HomeMy WebLinkAboutDrainage Reports - 11/07/2002SEAR BROWN
November 6, 2002
Mr. Glen D. Schlueter
City of Ft. Collins
700 Wood Street
Ft. Collins, CO 80522
ARCHITECTURE
ENGINEERING
PLANNING
CONSTRUCTION
209 South Meldrum
Fort Collins,CO 80521
970.482.5922 phone
970.482.6368 fax
www.searbrownxom
FInal Ap roved Report
Date /i-7-az
RE: FINAL ABBREVIATED DRAINAGE REPORT FOR THE CENTRE FAMILY
DENTISTRY — CENTRE FOR ADVANCE TECHNOLOGY,10 FILMQ
Dear Glen:
This abbreviated drainage report is provided in response to Lockwood Architect's request for
drainage analysis associated with the proposed addition of the Centre Family Dentistry office at
the existing Centre For Advanced Technology 10°i Filing (CAT). Specifically, the proposed
addition will be located at CAT 10th Filing, in the South half of Section 23, Township 7 North,
Range 69 West of the 6`h P.M., in the City of Ft. Collins, Larimer County, Colorado. More
generally, the Project would be an addition off an existing structure located just south of Centre
Avenue and west of Worthington Circle.
The approved and recorded Site Plan (SBG, 1990) shows a 7,000 square foot building envelope.
However, the existing structure is approximately 4,000 square feet. Currently, there exists a
detention pond facility in the southeast area of the subject property designed to accommodate the
previously planned and approved building envelope of 7,000 square feet as well as ancillary
parking.
The proposed addition is up to 600 square feet, and would extend beyond the existing building
envelope, possibly displacing up to three parking stalls. Sidewalk connections would be
maintained to the greatest extent possible. Under current developed site conditions the proposed
addition would occupy up to approximately 4,600 square feet. In the event that the Owner
proceeded with the originally planned and approved envelope area plus the 600 square foot
addition, the total area would sum to about 7,600 square feet. The analysis presented herein
considers the most conservative case of a fully built 7,600 square foot building structure.
To remain consistent with past Site analysis and City stormwater guidelines, the analysis
contained here uses Rationale Method factors associated with weighted runoff coefficients
("CCf"), current City rainfall data as applied to entire Site, and the FAA Detention Pond Method.
Beyond the proposed addition and ancillary minor improvements (i.e. landscaping, parking
reconfigurations, etc.) the Site will essentially remain the same. Drainage will flow south through
the Project to an existing detention pond, where it will be attenuated and released at the originally
approved rate of 0.68 cfs to the Centre Avenue storm drainage system which conforms to the
Drainage Report for the Centre for Advanced Technology Special Improvements District,
February 1987, RBD, Inc. Engineering Consultants.
For informational purposes, Site details for the originally approved Lot 3 layout and proposed
conditions are tabulated below showing the relative changes that are used for drainage analysis of
the proposed addition.
TARTY I - Lot 3 — As Originally Annroved (Excludes Pond Areal
Feature
Area Acres
Area (Square Feet
Percent Area
Total Land
0.737
32,124.00
100.0
Building
0.149
7,000.00
21.8
Drives & Parking
0.321
13,999.75
43.6
Sidewalks
0.034
1,483.00
4.6
Landscaping
0.233
1 9,641.25
30.0
TABLE 2 - Lot 3 — As Oriinally Annroved plus 600 S.F. Addition (Excludes Pond Areal
Feature
Area Acres
Area (Square Feet
Percent Area
Total Land
0.737
32,124.00
100.0
Building
0.174
7,600.00
23.7
Drives & Parking
0.317
13,813.00
43.0
Sidewalks
0.030
1,317.00
4.1
Landscaping
0.215
1 9,380.00
29.2
TARTY,, 3 - Lot 3 — On -Site Detention
Existing Volume
Acre -Feet
Existing Release (cfs)
Required Volume
Acre -Feet
Average Release
cfs
0.45
0.68
1 0.44
0.55
Note: Freeboard provided by existing On -Site parking area in event of plugged outlet.
Based on comparative analysis of the tabulated data above, there is roughly a 1.4 percent increase
in the weighted CCf factor, which includes area within the existing detention pond located in the
southeast area of the Site. This translates into what might be considered a negligible increase in
impervious On -Site area.
Using City of Ft. Collins' 1997 rainfall data in conjunction with a total 7,600 square foot area that
could be occupied by a fully built out building envelope, a total detention volume of 0.44 acre-
feet is required. Note, this volume estimate accounts for an average release rate of 0.55 cfs (less
than the approved/existing release rate) rather than historic allowable discharge at 0.69 cfs.
Considering that the existing pond has a volume of 0.45 acre-feet, the proposed addition (which
assumes a fully built out Site) would still require less detention volume than what's already
provided. Further, in the event of plugging at the pond's outlet, there is capacity within On -Site
parking, and it is unlikely that any potential ponding that would result in such an event would
adversely impact vehicles or adjacent properties.
Therefore, where the proposed addition would be well the limits of the previously approved fully
developed Site plan, and given that the proposed addition up to 600 square feet would add a
negligible increase to impervious area, and that the existing pond has adequate storage capacity, it
is recommended that the City grant approval to the said addition, and not require any further
improvements to On -Site detention or receiving stormwater facilities associated with the Project.
We appreciate your consideration to this analysis, and look forward to your approval of the
respective Site plan as proposed here. Should you have any question related to the analysis,,
please feel free to call me at (970) 482-5922.
Respectfully, O�
827
Stanley E. Dunn,
Project Engineer
cc: 1012-001 file
PROJECT SCHEMATIC
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PREVIOUS ANALYSIS
A E., r;2,r8c
PR{:J•7ECT: CENTRE IOTH FILING
JOB NUMBER- 035--064
DESIGN ENGINEER- SAM
BASIN DESIGNATION -A
DE-TEF'M I NE E Y. I ST I NG O FOR:- 2 YEAR' STORH
HIS7C:iRIC RUPdOFF COEFFICIENT .2
BASIN SLOPE: .6 PERCENT'
BASTid LENIOTH :=50 FEET
A RE A 2.3, 7:-
ACRES
HIST TC
))*SORROOT 250
1' -31
HI'STOP,IC RAINFALL IN-VENSITY:
HISTORIC OUTFALL: .683.7153
>>/ .6
31.54494 MINUTES
1 . 4::911 o 1 INCHES /HOUR
CUBIC FEET' PER SECOND
DE T'E:RM I I'4AT I ON OF DEl-ENT' I ON PONI) VOLUME FOR DEVELOPED CONDITIONS
DEVELOPED ST'Of?M:
100
YEAR STORM
DEVELOPED RUNOFF COEFFICIENT
.69
CCI-AC = .69 - .
1.25
-:
2. 048438
DCIRATION
GROSS VOL.
OUTFLOW VOL.
DETENTION VOL.
MIN
CU. FT. -,
CU. f".T.
CU. FT
5
5604.525
205.i146
5399.41
10
8628.019
410.2292
8217.79
15
10987.82
615.3439
10372.48
:10
1 5 191 . 2.1
123(). 6S8
13960. C3
45
18251.58
1646.032
16405.55
6
19247.. 12
. 2461 . 375
16785. 74
9il
20795.74
3692.063
17103.67
120
2 1232. 2
4922. 751
163 15. 45
ISO i
23008. 05
7334. 1.26
15623. 92
25662.83
14768.25
10894.57
F: C:U I RF_D DETENTION
VOLUME IS
17103.67
CU. FT. OR
3926463
ACRE FEET
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PROPOSED ADDITION ANALYSIS
SEAR•BROWN
�CLIENT:�Project No: lolz-.el
Project: C/-7---Ac� 'C>,-A Checked By:
By: Date_ Sheet: Of:
CLIENT: Ccce-,Aj,6& Aes.ya,rt:o - Project No: iaiz-edi
SEAR•BROWN
Project: Checked By:
By: � Date: « Z617Sheet:
Of:
------------------------------------------------------------------------------
------------------------------------------------------------------------------
DETENTION POND SIZING BY FAA METHOD
Developed by
Civil Eng. Dept., U. of Colorado
Supported by Denver Metro Cities/Counties Pool Fund Study
Denver Urban Drainage and Flood Control District, Colorado
------------------------------------------------------------------------------
------------------------------------------------------------------------------
USER=Kevin Gingery...........................................................
EXECUTED ON 10-27-2002 AT TIME 15:45:07
PROJECT TITLE: CENTRE FMILY DENTISTRY (CAT LOTH) PROP. ADDITION
**** DRAINAGE BASIN DESCRIPTION
BASIN ID NUMBER = 1.00
BASIN AREA (acre)= 2.38
RUNOFF COEF = 0.70
***** DESIGN RAINFALL STATISTICS
DESIGN RETURN PERIOD (YEARS) = 100.00
INTENSITY(IN/HR)-DURATION(MIN) TABLE IS GIVEN
DURATION 5 10 20 30 40 50 60 80 100 120 150 180
INTENSITY 9.9 7.7 5.6 4.5 3.7 3.2 2.9 2.2 2.0 1.9 1.5 1.3
%zec.P
***** POND OUTFLOW CHARACTERISTICS:
MAXIMUM ALLOWABLE RELEASE RATE _ .6837153 CFS s APPnaVGD �144f ,
OUTFLOW ADJUSTMENT FACTOR = .8'
AVERAGE RELEASE RATE _ .5469722 CFS� ��� 1ZcdaJl(,G�u2
AVERAGE RELEASE RATE = MAXIMUM RELEASE RATE * ADJUSTMENT FACTOR.
***** COMPUTATION OF POND SIZE
-----------------------------------------------------
RAINFALL
RAINFALL
INFLOW
OUTFLOW
REQUIRED
DURATION
INTENSITY
VOLUME
VOLUME
STORAGE
MINUTE
INCH/HR
ACRE -FT
ACRE -FT
ACRE -FT
-----------------------------------------------------
0.00
0.00
0.00
0.00
0.00
5.00
9.95
0.11
0.00
0.11
10.00
7.72
0.18
0.01
0.17
15.00
6.66
0.23
0.01
0.22
20.00
5.60
0.26
0.02
0.24
25.00
5.06
0.29
0.02
0.27
30.00
4.52
0.31
0.02
0.29
35.00
4.13
0.33
0.03
0.31
40.00
3.74
0.35
0.03
0.32
45.00
3.49
0.36
0.03
0.33
50.00
3.23
0.37
0.04
0.34
55.00
3.05
0.39
0.04
0.35
60.00
2.86
0.40
0.05
0.35
65.00
2.69
0.40
0.05
0.36
70.00
2.53
0.41
0.05
0.36
75.00
2.37
0.41
0.06
0.35
80.00
2.20
0.41
0.06
0.35
85.00
2.15
0.42
0.06
0.36
90.00
2.10
0.44
0.07
0.37
95.00
2.05
0.45
0.07
0.38
100.00
2.00
0.46
0.08
0.39
105.00
1.98
0.48
0.08
0.40
110.00
1.95
0.50
0.08
0.41
115.00
1.92
0.51
0.09
0.42
120.00
1.90
0.53
0.09
0.44
125.00
1.84
0.53
0.09
0.44
130.00
1.78
0.54
0.10
0.44
135.00
1.72
0.54
0.10
0.44
140.00
1.67
0.54
0.11
0.43
145.00
1.61
0.54
0.11
0.43
150.00
1.55
0.54
0.11
0.42
155.00
1.50
0.54
0.12
0.42
`� &&-Ss ridAk4 QK'5ri.-JG
7 PoNA vot-V r"t
-----------------------------------------------------
THE REQUIRED POND SIZE = .4373818 ACRE -FT
THE RAINFALL DURATION FOR THE ABOVE POND STORAGE= 125 MINUTES
***** GEOMETRIES OF AN EQUIVALENT CIRCULAR POND
-----------------------------------------------------
STAGE
CONTOUR
CONTOUR
POND
POND
(DEPTH)
DIAMETER
AREA
SIDE SLP
STORAGE
FEET
FEET
ACRE
FT/FT
ACRE -FT
----------------------------------------'-------------
0.00
0.00
0.00
10.00
0.00
0.50
10.00
0.00
10.00.
0.00
1.00
20.00
0.01
10.00
0.00
1.50
30.00
0.02
10.00
0.01
2.00
40.00
0.03
10.00
0.02
2.50
50.00
0.05
10.00
0.04
3.00
60.00
0.06
10.00
0.07
3.50
70.00
0.09
10.00
0.10
4.00
80.00
0.12
10.00
0.16
4.50
90.00
0.15
10.00
0.22
5.00
100.00
0.18
10.00
0.30
5.50
110.00
0.22
10.00
0.40
6.00
120.00
0.26
10.00
0.52
6.50
130.00
0.30
10.00
0.66
-----------------------------------------------------
❑0.00
0.52
6.50
130.00
0.30
10.00
0.66
SEAR -BROWN
Letter Of Transmittal
209 SOUTH MELDRUM
FORT COLLINS, COLORADO 80521-2603
(970)482-5922 Fax: (970) 482-6368
DATE
)�� s6 rt, ,P/ROJ. NO./a/2-eo/
R`,_
ATTN �� ✓ ,C:iL.�crc�
WE ARE SENDING YOU [Attached ❑ Under Separate Cover ❑
❑ Prints ❑ Reproducibles ❑ Specifications ❑
❑ Copy of Letter ❑ Change Order ❑
Transmitted Via
Shop Drawings
COPIES
DRAWING
DATE
DESCRIPTION
oitT
TRANSMITTED
❑ For Approval ❑ As Requested E4r or Your Use ❑ For Review and Comment
COMMENTS
PP f 2N /��'� • L' QvGS 7®N r
COPY TO with (❑) Enc.
with (❑) Enc.
L L
SIGNED
#SB-01-FC (06/00)
SEAR• BROWN
209 SOUTH MELDRUM
FORT COLLINS, COLORADO 80521-2603
(970)482-5922 Fax: (970) 482-6368
TOr*/ off'C O wi rS
�100 LA)oevi--, car
_X;z: S Co
ATTNSut=-
WE ARE SENDING YOU
❑ Prints
❑ Copy of Letter
Eg-'�A-ttached ❑
❑ Reproducibles ❑
❑ Change Order ❑
DATE PROJ.NO.
RE is a-r✓i7Si --�i4%/01-9
Under Separate Cover ❑
Specifications ❑
Transmitted Via
Shop Drawings
COPIES
DRAWING
DATE
DESCRIPTION
2
-
.� ��
ax✓,.�-ram �.2.4.,..�-
TRANSMITTED �
❑ � For Approval ❑ As Requested ❑ For Your Use ror Review and Comment
COMMENTS
G Z T
COPY TO
with (❑) Enc.
with (❑) Enc. SIGNED
#SB-01-FC (06/00)
SEAR BROWN
PO
October 27, 2002
Mr. Glen D. Schlueter
City of Ft. Collins
700 Wood Street
Ft. Collins, CO 80522
C @[9u
HITE IS 209 South Meldrum
nINE
G I 1.ins,
2 phone
rau 97
RE: PRELEMNARY ABBREVIATED DRAINAGE REPORT FOR THE CENTRE
FAMILY DENTISTRY — CENTRE FOR ADVANCE TECHNOLOGY, 10 FILING
Dear Glen:
This abbreviated drainage report is provided in response to Lockwood Architect's request for
drainage analysis associated with the proposed addition of the Centre Family Dentistry office at
the existing Centre For Advanced Technology 10'' Filing (CAT). Specifically, the proposed
addition will be located at CAT 10th Filing, in the South half of Section 23, Township 7 North,
Range 69 West of the 60' P.M., in the City of Ft. Collins, Larimer County, Colorado. More
generally, the Project would be an addition off an existing structure located just south of Centre
Avenue and west of Worthington Circle.
The approved and recorded Site Plan (SBG, 1990) shows a 7,000 square foot building envelope.
However, the existing structure is approximately 4,000 square feet. Currently, there exists a
detention pond facility in the southeast area of the subject property designed to accommodate the
previously planned and approved building envelope of 7,000 square feet as well as ancillary
parking.
The proposed addition is up to 600 square feet, and would extend beyond the existing building
envelope, possibly displacing up to three parking stalls. Sidewalk connections would be
maintained to the greatest extent possible. Under current developed site conditions the proposed
addition would occupy up to approximately 4,600 square feet. In the event that the Owner
proceeded with the originally planned and approved envelope area plus the 600 square foot
addition, the total area would sum to about 7,600 square feet. The analysis presented herein
considers the most conservative case of a fully built 7,600 square foot building structure.
To remain consistent with past Site analysis and City stormwater guidelines, the analysis
contained here uses Rationale Method factors associated with weighted runoff coefficients
("CCf"), current City rainfall data as applied to entire Site, and the FAA Detention Pond Method.
Beyond the proposed addition and ancillary minor improvements (i.e. landscaping, parking
reconfigurations, etc.) the Site will essentially remain the same. Drainage will flow south through
the Project to an existing detention pond, where it will be attenuated and released at the originally
approved rate of 0.68 cfs to the Centre Avenue storm drainage system which conforms to the
Drainage Report for the Centre for Advanced Technology Special Improvements District,
February 1987, RBD, Inc. Engineering Consultants.
For informational purposes, Site details for the originally approved Lot 3 layout and proposed
conditions are tabulated below showing the relative changes that are used for drainage analysis of
the proposed addition.
TABLE 1 - Lot 3 — As OriEinally ADDroved (Excludes Pond Areal
Feature
Area Acres
Area (Square Feet
Percent Area
Total Land
0.737
32,124.00
100.0
Building
0.149
7,000.00
21.8
Drives & Parking
0.321
13,999.75
43.6
Sidewalks
0.034
1,483.00
4.6
Landsca2ing 1
0.233 1
9,641.25
30.0
TABLE 2 - Lot 3 — As Ori0nally ADaroved alus 600 S.F. Addition (Excludes Pond Areal
Feature
Area Acres
Area (Square Feet
Percent Area
Total Land
0.737
32,124.00
100.0
Building
0.174
7,600.00
23.7
Drives & Parking
0.317
13,813.00
43.0
Sidewalks
0.030
1,317.00
4.1
Landsca2ing
1 0.215
1 9,380.00
1 29.2
TABLE 3 - Lot 3 — On -Site Detention
Existing Volume
Acre -Feet
Existing Release (cfs)
Required Volume
Acre Feet
Average Release
cfs
0.45
0.68
0.44
0.55
Note: Freeboard provided by existing On -Site parking area in event of plugged outlet.
Based on comparative analysis of the tabulated data above, there is roughly a 1.4 percent increase
in the weighted CCf factor, which includes area within the existing detention pond located in the
southeast area of the Site. This translates into what might be considered a negligible increase in
impervious On -Site area.
Using City of Ft. Collins' 1997 rainfall data in conjunction with a total 7,600 square foot area that
could be occupied by a fully built out building envelope, a total detention volume of 0.44 acre-
feet is required. Note, this volume estimate accounts for an average release rate of 0.55 cfs (less
than the approved/existing release rate) rather than historic allowable discharge at 0.69 cfs.
Considering that the existing pond has a volume of 0.45 acre-feet, the proposed addition (which
assumes a fully built out Site) would still require less detention volume than what's already
provided. Further, in the event of plugging at the pond's outlet, there is capacity within On -Site
parking, and it is unlikely that any potential ponding that would result in such an event would
adversely impact vehicles or adjacent properties.
Therefore, where the proposed addition would be well the limits of the previously approved fully
developed Site plan, and given that the proposed addition up to 600 square feet would add a
negligible increase to impervious area, and that the existing pond has adequate storage capacity, it
is recommended that the City grant approval to the said addition, and not require any further
improvements to On -Site detention or receiving stormwater facilities associated with the Project.
We appreciate your consideration to this analysis, and look forward to your approval of the
respective Site plan as proposed here. Should you have any question related to the analysis,
please feel free to call me at (970) 482-5922.
Respectfully,
Stanley E. Dunn, P.E.
Project Engineer
cc: 1012-001
PROJECT SCHEMATIC
Ex. Public
Improvements
I Ex. Sidewalk
+0100 f;-
({Zoo7�-
PREVIOUS ANALYSIS
A"T f.
PRo.-f Ec,r CEHI RE
*308 NUMBER -
DESIGN ENGINEER:
D,_)TH FILING
SAM
DESIGNATION =t E, I -A
DETERMINE EXISTING Q. FOR
YEAR S FORM
Z=m
HISTORIC RliNlOFF COEFFICIENT .2
BA�;.ql;'4 'ZiLOPE- .6 PERCENT
BASJOI LENGTH 250 FEET
A RE
HISI TC
*SQRR00T 2=0
HISTORIC RAINFALL INTENSITY:
HISTORIC OUTFALL- .6837153
.2
.6
31.54494 MINUTES
1. 439401 INCHES/HOUR
CUBIC FEET PER SECOND
DETG.RMIP,IATION OF DETENTION POND VOLUME FOR DEVELOPED CONDITIONS
DEVE'LOFIED
STOF'M,.
100
Y E A R. STO R t I
DEVE[ OFT:-D
RUNOFF COEFFICIENT
.69
CCF'MC
.6?
1.25
2. 0.48438
DUF"'ATION
GROSS VOL.
OUTFLOW VOL.
DETENTION VOL.
M I N
CU. FT.
CU. FT.
CU. FT
5604.525
205.1146
5399.41
I' y
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410.2292
8217.79
15
10997.82
615.3439
10372.4e
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18 2'1 . 58
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REiDUIRED DETENTION
VOLUME IS
17103.67
CU. FT. OR
.7.926463
ACRE FEET
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PROPOSED ADDITION ANALYSIS
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SEAR• BROWN
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CLIENT: /,w.. Ae-c,,,4,mc-,.s Project No:
Project: CM-- Checked By:
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4CLIENT: Loci �.,,U, ��„a, ��,-� Project No: l o li- �dl
Project: fZA,-<�-,Checked By:
may: Date: « Lc o Sheet: Of:
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8L)1.`� o/rr- r-0 �60v s.�
DETENTION POND SIZING BY FAA METHOD
Developed by
Civil Eng. Dept., U. of Colorado
Supported by Denver Metro Cities/Counties Pool Fund Study
.Denver Urban Drainage and Flood Control District, Colorado
-------------------------------
USER=Kevin Gingery...........................................................
EXECUTED ON 10-27-2002 AT TIME 15:45:07
PROJECT TITLE: CENTRE FMILY DENTISTRY (CAT LOTH) PROP. ADDITION
**** DRAINAGE BASIN DESCRIPTION
BASIN ID NUMBER = 1.00
BASIN AREA (acre)= 2.38
RUNOFF COEF = 0.70
***** DESIGN RAINFALL STATISTICS
DESIGN RETURN PERIOD (YEARS) = 100.00
INTENSITY(IN/HR)-DURATION(MIN) TABLE IS GIVEN
DURATION 5 10 20 30 40 50 60 80 100 120 150 180
INTENSITY 9.9 7.7 5.6 4.5 3.7 3.2 2.9 2.2 2.0 1.9 1.5 1.3 <-- /?,F-?
%ze2iP
***** POND OUTFLOW CHARACTERISTICS:
MAXIMUM ALLOWABLE RELEASE RATE _ .6837153 CFS - QAPPadVdb (194F.)
OUTFLOW ADJUSTMENT FACTOR = .8 ' Agc/1 .wrw1 >'ttmu!.c
AVERAGE RELEASE RATE _ .5469722 CFS._-- R'crL Ztra�-'JK, sA-G-1c2
AVERAGE RELEASE RATE = MAXIMUM RELEASE RATE * ADJUSTMENT FACTOR.
***** COMPUTATION OF POND SIZE
-----------------------------------------------------
RAINFALL
RAINFALL
INFLOW
OUTFLOW
REQUIRED
DURATION
INTENSITY
VOLUME
VOLUME
STORAGE
MINUTE
INCH/HR
ACRE -FT
ACRE -FT
ACRE -FT
-----------------------------------------------------
0.00
0.00
0.00
0.00
0.00
5.00
9.95
0.11
0.00
0.11
10.00
7.72
0.18
0.01
0.17
15.00
6.66
0.23
0.01
0.22
20.00
5.60
0.26
0.02
0.24
25.00
5.06
0.29
0.02
0.27
30.00
4.52
0.31
0.02
0.29
35.00
4.13
0.33
0.03
0.31
40.00
3.74
0.35
0.03
0.32
45.00
3.49
0.36
0.03
0.33
50.00
3.23
0.37
0.04
0.34
55.00
3.05
0.39
0.04
0.35
60.00
2.86
0.40
0.05
0.35
65.00
2.69
0.40
0.05
0.36
70.00
2.53
0.41
0.05
0.36
75.00
2.37
0.41
0.06
0.35
80.00
2.20
0.41
0.06
0.35
85.00
2.15
0.42
0.06
0.36
90.00
2.10
0.44
0.07
0.37
95.00
2.05
0.45
0.07
0.38
100.00.
2.00
0.46
0.06
0.39
105.00
1.98
0.48
0.08
0.40
110.00
1.95
0.50
0.08
0.41
115.00
1.92
0.51
0.09
0.42
120.00
1.90
0.53
0.09
0.44
125.00
1.84
0.53
0.09
0.44
130.00
1.78
0.54
0.10
0.44 �-
135.00
1.72
0.54
0.10
0.44
140.00
1.67
0.54
0.11
0.43
145.00
1.61
0.54
0.11
0.43
150.00
1.55
0.54
0.11
0.42
155.00
1.50
0.54
0.12
0.42
L.t'SS TigPh( C'KiSriNG <
77 7'o w � J o t�V rn t rj
-----------------------------------------------------
THE REQUIRED POND SIZE _ .4373818 ACRE -FT
THE RAINFALL DURATION FOR THE ABOVE POND STORAGE= 125 MINUTES
***** GEOMETRIES OF AN EQUIVALENT CIRCULAR POND
-----------------------------------------------------
STAGE
CONTOUR
CONTOUR
POND
POND
(DEPTH)
DIAMETER
AREA
SIDE SLP
STORAGE
FEET
-----------------------------------------------------
FEET
ACRE
FT/FT
ACRE -FT
0.00
0.00
0.00
10.00
0.00
0.50
10.00
0.00
10.00
0.00
1.00
20.00
0.01
10.00
0.00
1.50
30.00
0.02
10.00
0.01
2.00
40.00
0.03
10.00
0.02
2.50
50.00
0.05
10.00
0.04
3.00
60.00
0.06
10.00
0.07
3.50
70.00
0.09
10.00
0.10
4.00
80.00
0.12
10.00
0.16
4.50
90.00
0.15
10.00
0.22
5.00
100.00
0.18
10.00
0.30
5.50
110.00
0.22
10.00
0.40
6.00
120.00
0.26
10.00
0.52
6.50
130.00
0.30
10.00
0.66
-----------------------------------------------------
❑0.00
0.52
6.50
130.00
0.30
10.00
0.66