HomeMy WebLinkAboutDrainage Reports - 10/23/1998UFO
0 (PROPERTY OF
FORT COII.UNS UTnMPM roved Re
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O , .
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� � O
OO Preliminary Drainage and
O O Erosion Control Study
For�the Proposed Addition to the
Orthopedic Clinic of the Rockies
\ O
�) O Fort Collins, Colorado
D Oo
D O OO O 0 Revised
October 9, 1998
r`O O O
O o O
I
Prepared for:
Client:
Neenan
Fort Collins, Colorado 80525
Prepared by:
The Sear -Brown Group
209 S. Meldrum
Fort Collins, Colorado 80521
(303) 482-5922
SBG Job No. 033-025
.+yr
THE
SEAR -BROWN
GROUP
Standards in Excellence
THE SEAR BROWN GROUP
FULL -SERVICE DESIGN PROFESSIONALS
' FORMERLY RBD, INC.
209 SOUTH MELDRUM
' FORT COLLINS, COLORADO 80521-2603
970-482-5922 FAX: 970-482-6368
October 9, 1998
Basil Hamden
'
City of Fort Collins Utilities
700 Wood Street
'
P.O. Box 580
Fort Collins, Colorado 80522
RE: Preliminary Drainage and Erosion Control Study
Proposed Addition to the Orthopaedic Clinic of the Rockies
Dear Basil:
We are submitting to you, for your review and approval, this
' revised Preliminary Drainage and Erosion Control Study for the
Proposed Addition to the Orthopaedic Clinic of the Rockies. All
computations within this report have been completed in
compliance with the City of Fort Collins Storm Drainage Design
Criteria.
We appreciate your. time and consideration in reviewing this
submittal. Please call if you have any questions.
Respectfully,
The Sear -Brown Group, Inc.
Prepared by:
Frederick C. Ernst, E.I.T.
Design Engineer
NEW YORK • PENNSYLVANIA
COLORADO•UTAH
STANDARDS IN EXCELLENCE
Reviewed by:
Kevin W. Gingery, P.E.
Water Resources Manager
EQUAL OPPORTUNITY EMPLOYER
TABLE OF CONTENTS
I.
GENERAL LOCATION AND DESCRIPTION
1
A.
LOCATION
1
B.
DESCRIPTION OF PROPERTY
1
II.
DRAINAGE BASINS
1
A.
MAJOR BASIN DESCRIPTION
1
III.
DRAINAGE DESIGN CRITERIA
2
A.
REGULATIONS
2
B.
DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS
2
C.
HYDROLOGICAL CRITERIA
2
D.
HYDRAULIC CRITERIA
2
E.
VARIANCES FROM CRITERIA
2
F.
FEMA FLOODPLAIN
3
IV.
DRAINAGE FACILITY DESIGN
3
A.
GENERAL CONCEPT
3
V.
EROSION CONTROL
4
A.
GENERAL CONCEPT
4
B.
SPECIFIC DETAIL
4
VI. CONCLUSIONS
5
A. COMPLIANCE WITH STANDARDS
5
B. DRAINAGE CONCEPT
5
C. EROSION CONTROL CONCEPT
5
REFERENCES
6
APPENDIX
7
VICINITY MAP
8
SITE HYDROLOGY
9
STORM SEWER PIPE DESIGN
10
INLET DESIGN
11
EROSION CONTROL PLAN
12
FLOODPLAIN USE PERMIT
13
I
�J
Preliminary Drainage and
Erosion Control Study for the Proposed Addition to the
Orthopaedic Clinic of the Rockies
GENERAL LOCATION AND DESCRIPTION
A. Location
The proposed site is located in the SW
1 /4 of Section 17
Township 7 North, Range 68 West of the
6Lh Prime Meridian,
'
Larimer County. The site is bounded on the
North by the Spring
Creek drainage, on the East by Sharp Point
Drive, on the South
by the East Prospect Road and on the West
by the Orthopaedic
Clinic of the Rockies. The site consists of
approximately 3.26
acres and is located in the Poudre River Basin, near the
confluence of Spring Creek and the Cache
la Poudre River. A
location map is included in the Appendix of this
report.
B. Description of Property
This property consists of the area designated for the Phase II
eastward expansion of the Orthopaedic Clinic of the Rockies.
The area of the site immediately adjacent to the existing building
is paved and slopes away to the east at approximately 2%.
Continuing to the east and north a large mowed natural
vegetated field sloped at approximately 0.5% fills out the
remainder of the site.
Two swales are in place to provide conveyance for runoff from
the existing infrastructure. These swales are located adjacently
to the proposed expansion with one running along the north
boundary and the other running south to north out in the east
field.
The proposed redevelopment will be connected structurally to
the existing buildings.
' II. DRAINAGE BASINS
A. Major Basin Description
The site is located within the Poudre River Drainage Basin. No
major drainage ways exist within the site.
DRAINAGE DESIGN CRITERIA
A. Regulations
The City of Fort Collins Storm Drainage Design Criteria was
followed for the preparation of this report.
B. Development Criteria Reference and Constraints
No stormwater detention will be incorporated into the drainage
concept for this site due to its close proximity to Spring Creek.
Stormwater has historically been routed from the existing site
'
around the proposed addition via two earthen swales that
discharge into Spring Creek. The two swales are located
adjacently north and south of the proposed addition.
'
A 40- hour water quality detention time is being facilitated by a
small gabion check dam at the north end of the swale located in
the east field. The swale is being widened for approximately
175 feet at north end to accommodate the water quality control
'
volume.
C. Hydrological Criteria
The rational method for determining surface runoff was used for
the project site. The 10 and 100-year storm event criteria,
obtained by the City of Fort Collins, were used in calculating
runoff values. These calculations and criteria are included in the
Appendix.
' D. Hydraulic Criteria
All hydraulic calculations within this report have been prepared
' in accordance with the City of Fort Collins Drainage Criteria and
are included in the Appendix.
1
E. Variances from Criteria
No variances from City of Fort Collins Storm Drainage Criteria
are being sought for this project.
1� 2
1
F. FEMA Floodplain
The project site is located within the FEMA 100-year flood plain
'
of the Cache la Poudre River. The currently effective Flood
Insurance Rate Maps indicate that the base flood elevation for
the project site is 4900.0 feet. Therefore, the proposed building
will be elevated 1.50' above the base flood elevation. A
'
completed Floodplain Use Permit Application is included in the
Appendix of the report.
IV. DRAINAGE FACILITY DESIGN
'
A. General Concept
'
The site lies in Zone AE of the FEMA Flood Insurance Rate Map,
Community -Panel Number 080102.0012 C. The finished floor
of the proposed addition has been set at.4901.5, which is the
same elevation of the finished floor of the existing structure.
These finished floor elevations are 1.5 feet above the base flood
'
elevation of 4900 ft.
Stormwater for the proposed expansion will be collected from
the roof in roof drains and allowed to surface flow on to the
proposed parking area in Basins 1 and 2 via three 2-foot
concrete pans. The eastern boundary of the parking area of the
expansion will not have curb and gutter. The storm flows for
Basin 1 will be allowed to sheet flow across the parking surface
and into the grassy area to the east. Flows will then be
intercepted by the eastern existing drainage swale that runs to
the north.
' Erosion control fabric along with 1-foot deep cutoff walls have
been placed at the termination points of the inflow curb and
' gutter at the east ends of the parking lot in Basin 1 to help
prevent slope erosion and gutter undermining. The flows for
these erosion control calculations were determined by weighting
' the total 100-year flow from Basin 1 with the tributary area of
these termination points.
The existing drainage swale has been resized to accommodate
the additional flows from the development, which are 11.16 cfs
for the 10-year event, and 24.08 cfs for the 100-year event.
Please see the normal depth calculations showing the 10-year
1 3
11
1
I
I
1
F
V
I
1
and 100-year channel depths for the reconfigured swale. The
flow velocities in the swale for the 100-year event are 1.46 ft/s
for the portion south of the two existing 12-inch culverts, and
0.95 ft/s for the northern portion. These relatively low velocities
do not require that the swale be armored for erosion.
The small storm flows for Basin 3 will be allowed to sheet flow
across the parking surface and into the grassy area to the north.
An area inlet has been placed in the cross -pan at the new
proposed entrance to capture nuisance flows and accommodate
the 10-year rainfall event of 2.17 cfs for Basin 2. This inlet is
being placed in line with the current 15" RCP drainage system.
Basins OS1 and OS2 provide the tributary area for the two
existing inlets that discharge into the existing storm sewer. This
system subsequently discharges into the south swale.
Water quality capture volume requirements are also being
addressed within the eastern swale. The swale has been
widened at its north end to realize a capture volume of 0.047
acre-feet. The 40-hour drain time is being facilitated by a 1-foot
high filter wrapped gabion dam structure at the north end of the
swale. Please see the pond rating curve calculations that show
the storage volume provided within the contours of the widened
swale.
EROSION CONTROL
A. General Concept
The proposed site is located in the low wind and low rain
erodibility zones per the City of Fort
Collins zone maps. In accordance with the City of Fort Collins
Erosion Control Reference Manual for Construction Sites, the
erosion control performance standard is 76.1 % during
construction and 89.5% after construction. The erosion control
specified on the Drainage and Erosion Control plan will result in
a performance standard during construction of 79.3% and
93.3% after construction. criteria from the City of Fort Collins
Storm Drainage Design Criteria Manual were implemented for
this project. Please see the Erosion Control Plan included in the
Appendix.
B. Specific Detail
M
' Upon the commencement of over -lot grading a silt fence must
be constructed along the north, east and south border of the
construction zone. A gravel inlet filter is to be installed around
the area inlet located in the proposed entrance. A straw bale
' check dam will be used at the end of the proposed swale for
sediment control. The roads shall be gravel mulched and all
other areas shall be hay mulched and seeded. The estimate of
Ithe escrow account for erosion control is $3,005.
�II
�J
VI. CONCLUSIONS
' A. Compliance with Standards
All computations that have been completed within this report
are in compliance with the City of Fort Collins Storm Drainage
' Design Criteria Manual.
B. Drainage Concept
The proposed drainage concepts adequately provide for the safe
transmission of stormwater flows off the proposed addition to
the Orthopaedic Clinic of the Rockies site. Drainage detention
and routing methods were employed to ensure that the
historical flow condition from the site was not adversely
affected, and that water quality issues concerning Spring Creek
were addressed.
C. Erosion Control Concept
The proposed erosion control plan provides adequate control of
wind and rainfall erosion from the proposed addition to
Orthopaedic Clinic of the Rockies site. Suggestions for the
erosion control structures used on this project were taken from
the Storm Drainage Design Criteria and Construction Standards
by the City of Fort Collins, May 1984.
L
1 5
1
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1
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REFERENCES
1. Storm Drainage Design Criteria and Construction
Standards by the City of Fort Collins, Colorado, May
1984 revised March 1991.
2. Federal Emergency Management Agency, Flood Insurance
Rate Map, City of Fort Collins, Colorado, Larimer County,
Community — Panel Number 080102.0012 C, Revised
March 18, 1996.
3. Stormwater Quality Management, Section 5.4, Urban
Storm Drainage Criteria Manual, Volume 3 — Best
Management Practices, Urban Drainage and Flood Control
District, Denver, Colorado.
0
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1
APPENDIX
1
F
7
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1
1
1
Vicinity Map
F3
1
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1
1
1
1
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1
1
1
1
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17
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VICINITY MAP
SCALE:1"=1000'
I
1
I
1
Site Hydrology
1
1
11
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Water Quality Capture Volume (WQCV)
WQCV =I Re quiredStor ageJ l (Area 12 J
WQCV = water quality capture volume in acre-feet.
RequiredStorage = Required storage in watershed inches (Figure 5.1).
Area = The tributary drainage area upstream of the water quality enhancement facility.
Re/erence:
Stormwater Quality Management, Section 5.4
Urban Storm Drainage Criteria Manual
Volume 3 - Best Management Practices
Urban Drainage and Flood Control District
Denver, Colorado
I
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OCR Expansion
Project No.033-025
Detention Pond Volume Rating Curve
93.87
0
0.00
0.000
94.00
725
0.02
0.001
95.00
8,065
0.19
0.086
Water Quality WSEL =
V= Id(A+B+ AB)
where:
V = volume between contour interval
d = elevations - elevation,-,
A = area of elevation., contour
B = area of elevation contour
0.000
0.001
0.086
Volume Required =
0.048
acre-ft.
Water Surface Area =
0.16
acre
Volume Provided =
0.067
acre-ft.
11:21 AM
The Sear -Brown Group 9129/98
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Storm Sewer Pipe Design
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THE
SEAR -BROWN
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Protect: ProJect No.
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STORM SEWER SYSTEM DESIGN USING UDSEWER MODEL
__--_------ Developed Civil Eng. Deets U. Colorado at Denver-_____------
Metro Denver
r Cities/Counties 8 UD FCD Pool Fund Study
USER:RDB-Fort Collins -Colorado ...............................................
ON DATA 10-09-19911 AT TIME 09:13:32 VERSION=01-17.1997
**' PROJECT TITLE :OCR Expansion - Storm 1
'•• RETURN PERIOD OF FLOOD IS 10YEARS
(Design flow hydrology not calculated using UDSEWER)
*** SUMMARY OF HYDRAULICS AT MANHOLES
___________________________________________________________________________
MANHOLE CNTRBTING RAINFALL RAINFALL DESIGN GROUND WATER COMMENTS
ID NUMBER AREA * C DURATION INTENSITY PEAK FLOW ELEVATION ELEVATION
MINUTES
_______________________________________________________________________________
INCH/HR
CFS FEET
FEET
1.00
7.00 96.35
97.30
NO
2.00
7.00 99.56
98.20
OK
3.00
7.00 99.42
98.84
OK
4.00
4.83 99.96
99.14
OK
5.00
3.14 99.72
99.40
OK
'
6.00
3.14 99.72
99.57
OK
OK MEANS WATER ELEVATION IS LOWER
THAN GROUND ELEVATION
*" SUMMARY OF SEWER HYDRAULICS
'
NOTE: THE GIVEN FLOW DEPTH
-TO -SEWER SIZE
_____________________________________________________________________
RATIO= .8
SEWER MANHOLE NUMBER
SEWER
REQUIRED SUGGESTED
EXISTING
ID NUMBER UPSTREAM DNSTREAM
SHAPE
DIA(RISE) DIA(RISE) DIA(RISE)
WIDTH
----'_'_------ID NO. ID NO --•---------(IN)
--- ________
(FT) (IN) (FT) (IN) (FT)
(FT)
12.00 2.00 1.00
ROUND
---- _---- _---- _----
20.46 21.00
_---- _____----
18.00
0.00
23.00 3.00 2.00
ROUND
19.58 21.00
18.00
0.00
'
34.00 4.00 3.00
ROUND
17.04 18.00
15.00
0.00
45.00 5.00 4.00
ROUND
14.50 15.00
15.00
0.00
56.00 6.00 5.00
ROUND
14.50 15.00
15.00
0.00
DIMENSION UNITS FOR ROUND AND ARCH
SEWER
ARE IN INCHES
'
DIMENSION UNITS FOR BOX SEWER ARE
IN FEET
REQUIRED DIAMETER WAS DETERMINED
BY SEWER
HYDRAULIC CAPACITY.
SUGGESTED DIAMETER WAS DETERMINED BY COMMERCIALLY AVAILABLE SIZE.
'
FOR A NEW SEWER, FLOW WAS ANALYZED BY THE
EXISITNG SIZE WAS USED
SUGGESTED SEWER SIZE;
OTHERWISE,
_______________________________________________________________________________
SEWER DESIGN FLOW NORMAL
NORAAL
CRITIC CRITIC FULL
FROUDE
COMMENT
ID FLOW 0 FULL 0 DEPTH
VLCITY
DEPTH VLCITY VLCITY
NO.
NUMBER CFS CFS FEET
----
FPS
_____---
FEET FPS FPS
12.0 7.0 5.0 1.50
____----
3.96
_____... _______________________
1.02 5.45 3.96
0.00
V-OK
23.0 7.0 5.6 1.50
34.0 4.8 3.5 1.25
3.96
3.94
1.02 5.45 3.96
0.89 5.20 3.94
0.00
0.00
V-OK
V-OK
45.0 3.1 3.5 0.94
3.19
0.71 4.34 2.56
0.59
V-OK
56.0 3.1 3.5 0.94
3.19
0.71 4.34 2.56
0.59
V-OK
'
FROUDE NUMBER=O INDICATES THAT A
PRESSURED FLOW OCCURS
------ _-------- _--------- _---- ___---------
SEWER SLOPE INVERT ELEVATION
_---- _______________________
BURIED DEPTH COMMENTS
'
ID NUMBER UPSTREAM DNSTREAM
X(FT) (FT)
_______________________.
UPSTREAM DNSTREAM
(FT) (FT)
12.00 0.34 96.53
96.35
1.53 -1.50
NO
23.00 0.43 96.95
96.63
0.97 1.43
NO
34.00 0.43 97.10
96.95
1.61 1.22
NO
'
45.00 0.43 97.23
97.10
1.24 1.61
NO
56.00 0.43 98.47
98.47
0.00 0.00
NO
OK MEANS BURIED DEPTH IS GREATER
THAN REQUIRED SOIL COVER OF 2
FEET
FA
' *** SUMMARY OF HYDRAULIC GRADIENT LINE ALONG SEWERS
SEWER SEWER SURCHARGED CROWN ELEVATION WATER ELEVATION FLOW
ID NUMBER LENGTH
LENGTH UPSTREAM DNSTREAM UPSTREAM DNSTREAM CONDITION
'
FEET
-------------------------------------------------------------------------------
FEET FEET FEET FEET FEET
12.00 51.69
51.69 98.03 97.85 98.20 97.30 PRSS'ED
23.00 75.53
75.53 98.45 98.13 98.84 98.20 PRSS'ED
'
34.00 34.25
34.25 98.35 98.20 99.14 98.84 PRSS'ED
45.00 30.00
30.00 98.48 98.35 99.40 99.14 PRSS'ED
56.00 0.10
0.00 99.72 99.72 99.57 99.40 SUBCR
PRSS'ED=PRESSURED FLOW;
JUMP=POSSIBLE HYDRAULIC JUMP; SUBCR=SUBCRITICAL FLOW
SUMMARY OF ENERGY GRADIENT LINE ALONG SEWERS
UPST MANHOLE
SEWER JUNCTURE LOSSES DOWNST MANHOLE
SEWER MANHOLE ENERGY
FRCTION BEND BEND LATERAL LATERAL MANHOLE ENERGY
ID NO ID NO. ELEV FT
FT K COEF LOSS FT K COEF LOSS FT ID FT
_______________________________________________________________________
12.0 2.00 98.44
1.14 0.00 0.00 0.00 0.00 1.00 97.30
23.0 3.00 99.09
0.51 0.56 0.14 0.00 0.00 2.00 98.44
34.0 4.00 99.39
0.29 0.05 0.01 0.00 0.00 3.00 99.09
45.0 5.00 99.50
0.11 0.05 0.01 0.00 0.00 4.00 99.39
'
56.0 6.00 99.67
0.04 1.25 0.13 0.00 0.00 5.00 99.50
BEND LOSS =BEND K* FLOWING FULL VHEAD IN SEWER.
LATERAL LOSS= OUTFLOW FULL VHEAD-JCT LOSS K*INFLOW FULL VHEAD
FRICTION LOSS=O MEANS
IT IS NEGLIGIBLE OR POSSIBLE ERROR DUE TO JUMP.
1
FRICTION LOSS INCLUDES SEWER INVERT DROP AT MANHOLE
NOTICE: VHEAD DENOTES
THE VELOCITY HEAD OF FULL FLOW CONDITION.
A MINIMUM JUCTION LOSS OF 0.05 FT WOULD BE INTRODUCED UNLESS LATERAL K=O.
FRICTION LOSS
WAS ESTIMATED BY BACKWATER CURVE COMPUTATIONS.
iJ
IThe Sear -Brown Group
Riprap Design using UDFCD Methods
' Project: OCR Expansion Designer., JCE
Project M 033-025 Date: 22-Sep-98
' location: Storm 1 Outfall
Pipe dia.: 18 in
Discharge 7 cfs
I
Tailwater. 0.6 ft (variable/unknown)
Max Val.: 2.5 ftls (soil dependent)
1. Required riprap type:
Q/D^2.5 =
2.54 < 6 --> use design charts
D=
1.50 ft
YUD =
0.40
Q/D^1.5 =
3.81
d50 =
6 in
> Use Type L (Class 6) riprap
2. Expansion factor:
1 / [2 tan(theta)] = 4.4
3. Riprap length:
At=ON=
L = 1/[2tan(theta)]'(At/Yt - D) _
4. Governing limits:
L>3D= 5 ft
L<10D= 15 ft
2.80 ft2
14 ft
<= 14 ft --> OK
_> 14 ft --> OK
5. Maximum depth:
Depth = 2d50 = 2 (6 in / 12) = 1 ft
6. Bedding:
' Use 1 ft thick layer of Type II (CDOT Class A)
bedding material.
' 7. Riprap width:
Width = 3D = 3 (18 in /12) _
Summary.
Type L (Class 6) riprap
Length = 14 ft
Depth = 1 ft
' Width = 5 ft
Bury with 6 inches topsoil.
1
1
5ft
' 22-Sep-98
' South Swale Section 100 yr. Cross Section
Cross Section for Trapezoidal Channel
eProject Description
Project File
c:\haestad\fmw\ocr expa.fm2
Worksheet
Storm 1
'
Flow Element
Trapezoidal Channel
Method
Manning's Formula
Solve For
Channel Depth
Section Data
Mannings Coefficient
0.060
Channel Slope
0.005200
ft/ft
Depth
1.59
ft
Left Side Slope
4.000000
H : V
Right Side Slope
4.000000
H : V
Bottom Width
5.00
ft
'
Discharge
32.02
cfs oc + A's
I
q /1
'
1.59 ft
1
5.00 ft
V
H 1
NTS
I
'09/29/11 FlowMaster v5.15
11:38:24 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755.1666 Page 1 of 1
' South Swale Section 100 yr.
Worksheet for Trapezoidal Channel
' Project Description
Project File
c:\haestad\fmw\ocr expa.fm2
Worksheet
Storm 1
Flow Element
Trapezoidal Channel
Method
Manning's Formula
'
Solve For
Channel Depth
Input Data
'
Mannings Coefficient
0.060
Channel Slope
0.005200 ft/ft
Left Side Slope
4.000000 H : V
'
Right Side Slope
4.000000 H : V
Bottom Width
5.00 ft
Discharge
32.02 cfs
Results
Depth
1.59 ft
Flow Area
17.99 ft'
Wetted Perimeter
18.08 ft
'
Top Width
17.69 ft
Critical Depth
0.86 ft
Critical Slope
0.063343 ft/ft
Velocity
1.78 ft/s
'
Velocity Head
0.05 ft
Specific Energy
1.64 ft
Froude Number
0.31
'
Flow is subcritical.
1
'119/29/98 FlowMaster v5.15
11:33:08 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1
' North Swale Section 100 yr. Cross Section
Cross Section for Trapezoidal Channel
' Protect Description
Project File
c:\haestad\fmw\ocr expa.fm2
Worksheet
Storm 1
'
Flow Element
Trapezoidal Channel
Method
Manning's Formula
'
Solve For
Channel Depth'
'
Section Data
Mannings Coefficient
0.060
Channel Slope
0.003800
ft/ft
Depth
0.92
ft
'
Left Side Slope
10.000000
H : V
Right Side Slope
10.000000
H : V
Bottom Width
20.00
ft
'
Discharge
32.02
cfs = (;�`oo -V 133
I
20.00 ft v N
H1
NTS
'19/29/91 FlowMaster v5.15
11:39:07 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1
1
' North Swale Section 100 yr.
Worksheet for Trapezoidal Channel
' Project Descnptlon
Project File
c:\haestad\fmw\ocr expa.fm2
Worksheet
Storm 1
'
Flow Element
Trapezoidal Channel
Method
Manning's Formula
Solve For
Channel Depth
Input Data
'
Mannings Coefficient
0.060
Channel Slope
0.003800 ft/ft
Left Side Slope
10.000000 H : V
'
Right Side Slope
10.000000 H : V
Bottom Width
20.00 ft
Discharge
32.02 cfs
Results
Depth
0.92 ft
Flow Area
26.72 ft'
Wetted Perimeter
38.42 ft
Top Width
38.32 ft
'
Critical Depth
0.40 ft
Critical Slope
0.075039 ft/ft
Velocity
1.20 ft/s
'
Velocity Head
0.02 ft
Specific Energy
0.94 ft
Froude Number
0.25
'
Flow is subcritical.
I
I
J
'09/29/98 FlowMaster v5.15
11:28:05 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1
************************************************************************
NORTH AMERICAN GREEN CHANNEL PROTECTION
MATERIAL SPECIFICATIONS
�350 Specification
North American Green C350 permanent erosion control/turf
reinforcement mat is constructed of 100% coconut fiber stitch bonded
between a heavy duty UV stabilized bottom net, and a heavy duty UV
stabilized cuspated (crimped) middle netting overlaid with a heavy
duty UV stabilized top net. The cuspated netting forms prominent
closely spaced ridges across the entire width of the mat. The three
nettings are stitched together on 1.5 in (3.8 cm) centers with UV
stabilized polypropylene thread to form a permanent three dimensional
structure. The following list contains further physical properties
of the C350 Erosion Control/Turf Reinforcement Mat.
Property
Ground Cover
Thickness
Mass Per Unit Area
Tensile Strength
Elongation
Tensile Strength
Elongation
Tensile Strength
Elongation
Resiliency
UV Stability*
Test Method
Image Analysis
ASTM D1777
ASTM D3776
ASTM D5035
ASTM D5035
ASTM D5035
ASTM D5035
ASTM D1682
ASTM D1682
ASTM D1777
ASTM D4355
Color(permanent net)
Porosity(permanent net) Calculated
Minimum Filament Measured
Diameter (permanent net)
Value
93
.63 (1.6)
.92 (.50)
480 (714)
49
960 (1429)
31
177 (80)
22
>80
151 (68)
86
UV Black
>95
.03 (.08)
Unit
in (cm)
lb/sy (kg/m-2)
lb/ft (kg/m)
lb/ft (kg/m)
lbs (kg)
lbs (kg)
in (cm)
*ASTM D1682 Tensile Strength and % Strength Retention of material
after 1000 hours of exposure in Xenon -Arc Weatherometer
Physical Specifications (Roll)
Width 6.5 feet (2 m)
Length 55.5 feet (16.9 m)
Weight 37 lbs +/- 10% (16.8kg)
Area 40 yd"2 (33.4 m-2)
11
Oisdwge
ds
Peak Flow
Petiad s
Vek'ciy Dpsj
Area(w.tt.1
Rydiaiic
R k
Nanal
D k
.0
1.0
1 Z22
1 0.45
1 0.11
1 015
4200 W zmk �.d
Not to Scale
Reach
MatwiaT
Phase
V Type
Soi Type
Mamig's'n
Pnmissbk
Sheat Shess 1psfl
Cab"ed
Shen Saes$ Ix0
Safety
Facto
Renwke
St ePattem
Class
V .Demt
Shari
C350
2
0.D44
6.00
0.75
7.95
STABLE
Slaps
DefnA
I
I
NORTH AMERICAN GREEN EROSION CONTROL MATERIALS DESIGN SOFTWARE VERSION 4.1
ORTH AMERICAN GREEN CHANNEL PROTECTION - ENGLISH/S.I.
SER SPECIFIED CHANNEL LINING BACK-UP COMPUTATIONS
****************************************************************************
RROJECT NAME: OCR Expansion
COMPUTED BY: FCE
`ROM STATION/REACH: 0
RAINAGE AREA: 7000 ft-2
PROJECT NO.: 033-025
DATE: 9/22/98
TO STATION/REACH: 25
DESIGN FREQUENCY: 100-year
****************************************************************************
INPUT PARAMETERS
****************************************************************************
hannel Discharge
eak Flow Period
Channel Slope
hannel Bottom Width
eft Side Slope
ight Side Slope
: 1.0 cfs (.
: 1 hours
: 0.08 ft/ft
: 2.0 ft (.61
12:1
1:1
hannel Lining : C350 Staple E
Permi. Shear(Tp):6.00 psf (287
Phase = 2
03 m"3/s)
(0.08 m/m)
m)
Pa)
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
CALCULATIONS
Intial Depth Estimate = 0.16*(1.0 /(0.080-0.5))-0.375 = 0.26 ft (.08 m)
inal Channel Depth (after 10 iterations) _ .15 ft (0.05 m)
low Area = (2.0 * 0.2)+(0.5 *0.15^2 * (12.0+1.0)) = 0.5 sf (0.0 m"2)
et Per. =2.0 +(0.2*(((12.0-2)+1)-.5 +((1.0-2)+1)-.5)) = 4.0 ft (1.2 m)
Hydraulic Radius = (0.5 / 4.0) = 0.1 ft (0.0 m)
Ihannel Velocity=(1.486/0.044)*(0.1-0.667)*(0.080-.5) = 2.2 fps (0.7 m/s)
Channel Effective Manning's Roughness = 0.044
�alculated Shear (Td) = 62.4 * 0.15 * 0.080 = 0.75 psf (36.1 Pa)
afety Factor = (Tp/Td) _ (6.00 /0.75) = 7.95
STAPLE PATTERN "E"
1 3.8 staples/yd^2 (4.5
staples /m^2) using 6 in
(15.2 cm), 11 ga. wire "U" 4
1 staples. 8 in (20.3 cin) (1
staples and longer may be
used for loose soils. 9
1 ga. staples or heavier may
be necessary in hard or
rocky soils.
1 10
1 (25.4
1
NORTH
1 �
1
1
i
1
1
1
F
1
1
I
1
I
1
11
I
I
1
Inlet Design
1
11
Area Inlet Design • Sump Condition
OCR Expansion
Project No. 033-025
This sheet displays the controlling area Inlet flow condition.
Weir Equation:
n
Q o =CLH2
where: H = head above weir
Orifice Equation:
Qe,n = C. A. 2gH
where: H= h t- h r
Grate: (Neenah R-3382)
Weir:
Orifice:
C,... = 2.80
C. = 0.6
Lv.0 = 1.75 k (1)
Aar = 2.33 ft"
Oog Ing Factor= 0.50
Flowline elevation of grate =
99.42
10 year Design Flow lots) =
2.17
10 year WSEL (2.17)=
100.00
100 year Design Flow, (cfs) =
4.05
100 year WSEL (4.05) =
100.29
Head (ft.)
0.1
O„.,m
0.
WSEL
0.00
0.00
0.00
0.00
99.42
0.50
1.73
3.97
1.73
99.92
1.00
4.90
5.61
4.90
100.42
1.50
9.00
6.87
6.87
100.92
2.00
13.86
7.94
7.94
101.42
2.50
19.37
8.87
8.87
101.92
3.00
25.46
9.72
9.72
102.42
3.50
32.08
10.50
10.50
102.92
4.00
39.20
11.22
11.22
103.42
4.50
46.78
11.91
11.91
103.92
5.00
54.78
12.55
12.55
104.42
Notes:
1) This is the effective weir length which equals the sum of the open space lengths between
bars in the predominant flow directions.
The Sear -Brown Group
11:17 AM
9/22198
I
1
1
I
I
1
Erosion Control Plan
12
' The Sear -Brown Group
' RAINFALL PERFORMANCE STANDARD EVALUATION
#033-025
1
11
I
Project: O.C.R. Expansion STANDARD FORM
Calculated By. tld Date: 08/31
DEVELOPE
ERODIBILIT
Asb
Lsb
Ssb
Lb
Sb
PS
SUBBASIN
ZONE
(ac)
(ft)
(%)
(ft)
(%)
(%)
1
low
2.89
450
1.6
412.9
1.5
2low
0.26
185
0.7
15.3
0.1
Total
3.15
428.1
1.5
79.3
IWA.1LTA IJ■:01G1[Xltly\rLei .61
Lb = sum(AiLi)/sum(Ai) = (2.89 x 450 + ... + 0.26 x 185)/ 3.15
'
428.1 ft
Sb = sum(AiSi)/sum(Ai) = (2.89 x 1.60 + ... + 0.26 x 185.00)/ 3.15
1.5 %
PS (during construction) = 79.3
IPS (after construction) = 79.3/0.85 =
11
(from Table 8A)
93.3
IThe Sear -Brown Group
1
1 #033-025
i
Ir J
I
1
1
I
I
I
1
1
1
i
i
1
I
EFFECTIVENESS CALCULATIONS
Project: O.C.R. Expansion STANDARD FORM B
Calculated By. tld Date: 08/31
Erosion Control
C-Facto
P-Facto
Comment
Number Method
Value
Value
3 Bare Soil - Rough Irregular Surface
1
0.9
4 Sediment/Basin Trap
1
0.5
8 Silt Fence Barrier
1
0.5
12 Established Grass Ground Cover - 30%
0.15
1
38 Gravel Mulch
0.05
1
39 Hay or Straw Dry Mulch (1-5% slope)
0.06
1
SUB
PS
AREA
BASIN
N
(ac)
Site
79.3
3.15
SUB
SUB
AREA
Practice C * A P * A Remarks
BASIN
AREA
(ac)
DURING CONSTRUCTION
1
PERVIOUS
1.83
39 0.11 1.83 Hay or Straw Dry Mulch (1-5% slope)
1
IMPERVIOUS
1.06
38 0.05 1.06 Gravel Mulch
2
PERVIOUS
0.00
3 0.00 0.00 Bare Soil - Rough Irregular Surface
2
IMPERVIOUS
0.26
38 0.01 0.26 Gravel Mulch
Cnet = [1.83x1.00+...+0.26x1.00]/1.83
= 0.06
Pnet = 0.8x[1.83x0.50+...+0.26x0.50]/1.83
= 0.80
EFF = (1-C*P)100 = (1-0.06*0.80)100
= 95.54
> 79.3 (PS)
1
' The Sear -Brown Group
EFFECTIVENESS CALCULATIONS
11
1
d
I
i�
#033-025
Project: O.C.R. Expansion STANDARD FORM B
Calculated By.- tid Date: 08/31
Erosion Control
C-Facto
P-Facto
Comment
Number Method
Value
Value
9 Asphalt/Concrete Pavement
0.01
1
14 Established Grass Ground Cover - 50%
0.08
1
16 Established Grass Ground Cover - 70%
0.04
1
18 Established Grass Ground Cover - 90%
0.025
1
SUB
PS
AREA
BASIN
(%
(ac)
Site
93.3
3.15
SUB
SUB
AREA
Practice C *A P * A Remarks
BASIN
AREA
(ac)
AFTER CONSTRUCTION
1
PERVIOUS
1.83
16 0.07 1.83 Established Grass Ground Cover - 70
1
IMPERVIOUS
1.06
9 0.01 1.06 Asphalt/Concrete Pavement
2
PERVIOUS
0.00
14 0.00 0.00 Established Grass Ground Cover - 50
2
IMPERVIOUS
0.26
9 0.00 0.26 Asphalt/Concrete Pavement
Cnet = [1.83x0.08+...+0.00x0.08y1.83
= 0.03
Pnet = [1.83x1.00+...+0.00x1.00]/1.83
= 1.00
EFF = (1-C*P)100 = (1-0.03*1.00)100
97.26
> 93.3 (PS)
' The Sear -Brown Group
' EROSION CONTROL CONSTRUCTION SEQUENCE
#033-025
' Project: O.C.R. Expansion
Calculated By.- lid
SEQUENCE FOR 1998 ONLY
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 98
'MONTH A S O N I D J F
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
VEGETATIVE:
Permanent Seed Planting
Mulching/Sealant
Temporary Seed Planting
Sod Installation
' Neftings/MatsBlankets
Other
STRUCTURES: INSTALLED BY _ MAINTAINED B
VEGETATION/MULCHING CONTRACTOR
' DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS
1
FORM
' The Sear -Brown Group
EROSION CONTROL COST ESTIMATE
Project: O.C.R. Expansion
#033-025
Prepared By. tld
Date: 08/31
GITY RESEEDING COST
unit
Total
Method Quantity Unit
Cost
Cost Notes
Reseed/mulch 3.15 ac
$636
$2,003 See Note 1.
Subtotal
$2,003
Contingency
50%
$1,002
Total
$3,005
Notes: 1. A<=5 ac=$636/ac; A>5 ac=$531/ac.
' EROSION CONTROL MEASURES
Number Method Qua
This section is no longer required per Bob Zackley
9
Subtotal
Contingency
Total
'
Total Securit
Unit
Unit Total
Cost Cost
50%
$0
005
Notes
I
J
Floodplain Use Permit
13
r'-
FLOODPL AIN USE PERVIIT
City of Fort Collins Code, Section 10-37
(Attach application, fief oj5?5.00. IjJloodplain analysis required fife is 5300.00)
PETITIONER NAME:
'
r
ADDRESS:_ ( -J '� c r �,Z s :>:-- .•� . PHONE: '4G13 -
'
OWNERNAME: 5C- t IlnoM=S
1
ADDRESS: ? ;=� �'� ,�l• PHONE: t 73-OIl�
'
LEGAL ADDRESS AND/OR ADDRESS OF PROPERTY:
'
DESCRIPTION OF PROPOSED USE(resider,:iaL'commerciaL/accessory structure/substantial
improvement'fill-excavation'other). STRUCTURE ELEVATED,FLOODPROOFED? IF
FLOODPROOFED DESCRIBE METHOD USED. r 7 ;. -,=... ; , _ ',Pf `• : ry _'-•,�
EXISTING GROUND ELEV: JI.90M.S.L. FINISHED GROUND ELEV:49Dt.5'D M.S.L
'
LOWEST FLOOR ELEV (INCLUDING BASEMENT): M.S.L.
BASE FLOOD ELEVATION (BFE): FIRM "J J. MASTER PLAN BFE
REGULATORY FLOOD ELEVATION (BFE=1.5') 49of • O
'
FLOODPLAIN NAME, fOUA3 G (2� `FLOODWAY (Y/N) iV
"VARIANCE FROM ORDINANCE (YrN) (if yes, attach variance application with
'
additional S300 variance fee -City Code, Section 10-38)
FLOODPLAIN USE PERMIT:
' SIGNATURE OF
DENIED
ATE a Ze( 0 a
' SIGNATUREOFOWNER
SS ,-�M Ice
1,-a V1 ' J-A ✓ L�� DATE 8-29-98
GF1AY'MEDl�aAL�'SERVICES LLC
SIGNATURE OF FLOODPLLLLLLA ADMINI TRaT R DATE
1
'I
' If property located in Iloodway include technical evaluation that demonstrates "no -rise" City Code 10-55.
"Variance application can be obtained from the Stormwater Utility. Variance request requires hearing by
Storm Drainage Board.
LEGEND
99 PROPOSED INTERMEDIATE CONTOUR
—00— PROPOSED INDEX CONTOUR
PROPDGED SPOT ELEVATION
•_ np
v O FLOWIINE UNLESS OTHERVIISE NOTED
----u94— -' EXISTING INTERMEDATE CONTOUR
--M95— EXISTING INDEX CONTOUR
City of Fort Collins, Colorado
UT11M PLAN APPROVAL
APPROVED:
BLeetor of 66duaen°6 NIA
CHECKED BY:
Ietm t Iut••dm ULWty Dine
CHECKED BY:
Btmmntcr Utility Date
CHECKED BY:
Puri k RNumllu Duce
CHECKED BY:
— — — —
— y
— I CHECKED BY:
SALE P_36 ••�...� -__ ____.___ -�—� /
CONTROL PONT ARC•E E'drnNC' EXISTING -STORAGE
-...._.. l N6BBJ6_ b TNASIL EIEU'LOSURE .SHED REMAIN \ -.
— — E 640.58 r IIASEBALL BACKSTOW
La-
•-rp
` _ b9e- - _ _ � � `Tp BE RELOCATED `. — •_ _ _
wes
I u
/ I - 9 - - I 97
EXIS➢NG CORNER
PROPOSED INFALL CURB qqq I
_-- r PP
��
h , / CA LION I DABION CHECK
DAM
IrZ
Y RAMP
G -
RE. - 6601.50 I /
CONTROL PqN
E 999.02
EXISTING CgENEft
N A8.15 0
eCURB UGjTyCR
--- s s 9MN—
Exl�/I
C o µP /LITY
STING U TO
} STOP A EELM TO BE
9Q! I N RECOIL D
�_..`RAMP_ _ ING
1� T 2PVC PIPE
s'
RIPRAP PAD
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ONTROL POINT
N 28IL"
5' E 75x.29
Ev % seM
RE LOCAMID sAN: �sArv�
LOCATION, L —! �Y8 =i r SKIN YW
1RW TQ_kWAHN, AT MANHOLE " TO REMAIN AT E �SArv--
.8 EIjV. 40Q.W-- -EXISTING ELEV. - 9920 �SAN� _
`fe" SAL
IS
-4899-
— — — ---_
�_ — — 1
RIND EIEC VAULT
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PRO<R NO,
033-025
ORAWNG NO.
4a