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JTORM DRAINAGE REPORT
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0 For
I College Station Fire Station #3
Barron Road
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College Station, Texas .
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Contract No.
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0 Date: _1 February 2006
—
I
I Drainage Basin: Lick Creek, Brazos County
I Architect: BRW Architects, Inc., College Station,TX
I Engineer: Larry 0. Degelman, P.E., College Station,TX
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STORM DRAINAGE REPORT
1 For
1 _ College Station Fire Station #3
1
Barron Road
► College Station, Texas
1
1
1
1 Contract No.
Date: 1 February 2006
1
1 Drainage Basin: Lick Creek, Brazos County
Architect: BRW Architects,Inc., College Station,TX
1
1 Engineer: Larry O. Degelman,P.E., College Station, TX
1
1
1
1 "I hereby certify that this report for the drainage design of the College Station Fire
Station#3 site in College Station, Texas was prepared by me in accordance with the
provisions of the City of College Station Drainage Design Criteria Manual for the owners
1 thereof."
1LairAte, 7 1 February 2006
F‘
1 *fP.''"` T•~-1 `�°f�4 Larry 0. Degelman,P.E.
1.* is Registered Professional Engineer
► j....`LARRY 0. DEGELMANState of Texas No. 43197
.
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►
TABLE OF CONTENTS
► Subject Page
►
I. Objective 1
► IL Scope 1
►
►
HL Procedure 1
► IV. General Location 1
► V. Property Description 1
VI. Site Drainage Characteristics 1
VII. Hydrologic Criteria 3
VIII. Design Calculations 3
IX. Triangular Hydrographs 5
X. Detention Pond Design 7
XI. Orifice Design 7
Objective:
1 The objective of this analysis is to assure that the post-development runoff discharge rate
1 from the project site does not exceed that of the pre-development discharge rate for 10-
1 year, 25-year, 50-year, and 100-year storm events.
H. Scope:
This analysis only includes runoff calculations for the subject property site. Calculations
do not include any of the adjacent properties or any upslope sites that may contribute
runoff to this property.
III. Procedure:
The procedures followed in this analysis were to: (1)utilize Section III of the City of
College Station Drainage Criteria Manual to obtain runoff coefficients for specified storm
1 event return periods for the site's soil condition, (2)develop pre- and post-development
1 runoff flow intensities using the Rational Method and Graphical Hydrographs, and (3)
configure detention ponds and the outflow orifice(s)to assure that discharge rates do not
exceed the pre-development condition.
IV. General Location:
a. Property is located on Barron Road, about one block from the intersection with
Alexandria Avenue, and south of Graham Road in College Station, Texas.
'
b. A drainage easement exists on the project's Northwest side that discharges in an
1 northeasterly direction toward Alexandria Avenue on a less than 1% slope.
1 c. Because of the almost level condition at the rear of the site, either a continuous linear
basin or multiple small detention basins are proposed, all of which would have a drain
outlet toward the northwest easement. (See Figure 1.)
1
V. Property Description:
a. Acreage= 2.2 acres. About 315 ft. by 305 ft.
b. Undeveloped natural grassland area with a 3.6%down slope to the northwest side.
1 c. Maximum runoff sheet flow distance is 305 feet.
1 d. Owner: City of College Station.
e. Development additions: Fire station, parking lot, driveway with turning area. Total
developed area(paved and roof)= 0.69 acres.
f. New unpaved areas will be 1.51 acres of grass area.
VI. Site Drainage Characteristics:
a. The site is a 2.2-acre lot containing natural grassland areas with an average downward
1
slope of 3.6%toward the northwest side. Outflow travels northeasterly along a
) drainage easement on the northwest property line with negligible slope (< 1%.)
1 b. In the post-development scenario, approximately 30,000 sq.ft. (or 0.69 acres) will be
covered by the fire station and paved parking areas (see Figure 1.) Neither the
building nor any parts of the parking area are in the calculated detention pond area.
The elevation of the building slab is ten (10)feet above the calculated top level of the
) detention pond. The lowest corner of the parking lot is 1 ft. above the 100-yr event
water detention level.
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1 Fig. 1 Post-Development Site Plan
1
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1 2
1
VH. Hydrologic Criteria:
a. Design rainfall: Using the College Station intensity-duration-frequency curve
coefficients from Figure III-1 in the College Station Drainage Criteria Manual, the
average rainfall intensity equation was used,
i =a/(t+b) ^c (1)
where, "i" =rainfall intensity in inches per hour and"t" =the storm duration.
The a, b, and c coefficients for this equation are taken from Figure III-1 and are
shown below under Section VIII, Design Calculations.
b. The surface flow/time equation was used from Fig. 404 of the City of Bryan Drainage
Design Guideline Manual, based on the Hydraulic Manual issued by the Texas Dept.
of Highways and Public Transportation(1985). Time of Concentration:
T= 1.8 * (1.1 —C) / SA0.2 (2)
where, T=time in minutes; C=Runoff Coefficient;D=Distance to maximum
point on site, in feet; and S =average slope of site, in percent.
c. Pre- and post-development runoff discharge calculation method:
Rational Method,Q—C*I*A .(3)
d. Detention storage and discharge method: Triangular Hydrographic Method.
VIM Design Calculations:
Hydrologic Calculations for detention ponds:
Rational Method: Q=CIA, where C^weighted runoff coefficient(sourced from Table III-
1 1 of the College Station Drainage Criteria Manual); I=average rainfall intensity(inJhr.); and
1 A=Tributary Area(acres). For the subject site, A=2.2 acres, Average Slope= 3.6%,
Maximum distance=305 feet.
Rainfall Intensity: I=a/(t+b)A c,
Where,
I=rainfall, in inches per hour,
t= storm duration time, in minutes, and
a, b, c coefficients are from Table 1.
Table 1. Intensity-duration-frequency curve coefficients
Storm frequency a b c
10-yr 80 8.5 0.763
25-yr 89 8.5 0.754
50-yr 98 8.5 0.745
100-yr * 104.5 8.5 0.726
Source: Figure III-1 College Station Drainage Criteria Manual.
* The 100-yr equation is derived from curve in Fig. III-1.
Pre-development:
Calculation results for both the pre- and post-development are shown in Tables 2
and 3. None of the post-development calculations include improvements to the
properties outside the project boundaries.
3
5
0
0 Table 2. Pre-Development Runoff
Runoff Coefficient from College Station Manual and Resulting Runoff, Q
0 Parcel Area(ac.) Storm event criterion
10-year 25-year - 50-year 100-year
Natural grasslands 2.2 0.35 0.39 0.42 0.45
Time of Concentration (min.) 18.1 17.1 16.4 15.7
Equiv. Manning flow"n" 0.48 0.45 0.44 0.42
Rainfall Intensity (in./hr.) 6.54 7.72 8.93 10.35
Peak Runoff Rate(cu.ft./sec.) 5.04 6.62 8.25 10.25
1 Total Pre-Dev Discharge,Qp _
1
1
0 Table Post-Development Post-Develo e t
Runoff
P n
/ Runoff Coefficient Calculations (weighted average method)and Resulting Runoff, Q
1 Parcel Area (ac.) Storm event criterion
2.2 10-year 25-year 50-year 100-year
Natural grasslands 1.51 0.35 0.39 0.42 0.45
1 Paved/roof area 0.69 0.9 0.9 0.9 0.9
1 Weighted average"C" 0.52 0.55 0.57 0.59
1 Time of Concentration (min.) 14 13.3 12.8 12.3
1 Equiv. Manning flow"n" 0.37 0.35 0.34 0.33
1 Rainfall Intensity (in./hr.) 7.44 8.71 10.04 11.57
1 Peak Runoff Rate(cu.ft/sec.)
/ 8.51 10.54 12.59 15.02
Total Post-Dev Discharge,Qn
1 Total Pre-Dev Discharge, Qp 5.04 6.62 8.25 10.25
1 Added Discharge (cfs) 3.47 3.92 4.34 4.77
1
1 Required detention volumes, 3675 3902 4128 4333
1 cu.ft. (see Hydrographs.)
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M. Triangular Hydrographs:
10 Year Event(College Station,Vol...3675 tuft.)
--4.-Pre -u-Post
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Voknme -3675 cu. ftt.
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0 10 20 30 40 50
1 Time(min.)
1 Fig.2 Hydrograph for 10-year storm event
1
1
25-Year Event(College Station,Vol...3902 cu ft.)
1
1 -4-Pre i--Post
10 - . 4. .
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1 2 999 221
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1 0 10 20 30 40 50 W
Time(min.)
1 Fig. 3 Hydrograph for 25-year storm event
1
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' 60 Year Event(College Station,Vol.=4128 cu ft)
--*--Pre --e-Post
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0r_h 16 4.1082 Volume sr 4128 cu. ft.
to' 12 8,5 44 _--Z-`-',_, -_:,,_:--..r, `
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L .: - 38.4.272
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1 0 0.0 n _ ..- ,--K . 7[14,11 19.2.0
0 10 20 30 40 5b 60
1
Time(min.)
/ Fig. 4 Hydrograph for 50-year storm event
1
1
/ 100 Year Event(College Station,Vol.=4333 cu.ft.)
/ tPre -a-Post
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17a294 --,_ Volume -r 4333 ecu. ft
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1 - . a. . 15 9,333
1 2
1 0 5 10 15 20 25 30 35 4( 4 50
1 Time(min.)
Fig. 5 Hydrograph for 100-year storm event
1
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X. Detention Pond Design:
Objective: Maintain the pre-development outflow rate.
0
From the 100-year Hydrograph,the pre-development and the allowable discharge rate is
10.25 cfs. To maintain the same discharge rate in the post-development phase,the required
detention volume is 4333 cu.ft. as determined from the 100-yr hydrograph. Upon
examination of the site plan(See Figure 1), this volume can be captured in linear detention
ponds totaling 4000 sq.ft. at the north side(lowest portion)of the site by letting water rise to
a 2-ft. depth. The pond would have a trapezoidal cross-section with a one-in-four bottom
slope, netting an average top width of 20 ft. and a lower dimension of 4 ft. (See Figure 6.)
The total surface length of the ponds would be about 200 feet.
P
w �1' 8-ft.
V
8-ft. + 4-ft + 8-ft.
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1 Fig. 6. Typical cross-section through detention ponds
The calculated detention volume is as follows:
Cross-section area,A=((20'+4')/2 * 2')=24 sq.ft.
1 Average Length=(200' + 184')/2= 192 ft.
1 Pond volume, V=A * Average Length=24 * 192' =4608 cu.ft. (meets criteria of 4333
cu.ft.)
XI. Orifice Design:
The discharge rate must be maintained at 10.25 cfs. For an orifice,the flow is defined by:
1 Q=C * A * 2gh (4)
where, C is a flow constant of 0.7, A=the orifice area, g=acceleration of gravity
(32.2 ft/sec2), and h=the height from the top of the water to the orifice centroid.
In order to retain sufficient volume and keep flow rates low enough for the 10-year, 25-year,
50-year, and 100-year storm events, a V-shaped triangular orifice is selected. By integrating
formula No. 4 over the entire height of a triangle,the formula for the discharge is defined by:
Q=C * W * 4/15 * 2g (h)3/2 (5)
1 where,W=the width of the top of the triangular orifice,
h=height from top of water to the lower tip of the triangular orifice.
1 7
1
.460
1
1
Solving for W for the 100-yr storm case, where h =2 ft.
11 W=Q/[C * 4/15 * 4g (h)3/2] = 10.25 / [1.5 * 2.828] =2.42 feet(or 29") (6)
Any number of triangular notches may be used adding up to 29".
0
A sample orifice design is shown in the detention structure in Figure 7.
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� Fig. 7 Detention structure showing triangular outlet orifice
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0 The storm water heights were also computed for 10-year, 25-year, and 50-year storm events.
0 These results are shown in Table 4 and in Figure 8. The resultant discharge rates are determined
from equation 5 and shown in Table 4. All discharge rates are at or below the allowed rates.
0
0 Table 4. Water depths for various storm events.
! Storm frequency Detention Depth of pond Allowed Actual Depth of Pond
Volume (ft.)based on discharge discharge (ft.)based on
(cu.ft.) volume. rate(cfs) rate (cfs) flow rate.
0 10-year 3675 1.47 5.04 5.00 1.47
1 25-year 3902 1.64 6.62 6.60 1.64
_ 50-year 4128 1.79 8.25 8.26 1.79
1 100-year 4333 1.95 10.25 10.25 1.95
1
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1 Et-ft. 4-ft. 8-ft. .i
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1 Fig. 8 Pond cross-section showing depths for various storm events.
1 ******* End of Report *******
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1TORM DRAINAGE REPORT
II
II For
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CAlgge Station Fire Station #3
IP
_____Barron Road
111
College Station, Texas
II
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II Contract No.
IP
0 Date: 1 February 2006
—_
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111 Drainage Basin: Lick Creek, Brazos County
I Architect: BRW Architects, Inc.,College Station,TX
1 Engineer: Larry 0. Degelman, P.E.,College Station,TX
I
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STORM DRAINAGE REPORT
1 For
_ College Station Fire Station #3
Barron Road
College Station, Texas
1 Contract No.
Date: 1 February 2006 _
Drainage Basin: Lick Creek,Brazos County
Architect: BRW Architects,Inc.,College Station,TX
Engineer: Larry O.Degelman,P.E., College Station,TX
1
1
"I hereby certify that this report for the drainage design of the College Station Fire
Station#3 site in College Station, Texas was prepared by me in accordance with the
1 provisions of the City of College Station Drainage Design Criteria Manual for the owners
thereof."
.,12 1 February 2006
1 =��Q�•'' ....'4.gt#y' Larry 0.Degelman,P.E.
* , Registered Professional Engineer
i�• LARRY 0- DEGELMAN State of Texas No. 43197
.A 43197 14
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TABLE OF CONTENTS
Subject Page
I. Objective 1
1 IL Scope 1
1 1
HL Procedure
1 IV. General Location 1
V. Property Description 1
1 VI. Site Drainage Characteristics 1
VII. Hydrologic Criteria 3
VIII. Design Calculations 3
IX. Triangular Hydrographs 5
X. Detention Pond Design 7
XI. Orifice Design 7
1
1
1
1
1
1
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1
Objective:
1 The objective of this analysis is to assure that the post-development runoff discharge rate
1 from the project site does not exceed that of the pre-development discharge rate for 10-
year, 25-year, 50-year, and 100-year storm events.
1 II. Scope:
This analysis only includes runoff calculations for the subject property site. Calculations
do not include any of the adjacent properties or any upslope sites that may contribute
runoff to this property.
IIL Procedure:
The procedures followed in this analysis were to: (1)utilize Section III of the City of
College Station Drainage Criteria Manual to obtain runoff coefficients for specified storm
1
event return periods for the site's soil condition,(2)develop pre-and post-development
1 runoff flow intensities using the Rational Method and Graphical Hydrographs, and (3)
1 configure detention ponds and the outflow orifice(s)to assure that discharge rates do not
exceed the pre-development condition.
1 IV. General Location:
a. Property is located on Barron Road, about one block from the intersection with
Alexandria Avenue, and south of Graham Road in College Station, Texas.
b. A drainage easement exists on the project's Northwest side that discharges in an
1 northeasterly direction toward Alexandria Avenue on a less than 1% slope.
c. Because of the almost level condition at the rear of the site, either a continuous linear
basin or multiple small detention basins are proposed, all of which would have a drain
outlet toward the northwest easement. (See Figure 1.)
1 V. Property Description:
a. Acreage=2.2 acres. About 315 ft. by 305 ft.
b. Undeveloped natural grassland area with a 3.6%down slope to the northwest side.
c. Maximum runoff sheet flow distance is 305 feet.
) d. Owner: City of College Station.
e. Development additions: Fire station, parking lot, driveway with turning area. Total
developed area(paved and roof)=0.69 acres.
f. New unpaved areas will be 1.51 acres of grass area.
VI. Site Drainage Characteristics:
a. The site is a 2.2-acre lot containing natural grassland areas with an average downward
slope of 3.6%toward the northwest side. Outflow travels northeasterly along a
drainage easement on the northwest property line with negligible slope(< 1%.)
b. In the post-development scenario, approximately 30,000 sq.ft. (or 0.69 acres)will be
covered by the fire station and paved parking areas(see Figure 1.) Neither the
building nor any parts of the parking area are in the calculated detention pond area.
The elevation of the building slab is ten (10)feet above the calculated top level of the
detention pond. The lowest corner of the parking lot is 1 ft. above the 100-yr event
water detention level.
1
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) Fig. 1 Post-Development Site Plan
)
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i 2
1
b
1
VII, Hydrologic Criteria:
a. Design rainfall: Using the College Station intensity-duration-frequency curve
coefficients from Figure III-1 in the College Station Drainage Criteria Manual, the
average rainfall intensity equation was used,
i=a/(t+b)^ c (1)
where, "i" =rainfall intensity in inches per hour and"t"=the storm duration.
The a, b, and c coefficients for this equation are taken from Figure 11I-1 and are
shown below under Section VHI, Design Calculations.
b. The surface flow/time equation was used from Fig. 404 of the City of Bryan Drainage
Design Guideline Manual, based on the Hydraulic Manual issued by the Texas Dept.
of Highways and Public Transportation(1985). Time of Concentration:
T= 1.8 * (1.1 —C) * 4 / S^02 (2)
where, T=time in minutes; C =Runoff Coefficient;D=Distance to maximum
point on site, in feet;and S =average slope of site, in percent.
c. Pre- and post-development runoff discharge calculation method:
Rational Method, Q=C*I*A .(3)
d. Detention storage and discharge method: Triangular Hydrographic Method.
VIII, Design Calculations:
Hydrologic Calculations for detention ponds:
Rational Method: Q=CIA,where C=weighted runoff coefficient(sourced from Table HI-
1 1 of the College Station Drainage Criteria Manual); I=average rainfall intensity (in./hr.); and
A=Tributary Area(acres). For the subject site, A=2.2 acres, Average Slope= 3.6%,
Maximum distance=305 feet.
Rainfall Intensity: I=a/(t+b)^c,
Where,
I=rainfall, in inches per hour,
t= storm duration time, in minutes, and
► a, b, c coefficients are from Table 1.
► Table 1. Intensity-duration-frequency curve coefficients
Storm frequency a b c
► 10-yr 80 8.5 0.763
► 25-yr 89 8.5 0.754
50-yr 98 8.5 0.745
100-yr * 104.5 8.5 0.726
Source: Figure HI-1 College Station Drainage Criteria Manual.
* The 100-yr equation is derived from curve in Fig. IH-1.
Pre-development:
Calculation results for both the pre- and post-development are shown in Tables 2
and 3. None of the post-development calculations include improvements to the
properties outside the project boundaries.
3
j
0
0
Table 2. Pre-Development Runoff
1 Runoff Coefficient from College Station Manual and Resulting Runoff,Q
1 Parcel Area(ac.) Storm event criterion
10-year 25-year 50-year 100-year
Natural grasslands 2.2 0.35 0.39 0.42 0.45
1
1 Time of Concentration (min.) 18.1 17.1 16.4 15.7
1 Equiv. Manning flow"n" 0.48 0.45 0.44 0.42
Rainfall Intensity (in./hr.) 6.54 7.72 8.93 10.35
li
1 Peak Runoff Rate(cu.ft./sec.) 5.04 6.62 8.25 10.25
1 Total Pre-Dev Discharge,Qp
1
1
1 Table 3. Post-Development Runoff
1 Runoff Coefficient Calculations (weighted average method) and Resulting Runoff, Q
1 Parcel Area (ac.) Storm event criterion ,
1 2.2 10-year 25-year 50-year 100-year
Natural grasslands 1.51 0.35 0.39 0.42 0.45
1 Paved/roof area 0.69 0.9 0.9 0.9 0.9
1 Weighted average"C" 0.52 0.55 0.57 0.59
-
1 Time of Concentration (min.) 14 - 13.3 12.8 12.3
1 Equiv. Manning flow"n" 0.37 0.35 0.34 0.33
1 Rainfall Intensity (in./hr.) 7.44 8.71 10.04 11.57
1 Peak Runoff Rate(cu.ftJsec.)
8.51 10.54 12.59 15.02
1 Total Post-Dev Discharge,Q.
1 Total Pre-Dev Discharge, Qp 5.04 6.62 8.25 10.25
Added Discharge (cfs) 3.47 3.92 4.34 4.77
1
1 Required detention volumes, 3675 3902 4128 4333
1 cu.ft. (see Hydrographs.)
1
1
1
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1
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1
1
1
1 4
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IX. Triangular Hydrographs:
10-Year Event(College Station,Vol.-3675 cu.ft.)
1
—41,-Pre -s-Post
' y — ,
' i4,i� 1
181,726
VokjmE IN 3675 cu. ftt.
1
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.,. . .. .� _; 171
0 0 D :_..�- 7£4 •- `4.3,0 1
1 0 10 20 3) 40 50 60
) lime(min.)
1 Fig. 2 Hydrograph for 10-year storm event
1
1
1 25-Year Event(College Station,Vol. .3902 cu.ft.)
1 -4- —
Pre -* Post
1 .11
12
ii
1 13 3,10 r! > — --
a
10
1
17 19_II3 - _
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V,
w
1
1 tg
c 13 3.6 15 4-
1
1 2 w ,,a 27i
i
1 0 10 20 30 40 50 60
Time(min.)
1 Fig. 3 Hydrograph for 25-year storm event
1
1 5
1
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1
0
1 60-Year Event(College Station,Vol..=4128 cu.ft.)
/ -4--Pre -m-Post
1 14
-- 12 8,1259
1
1
16 4,10132 Volume am 4120 cu. ft
1
in �„_
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1
G
/ Ie 120,544
1 4
1 `301.2.72
/ 0 10
20 30
4•0 50 60
Time(min.)
1 Fig.4 Hydrograph for 50-year storm event
1
1
100 Year Event(College Station,Vol.■4333 cu.}t)
1 -.--Pre -m-Post
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1
1 6
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X. Detention Pond Design:
0 Objective: Maintain the pre-development outflow rate.
I
From the 100-year Hydrograph,the pre-development and the allowable discharge rate is
10.25 cfs. To maintain the same discharge rate in the post-development phase, the required
detention volume is 4333 cu.ft. as determined from the 100-yr hydrograph. Upon
examination of the site plan (See Figure 1), this volume can be captured in linear detention
ponds totaling 4000 sq.ft. at the north side (lowest portion) of the site by letting water rise to
a 2-ft. depth. The pond would have a trapezoidal cross-section with a one-in-four bottom
0 slope, netting an average top width of 20 ft. and a lower dimension of 4 ft. (See Figure 6.)
The total surface length of the ponds would be about 200 feet.
I
I
ria t. �-
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t / 9-ft 4-ft. 13-n.
! Fig. 6. Typical cross-section through detention ponds
!
The calculated detention volume is as follows:
! Cross-section area, A=((20'+4')/2 * 2')=24 sq.ft.
Average Length= (200' + 184')/2= 192 ft.
Pond volume, V=A * Average Length=24 * 192' =4608 cu.ft. (meets criteria of 4333
cu.ft.)
1
XI. Orifice Design:
The discharge rate must be maintained at 10.25 cfs. For an orifice, the flow is defined by:
Q =C * A * j2gh (4)
where, C is a flow constant of 0.7, A=the orifice area, g=acceleration of gravity
1 (32.2 ft/sect), and h=the height from the top of the water to the orifice centroid.
In order to retain sufficient volume and keep flow rates low enough for the 10-year, 25-year,
50-year, and 100-year storm events, a V-shaped triangular orifice is selected. By integrating
formula No. 4 over the entire height of a triangle, the formula for the discharge is defined by:
1 Q =C * W * 4/15 * 2g (h)3/2 (5)
where, W=the width of the top of the triangular orifice,
1 h=height from top of water to the lower tip of the triangular orifice.
7
1
II
0
I
111 Solving for W for the 100-yr storm case, where h=2 ft.
W =Q/[C * 4/15 * 1r2g (h)3/2] = 10.25 / [1.5 * 2.828] = 2.42 feet(or 29") (6)
Any number of triangular notches may be used adding up to 29".
10
A sample orifice design is shown in the detention structure in Figure 7.
t
b V-Note rA 1
4 �v--
P cii. aft.
160
',
8-ft. 4-ft. 9-ft.
Ps, X
It
0 Fig. 7 Detention structure showing triangular outlet orifice
0-
The storm water heights were also computed for 10-year, 25-year, and 50-year storm events.
0 These results are shown in Table 4 and in Figure 8. The resultant discharge rates are determined
from equation 5 and shown in Table 4. All discharge rates are at or below the allowed rates.
0
r Table 4. Water depths for various storm events.
0 Storm frequency Detention Depth of pond Allowed Actual Depth of Pond
Volume (ft.)based on discharge discharge (ft.)based on
(cu.ft.) volume. rate(cfs) rate (cfs) flow rate.
1
0 10-year 3675 1.47 5.04 5.00 1.47
0 25-year 3902 1.64 6.62 6.60 1.64
50-year 4128 1.79 8.25 8.26 1.79
100-year 4333 1.95 10.25 10.25 1.95
1
1
1 k 100-yr so-w 25-gr !O-yr
1 AIIIIMMIN�
r-io• r-$• r--6.1 ,
1 0-ft, 4-ft. 0-ft,
N.
1
1
1 Fig. 8 Pond cross-section showing depths for various storm events.
1 ******* End of Report *******
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