / I FOR P,ww1w u5T PAti�K711 1ltlfpiESS.
G ergeri 4.5' Rad. Rp I 'I '�'
Easement SEE D� -� I I RUUt m THE FINAL GEOTECHMKAL
3J.11 x / I I N . PRO IIC NO. 2 6Y TOURgr17. Wll, fsT
INC. PROJECT N0. 2005501]. z
\�s Rad. ad. T 2L50 I ONSITE VERTICAL 6" OUTFALL
�+r CURB & GUTTER DETAIL Z"
I \ n Los - .0 NOT TO SWE u
\ 33.Tdx w
N.39 2d.e2 29. 3 .09 29]2 j I / City Of Fort Collins. Colorado
�[ x
- - __ -b- UTILITY MAN AMRO7` -582E)-J3.4Proposg APPRO "
-�d>E sPv. le . aooe
Existin 5' IHilitY Curb Cut Fencelna � 1
40
5' WidEasement SEE DETAIL CHECKED BY: 6C.E etNeTm
Ar�THIS SHEETC.W.K.>idawak MA(E) - �___
_ _I CHECKED BY:
I Existin I CALL UTILITY NOTIFICATION - C1eok a➢w
Garage it I I \ \ - - _ _ _ CHECKED -
CENTER OF -198 DO CH BY: �" s,e1sM me.
1 � � xp2et� l 800 922 1987 tie 7Gfi'i'I�eae8i _� GRD-524 05
'_ _ _ _ . III I \ .T\ \ / 534-6700 w YS IN otminat0VANCE CHECKED BY: '� SHEET
(lu ® vu zYOU W. a s CIR CI xC(CAWI A
I l ® \ \ FOUR Tt��iux° W.
01c of EUNDEPOPOUND CHECKED BY: 4 Of 13
�---,_ 30' �� i0' -� 1 House i