HomeMy WebLinkAbout12 The Glade Sec 12 05-34 1311 Southwest PkwyApril 7, 2006
TO:
FROM :
CITY OF COLLEGE S TATION
Planning & Development Services
1101 Texas Avenue, P.O . Box 9960
College Station, Texas 77842
Phone 979.764.3570 /Fax 979.764.3496
MEMORANDUM
Kent Laza, P.E ., Texcon, via fax 690.9797
Bridgette George, Development Coordinator
SUBJECT: Engineering Document Comments for The Glade Sect. 12
Staff reviewed the above-mentioned engineering documents as requested. The following
page is a list of staff review comments detailing items that need to be addressed.
Please address the comments and submit the following information for further staff
review and approval of the plans:
__ One ( 1) sets of revised construction documents.
If you have any questions or need additional information, please call Josh Norton at
979 .764.3570 .
Attachments : Staff review comments
pc: Case File No . DP05-23
ENGINEERING
1. The request to remove the 2 curb inlets on North Bardell Ct, and replace them
with grate inlets has been denied, due to the fact that grate inlets in streets are
not desired and are normally used to serve as area inlets in such applications as
parking lots.
Reviewed by: Josh Norton Date: April 6, 2006
TEX CON
Gen eral Co ntra ctors
D iv. of CDS Ente rprises, Inc .
1707 Graham Rd . • College Station , TX 77845 • 97 9-690-7711 • Fax: 979-690-97 97
March 30, 2006
A lan Gibb s, P .E .
D evelopm ent E ng in eer
C ity of C oll ege Station
P.O . Box 9960
Co ll ege Stati on , TX 778 4 2
RE : R ed es ign of inl et s on N orth B ard ell C ourt
The Gl ad e Subd iv ision , S ection 12 , C o ll ege Station , T exas
D ear A lan :
The h om ebuild er in The G lad e Subdivision co nt act ed u s regarding th e p oss ibility
o f r ed es igning th e curb inlets on N orth B ard e ll C ourt to make them into grate inl et s. T he
reason for d oin g thi s is to ac commod ate dri ve ways into th e homes that mu st b e located
wh ere these curb inl et s wer e ori gin a ll y install ed . The att ach ed plan sho ws our pro p osal
for rebuilding th ese tw o inl et s. On th e attach ed p age I have pro v id ed a br ief d ra in age
rep ort showing th e calculation s fo r th e inl ets we use d t o d es ign th em . We as k ed th at yo u
r eview th e pl ans and th e calcul ati o n s, an d pro v id e an y input yo u h ave r egarding thi s
red esign . Thank yo u .
S in cere ly Y ours ,
/~L ~ Ke nt Laz a , P .E .
P rojec t Manager
attachm ent
The Glade Subdivision, Section 12
Drainage Report
Addendum #1
Q captu red (from original drainage report -Inlet Length Calc ul ations for 100-yr event)
Inlet 1 -Q captured = 5.52 cfs
Inl et 2 -Q captured = 6 .82 cfs
Orifice E qu ation
Q = 4.82 A grate (y)y,
Where Q = flow into the grate ( cfs)
A grate = open area of the grate (ft2
)
y =depth of water o ver the grate (ft)
For Q = 6 .82 cfs
--~'";"-C logging
in (ft ) i (in ) Factor
3 2 .83 408 25 %
4
5
2.45 353 25 %
--·•······································•···--·········-·················"'····················
2.19 3 16 25 %
Req.
Area .... :z ·
(in)
509
From East Jordan Iron Works Catalog
Selected Grate = V-4230 (Heavy Duty) Opening Area = 23 5 in2
2 Grates = 470 in 2
Funct io n a l Op en Area with 25% c lo gging
A orate = 470 / 1.25 = 376 in 2
0
D epth over Grate
2 Y = (Q/(4.82 X A grate ))
y = 0 .29 ft = 3 .5 in fo r Inl e t 2
y =0.19ft =2.3in fo rlnl e tl
The Glade Subdivis i o n
In let Length Calculations
Revised 712005
Inlets On Grade 10 yea r storm
Flow from Y10 Oper 1oo1 Oc...,1e1~ a byp•• <lc ~ured In let# Length
1 -
2
10'
l O'
Area# (ft) I (In)
202 0.303 + 3.64 ----201 0.348 4.17
Transve rse !Crown) slope (ft/ft)
for 27' street = 0 .033
(ft) (els) (els)
0.60 5.97 -1 .66
0.64 6.4 1 -0 .50
Straight Crown Flow (Solved to fi n d actual depth of f low, yl:
a= o.ss • (zin) • s 111 • y"' ¢ y = {0 / [0.56 • (zin) • s"1n"'
n =Roughness Coefficient~ 0 .018
S = Street/Gutter Slope (ft/ft)
y = Depth o! flow at inlet (ft)
Capac ity of Inlets on grade:
Oc = 0 .7' (1/(H, • H2)] • [H,511 -H2
512]
Oc = Flow capacity of inl et (els)
H, =a + y
H2 = a = gutter depression (2" Standard; 4" Recessed)
y = Depth of flow in approac h gutter (ft)
(els)
4.09
5.9 1
O c:wryOYer 0 1ryp.tot• O cmpt.totl 0 10-Tot• Y1 00
(els) l from lnl•t # (els) (els) Ccls) (ft) I (In)
I 0 .00 4 .09 4 .09 0 .339 I 4.07
I 0 .00 5 .9 1 5 .91 o .389 I 4.67
z = Reciprocal oC crown slope
for 27' street = 30
In lets in s u m ps, Wei r Flow :
L = QI (3 ' y"') ¢ y = (QI 3L )213
L = Length of inle t opening (ft)
Q =Flow at inl et (els)
y = total depth of flow on inlet (ft)
ma x y for inlet in sump = 7" = 0 .583'
100 year storm
O per1oot O cmpmclty a .,. •• flc~tured Oc..,ry 0¥., a byp-totll
(ft) (els) (els) (els) (els) ! from Inle t# (els)
0 .63 6 .32 -0 .60 5.52 I 0 .00
~-
0 .68 6 .82 1.14 6.82 l 1.14 -
O upt-totl 0 100.rou11
(els) (els)
5.52 5.52 ----6.82
0 ...., m
::i m co
CD
::0
CD
-0
0
;::i
7.96
m x
()
CD ...., -s.
~
0
3
-i ::::r
CD
G)
m o._
CD
(f)
c
0-o._
~:
Cf)
0
_::i
(f)
CD
Q.
6'
::i
f\.)
m >< ~ -· C"' -)>
s . L .:1u:t1
(ft/ft) (ft)
0 .0 1 10 10 -----0.0110 10
CITY OF COLLEGE STATION
Pla nning & Dn>t!JJpment &rvius
SITE LEGAL DESCRIPTION:
The Glade, Section 12 ,
Lot Tract A ,
Acres 2.553
DEVELOPMENT PERMIT
PERMIT NO . 05-34
FOR AREAS OUTSIDE THE SPECIAL FLOOD HAZARD AREA
RE : CHAPTER 13 OF THE COLLEGE STATION CITY CODE
SITE ADDRESS:
Southwest Pkwy , College Station , Texas
DRAINAGE BASIN:
Main Bee Creek
DATE OF ISSUE: August 11, 2005 VALID FOR 12 MONTHS
OWNER:
7B Investments , Ltd .
1305 West Villa Maria
Bryan, Texas 77802
TYPE OF DEVELOPMENT:
SPECIAL CONDITIONS:
CONTRACTOR:
Full Development Permit
All construction must be in compliance with the approved construction plans
All trees required to be protected as part of the landscape plan must be completely barricaded in accordance with Section
7.5.E., Landscape/Streetscape Plan Requirements of the City's Unified Development Ordinance , prior to any operations of
this permit. The cleaning of equipment or materials within the drip line of any tree or group of trees that are protected and
required to remain is strictly prohibited . The disposal of any waste material such as , but not limited to , paint, oil , solvents,
asphalt , concrete , mortar, or other harmful liquids or materials within the drip line of any tree required to remain is also
prohibited .
Full Development Permit
The Contractor shall take all necessary precautions to prevent silt and debris from leaving the immediate construction site
in accordance with the approved erosion control plan as well as the City of College Station Drainage Policy and Design
Cr iteria. If it is determined the prescribed erosion control measures are ineffective to retain all sediment onsite , it is the
contractors responsibility to implement measures that will meet City , State and Federal requirements . The Owner and/or
Contractor shall assure that all disturbed areas are sodden and establishment of vegetation occurs prior to removal of any
silt fencing or hay bales used for temporary erosion control. The Owner and/or Contractor shall also insure that any
disturbed vegetation be returned to its original condition , placement and state. The Owner and/or Contractor shall be
responsible for any damage to adjacent properties , city streets or infrastructure due to heavy machinery and/or equipment
as well as erosion , siltation or sedimentation resulting from the permitted work .
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station , measures shall be taken to insure
that debris from construction , erosion , and sedimentation shall not be deposited in city streets , or existing drainage
facil ities .
I hereby grant this permit for development of an area outside the special flood hazard area . All development shall be in
accordance with the plans and specifications submitted to and approved by the City Engineer in the development permit
application for the above named project and all of the codes and ordinances of the City of College Station that apply.
Date
r& f <rz-(\) 5
Date
SUPPLEMENTAL DEVELOPMENT PERMIT INFORMATION
Application is hereby made for the following development specific waterway alterations: ~u. ~J ; J ~,r;_,,, ~--f<-•sS.~r"'.chtv
l\re. GL..,QH ACKNOWLEOGMt=NTS : '\ 'c. ,/) \..-{J . s . \,._ \..._-n._
I, .j~J r design engineer/owner, hereby acknowledge or affirm that:
The information and conclusions contained in the above plans and supporting documents comply with the
current requirements of the City of College Station, Texas City Code, Chapter 13 and its associated Drainage
Policy and Design Standards.
Property Owner(s)
As a condition of approval of this permit application , I agree to construct the improvements proposed in this
appl ication according to these documents and the requirements of pter f the ol ege Station City
Code .
Contractor
CERTIFICATIONS:
A. I, __ , certify that any nonresidential structure on or proposed to be on this site as part of this
application is designated to prevent damage to the structure or its contents as a result of flooding from
the 100-year storm .
Engineer Date
B. I, __ , certify that the finished floor elevation of the lowest floor , including any basement , of any
residential structure , proposed as part of this application is at or above the base flood elevation
established in the latest Federal Insurance Administration Flood Hazard Study and maps, as amended.
Engineer \_ ~ _) =~~ Date
C. I, 0e.jf, certify that the alterations or development covered by this permit shall not diminish the flood-
carrying capacity of the waterway adjoining or crossing this permitted site and that such alterations or
development are consiste t with requirements of the City of College Station City Code, Chapter 13
of floodways and of floodways fringes.
e; -( 2 ,-() 5
Date
D. I, __ , do certify that the proposed alterations do not raise the level of the 100 year flood above
elevation established in the latest Federal Insurance Administration Flood Hazard Study.
Engineer Date
Cond itions or comments as part of approval: ------------------------
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station , measures shall be taken to insure that debris
from construction , erosion, and sedimentation shall not be deposited in city streets, or existing drainage facilities. All development
shall be in accordance with the plans and specifications submitted to and approved by the City Engineer for the above named project.
All of the applicable codes and ordinances of the City of College Station shall apply.
SITE PLAN APPLICATlON 3of6
Special District Site Plan.doc 12/31/02
...
Date:
To:
From:
Subject:
Remarks:
TEX CON
TRANSMITTAL
August 16 , 2005
Caro l Cotter
City of College Station Development Services
Joe Schultz, P .E.~
Texcon General c'Fractors
2900-A Longmire Dri ve
Co ll ege Station, Texas 77845
Phone: (979) 764-7743
Construction Site Notice
Replat of Tract "A" The Glade Subdivision -Section 12
Co ll ege Station, Texas
Attach ed is a copy of the Construction Site Notice in accordance with th e
TPDES General P ennit TXR150000 .
;:;s prn
...
------------... "'Iii
CONSTRUCTION SITE NOTICE
FOR THE
Texas Commission on Environmental Quality (TCEQ)
Storm Water Program
TPDES GENERAL PERMIT TXR150000
The following information is posted in compliance with Part II.D.2. of the TCEQ General Permit Number
TXR 150000 for discharges of storm water runoff from construction sites. Additional information regarding the
TCEQ storm water permit program may be found on the internet at:
www.tnrcc.state.tx.us/permitting/waterperm/wwperrn/tpdestorm
Contact Name and Phone Number: ~ o Sep"'-?. Sc...kL;...\+z.. 'PE . (;}79) 70'-l-7743
I
Project Description : Re.p \,. . .+ c,~ !ro-,c..+ A ~1 lk G lt:i.<k--S1,t.J.,.d."u1'l10.,
xc, h o ""-I 2-.
(Physical address or description of the site's 5 o u..-\-\..._ we..<::. f-c ~ ~ i •·\J-v---'Se..c. +»o "'-o ~
location , estimated start date and projected end S ol..\..+l._ Woo J. D...-.'vt...--CL."'<:\.. 5,"t>u... +~we.s:f-date, or date that disturbed soils will be
stabilized) f ct_ v IL wo.../ .
Location of Storm Water Pollution -reu..ol-\..-1 Z. '706A-Lc~ M._.i'...-(._ D v--,'ve_
Prevention Plan : C....t. l\t.-~ s -hi-+i . 0 ""'---TY-77 re, L( :;--
For Construction Sites Authorized Under Part 11.D.2. (Obtaining Authorization to Discharge) the following
certification must be completed:
I ~ <u$~""-p, i ~-( +-l (Typed or Printed Name Person Completing This Certification) certify under penalty of
law that I hate read and understand the eligibility requirements for claiming an authorization under Part 11.D .2. of
TPDES General Permit TXR150000 and agree to comply with the terms of this permit. A storm water pollution
prevention plan has been developed and implemented according to permit requirements . A copy of this signed
notice is supplied to the operator of the MS4 if discharges enter an MS4 system. I am aware there are significant
penalties for providing false information or for conducting unauthorized discharges, including the possibility offine
and i prisonment for nowing violations .
Cr , f11\CV\ <./ S --/6 r 0 5
~~~'---A-=-'--'--=-...,__-=---\-\~~~-£_~~--1-~~~~~
Date
28-Jul -05
C ON STRUCTION COST ESTIMATE
THE GLADE -SECTION 12
COLLEGE STATION , TEXAS
Item Estimated Unit Estimated
No . Description Quantity Price Cost
Sitework
1 Mobilization/Layout 1 LS $3,000.00 $3,000
1 Traffic Control 1.0 LS $2 ,000 .00 $2 ,000
2 Site Preparation -street and pond area 1.0 LS $2 ,500 .00 $2,500
3 Remove existing curb and gutter 83.0 LF $12.00 $996
4 Remove existing 4' sidewalk 72.0 LF $10.00 $720
5 Remove existing brick wall and concrete footing 192 .0 LF $25.00 $4 ,800
6 Silt Fence 660 LF $2.75 $1 ,815
7 Construction Exit -Rock 20 TONS $55 .00 $1, 100
8 Erosion & Sediment Control Maintenance LS $600.00 $600
9 Hydromulch/Hydroseeding 2 ,500 SY $0.50 $1,250
10 Topsoil Stripping & Replacement 350 CY $5 .00 $1,750
11 Excavation/Grading -Street and 1,400 CY $5 .00 $7 ,000
and Pond Construction
12 Concrete Apron -6" depth 585 SF $5.50 $3 ,218
13 Sidewalk 80 SF $3 .20 $256
14 ADA Ramps 2 EA $400 .00 $800
15 Lime Stabilized Subgrade 1,700 SY $3.25 $5,525
16 Base Material -6" depth 1,375 SY $7 .00 $9,625
17 Asphalt Paving -1 1 /2" depth 1,375 SY $6.00 $8,250
18 Concrete Curb and Gutter 925 LF $8.25 ~7,631
Subtotal $62,836
Storm Drainage & Detention Pond
19 Drainage Pipe -24" RCP -Non -Structural 103 LF $50 .00 $5, 150
20 Drainage Pipe -18" RCP -Structural 60 LF $40.00 $2,400
21 Junction Box over existing 30" pipe 1 EA $3 ,000 .00 $3,000
22 Inlets -1 O' wide 2 EA $3,000 .00 $6 ,000
23 Concrete S .E.T . -24" RCP 1 EA $1 ,800.00 $1 ,800
24 Remove existing concrete flume 655 LF $2.50 $1 ,638
25 Replace existing sidewalk for Junction Box 1 LS $400.00 $400
26 Concrete riprap 50 SF $5.00 $250
27 Grass Sod 1, 128 SY $5 .00 $5 ,640
28 Pond Outlet Structure 1 LS $2,250.00 $2 ,250
29 Concrete Flume -3' wide 650 SF $5.00 ~3,250
Subtotal $31 ,778
.-...
Water
30 Remove Blow-off and Connect to Existing Line
3 1 6" Water PVC C909 -Non-Structura l 133
32 3" Water PVC CL200 (C909) -Non -Structur a l 317
33 3" 45 deg . M .J . Bends 2
34 3" Gate Valves
35 6"x3" M.J . Tee 1
36 Fire Hydrant Assembly
37 Vertica l Extens ion for fire hydrant
38 2" Blowoff Assembly 1
39 Water Services -1" Long 1
40 Water Services -1" Short 2
41 Water Services - 1 .5" Short 2
42 Water Services - 1.5" Long 4
Sewer
4 3 6" SDR26 D-3034 Pipe Non-Structural <6' deep 352
44 Manholes -<6' Depth 2
45 4" Sewer Service Single LS 1
46 4" Sewer Service Double SS 3
47 4" Sewer Service Double LS 4
48 TV inspection of sewer line 360
48 Connect to Existing Manhole 1
LS $25 0 .00
LF $22.00
LF $18 .00
EA $200 .00
EA $350 .00
EA $3 00 .00
EA $2,500 .00
EA $250 .00
EA $400 .00
EA $750 .00
EA $400 .00
EA $500 .00
EA $830 .00
Subtotal
LF $20 .00
EA $2 ,000 .00
EA $350 .00
EA $500 .00
EA $800.00
EA $3 .50
EA $1 ,000 .00
Subtotal
Total Sitework
Total Storm Drainage
Total Water
Total Sewer
TOTAL CONSTRUCTION I
REVIEWED FO R
COMPLIAN CE
AUG I I 200 5
COLLEGE STATION
ENGINEERINQ
$250
$2 ,926
$5 ,706
$400
$350
$300
$2,500
$250
$400
$750
$800
$1 ,000
$3 ,320
$18,952
$7,040
$4,000
$350
$1 ,500
$3 ,200
$1,260
$1 ,000
$18,350
$62,836
$31,778
$18,952
$18,350
$131,9151
CI TY OF CO LL ,EGE STAT IO N
/'/111111i11g & /)e11t·!op111r111 .\~;-rri(er
FINAL PLAT APPLICATION
(Check one) 0 Minor
($300 .00)
0 Amending
($300.00)
0 Final
($400 .00)
0 Vacating
($400.00)
~ Replat
($600.00)*
*In cludes public hea ri ng fee
The following items must be submitted by an established filing deadline date for P&Z Commission consideration .
MINIMUM SUB MITT AL REQUIREMENTS: ~Filing Fee (see above) NOTE : Multiple Sheets -$55 .00 per additional sheet
t.J /A Variance Request to Subdivision Regulations -$100 (if applicable)
V Devel opment Permit Application Fee of $200.00 (if applicable).
_.iL:: Infrastructure Inspection Fee of $600 .00 (appl icable if an y public infrastructure is being constru cted)
V App li cation completed in full .
~Cop y of origina l deed restrictions /covenants for replats (if applicabl e).
~ Th irte e n (13) folded copies of plat. (A signed mylar original must be submitted after staff re vi ew .)
~ One (1) copy of the approved Preliminary Plat and/or one (1) Master Plan (if applicable).
7 Paid tax certificates from City of College Station , Brazos County and College Station l .S .D.
V A copy of the attached checklist with all items checked off or a brief explanation as to why th ey a re not.
V Two (2) copies of public infrastructure plans associated with this plat (if a pplica ble).
V Pa rk land Ded ication requirement approved by the Parks & Recreation Board , pl e as e prov ide proof of
approval (if applicable). ~r--1.A.t\..v-q ~. 1-lx.Y::; ._,
Date of Preapplication Conference: ~ V\.°'-'~ 24 1..ooS:-
-~-~--.--t-~~1 ~~~-------------
NAME OF S U BDIVISION :1he bla,o\e,
1
Su_.Jj0,t) 12-Resptd of ff"-d--''A"
SPECI FIE D LOCATION OF PRO POS ED S UBDIVISION (L ot & Bl oc~).-(?.Ac} "(Jc'' ---f£rt:. Glade.. ~Im /2...
) I
APPLICAN T/PROJECT MANAGER 'S IN FORMATION (P ri mary Con tact for the Project):
Name 0-~~ l;,0 street A ddm~~s-~le$± Vltla Wk.r\CL-
sta te TX Z ip Code Jl'W I
City "B9 ttYl
E-M ai l Address
~------------
Ph one Numbe r q 11-1 7f -4 315 Fa x Nu mb er j J C[-77'1'-Q5fc,]
PROPER TY OWNER 'S INFORMATI O N:
Name 1 £:> . lx\Vesh--v-wn-k1 _L--h:£.
streetAddress [?os-IA.Jest \/ill" Wltt-n "-C ity _:B.._..._·cv~"""'.n""-· .__ _____ _
St ate T )( Z ip Cod e :Z J £>o I E-Mai l A ddress ____________ _
Ph o ne Number '"1 1<i-]J 'J -13]') Fax Num ber '11 Cf-1 7/-o3o]
ARC HI TECT OR EN GIN E ER 'S INF OR MAT IO N:
Name J.f _..Uoo -, b'f 5vh 1."J f-i.. P. E . ~ I
Street Add ress 11 Dl &a.h&Wl Rot:td City Ci?ll~e S"ta_--h'trvl .
State rx__ Zip Code 11'04:) E-Mail Ad dress jX-sch.Jf:c:E'teklo(] .Viet--
Ph one Numbe r t j]q -J lA ~ Jr4-~ Fax Number _W,_,_._-__,7'"""'f'7'"-"/f-.____-7._7-'---=S"_._1 ____ _
6 /13 103 I nl <\
Ii isr cF
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Design Report
Waterline Fire Flow Analysis
for
The Glade, Section 12
College Station, Texas
July 2005
Prepared By:
TEXCON General Contractors
1 707 Graham Road
College Station, Texas 77845
(979) 764-7743
1.0 INTROD UC TION & DES C H.I PTIO N
T he purpose of thi s re port is to p rovide a d esc rip tion o f th e propos ed wate rlin es to be
co n stru c ted with t he The Glade, Section 12, Subdivision, a nd to pro v id e th e re s ult s o f th e
anal ysis of th e wate rlin es und e r fir e fl ow co nditi o ns. A n ex is tin g 12 " waterlin e is loca ted
acro ss So uthw est Parkway from th e proj ec t s it e. T he prop osed waterline to s uppl y th e s ite
will conn ec t to th e ex istin g 6" waterline, which was s tubb ed o ut to serve this s tructure. T hi s
6" lin e conn ec ts to a 6" lin e o n G lade S treet , whi c h co nnects to the 12 " line alon g
Southwest Parkway . The water main w ill be cons tru cted us in g 6", a nd 3" diame ter pipe.
The 6" wate rlin e for thi s p roj ec t will be con stru cted of DR-14 , PVC pipe m eetin g th e
re qui rement s of AWWA C -909 wit h m ec hani ca l joint fittin gs . The 3 " wate rlin e wi ll be
SDR-21 , ASTM 2241 , and C lass 200.
2.0 FIRE FLOW REQUIREMENTS
T he flow required for fire hydrant flo w for th e s ubdivi s ion is 1,000 ga llons p er minute
(gpm), for th e propose d fire hydrant.
3.0 WATERLINE SYSTEM ANALYSIS
The waterline system was analyzed usi n g th e WaterCAD computer program d eve lop ed b y
Haestad Method s, In c. A normal domestic us e flow of 1.5 gpm was included in the a nal ys is
for each of the 15 residential lots. This results in a normal d e mand of 22.5 gpm , which was
included in the anal ys is.
Exhibit "A-1 ",in A ppendix A, presents the results of a pressure/flow test from fire h ydrants
connected an ex is tin g 8" waterline on La ura Lane, which connects to the ex isting 12 " line
along Southwest Parkway . A static pressure of 106 psi and a res idual pressure of 102 p s i
with the hy drant flow at 1,550 gpm were d e tem1in ed by Co ll ege Station Publi c Utility
personnel.
Since this flow was greater than the flo w required for thi s s ubdi v ision the residual pressure
from the test could be used . However to e nsure a conservati ve approximation of the
r es idual pressure for the fire flow analysis a residu a l pressure of 60 p si at the fire h ydra nt
where the test was p e rfonned was assume d . The h ydrauli c grad e was set at thi s pre ss ure at
the start of the waterline analysis , Junction R-1 .
The compute r m ode l was run w ith a fire flo w of I 000 g pm fo r the propo sed fir e h ydra nt.
Ex hibit A is a sc h e m at ic of th e p roposed waterline , w hi c h s hows th e loca tion s of th e fir e
h ydrant. Ex hibit Bi s a s umm a ry of th e pip e system junc ti on nodes with th e fir e flo w at th e
fir e h ydrant. The lowes t residual press ure occurre d in th e sys te m a t Junction J -9 . Th e
pressure a t thi s point is es timated by th e mode l to be 4 7 .1 psi , w hich exceed s t he minimum
of 20 p s i required b y the TCEQ regul atio ns.
Ex hi bits C & Dare s umm aries of th e pipe sections for th e system und e r this d e m a nd
scen ario. The max imum ve loc ity for th e 6", and 3" wa te rlin es is 11.6 fee t p e r seco nd ,
res pect ive ly, a nd occ ur s in Pipes P-5 , P-6 , a nd P-7. Thi s is less th a n th e 12.0 fps a ll owed b y
th e Des ig n G uid e lin e s.
A separate a na lys is wa s run for th e d o m es ti c us e o f 1.5 g pm pe r unit for th e e ntire
s ub divi s io n , a nd th e minimum res idu al p ress ur e wa s 58.6 ps i, w hi c h exce ed s th e minimum
pr e ss ur e o f 35 p s i requ ire d by TCEQ Re fe r to Ex hibit s "E", "F" a nd "G" fo r d a ta o n thi s
s ce na ri o. M in o r lo sses in thi s sys te m we re no t c;i lc ulat ccl, a s th ey we re a ss um e d to be
i n s i ~n i li c;1111 .
4.0 CONCLUSlONS
The w a te rlin e s proposed fo r thi s d eve lo pm e nt s h o uld ad e qu a te ly prov id e th e fir e fl ow
re quire d w ith a cc e pt a bl e va lu es fo r h eadl oss a n d ve locit y. T hi s a n a lys is was do n e ass umin g
a dequ a te res idual pre ssure in th e ex istin g w a te r m a ins , as d etennine d b y the fl ow tes t.
Appendix "A"
Fire Hydrant Flow Test Data
Appendix "A"
Fire Hydrant Flow Test Data
071 0 7 1 2005 13:0 2 FAA 9 7 9 764 3 4 52 COLLEGE STATCON PUB.UTL.
N ,I( College Station UtilHies ~ Reliable, AffordalJ/e, CC>mmunity Owned
1601 GRAHAM ROAD
COLLEGE STATION TEXAS 77845
Date: 7 JULY 2005
Number pages including cover sheet - 1
Fax number: 764-7759
Attention: JOE SCHULTZ
Company: TEXCON
From: Butch Willis Water Wastewater Division
Phone: 979-764-3435 Fax: 979 -764-3452
FLOW TEST REPORT
Nozzle size: 2.S inch
Location: 1800 LAURA LANE
Flow hydrant number: L=083
Pitot reading: 85
(OPM): 1550
Static hydrant number: L-054
Static PSI: 106
Residual PSI: 102
ff ,,
A -I
141001
J-9
P-9
R-1
P-1
j 1
Scenario: Base
-7
J-8 R-8
-2
J-6
J-5
-6
G-1.. .· s J-«.,,.)
{,"f_,· .. e.
f<of t>l "J
6 " u"~
-3
P-5
J-4
-4
!'11 '1'·<1 C11 q ir1 ep r : .IC>E S C H U L T Z
,, i 11••·•·'.·111 J -:1 .;·r' \/J;i l t 11•1 11\' (.-1 (\! i'!ll' \)~·;,\ (~! t ·i,r, I·.,., I ';H ;1 ' 1 •I .
Node Elevation Demand
Labe l (ft) Type
J-1 279.00 demand
J-2 278 .50 demand
J-3 278.00 demand
J-4 276 .00 de mand
J-5 2 77.00 demand
J-6 278 .00 demand
J-7 278.00 dema nd
J -8 278.50 demand
J-9 282 .00 demand
Til le: Th e C lade Sr:~c t irn1 12
1:·'d 1 ~·1 f~s 1 ;:1c~1.v:trc \c-l~~7 •.-.·1 t !
Demand
(gpm)
0.00
0 .00
0 .00
0 .00
0 .00
0 00
1 ,000 .00
0 .00
22 .50
071~'.7 /()!j 11 ::;'.!:·r;~~ :\1•.1 . •l ·;11~~;l ;H I f ·.1 1 ~:11H1'I':_ 111 1
Scen a rio: Ba se
Ste a dy State Analysis
Junction Report
Demand ~alcul a ted Hydra uli c Pressure
Pattern Demand Grade (p s i )
(gpm) (ft)
Fixed 0 00 4 16 .78 59.58
Fixed 0 .00 41 6 .32 59 .60
Fixed 0 .00 41 5 .96 59 .66
Fixed 0 00 415.53 60 .34
Fixed 0 .00 410 .22 57 .61
Fixed 0 .00 399 .18 52.40
Fi xed 1,000 .00 39 1 .31 49 .00
Fi xed 0 .00 39 1 .29 48 .77
Fi xed 22 .50 390 .83 47 .06
lT:<CO N GUJ U V\l. CO NTRA C TO l'I S
Prnjf·t:I r:-r 1 qi 1 1 (:1~r l()E SC H ULT Z
'/.";11. d .•\P v:~. 1 lff/ 1 1 I
l':1q1• 1 ri! 1
Link Length Dia m ete r Ma teria l Roughn ess M in o r Loss
Labe l (ft) (in)
P-1 83 .00 8 PV C 1 50 .0 0 00
P-2 227 .00 12 PV C 150 .0 0 .00
P-3 174.00 12 PV C 150 .0 0 .00
P-4 2 12 .00 12 PVC 1 50 .0 0 .00
P-5 89 .00 6 PVC 150 .0 0 .00
P-6 185 .00 6 PVC 150 .0 0 00
P-7 1 32 .00 6 PVC 150 .0 0 .00
P -8 1 1 .00 3 PVC 150 .0 0 .00
P -9 30 5 .00 3 PVC 150 .0 0 00
I·; ,' ,: 1 ··, I 1 ' I I , ,·, ~ .
Scenario : Base
Steady State An a lysis
Pipe Report
Init ia l C u rrent D is c h arge S ta rt
S tatu s Sta tus (gpm) Hyd ra ulic
G ra d e
(ft)
Ope n Open 1 ,022 .50 41 8 .0 0
Op e n Open 1 ,022 .50 416.78
Open Open 1 ,022 .50 4 16 .32
Ope n Open 1 ,022 .50 4 15 .96
Ope n Ope n 1 ,022 .50 4 15.53
Open Ope n 1 ,022 .50 4 10 .22
O pe n O pe n 1 ,0 22 .50 399.18
O pe n O pen 22 .50 39 1 .3 1
O pe n O pen 22 .50 39 1 .29
(' ( t
~.+h :~:+ c
End Head loss F ri c ti o n
H yd ra ulic (ft) S lope
Grade (fl/100 0ft)
(ft)
41 6.78 1 .22 14 .70
41 6.32 0 .46 2 04
415 .96 0 .36 2 .04
415 .53 0 .43 2 .04
410 .22 5 .3 1 59 .66
399 .18 1 1 .04 59 .6 6
391 .3 1 7 .88 59 .66
391 .29 0 .02 1.5 0
390 .83 0.46 1.50
1."'.' 1" ·ii·'',[-'·.<: 1 !Cit. I r 1
r '; q .• 1 1 .1 r
Analysis Results
Scenario: Base
Steady State Analysis
Tille : The Glade Section 12
Project Engineer: JOE SCHULTZ
Project Date : 07/27 /05
Comments :
Scenario Summary
Labe l Base
Demand Alternative Base-Average Daily
Physical Alternative Base-Physical
Initial Settings Alternative Base-Initial Settings
Operational Alternative Base-Operational
Age Alternative Base-Age Alternative
Constituent Alternative Base-Constituent
Trace Alternative Base-Trace Alternative
Fire Flow Alternative Base-Fire Flow
Liquid Characteristics
Liquid Water at 20C(68F) Specific Gravity 1 .00
Kinematic Viscosity 0 .1 08e-4 ft2 /s
Network Inventory
Number of Pipes 9 Number of Tanks 0
Number of Reservoirs 1 -Constant Area : 0
Number of Junctions 9 -Variable Area : 0
Number of Pumps 0 Number of Valves 0
-Constant Power: 0 -FCV's: 0
-One Point (Design Point): 0 -PBV's: 0
-Standard (3 Point): 0 -PRV's: 0
-Standard Exte nded : 0 -PSV's: 0
-Custom Extended : 0 -TCV's: 0
-Multiple Point: 0 Number of Spot Elevations 0
Pipe Inventory
Total Length
3 in
6 in
1,418.00 ft
316 .00 ft
40 6 .00 ft
B in
12 in
Pipes @ 0.00 hr
Label StatusConstituent Flow Velocity From To
(mg /I) (gpm) (fUs) Grade Grade
(ft) (ft)
P-1 Open N /A 1,022 .50 6.53 ·18.00 16 .78
P-2 Open N /A l .022 .50 2 .90 ·16 .78 16.32
P-3 Open N /Al,022 .50 2 .90 16 .32 15.96
P-4 Open N /A l,022 .50 2 .90 .15.96 15 .53
P -5 Open N /A (,022 .50 11 .60 ·15 .53 10 .22
P-6 Open N /A 1,022 50 11 .60 10 .22 ;9 9 .18
P-7 Ope n N /A l ,02 2 50 11 .60 ;99 .18 ;9 1 .3 1
P-8 Open N /A 22 .50 1 .02 ;9 1 .3 1 ;9 1 .29
P-9 Open N IA 22.50 1 .02 ;9 1 .29 ;90 .83
Tille: Ti u=! G l;:1rlt ! Secti rn 1 1 :1
Friction
Loss
(ft)
1 .22
0.46
0 .36
0.43
5 .31
11 .04
7 .88
0 .02
0.46
Minor
83 .00 ft
6 1 3 .00 ft
Total Headless
Loss HeadlosS3radient
(ft) (ft) (fV1000ft)
0 .00 1 .22 14.70
0 .00 0 .46 2 .04
0 .00 0 .36 2 .04
0 .00 0.43 2 .04
0 .00 5 .31 59.66
0 .00 11 .04 59.66
0 .00 7 .88 59 .66
000 0 .02 1 .50
0 .00 0.46 1 .50
c \h a 1.~s l ;ic l 1·..rv trr ··1~1:,1 ~'.i.1!
q/.';~'.i /(1 1 1 I I ;.'~I 1 ·-; •\rvl
r E XCON GENEf~AL. CONTflAC'I Of<S
ll;1r><:.l,•1 ! r,_.1 •. :/111tl:. lr l(
Prnj"t:I [11o i11"'" .IOE SC HULT Z
1t1.';llr •I /.\' '.,·-; I IU7 l c!
t -~ . i ~ : 1 • 1 t , I 1
Node Elevation Demand Demand
Label (ft) Type (gpm)
J-1 279 .00 d emand 0 .00
J-2 278 .50 demand 0 .00
J-3 278.00 demand 0 .00
J-4 276 .00 d emand 0 .00
J-5 277 .00 d e mand 0 .00
J-6 278.00 d ema nd 0 .00
J-7 278.00 d emand 0 .00
J-8 27 8 .50 d emand 0 .00
J-9 282.00 d ema nd 22 .50
T ill e · Tl1 e c;1;·1dn Sec li o r1 12
<.:'.I 1;•(:·:'.:l ;1d 1\/\J l1 r· 1_~ I~~-;-W I'.! I
q·;·1 ;-'/'(l,-1 1 1 ·;:1 ;"o"I ,\:,,1 I I; H •-.1, 11 ! r •. ~ • .i I 11 " " I 111
Scenario: Base
Steady State Analysis
Junction Report
Demand Calcula ted Hydraulic Pressure
Pattern Demand Grade (psi)
(gpm) (ft)
Fixed 0 .00 418 .00 60.11
Fixed 0 00 418 .00 60 .32
Fixed 0 .00 418.00 60 .54
Fixed 0 .00 418.00 6 1.4 0
Fixed 0 .00 417 .99 60 .97
Fixed 0 .00 417.98 60.53
Fixed 0 .00 417 .98 60 .53
Fixed 0 .00 417.96 60.31
Fi xed 22 .50 417 .50 58 .60
·r [ XC(IN c;r ME.l<A L CON I F<AC'I OF<S
P H•l fll"I F11~111H:l !I ..l()E ~;C H ULTZ
'.".',II! !I I. /.1 ' .. , . : 1 II ',· I I 1
:•.•111 · I 1•! I
Link Length Diame ter M a te rial
Labe l (ft) (in)
P-1 83 .00 8 PVC
P-2 227 .00 12 PVC
P-3 174 .00 12 PVC
P-4 212 .00 12 PVC
P-5 89 .00 6 PVC
P-6 185.00 6 PVC
P-7 132 .00 6 PVC
P-8 11 .00 3 PVC
P-9 305.00 3 PV C
T1fl1~: Tl1P C l<1<lf· ~::.,:·1 ·f io r 1 I :)
(. \ I I ; I! ; ~·· : ' l • !' .. : J I I I • ' I I' . ' \'.I ( . ! l
Roughn es~ Minor Los~
150.0 0 .00
150.0 0 .00
150.0 0 .00
150.0 0 .00
150.0 0 .00
150.0 0 .00
150 .0 0 .00
150 .0 0 .00
150 .0 0 .00
• 17//t/111 • 1 1 .1. 1. i'.r.1 ·; f 1 ~,,·~;1 ;11~ r .. 11 11 c ·~··· 1.,.
Scenario: Base
Steady State Analysis
Pipe Report
Initial C urrent Di sch arge S tart
Sta tu s S ta tu s (gpm) Hydrauli c
G ra d e
(ft)
Open Open 22 .50 4 18 .00
Open Open 22 .50 418.00
Open Open 22 .50 418 .00
Open Open 22 .50 418 .00
Open Open 22 .50 418.00
Open Open 22 .50 417 .99
Open Open 22 .50 417 .98
Open Open 22 .50 417 .9 8
Ope n Open 22 .50 417 .96
cf I'
f; -d~: 6: t F
End Head loss
Hydrau lic (ft)
Gra de
(ft)
418 .00 0 .1e-2
418 .00 0.4e-3
418 .00 0 .3 1e -3
418.00 0 .37e -3
417 .99 0.46e-2
417 .98 0 .01
417 .98 0 .01
417 .96 0.02
417 .50 0.46
Friction
Slope
(fl/1000 ft)
0 .0 1
0 .17e-2
0 .18e-2
0 .17e-2
0 .05
0 .05
0 .05
1.50
1.50
P r1 '1··r r l.1 1~1 i 1 1 1·f~r .I C>F SC H ULl ?
\.','; "• ·1 ! .".!, -."·: I li"I ? I · I
I ';u :1 I 1 I
Label Status Constituent Flow
(mg /I) (gpm)
P-1 Open NIA 22 .50
P-2 Open NIA 22 .50
P-3 Open NIA 22.50
P-4 Open NIA 22 .50
P-5 Open NIA 22.50
P-6 Open NIA 22.50
P-7 Open NIA 22 .50
P-8 Open NIA 22 .50
P-9 Open NIA 22 .50
Titl e : Tho G la de Secti o n ·12
Analysis Results
Scenario: Base
Steady State Analysis
Pipes@ 0.00 hr
Velocity From To Friction Minor Total
(ftls) Grade Grade Loss Loss Headloss
(ft) (ft) (ft) (ft) (ft)
0.14 418 .00 418.00 0 .1e-2 0 .00 0 .1e-2
0 .06 418.00 418.00 0.4e-3 0 .00 0.4e-3
0 .06 418.00 418.00 0 .31 e-3 0 .00 0 .3 1e-3
0 .06 418.00 418.00 0 .37e-3 0 .00 0 .37e-3
0 .26 418.00 417.99 0.46e-2 0 .00 0.46e-2
0 .26 417.99 417 .98 0 .01 0 .00 0 .01
0 .26 417.98 417 .98 0 .01 0 .00 0 .01
1 .02 417.98 417.96 0 .02 0.00 0 .02
1 .02 417 .96 417.50 0.46 0 .00 0.46
" \I
G
TE XCON G ENEl'~AI CONl HAC TCW S
Head loss
Gradient
(fV1000ft)
0 .01
0 .17e-2
0 .18e-2
0.17e-2
0 .05
0 .05
0 .05
1 .50
1.50
Proj(,C I F11q ir.,eer : .JOE SC H ULTZ
\,V:11+·1C/\l_1 v :), I [r 17 Jf ·I
Design Report
Waterline Fire Flow Analysis
for
The Glade, Section 12
College Station, Texas
July 2005
Prepared By:
TEXCON General Contractors
1 707 Graham Road
College Station, Texas 77845
(979) 764-7743
1.0 INTRODUCTION & DESCRIPTION
The pu1vo se of thi s re port is to pro v id e a d esc ripti o n of th e proposed wate rlin es to be
co ns tru c te d with th e Tile Glade, Se ction 12 , Subdivision, a nd to provi de th e re s ult s of th e
anal ysis of the waterlines und e r fir e fl ow conditions. An ex is tin g 12 " wa te rlin e is lo cated
across So uthw es t Parkway from the proj ec t s it e. The proposed waterline to s upply th e s it e
will co nn ec t to th e ex istin g 6" waterline, which was stubbed out to serve this st mcture. T hi s
6 " lin e conn ec ts to a 6" lin e on G lad e St reet, w hi c h connects to th e 12 " line along
Southwest Parkway . The water main w ill be co ns tructed usi ng 6'', and 3" diamete r pipe.
The 6" wa te rlin e for thi s proj ec t will be constructed of DR-14 , PV C pipe meetin g the
re quire m e nt s of A WW A C -909 with m ec hani ca l j o int fittin gs. The 3" wa te rlin e will be
SDR-21 , ASTM 2241, and C la ss 200 .
2.0 FIRE FLOW REQUIREMENTS
The flow required for fire hydrant flow for the s ubdivi s ion is 1,000 gallons per minute
(gpm), for the propose d fire hydrant.
3.0 WATERLINE SYSTEM ANALYSIS
The wate rline system was analyzed us ing the Wate rC AD computer program developed b y
Haestad Methods, Inc. A normal domestic use flow of 1.5 gpm was included in the analysis
for each of the 15 residential lots. This results in a normal d e mand of 22 .5 gpm , which was
included in the analysis .
Exhibit "A-1 ",in Appendix A, presents the results of a press ure/flow te s t from fire hydrants
connected an existing 8" waterline on Laura Lan e, which connects to the existing 12 " lin e
along Southwest Parkway. A static pressure of 106 psi and a residual pressure of 102 psi
with the hydrant flow at 1,550 gpm were dete rmined by College Station Public Utility
personne l .
Since this flow was greater than the flow required for this subdivision the residual pressure
from the test could be used . However to ensure a conservative approximation of the
residual pressure for the fire flow analysis a residual pressure of 60 psi at the fire hydrant
where the test wa s performed was as s umed . The hydraulic grade was set at this pressure at
the start of the waterline analysis, Junction R -1.
The co mpute r m o d e l was run w ith a fire flo w of I 00 0 g pm for the proposed fire h ydrant .
Ex hibit A is a sc he m a ti c of th e proposed wa te r! ine , w hi c h s hows th e location s of the fir e
hydrant. Ex hibit B is a summary of th e pipe system junction nod es with the fire flow at th e
fire h ydrant. The lowest residual press ure occurre d in the system at Junction J-9 . The
pressure at thi s point is estimated by th e mod e l to be 4 7 .1 psi , which exceeds the minimum
of 20 p s i require d by the TCEQ re g ulation s.
Exhibits C & D are summaries of th e pipe sec tion s for the system under this d e mand
sce nario . The ma x imum velocity for the 6'', a nd 3" waterlines is 11 .6 feet p e r second ,
respectively , and occ urs in Pipes P-5, P-6 , a nd P-7 . This is less than th e 12.0 fps a ll owed by
the Desi g n G uid e lin es.
A separate anal ys is wa s run for th e dom es ti c us e of 1.5 gp m pe r unit for th e e ntire
s ubdi v is io n, and th e minimum res idu al press ur e \Vas 58.G ps i, w hi c h exceeds th e minimum
pre ss ure o r 35 ps i required by TCEQ . Refe r to Ex hibit s "E'', "F" and "G" for data o n thi s
sce nario . M in o r lo sses in thi s sys te m we re not cal c ulat e d , a s th ey were a ss um e d to be
i ns i!,!ni ll c;1111.
4.0 CONCLUSIONS
The waterlines propose d for thi s d eve lopment should adequately provid e th e fir e n ow
re quired w ith acceptable va lu es for h ead lo ss and ve locit y . T his analysis was do n e assuming
adequate residual pressure in th e ex istin g water mains, as d e t e rmined by the now test.
Appendix "A"
Fire Hydrant Flow Test Data
Appendix "A"
Fire Hydrant Flow Test Data
071 0 7 1 2005 13:02 FAX 9 79 764 34 52 CO LLEGE STATION PUB.UTL .
(Uf ~~:~:~!,i~!~!~~~~d
1601 GRAHAM ROAD
COLLEGE STATION TEXAS 77845
Date: 7 JULY 2005
Number pages including cover sheet -1
Fax number: 764-7759
Attention: JOE SCHULTZ
Company: TEXCON
From: Butch Willis Water Wastewater Division
Phone: 979-764-3435 Fax : 979 -764-3452
FLOW TEST REPORT
Nozzle size: 2.5 inch
Location: 1800 LAURA LANE
Flow hydrant number: L=083
Pitot reading : 85
(OPM): 1550
Static hydrant number: L-054
Static P S I: 106
Residual PSI: 102
(f ••
A -I
~0 0 1
J-9
R-1
Scenario: Base
p(.,,~1~J /1
l-; ,-c. l-\ 7 6 r~ .... t
-2
Tl" •U 'r·I r;i::r-I U ·~AL CON THAC TCm S
-3
J-5
P-5
l J-4
G-1_."sh . .,,..)
{, "f_,."e.
-4
-3
r·1 ,p ii·<·I r11qir1eer : .IC>E:: ~;;c;1 tUL l Z
\,\';11r •1 C: ,''.! l '."·: I 1 t }' I ( I
·-.: f'1······.·1 11 l -~11;·1' 'lv';1 !11!11111,· c -11 '1~,"jl}I ll~·;.\ i,•··1 r,·, , .... l';!e;t · 1 I '
Node Elevation Demand
Label (ft) Type
J-1 279 .00 demand
J-2 278.50 demand
J-3 278 .00 demand
J-4 276.00 d ema nd
J-5 277.00 demand
J-6 278.00 demand
J-7 278.00 demand
J -8 278.50 demand
J-9 282.00 demand
Tit le : T l 1r~ Clack~ Sec l ion 12
1: \I 1 c·1 f~s 1 ;:1r!1 .v:1r c'.•·· 1 ~:.7 . i:.1u I
Demand
(gpm)
0.00
0.00
0 .00
0.00
0 .00
0 .00
1 ,000 .00
0 .00
22 .50
Scenario: Base
Steady State Analysis
Junction Report
Demand Calculated Hydraulic Pressure
Pattern Demand Grade (psi)
(gpm) (ft)
Fixed 0 .00 416 .78 59.58
Fixed 0 .00 416.32 59.60
Fixed 0 .00 415.96 59.66
Fixed 0 .00 415 .53 60.34
Fixed 0 .00 410 .22 57.61
Fixed 0 .00 399 .18 52.40
Fixed 1 ,000 .00 391 .31 49 .00
Fi xed 0 .00 391 .29 48 .7 7
Fixed 22 .50 390 .83 47 .0 6
lTX CO N GUJER/\l. CON l RACTO l~S
Prni<·• IF""""~'" JOE SC H ULTZ
...... ,.,, 1C•1 D v'.\ I 1n;o 1, I
Link Length Diameter Material Roughn es! Minor Los ~
L a bel (ft) (in)
P-1 83 .00 8 PVC 150.0 0 .00
P-2 227 .00 12 PVC 150 .0 0.00
P-3 174.00 12 PVC 150 .0 0 .00
P-4 212 .00 12 PVC 150 .0 0 .00
P-5 89 .00 6 PVC 150.0 0 .00
P-6 185.00 6 PVC 150.0 0 .00
P-7 132.00 6 PVC 150.0 0 .00
P-8 11 .00 3 PVC 150.0 0 .00
P-9 305 .00 3 PVC 150.0 0 .00
·1 !l it '• 'l l1 t~ (;l;i :J1• '.:~,~( l t<Ht 1:1
l ';'t ·.t to! ,'Viti 1 1 .: ,1
l/1;•./ •]'-, 11 I 1 ,· ....
Scenario: Base
Steady State Analysis
P ipe Report
Initial Current Di scha rg e Start
Status Status (gpm) Hydra uli c
G rade
(ft)
Open Open 1 ,022 .50 418 .00
Open Open 1 ,022.50 4 16.78
Open Open 1 ,022 .50 416.32
Open Open 1,022.50 415 .96
Open Open 1,022.50 415.53
Open Open 1 ,022 .50 410 .2 2
Open Open 1 ,022 .50 399 .18
Open Open 22 .50 391 .3 1
Open Open 22 .50 391 .2 9
(t t (
~..;.h :lo :+ c
End Head loss
Hydraulic (ft)
Grade
(ft)
416 .78 1 .22
416 .32 0 .46
415 .96 0 .36
415.53 0.43
410.22 5 .3 1
399 .18 11 .04
39 1 .31 7 .88
391.29 0 .02
390.83 0.46
J,t• I
Fri c tion
S lope
(ft/1 OOO ft)
14 .70
2 .04
2 .04
2 04
59 .66
59 .66
59 .66
1.50
1.50
r·1H •1··1 t f· !l<llll "~'I ,l()F SC I H JI l /
,·. ·l-·/.".f 1 . : I /'I. I
;',-t ;• ; I I
Ti tle : The Glade Section 12
Project Engineer: JOE SCHULTZ
Project Date : 07127 105
Comments:
Scenario Summary
Labe l
Demand Alternative
Physical Alternative
Initial Settings Alternative
Operational Alternative
Age Alternative
Constituent Alternative
Trace Alternative
Fire Flow Alternative
Liquid Characteris tics
Base
B ase -Average Daily
Base-Physical
Base-Initial Settings
Base-Operational
Base-Age Alternative
Base-Constituent
Base-Trace Alternative
Base-Fire Flow
Analysis Results
Scenario: Base
Steady State Analysis
Liquid Water at 20C(68F)
0 .108e-4 ft2 /s
Specific Gravity 1.00
Kinematic Viscosity
Network Inventory
Number of Pipes 9 Number of Tanks 0
Number of Reservoirs 1 -Con stant Area : 0
Number of Junctions 9 -Variable Area : 0
Number of Pumps 0 Number of Valves 0
-Constant Power: 0 -FCV's: 0
-One Point (Design Point): 0 -PBV's: 0
-Standard (3 Point): 0 -PRV's: 0
-Standard Extended : 0 -PSV's : 0
-Custom Extended : 0 -TCV's : 0
-Multiple Point: 0 Number of Spot E levation s 0
Pipe Inventory
Total Length
3 in
6 in
1,418.00 ft
316 .00 ft
406 .00 ft
8 in
12 in
83 .00 ft
6 13 .00 ft
Pipes @ 0.00 hr
Label StatusConstituent Flow Velocity From To Friction Minor Total Headloss
(mg/I) (gp m) (fUs) Grade Grade Loss LossHeadlos~radie nt
(ft) (ft) (ft) (ft) (ft) (fU 1 OOOft)
P-1 Open N /A 1,022 .50 6 .53 -18.00 -16.78 1.22 0 .00 1 .22 14.70
P-2 Open N /A l ,022 .50 2 .90 -16.78 -16.32 0.46 0 .00 0.46 2.04
P-3 Open N/A l ,022 .50 2 .90 16 .32 -15.96 0.36 0 .00 0 .36 2.04
P-4 Open N/Al,02 2 .50 2 .90 -15 .96 -15.53 0.43 0 .00 0.43 2 .04
P-5 Open N/A l ,022 .50 11 .60 -15 .53 -10 .22 5 .31 0 .00 5 .31 59 .66
P-6 Open N/A 1,0 2 2 .50 11 .60 10.22 ;99 18 11.04 0 .00 11 .04 59.66
P-7 Open N/A l ,0 22 5 0 11 .6 0 ;99 .18 ;9 1.3 1 7.88 0 .00 7 .88 59 .66
P-8 O pe n N/A 22 .5 0 1.02 ;9 1.3 1 ;9 1.29 0 .02 0 .00 0 .02 1.50
P-9 Open N/A 22 .50 1.02 ;9 1.29 ;90 .83 0.46 0 .0 0 0 .46 1 .50
(I{) ,,
f-1-h : ~ :+
Ti lle : T l·1n Gl <u:lr' S<!cti o 11 1:,i
c \h acs l ci<l'1w l rr"!! 1 ~,·1 ·""1:1 ! T[ >:CO N GE NEf<AL. CO NTRA C T O r~s
(I./.'~~ l /{ )~ 1 I I ;:·~I ~1 >: •\fv1 1 l i H ".: .. ,I rv1 1 ·ll1111b, 111 1 :: i 1.,. ,, \. su 11 • ~:.;:1 1::11·1 \,\',,l (•llnu•,·. c·1 I,,:, /I ;: l . ~:: ,''. ! '. l ~ JI : I I , , 1
Node Elevation Demand
Labe l (ft) Type
J-1 279 .0 0 demand
J-2 278 .50 demand
J-3 278 .00 demand
J-4 276.00 demand
J -5 277.00 demand
J-6 278.00 demand
J-7 278.00 demand
J-8 278.50 dema nd
J -9 282.00 demand
Titl e : Tl1 e G lad i:! Sncti o 11 12
c.'./ 1;!(·:·:t :1(!1wl1 (·1 1 ~I !:i 7 w o I
Demand
(gpm)
0 .00
0 .00
0 00
0 .00
0 .00
0 .00
0 .00
0 .00
22 .50
Scenario : B a se
Steady State Analysis
Junction Report
Demand Calculated Hydraulic Pressure
Pattern Demand Grade (psi )
(gpm ) (ft)
Fixed 0 .00 4 18 .00 60.11
Fixed 0 .00 418.00 60 .32
Fi xe d 0 .00 4 18 .00 60 .54
Fixed 0.00 418.00 61.40
Fi xe d 0 .00 417 .99 60.97
Fixed 0 .00 417 .98 60.53
Fixed 0 .00 417 .98 60 .53
Fixed 0 .0 0 417 .96 60.31
Fixed 22.50 417 .50 58 .60
.. ~ I(
HX C (lt•J GENE H A L CONTFV\C'TO H S
Pro1 1~1·t Ft l(llll (~e 1 .IOE ~:;c HULT ;~
1 .".';111~1(:/.r\ .. : 1 [C!/ 11 :1
: '. q 11 . I I,, I
Link Length Diameter
Label (ft) (i n )
P-1 83 .00 8
P-2 227 .00 12
P-3 174 .00 12
P-4 212 .00 12
P-5 89 .00 6
P-6 185.00 6
P-7 132.00 6
P-8 11 .00 3
P-9 305 .00 3
t t7(~:· ;','1 ,r·, I I .1 • ! /.f'. l
Materia l Roughn es~ Minor Los~
PVC 150 .0 0 00
PVC 150 .0 0 .00
PVC 150.0 0 .00
PVC 1 50 .0 0 00
PVC 150.0 0 .00
PVC 150.0 0 00
PVC 150.0 0 .00
PVC 150.0 0 .00
PVC 150.0 0 .00
Sc e n a rio : B a se
Steady State An a lysis
Pipe Report
Initi al Current Di scharge S tart
S ta tu s S ta tu s (gpm) H ydrauli c
Grade
(ft)
Open Open 22 .50 418 .00
Open Open 22 .50 418 .00
Open Open 22 .50 418 .00
Open Open 22 .50 418 .00
Ope n Open 22 .50 418 .00
Open Open 22 .50 417 .99
Open Open 22 .50 417 .98
Open Open 22 .50 417.98
Open Open 22 .50 4 17 .96
If I'
f1kb:+-F
End H ead loss Friction
Hydraulic (ft) S lope
Grade (ft/1 OOOft)
(ft)
418.00 0 .1e -2 0 .0 1
418.00 0.4e-3 0 .17e -2
418.00 0.31e-3 0 .18e-2
418.00 0 .37e -3 0 .17e -2
417 .99 0.46e-2 0 .05
417 .98 0 .01 0 .05
417 .98 0 .01 0 .05
417 .96 0 .02 1 .50
417 .50 0.46 1 .50
' L t• '~.I; I! ~ I'-'' I II 'I I ~ •-. '11 , ......... , I :! .. l t' .• ,•It 1!1t1 r·. ( I (' ,· 1 : 11 :-:.-, t'. r I' r,r, I···
·, ., (.•".I l ·:··: I 11 1/ 1,
l';!t :t 1 ! I
, .
Label S tatus Con stituent Flow
(mg/I) (g p m )
P-1 Open N/A 22 .50
P-2 Open N/A 22 .50
P-3 Open NIA 22 .50
P-4 Open N/A 22 .50
P-5 Open N/A 22.50
P-6 Open N/A 22 .5 0
P-7 Open N/A 22 .50
P-8 O pen N/A 22 .5 0
P-9 Open N/A 22.50
Titl e: The G lade Secl ion 12
Analysis Results
Scenario: Base
Steady State Analysis
Pipes @ 0 .00 hr
Velocity From To Friction Minor Total
(fUs) Grade Grade Loss Loss Head loss
(ft) (ft) (ft) (ft) (ft )
0 .14 418.00 418 .00 0 .1e-2 0 .00 0 .1e-2
0 .06 418 .00 418 .00 0.4e-3 0 .00 0.4e-3
0 .06 418.00 418 .00 0 .3 1e -3 0 .00 0 .3 1e-3
0 .06 4 18.00 4 18 .00 0 .37e-3 0 .00 0 .37e-3
0 .26 4 18 .00 417 .99 0.46e-2 0 .00 0 .46e-2
0.26 4 17 .99 41 7 .98 0 .0 1 0 .00 0 .01
0 .26 417 .98 4 17 .98 0 .0 1 0 .00 0 .01
1 .02 4 17 .98 417 .96 0 .0 2 0 .0 0 0 .02
1 .02 417 .96 4 17 .50 0.46 0 .00 0.46
II
G
l Ti<CON GE ND ~AI. CO NTHA C T OF~S
Headless
Gradient
(fU 1000ft)
0 .0 1
0.17e-2
0 .18e-2
0 .17e-2
0.05
0.0 5
0.05
1 .50
1 .50
\\':ti • ·1C/\l.I ·:··: I 111 7 1("1
r1;1!i1 :
Design Report
Proposed Sanitary Sewer Line Improvements
for
The Glade Subdivision
Section 12
College Station, Texas
July 2005
Prepared By:
TEXCON General Contractors
1 707 Graham Road
REVIEWED FOR
COMPLIANCE
AUG 1 1 2005
COLLEGE STATION
ENGINEERING
1.0 INTRODUCTION & DESCRlPTlON
Th e purpos e of this report is to provid e a d es cripti o n of the proposed sanitary sew e r to be
constructed with The Glade Subdivision Section 12 , and to pro v ide the criteria used in th e
design of this sanitary sewer system. The project will include the construction of
approximately 360 feet of sanitary sewer line . Th e line will connect to an existin g
manhole and will service the proposed de ve lopm e nt of The Glade Subdivision , S ection 12.
2.0 SANITARY SEWER -Design Flow and Pipe Size Calculations
The proposed sewer line is to be constructed of 6 " diameter SDR-26 pipe which meets the
requirements of ASTM-03034. The proposed manholes are 4 ' diameter manhol es , and
vary from 3.5' to 5 ' in depth, with sewer line slop es of 0.8%. The maximum distance
between manholes is less than 500 feet , as required by the Texas Commission on
Environmental Quality (TCEQ). The minimum allowable slope 6" pipe per TCEQ
requirements is 0.50%. All construction shall mee t the current City of College Station
Standard Specifications for Sanitary Sewer Construction. The sewer lin e infomrntion is
summarized in Table 1 below .
3.0 DETERMINATION OF PEAK FLOW VALUES
The peak flows were based on using a daily use of 300 gallons per day for each dwelling
unit. The design peak flow is determined by multiplying the average daily flow by 4 .0 ,
which results in the peak hourly flow. The velocities for the lines were calculated using
Manning's Equation . According to the TCEQ , the minimum velocity for sewer systems
flowing full is 2.0 feet per second. As shown in Table 1, the minimum anticipated flow
velocities for the proposed sewer lines at 50% full meet this requirement. The flow for
100% full will not be less than the flow for 50% full; therefore, the TCEQ requirement is
met. The TCEQ requires that the maximum velocity for sewer systems flow full not
exceed 10 feet per second . The values in Table 1 are well below this maximum velocity .
4.0 CONCLUSIONS
It is our det ermination based on the criteria and data deve lop ed that the propo se d sew e r
line will provide sufficient capacity for th e anticip ated wastew ater flows ge ne rat ed b y thi s
development.
Table 1 -Sewer Line Flow Data
ci Manhole No. of Units From Cumulative Average Percent 50% Full z Size Length Slope Peak Flow
QI Number Dwelling Unit Merging Dwelling Daily Flow Full Flow Velocity c:
:J From To (in) (ft) (%) Services Lines Units (gpm) (cfs) (cfs) (%) (cfs) (fps)
.... 2 1 6 3 12 .1 0 .80 15 15 3 .12 0 .00 70 0 .0278 16 .0 0 .2509 2 .6
ch 1 Exis ting 6 4 7.8 0 .80 0 15 3 .12 0 .0070 0 .0278 16 .0 0 .2509 2 .6
n =0 .013
Re fe r to co n struc tion d rawin gs for ma nh ole loca tions .
Design Report
Proposed Sanitary Sewer Line Improvements
for
The Glade Subdivision
Section 12
College Station, Texas
July 2005
Prepared By:
TEXCON General Contractors
1 707 Graham Road
1.0 INTRODUCTION & DESCRIPTION
The purpose of this report is to provide a description of th e proposed sanitary s ew e r to be
constructed wit h The Glade Subdivision Section 12 , and to provide the criteria used in th e
design of this sanitary sewer syste m . The project will includ e the co nstruction of
approx imate ly 360 feet of sanitary sewer line . The line will connect to an existing
manhole and w ill service the proposed development of The Glade Subdivision, Section 12.
2.0 SANlTARY SEWER -Design Flow and Pipe Size Calculations
The proposed sewer lin e is to be constructed of 6 " diameter SDR-26 pip e which meets the
requirements of ASTM-D3034. The proposed manholes are 4' diameter manholes , and
vary from 3 .5' to 5' in depth , with sewer line slopes of0.8%. The maximum distance
between manholes is less than 500 fe et, as required by the Texas Commission on
Environmental Quality (TCEQ). The minimum allowable slope 6" pipe per TCEQ
req uirements is 0.50%. All construction shall m eet th e current City of Co ll ege Station
Standard Specifications for Sanitary Sewer Construction . The sewer lin e inforn1ation is
summarized in Table 1 b e low .
3.0 DETERMINATION OF PEAK FLOW VALUES
The peak flows were based on using a daily use of 300 gallons per d ay for each dwelling
unit. The design peak flow is determined by multiplying the average daily flow by 4 .0,
which results in the peak hourly flow . The velocities for the lines were calculated using
Manning's Equation. According to the TCEQ, the minimum ve locity for sewer systems
flowing full is 2.0 feet per second. As shown in Table 1, the minimum anticipated flow
veloc ities for the proposed sewer lines at 50% full meet this requirement. The flow for
100% full will not be less than the flow for 50% full; therefore, the TCEQ requirement is
met. The TCEQ requires that th e maximum velocity for sewer systems flow full not
exceed 10 feet per second. The values in Table 1 are well below this maximum vel ocit y.
4.0 CONCLUSIONS
It is our detern1ination based on the criteria and data developed th a t the proposed sewer
line will provide s uffici ent capacity for the ant icip ated wastewater flows generated by thi s
development.
Table 1 -Sewer Line Flow Data
0 Manhole No. of Unil s Fr om Cumulative Average Percent 50% Full z Size Length Slope Peak Flow
Q) Number Dwelling Unit Mergln g Dwelling Daily Flow Full Flow Velo city c
:J From To (in) (ft) (%) Services Lines Units (gpm) (els) (els) (%) (els) (fps)
...... 2 1 6 312.1 0 .8 0 15 15 3 .12 0 .0070 0 .0278 16 .0 0 .2509 2 .6 .;, Existing 6 47.8 0 .8 0 0 15 3 .12 0 .0070 0 .0278 16 .0 0 .2509 2 .6
n = 0.013
Refer to construction drawings for m a nhole loca lio n s .
t' ..
Drainage Report
for
The Glade Subdivision, Section 12
College Station, Texas
July 2005
R evised July 2005
Developer:
7B Investi11er ts , Ltd.
1305 West Vi lla Maria
Bryan, Texas 77801
(979) 779-93 75
Prepared Bv:
T X ON GeneTa"I Contractors
1707 Graham Road
ollege Station, Texas 778 45
(979) 76 -774
' .
, '
'» ,.
I
I
I
CERTIFICATION
I, Joseph P. Schultz, Licensed Professional E ng in eer No. 65889 , State of Texas , cert ify th at
this revised report for the drainage d es ig n for Tlt e Glade Subdivision, S ection 12 , was
prep ared by m e in acco rdanc e with th e provisions of the City of Co ll ege Station Drainage
Policy and Design Standards for th e owners h ereof.
TABLE OF CONTENTS
DRAINAGE REPORT -REVISED 712005
THE GLADE SUBDLVrSCON, SECTION 12
CERTIFICATION .................................................................................................................................................................. 1
TABLE OF CONTENTS ........................................................................................................................................................ 2
LIST OF TABLES .................................................................................................................................................................. 2
INTRODUCTION ................................................................................................................................................................... 3
GENERAL LOCATION ANO DESCRIPTION .................................................................................................................. 3
FLOOD HAZARD INFORMATION .................................................................................................................................... 3
DEVELOPMENT DRAINAGE PATTERNS ....................................................................................................................... 3
DRAINAGE DESIGN CRJTERJA ........................................................................................................................................ 3
STORM WATER RUNOFF OETERMINATION .............................................................................................................. .4
DETENTION FACILITY DESIGN ..................................................................................................................................... .4
STORM SEWER DESIGN .................................................................................................................................................... 6
CONCLUSIONS ..................................................................................................................................................................... 6
APPENDIX A .......................................................................................................................................................................... 7
Storm S e wer Inlet Design Calculations
APPENDIX B ........................................................................................................................................................................ 10
Storm S e we1 ; Pipe Design Calculations
APPENDIX C ........................................................................................................................................................................ 15
Figure 1 -Required Detention Storage,
Pond Area-Capacity Data, Depth-Discharge Data & Storage Routing Analysis Parameters
APPENDIX D ........................................................................................................................................................................ 19
Storage Routing Analysis -Detention Pond
EXHIBIT A ............................................................................................................................................................................ 30
Pre-D e velopment Drain(Jge Are([ M(/p
EXI-IIBIT B ............................................................................................................................................................................ 32
Post-D evelopment Drain(Jge Are(/ M(/p
LIST OF TABLES
TABLE l -Rain fa ll Intensit y C alculations ....................................................................................... 4
TABLE 2 -Pre -& Post-Dev e lopm e nt Runoff Information ............................................................. 4
TAB LE 3 -Pr e -& Po s t-D e ve lo pm ent Peak Di sc har ge Co mpari so n -De te nti o n Pond Des ign ...... 5
TABL E 4 -Summ ary o f Max imum Po nd Water Leve ls ............................................................... 5
I
INTRODUCTION
DRAINAGE REPORT -REVISED 712005
THE GLADE SUBDIVISION, SECTION 12
The purpose of this revised report is to provide the hydrological effects of the construction
of The Glade Subdivision, Section 12 , and to verify that the proposed storm drainage
system meets the requirements set forth by the City of College Station Dra inage Policy and
Design Standards.
GENERAL LOCATION AND DESCRIPTION
The project is located on a 3 acre tract located on Southwest Parkway north of the
Southwood Drive intersection in College Station, Texas. The site is predominantly open
with a few trees. The existing ground elevations range from Elevation 278 to Elevation
286 . The general location of the project site is shown on the vicinity map in Exhibit A.
FLOOD HAZARD INFORMATION
The project site is located in the Bee Creek Drainage Basin. The site is located in a Zone X
Area according to the Flood Insurance Rate Map prepared by the Federal Emergency
Management Agency (FEMA) for Brazos County, Texas and incorporated areas dated July
2, 1992, panel number 48041CO144-C . Zone X Areas are determined to be outside the
500-year floodplain .
DEVELOPMENT DRAINAGE PATTERNS
Prior to development, the storm water runoff flows to the east into the Southwest Parkway
right-of-way or into an existing concrete drainage flume, which discharges into the
Southwest Parkway right-of-way. The runoff flowing into the street enters the existing
inlets and storm sewer system. Ultimately, this runoff flows into Bee Creek .
DRAINAGE DESIGN CRITERIA
The desi g n p a ram e te rs for the sto1m s ew e r and d e te ntion facilit y a nal ys is a r e as follow s:
• The Rational Method is utilized to detem1ine peak storm water runoff rate s for the
storm sewer d e si g n and the detention facility design.
• Design Stom1 Frequency
Storm sewer system
Detention facility analysis
• Runoff Coefficients
Pre -d e velopment
10 and 100-year stom1 events
5, 10, 25, 50 and 100-year stom1 e vents
Post-d eve lopm e nt (sin g le family res id e ntial)
c = 0.40
c = 0 .60
• Rainfall int e n s it y e quations and valu es for Br azo s County ca n b e found in T abl e I .
• Tim e o f Co ncentra ti o n , l e -Du e to th e s mall dra ina g e areas , a minimum le o f 10
minut es is use d to d e te rmin e th e ra infa ll int e ns it y valu es.
I
STORM WAT E R RUNOFF DET E RMI NATION
The pea k ru noff va lu es we re cl ete rrnin ecl in acco rdance w ith the c rit e ri a p rese nted in t he
prev iou s sect io n for th e 5, 10 , 25, 50, and I 0 0 -year sto rm events. T he d ra in age areas fo r
the pre-& pos t-deve lo pm e nt conditi o ns fo r th e d ete ntion pond a na lys is are s how n o n
Ex hibits A & B, resp ec ti ve ly. Th e drain age ar eas for th e po st-d eve lopm ent co nditi o ns fo r
the s to1111 sewer d es ign are show n o n Ex h ib it B. Pr e-and post -d eve lo pm ent run off
co ndition s are s umm ari ze d in Ta bl e 2 . Du e to th e s m a ll si ze of th e d ra in age areas fo r thi s
si te, a tim e of co nce nt ra ti o n of 10 minu tes has bee n use d fo r a ll of th e dra inage a reas .
TABLE 1 -Rainfall Intensity Calculations
Rainfall Intensity Values (in/hr)
Storm t -c -
Event 10 min
Is 7 .693
110 8.635
l 2s 9.861
l so 11.148
1100 11 .6 3 9
Bra zos Co unty:
5 year storm 10 year storm
b = 76 b= 80
d= 8 .5 d= 8 .5
e = 0 .785 e = 0 .763
I = b I (tc +d)0
I = Rainfall Intensity (i n/hr)
tc = L/(V*60)
tc = Tim e o f c once ntration (min)
L = L e n g th (ft)
V = V e locity (fUs e c)
25 year storm 5 0 year storm 100 year storm
b= 8 9 b = 98 b= 9 6
d= 8 .5 d = 8 .5 d = 8.0
e= 0 .7 54 e = 0 .7 45 e = 0.730
(Data ta k en from Sta te Department o f Highways and Public Transp ortation Hydrau lic Manual , page 2-16 )
TABLE 2 -Pre-& Post-Development Runoff Information
Area 5 year storm 10 year storm 25 year storm 50 year storm 100 year storm c le Area# (acres) Is Os 110 0 10 l2s 0 2s lso O so
A (min) (in /hr) (cfs) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs)
Pre-Development Drainage Area
101 3 .00 0.40 10 7 .693 9 .23 8 .635 10 .36 9 .861 11.83 11 .148 13.38
Pos t-Deve lopm ent Drainage Areas
20 1 1.14 0 .60 10 7 .693 5 .26 8 .635 5 .9 1 9 .86 1 6.75 11 .148 7 .62 --
202 0 .79 0 .6 0 10 7 .693 3 .65 8 .635 4 .09 9 .86 1 4 .67 11.148 5 .28 -----------
20 3 0 .50 0 .6 0 10 7 .693 2 .31 8 .635 2 .59 9 .86 1 2 .96 11 .148 3 .34 ---------------
204 0 .57 0 .60 10 7 .693 2 .63 8 .635 2 .95 9 .86 1 3 .37 11 .148 3 .8 1 -----
201 & 20 2 1.93 0 .60 10 7 .693 8 .9 1 8 .635 10.00 9 .861 11 .42 11 .148 12 .91 --
20 1,202 ,203 2.43 0 .60 10 7 .693 11 .22 8 .635 12 .59 9 .861 14 .38 11.148 16 .25
D ET EN TION F AC ILITY D E SIGN
Due to th e inc re ase in th e peak ru noff clu e to thi s deve lo pm ent, a de te nt ion lac i li ly is
nee ded !or the run off t hat flow s int o the So uth wes t Pa rk way ri gh t-o f-w ay.
1100 0 100
(in /hr) (cfs)
11 .639 13 .97
11 .639 7 .96 -----
11 .639 5 .52 ----
11 .639 3.49 --
11.639 3 .98 ----
11 .639 13.48
11 .639 16 .9 7
The desi gn storm for the detention facilit y is th e I 00-yea r s torm eve nt. The det e nti o n pond
is lo cated in the no rth e ast corner of th e tract adjacent to Southwest Park wa y . T h e peak
runoff values we re determined in accordance with the cr it e ri a presented in prev ious
sect ions for the 5, I 0, 25 , 50 & I 00-year sto rm events for pre-deve lopm e nt cond it ion s.
Tab le 2 shows a summary of these res ults . The post-deve lopment p eak runoff val ues a re
also summarized in Table 2. Figure 1 in Appendix C shows the required detention storage
vo lum e for the pond for the l 00-year stom1 event.
TABLE 3 -Pre-& Post-Development Peak Discharge Comparison -Detention Pond Design
Item Location O s 010 0 25 Oso
(cfs) (cfs) (cfs) (cfs)
Pre-Development
A Total Discharge From Site (Area 101) 9 .23 10.36 11 .83 13 .38
Post-Development without a Detention Pond
B Total Discharge From Site (Areas 20 1-2 04) 13 .85 15 .54 17 .75 20 .05
Post-Development with Pond
C1 Into Pond (Areas 201-20 3) 11.22 12.59 14 .38 16.25
C2 Out of Pond (Appendi x D) 6.09 6.32 6 .64 6.98
CJ Discha rge Into Southwest Pkwy -Area 204 2.63 2.95 3 .37 3.81
C4 Discharge Into Southwest Pkwy -Inlet 2 Bypa ss 0.00 0.00 0.16 0 .87
c Total Post-Development Discharge From Site (C2+C3+C4) 8.72 9 .27 10 .17 11 .66
D Decrease in Runoff From Pre-Development (A-C) 0.51 1.09 1.66 1.72
The pond outlet structure is a concrete riser structure which is 3.5'x3.5' in size, 4.0' hi g h ,
and with a 2.5'x2.5' opening at its top . There is an 12" high by 8" wide opening in the
front face of the structure with its invert at E levation 272.0 to control the flow. The
discharge pipe is an 18 " reinforced concrete pipe, 28 feet in length, which discharges into a
junction box to be constructed on an existing 30" stom1 sewer pipe. The pipe h as a design
slope of 1.0%. The top of the pond berm is at Elevation 278.0. There is a 5' overflow
spillway on the top of the berm with a flowline elevation of 277.5.
As shown in Table 3, the peak outflows from the d etention facilities are less than the
allowable peak outflow for the design stonn event. Additionally, Table 4 presents the
maximum water surface in th e ponds for the 100-year storm event, as we ll as the a mount
of free bo ard provided.
TABLE 4 -Summary of Maximum Pond Water Levels
Location 0100 Max. Water Surface Top of Berm Freeboard, ft.
(cfs) Elevation, ft. Elevation , ft .
Pond 8.54 277.2 278.0 0 .8
T h e area-capacity dat a, th e depth-discharge data a nd the Storage Routin g Analysis
Parameters for th e propo sed detention pond is pro vided in Appe ndi x C. Only 90 % of the
design volume was used for th e Storage Routing Ana lys is.
The peak now out of the detention facilit y was d etermin ed b y a S tor age Routin g A na lysi s
ba s ed on the Co ntinuit y Equ atio n as follO\vs : (11 +12 )+((2s 1/dt)-0 1 )=((2 s 2/dt)+02). The
tim e int e rva l, cit , used wa s I minut e. Th e c a lc ul at ion s and re s u lt s of th e Sto r<1g c Ro utin g
.i\1 1:1!\'s i s arc pro v id ed in App c ncl1 x D .
0100
(cfs)
13.97
20 .95
16.97
8.54
3.98
1.14
13.66
0.31
I
I
A 3' wide co ncre te lo w flow flum e is prop osed to carry the fl ow in th e d e te nti on pond to
th e pond out le t s tructure. Bl ock sod g rass will b e pl ace d in th e d e te ntion pond to co ntrol
eros ion.
STORM SEWER DESIGN
The storm sewer piping for this project has bee n se lected to be Reinforced Concrete Pip e
(RCP) m eeti ng the requirem e nts of ASTM C-76 , C lass m pip e m eeting the re quire m e nt s
of ASTM C -789 . The curb inlets will b e cas t-in-pl ace concrete .
Appendix A presents a summary of the stom1 sewer in let desi gn parameters and
calculations . The inlets were designed based on a 10 -year desi g n storm.
Inlets for the residential streets were located to maintain a gutter flow depth of 5" or less .
This design depth will prevent the spread of water from reaching the crown of the road for
the 10-year storm event. Refer to Appendix A for a summary of the gutter flow depths .
The runoff intercepted by the proposed storm sewer inlets was calculated using the
following equations . The depth of flow in the g utt er was determined by using the Straight
Crown Flow equation. The flow intercepted by Inlets 1 & 2 was calculated by using the
Capacity of Inlets On Grade equation. These equations and resulting data are summarized
in Appendix A. There are no Inlets In Sump for this project. The area between the right-
of-way and the curb line of the streets will be graded as necessary to provide a minimum of
6" of freeboard above the curb line. This wi ll ensure that the runoff from the 100-year
storm event wi ll remain within the street right-of-way .
Appendix B presents a summary of the stonn sewer pipe design parameters and
calculations. A ll pipes are 18 " in diameter or larger. For pipes with 18" and 24"
diameters, the cross-sectional area is reduced by 25%, as per College Station requirements.
A summary of how this was achieved is shown in Appendix B as well. The pipes for the
storm sewer system were designed based on the 10 -year storm event, and they will also
pass the 100-year storm event. Based on the depth of flow in the street determined for the
100-year storm event, this nmoffwill be contained wit hin the street right-of-way until it
enters the stom1 sewer system . As require d by College Station , the velocity of flow in th e
sto nn sewe r pipe system is not lower th an 2.5 feet per second , and it do es not exceed 15
fee t per second . As the d a ta s ho ws, even durin g low flow conditions , th e ve locity in th e
pipes will exceed 2 .5 feet per second and prevent sed iment build-up in the pip es . The
maximum flow in the storn1 sewer pipe system will occur in Pipe No . 2. The max imum
ve locity for the pipe system in this development will be 6 .5 feet per second and w ill occur
in Pipe No . 2. Appendix B contains a summary of the pipe calcu lations .
CONCLUSIONS
The construction of thi s proj ec t will increase th e storm water runoff from thi s s it e. The
pro pos ed s to rm sewer syste m sho uld adeq uat e ! y co ll ec t a portion of th e runoff a nd re lease
it into th e d e te nti o n p o nd . The increased runoff has bee n red uced b y th e prop osed
deten tion fac ilit y, and th e re s hould be no flood d a m age to do wnst re am or adjac e nt
landow ne rs res ultin g from thi s d eve lo pm e nt.
I>
I
I
APPENDIX A
Storm Sewer Inlet Design Calculations
The Glade Subdivision
Depth of Flow in Street Gutter
Revised 712005
Gutter A c Location (acres)
A 1 1.14 0 .6
A2 0 .79 0 .6
Tra nsve rse (Crown) slope (fl/ft)
fo r 27' stree t = 0 .0330
Slope
(ft/ft)
0 .0 110
0 .0110
10 -year storm
0 10 Y 10-ac tual
(cfs) (ft) (in)
5.91 0.348 4 .17
4 .09 0 .303 3.64
Straight Crown Flow (Solved to find actual depth o
Q = 0 .56 * (z/n) * S112 * y8 '3 ¢ y ={QI [0 .56 * (z /n)
f flow i n gutter, y:}:
n =Roughn ess Coefficient = 0 .01 8
S = StreeUGutter Slope (fUft)
y = Dep th of fl ow at inl et (ft )
z = Reci pro cal of crown slo pe:
for 27' st ree t = 30
* s1/2 ]}3/8
-
100 -year storm
0 100 Y 100
(cfs) (ft) (in)
7 .96 0 .389 4 .67
5 .52 0 .339 4 .07
!
I
I
i
The Glade Subdivis i on
!nlet Le ngth Calculations
Revised 712005
Inlets On Grade 10 year storm
Fk>wfrom y ,. O per1oo1 O c.mp.:1" a.,,, •• O uptUl'"..t llllC I T: Lr:ngth
1
·,
10'
10'
Area# (ft) I (i n)
202 ~303 _1~ --201 0.348 4.17
Transve rse !Crown) slope (ft/ftl
for 27' street = 0 .033
(ft) (cfs) (cfs )
0.60 5.97 -1.88
0.64 6.41 -0 .50
Straight Crown Flow (Solved to find actua l depth of flow. yl :
Q = 0 .56 • (z/n) • S 112 • y'" Q y ={Q I [0 .56' (z/n) • S 112])3"
n =Roughness Coefficient= 0 .018
S = StreeVGutter Slope (tuft )
y = Depth of flow at inl et (ft )
Capaci ty of Inlets on grade:
Oc = 0.7 • (1 /(H , • H2 )] • [H/12 • H2
512]
Oc = Flow capacity of inlet (cfs)
H1 =a+y
H, =a =gutter depression (2" Standard ; 4" Recessed)
y = Depth of flow in approach gutte r (ft )
(cfs )
4.09
5.91
a.,.,,.,_ a.,,,.. ... O e11pt-1:ot1 0 10 -Tot• Y100
(cfs) I from Inlet t (cfs) (cfs) (cfs) (ft) I (I n)
I 0.00 4.09 4.09 o.339 I 4.07
I 0.00 5.91 5.9 1 o.389 I 4.67
z = Re ci procal of crown slope
for 27' street = 30
Inlets in sumps, Weir Flow :
L = QI {3 ' y 312 ) Q y = (QI 3L)213
L = Length of inlet opening (ft)
Q = Flow at inlet (e l s)
y = total depth of flow on inlet (ft )
ma x y for in let in sump = 7" = 0 .583 '
O pw1oot O upmcuy
(ft) (cfs )
0.63 ~
0.68 6.82
100 year storm
a.,,, •• Oc1191ured Cc .,,.,_ 0 11yp.1ot• O c11pMoll 0 100.Tot.i s . L11C1u-"'
(cfs) (cfs) (cfs) j fromlnlel# (cfs ) (cfs ) (e ls) (tuft) (ft)
-0.80 5.52 0.00 5.52 5.52 0.0 11 0 10 -· --
1.14 6.82 I 1.14 6.82 7.96 0.0110 10
APPENDIXB
Storm Sewer Pipe Design Calculations
I
·11
Th e Glade Subdivision
Pi pe Calculations
Revised 712005
Inlet Outlet 1 O year storm 100 year storm
Pi pe# Size Length Slope
Invert Elev Invert Elev *Actual Flow Design Flow V 10 Travel Time, t11o *Actual Flow Design Flow V 100 % Full
(in) (ft) (%) (ft) (ft) (cfs) (cfs) (fps) (sec) (min) (cfs) (cfs) (fps)
2 24 102.9 0.80 274 .58 273 .76 10.00 16.15 6 .7 71.4 15 0.26 12.34 19 .93 6 .7 --
3 18 31 .0 1 .20 275.39 275 .02 5.91 9 .54 6 .8 73.7 5 0 .08 6.82 11 .01 6 .9
·The se values reflect the actual flow for the 18" & 24" pipes . The design flow for these pipe s iz es reflects a 25 % red uct ion in pipe area .
(Re fe r to attached calculation for specific information .)
% Full
89.0 ----
85 .0
Travel T ime , t1100
(sec) (min)
15 0 .26 --
4 0 .0 7
City of College Station requirement to Reduce Cross -Sectional Area of 18" & 24" Pipes by 25%
Usin g Mannings Equation from page 48 of th e Co ll ege Stati on Drainag e Pol icy & Desig n Standards Manu a l :
Q = 1.491n *A * R213 * S 112
Q =Flow Capacity (cfs)
18" Pipe:
Pipe size (inches) = 18
Wetted Perimeter WP , (ft)= 4.71
Cross-Sectional Area A , (ft2 ) = 1.766
Reduced Area A R, (W) = 1 .3 25
Hydraulic Rad ius R = NWp. (ft)= 0 .3 75
Reduced Hydr Radius R R= A R/Wp. (ft)= 0.281
Roughness Coefficient n = 0.014
Friction Sl ope of Conduit Sr . (tuft) = 0 .01
Example Calculation :
Slope Flow Capacity R educed Flow Capacity % Difference
s Q O reduce d O reduced /Q
0 .005 6 .91 4.28 0.619 -0 .006 7 .57 4 .69 0.619 -0 .007 8 .18 5 .06 0.619
24" Pipe:
Pipe size (inches) = 24
Wetted Perimeter WP , (ft)= 6 .28
Cross-Sectional Area A , (W) = 3.14
Reduced Area A R, (ft2 ) = 2 .355
Hydraulic Rad ius R =NW µ. (ft)= 0 .5
R e duce d Hydr Radius R R= A R/Wp. (ft)= 0.375
Roughness Coefficient n = 0.0 14
Friction Slope of Conduits,. (ft/ft)= 0.0 1
Example Calculation :
Slope Flow Capacity R educed Flow Capacity % Difference
s Q Oreduced O reduced /Q
0 .005 14 .89 9.22 0.619 -----0 .006 16 .31 10 .1 0.619 ------------------0 .007 17.61 10 .9 0.619
Conclusion :
Multiply actua l Q in 18" & 24 " pipes by 1.615 to reflect a 25 % red u c ti on in the
cross-sectio nal area called for on page 4 7 , paragraph 5 of the Col lege S ta tion
Drai n age Policy & D esign S ta nd a rd s manual.
Pipe 2 -10 Year Storm
Mann ing Pipe Calculato r
Gi v en Input Data:
Shape .......................... .
Solv ing for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results :
Depth .......................... .
Area ........................... .
Wetted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full flow velocity ............. .
Circular
Depth of Flow
24 .0000 in
16 .1500 cfs
0.0080 ft/ft
0 .0140
17 .1467 in
3.1416 ft2
2.4015 ft2
48 .337 5 in
75 .3982 in
6.7250 fps
7.154 2 in
71.4446 %
18.7888 cfs
5.9807 fps
Pipe 2 -100 Year Storm
Manning Pipe Calculator
Give n Input Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning' s n .................... .
Computed Results:
Depth .......................... .
Area ........................... .
Wet ted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full fl ow ve locity ............. .
Th e GJade Subdi v isi o n
Col l eqe ~;1 2 it· i n,.1. T f<•:,-,,,
H:..::'1·.i .;r l :·r 1_1
Circular
Depth of Flow
24.0000 in
19.9300 cfs
0.0080 ft/ft
0.0140
21.3713 i n
3.1416 ft2
2.9547 ft2
59.207 2 in
75 .3982 in
6.7451 fps
7.1863 in
89.0 471 %
18.788 8 cfs
5 .9807 fps
Pipe 3 -1 0 Year S t o rm
Mann i ng Pipe Calculator
Given Input Data:
S h ape .......................... .
Solvi ng for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Man ning's n .................... .
Computed Results:
Depth .......................... .
Area ........................... .
Wetted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full flow velocity ............. .
Ci rcular
Depth of Flow
18 .0000 in
9.5400 c f s
0.0120 ft/ft
0. 0140
13 .2613 in
1 .7 671 ft2
1 .3956 ft2
37.1527 in
56 .5487 in
6.8357 fps
5.409 2 in
73.6741 %
10.6850 cfs
6.0465 fps
Pipe 3 -100 Year Storm
Manning Pipe Calculator
Given Input Data:
Shape .......................... .
Solvi ng for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results:
Depth .......................... .
Area .......................... · ·
Wetted Area .................... .
Wetted Perimeter ............... .
Perime te r ...................... .
Ve locity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrat e ............. .
Full flow velocity ............. .
T h e Glade Su bdi v is i o n
Co l l e c.:w ~;1.:1t i o n. 'T'e :·:c-,,
kc:\· .i ,_; r_ l .. 1.1 11'.
Circular
Depth of Flow
18.0000 in
11.0100 cfs
0.0120 ft/ft
0. 0140
15.2995 in
1.7671 ft2
1.6009 ft2
42 .230 1 in
56.5487 in
6 .8 774 fps
5.4588 iri
84.9973 %
10.6850 cfs
6.0465 fps
APPENDIX C
Figure 1 -Required Detention Storage,
Pond Area-Capacity Data, Depth-Discharge Data & Storage Routing Analysis Parameters
I ·'
The Glade Sub d ivision
Figure 1 -Required Detention Storage
25 ~--------· -----
0p05t = 20 .95 cfs
20
15
<n -..!:..
a
i
0 u::
-" C1l
C1I a.
10
5
0 .r------------,---------------.------------~
0 10 20 30
Time of Con cen trati o n, t c (min)
The Glade S ub division
Detention P ond A rea-Capacity & Depth -D ischarge D ata
Revised 712 005
V = H * {[A1+A2 + (A 1*A2)112 ] / 3}
V = volum e, ft 2
A= area , ft 2
H = difference in elevation , ft
D ETE NT ION POND
Area -Capacit Data
Elev ation Dept h Area V o l ume Cumu l ative 90 %
Volu me Cum ul at ive
(ft) (ft) (ft2) (ft3) (ft3) (ft3)
272 0 0 0 .00 0 .00 0 .00
---273 .00 -----·-·-----
1.00 92 .0 6 30 .69 30 .69 27 .62 -------------
274 .00 1.00 496 .52 267.46 298.15 268.33
----·-------------
275.00 2 .00 1,290.41 862.46 1160 .60 1044 .54 ----------------------·--
276 .00 3.00 _?_._~1_;85 __ 1813.03 2973 .64 2676.27
277.0 0 4 .00 3,755 .52 3048 .16 6021.79 5419 .62 ---278.00 5 .00 5, 195 .97 4456 .30 10478.10 9430.29
D ETEN TION PON D
Depth -Discharge Data
E lev ation 8" W eir 8 "x 12" Orifice Opening 18" RCP Max Flow from Outlet
Depth Flow De pth Fl ow De pth
(ft) (ft) (cfs) (ft) (cfs) (ft)
272.0 0 0 0 0 0 0 ----------------
273 .00 1.0 2 0.5 2.28 --------------
274 .00 --1.5 3.94 ------------>---------
275 .00 --2 .5 --------------
276 .00 --3.5 ------277.00 ---
278 .00 --
-. . _3(. Weir Flow Equation . Q -3.0 L y
Orifice Flow Equation : Q = 4 .82 *A• y112
4 .5
-
5.08 ----------- -
6.01 ------
6.82 -----
-6.0
Fl o w Structure
(cf s) (cfs)
0 0 ----------2 .00 --------
-3.94 -
-5.08 ---------6.01
-6.82 ---19 .80 19.80
Note: When the depth in the pond exceeds Elevation 277 .0, the 18" outlet pipe becomes
the flow control structure for the pond .
-
--
t=60s
The G lade Subdivision
Storage R out ing Analysis Param
Revised 712005
Detention Po nd No. 1
Elevation Depth Discharge Storage
ft ft a. cfs s, cf
272.00 0 .00 0 .00 0 .00
273 .00 0.00 2 .00 27 .6 2 -
274.00 1.00 3.94 268 .33 --··--275.00 2.00 5.08
eters
2 sit
0 .00 - -0 .92 --8 .94 --·---34.82 ---· ·-------_ 1_.~i -53 ·-·-276.00 4 .00 6.01 ~~676 :_2 7
277 .00 5 .00 6.82 ~'!_!~62 -----------
278 .00 6 .00 19.80 10,478.10
18" Outlet Pipe
3 .5'x3 .5' Concrete Riser w/ 12" high x 8" wide opening
Opening flowline Elev . = 272.0
Top Elev.= 277 .0
89.21 ---180 .65
349.27
-
2 sit+ 0
0 .00
2.92 ---12 .88
39 .90 --· -95 .2 2 --187.47 ---369 .07
APPENDIXD
Storage Routing Analysis -Detention Pond
1 1 1
Time (min.) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Inflow (cfs) 0.00 1.12 2.24 3.37 4.49 5.61 6.73 7.85 8.98 10.10 11.22 10.66 10.10 9.54 8.98 8.42 7.85 7.29 6.73 6.17 5.61 5.05 4.49 3.93 3.37 2.81 2.24 1.68 1.12 0.56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Storage Routing Analysis Detention Pond 1 5-Year Storm Event 11+12 (cfs) 0.00 1.12 3.37 5.61 7.85 10.10 12.34 14.59 16.83 19.07 21.32 21.88 20.76 19.64 18.51 17.39 16.27 15.15 14.03 12.90 11. 78 10.66 9.54 8.42 7.29 6.17 5.05 3.93 2.81 1.68 0.56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 00 0.00 0 00 0.00 2s/t-O 0.00 -0.41 -1.09 -0.10 1.87 4.44 8.57 14.41 21.81 30.69 41.45 52.38 61.86 69.93 76.65 82.06 86.26 89.28 91.14 91.87 91.48 90.00 87.44 83.82 79.23 73.72 67.30 60.01 51.89 42.95 33.23 23.63 14.84 6.80 1.29 -0.48 0.18 -0.07 0.02 -0.01 0.00 0.00 0.00 0.00 0.00 0.00 Outflow Storage Depth Elevation 2s/t+O (cfs) if.fl illl illl 0.00 0.00 0 0.0 272.0 1.12 0.77 11 0.1 272.1 2.95 2.02 28 0.6 272.6 4.52 2.31 66 0.7 272.7 7.75 2.94 144 1.0 273.0 11.97 3.76 246 1.9 273.9 16.78 4.10 380 2.1 274.1 23.16 4.37 564 2.4 274.4 31.24 4.71 796 2.7 274.7 40.89 5.10 1,07 4 3.0 275.0 52.01 5.28 1,560 3.2 275.2 63.32 5.47 1,736 3.4 275.4 73.13 5.64 2,025 3.6 275.6 81.49 5.78 2,271 3.7 275.7 88.45 5.90 2,476 3.9 275.9 94.04 5.99 2,642 4.0 276.0 98.33 6.04 2,769 4.0 276.0 101.41 6.06 2,860 4.1 276.1 103.30 6.08 2,917 4.1 276.1 104.04 6.09 2 939 4.1 276.1 103.65 6.08 2,927 4.1 276.1 102.14 6.07 2,882 4.1 276.1 99.54 6.05 2,805 4.0 276.0 95.85 6.02 2,695 4.0 276.0 91.12 5.94 2,555 3.9 275.9 85.41 5.85 2,387 3.8 275.8 78.76 5.73 2, 191 3.7 275.7 71.22 5.61 1,969 3.5 275.5 62.82 5.47 1,721 3.4 275.4 53.57 5.31 1,448 3.2 275.2 43.51 5.14 1,151 3.1 275.1 33.23 4.80 853 2.7 274.7 23.63 4.39 577 2.4 274.4 14.84 4.02 325 2.1 274.1 6.80 2.76 121 1.2 273.2 1.29 0.88 12 0.6 272.6 -0.48 -0.33 -5 0.5 272.5 0.18 0.12 2 0.5 272.5 -0.07 -0.04 -1 0.5 272.5 0.02 0.02 0 0.5 272.5 -0.01 -0.01 0 0.5 272.5 0.00 0.00 0 0.5 272.5 0.00 0.00 0 0.5 272.5 0.00 0.00 0 0.5 272.5 0.00 0.00 0 0.5 272.5 0 00 0 00 0 0.5 272.5 t 1 ~ 1 / ; •< I: • II I; ii 1 t . '. I:-~ -:I ('
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
3 1
32
33
34
35
36
37
38
39
40
4 1
42
43
44
45
Inflow
(cfs)
0 .00
1.26
2.52
3 .78
5.04
6.30
7 .55
8.81
10.07
11.33
12 .59
11.96
11 .33
10.70
10 .07
9.44
8 .81
8 .18
7 .55
6 .92
6.30
5.67
5.04
4.41
3 .78
3.15
2 .52
1.89
1.26
0 .63
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0 .00
0 .00
0.00
0 .00
0 .00
0.00
0 .00
0.00
0.00
Storage Routing Analysis
Detention Pond 1
10-Year Storm Event
11+12
(cfs)
0 .00
1.26
3 .78
6.3 0
8 .81
11 .33
13 .85
16 .37
18 .89
2 1.40
23 .92
24 .55
23 .29
22 .03
20 .77
19 .51
18 .26
17 .00
15 .74
14.48
13 .22
11 .96
10.70
9.44
8 .18
6 .92
5.67
4.41
3 .15
1.89
0 .63
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0 .00
0 .00
o .. od
0 .00
0 .00
0 .00
0 .00
0 00
2s/t-0
0 .00
-0.47
-0.84
0.47
2.80
6 .15
11 .52
18 .74
27.65
38 .59
51 .59
64 .76
76 .27
86 .23
94 .78
101 .94
107 .74
112 .19
115.34
117 .19
117 .77
117 .10
115.21
112 .12
107 .84
102.40
95 .82
88 .12
79 .38
69 .72
59 .17
4 8.36
37 .91
27 .92
18 .77
10 .39
3.48
-0.74
0.27
-0 .10
0.04
-0 .01
0 .01
0 .00
0 .00
0 .00
2s/t+O
0 .00
1.26
3.31
5.45
9 .28
14.13
20.00
27 .88
37 .62
49.06
62.51
76.14
88 .05
98 .31
107 .01
114 .29
120.19
124 .73
127 .93
129.82
130.41
129 .73
127 .81
124.66
120.30
114 .77
108 .07
100 .23
91.27
81 .27
70 .35
59.17
48 .36
37 .91
27 .92
18 .77
10 .39
3.48
-0 .74
0 .2 7
-0 .10
0.0 4
-0 .01
0 .01
0 .00
0 .00
Outflow
{cfs)
0 .00
0 .86
2 .08
2.49
3 .24
3 .99
4 .24
4 .57
4 .98
5.23
5.46
5.69
5 .89
6 .04
6 .11
6 .18
6 .23
6.27
6 .30
6 .31
6 .32
6 .31
6 .30
6 .27
6.23
6 .18
6.12
6.05
5 .94
5.78
5.59
5.40
5 .2 2
5.00
4 .57
4 .19
3.46
2.11
-0 .50
0 .19
-0 .07
0 .03
-0 .01
0.00
0 00
0 00
Storage
if.fl
0
12
37
89
181
304
473
699
979
1,315
1,875
2 , 114
2,465
2 ,768
3 ,027
3 ,243
3,419
3,554
3 ,649
3 ,705
3,723
3,703
3 ,645
3,552
3,422
3 ,258
3,058
2 ,825
2 ,560
2,265
1,943
1,6 13
1,294
988
700
437
208
41
-7
3
-1
0
0
0
0
0
Depth
illl
0 .0
0 .2
0.6
0.8
1.5
2 .0
2.2
2.5
2 .9
3 .2
3.4
3 .6
3 .9
4.0
4.1
4.2
4 .3
4 .3
4 .3
4.4
4.4
4.4
4 .3
4 .3
4 .3
4 .2
4 .1
4 .0
3 .9
3 .7
3 .5
3 .3
3 .1
2 .9
2 .5
2 .2
1.7
0 .9
0 .5
0 .5
0 .5
0 .5
0 .5
0 .5
0 .5
0 .5
Elevation
illl
272.0
272 .2
272 .6
272 .8
273 .5
274 .0
274 .2
274 .5
274 .9
275 .2
275.4
275 .6
275.9
276 .0
276 .1
276 .2
276.3
276 .3
276 .3
276.4
276.4
276.4
276 .3
276.3
276 .3
276 .2
276 .1
276 .0
275 .9
275 .7
275 .5
275.3
275.1
274 .9
274 .5
274 .2
2 73 .7
272 .9
272.5
272 .5
272 .5
272 .5
272 .5
272 .5
272.5
272 .5
Time
(min .)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
3 1
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Inflow
(cfs)
0 .00
1.44
2.88
4.31
5 .75
7 .19
8 .63
10 .07
11.50
12 .94
14 .38
13 .66
12 .94
12 .22
11 .50
10 .79
10 .07
9 .35
8 .63
7 .91
7.19
6.47
5 .75
5 .03
4.3 1
3.60
2 .88
2.16
1.44
0 .72
0.00
0.00
0 .00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 00
Storage Routing Analysis
Detention Pond 1
25-Year Storm Event
11+12
(cfs)
0 .00
1.44
4 .31
7 .19
10 .07
12 .94
15 .82
18.69
21 .57
24.45
27.32
28.04
26.60
25 .17
23.73
22 .29
20 .85
19.41
17 .98
16.54
15 .10
13 .66
12 .22
10 .79
9 .35
7.91
6.47
5 .03
3.60
2.16
0.72
0.00
0 .00
0 .00
0.00
0 .00
0 .00
0 .00
0 .00
0.00
0 .00
0.00
0 00
0 .00
0 .00
0 .00
2s/t-0
0 .00
-0.53
-0 .55
1.19
4.01
8.73
15 .68
24 .68
35 .88
49.48
65.40
81.48
95 .84
108 .53
119 .58
129 .03
136 .91
143 .23
148 .02
151 .32
153 .15
153.53
152.50
150 .07
146.27
141 .12
134.65
126 .88
117 .84
107.54
96.01
83 .98
72 .34
61 .09
50 .21
39 .71
29 .56
20 .28
11 .77
4 .3 2
-0.22
0 .08
-0 .03
0 .01
0 .00
0 .00
2s /t+O --
0.00
1.44
3 .78
6 .64
11.25
16 .95
24.54
34 .37
46 .25
60.32
76.8 0
93.44
108.08
121.00
132.25
141 .87
149.89
156.32
161 .20
164.56
166.42
166.81
165.76
163.28
159.41
154 .18
147 .59
139.69
130.48
120.00
108.26
96.0 1
83.98
72.34
61 .09
50.21
39.71
29.56
20 .28
11.77
4.32
-0 .22
0 .08
-0 .03
0 .01
0 .00
Outflow
(cfs)
0 .00
0 .98
2 .17
2.72
3 .62
4 .11
4.43
4 .85
5 .19
5.42
5 .70
5 .98
6 .12
6 .24
6 .34
6.42
6.49
6 .55
6.59
6.62
6.64
6.64
6.63
6 .61
6.57
6 .53
6.47
6.40
6 .32
6 .23
6.12
6 .0 2
5.82
5 .6 3
5.44
5 .2 5
5 .07
4.64
4.25
3 .72
2 .27
-0 .15
0 .06
-0 .0 2
0 .01
0 .00
Storage
iffl
0
14
48
117
229
385
603
886
1,232
1,647
2,304
2,624
3,059
3,443
3,778
4 ,064
4,302
4,493
4,638
4,738
4,794
4,805
4,774
4,700
4,585
4,429
4,234
3,99 9
3 ,725
3,413
3,064
2 ,700
2,345
2,001
1,669
1,349
1,039
748
481
24 1
61
-2
1
0
0
0
Depth
illl
0 .0
0 .2
0.6
0 .9
1.8
2 .1
2.4
2.8
3 .1
3 .3
3 .6
4 .0
4 .1
4 .3
4.4
4 .5
4 .6
4 .7
4 .7
4 .7
4.8
4 .8
4 .8
4 .7
4 .7
4 .6
4 .6
4 .5
4.4
4 .3
4 .1
4 .0
3 .8
3 .6
3.4
3 .2
3 .0
2 .6
2 .3
1.8
1.0
0 .5
0 .5
0.5
0 .5
0 .5
Elevation
illl
272 .0
272 .2
272.6
272 .9
273 .8
274.1
274.4
274 .8
275 .1
275.3
275 .6
276 .0
276 .1
276 .3
276.4
276 .5
276 .6
276.7
276 .7
276 .7
276 8
276 .8
276 .8
2 76 .7
276 .7
276 .6
276.6
276 .5
276.4
276 .3
276.1
2 76.0
275.8
275 .6
275.4
275 .2
275 .0
274 .6
274 .3
273.8
273 .0
272.5
272.5
272.5
272.5
272 .5
----____________ ____.
I
I
Time
(min.)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Inflow
(cfs)
0.00
1.63
3 .25
4 .88
6 .50
8 .13
9 .75
11 .38
13 .00
14.63
16 .25
15.44
14 .63
13 .81
13 .00
12 .19
11.38
10 .56
9 .75
8 .94
8 .13
7 .31
6 .50
5.69
4 .88
4 .06
3 .25
2.44
1.63
0.81
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0 .00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
Storage Routing Analysis
Detention Pond 1
50-Year Storm Event
11+12
(cfs)
0.00
1.63
4 .88
8 .13
11 .38
14 .63
17 .88
21 .13
24.38
27.63
30 .88
31 .69
30 .06
28.44
26 .81
25.19
23 .56
21 .94
20 .31
18 .69
17 .06
15.44
13.81
12 .19
10.56
8 .94
7 .31
5 .69
4 .06
2.44
0 .81
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
2s/t-O
0.00
-0 .60
-0 .25
1.94
5.40
11 .54
20 .14
31 .06
44 .75
61 .13
80 .09
99.47
116 .91
132.44
146 .11
157 .94
167 .97
176 .23
182.74
187 .54
190 .66
192 .13
191 .98
190 .24
186 .92
182 .07
175.71
167 .87
158 .56
147 .82
135.68
122 .95
110.44
98 .15
86 .08
74 .37
63 .05
52 .11
41 .54
31 .33
21.89
13 .25
5.34
0.40
-0 .15
0 .05
2slt+O
0 .00
1.63
4.27
7.87
13 .32
20 .03
29.42
41 .27
55.44
72 .38
92 .00
111 . 78
129 .53
145.34
159.26
171 .30
181 .51
189 .91
196.54
201.43
204 .60
206 .10
205 .95
204 .17
200 .80
195 .86
189 .39
181.40
171.93
161.00
148 .64
13 5.68
12 2.9 5
110.44
98.15
86 .08
74 .37
63 .05
52.11
41 .54
3 1.33
21.89
13 .25
5.34
0.4 0
-0 .15
Outflow
(cfs)
0 .00
1 .11
2 .26
2 .96
3 .96
4 .24
4 .64
5.10
5 .34
5 .63
5.96
6 .16
6 .31
6.45
6 .57
6 .68
6 .77
6 .84
6 .90
6 .94
6.97
6.98
6 .98
6 .97
6.94
6 .89
6 .84
6 .77
6 .68
6 .59
6.48
6 .37
6 .25
6 .14
6 .04
5 .86
5.66
5.47
5 .29
5.11
4 .72
4 .32
3.9 6
2 .47
0.2 7
-0.10
Storage
.(£1
0
15
60
147
281
474
743
1,085
1,503
2,003
2,760
3 , 169
3,697
4 , 167
4,581
4,939
5,242
5,492
5,689
5,835
5 ,929
5 973
5 ,969
5 ,916
5 ,816
5,669
5,476
5,239
4,957
4 ,632
4 ,265
3,879
3,501
3 ,129
2 ,764
2,407
2 ,061
1,727
1,405
1,093
798
52 7
279
86
4
-1
Depth
illl
0 .0
0.2
0 .7
1.0
2.0
2.2
2 .6
3.0
3 .3
3.6
3 .9
4 .2
4.4
4 .5
4 .7
4 .8
4 .9
5 .0
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.0
4 .9
4 .8
4 .7
4 .6
4.4
4 .3
4 .2
4 .0
3 .8
3 .6
3.4
3 .2
3 .0
2 .7
2 .3
2 .0
1 .1
0 .5
0 .5
Elevation
illl
272 .0
272 .2
272 .7
273 .0
274 .0
274 .2
274 .6
275.0
275.3
275 .6
275.9
276 .2
276.4
276 .5
276 .7
276 .8
276 .9
277 .0
277 .1
277 .1
277 .1
277 .1
277 .1
277 .1
277 .1
277 .1
277 .0
276.9
276.8
276 .7
276 .6
276.4
276 .3
2 76 .2
276 .0
275 .8
275 .6
275.4
275 .2
275 .0
274 .7
2 74 .3
2 74 .0
2 73 .1
2 72 .5
272 .5
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
2 1
22
23
24
25
26
2 7
28
29
30
3 1
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Inflow
(cfs)
0 .00
1.70
3 .39
5.09
6 .79
8.49
10 .18
11 .88
13 .58
15 .27
16 .97
16 .12
15 .27
14.42
13 .58
12 .73
11 .88
11 .03
10 .18
9 .33
8.49
7.64
6.79
5 .94
5 .09
4 .24
3 .39
2 .55
1.70
0.85
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0 .00
0 .00
0.00
0 .00
0 .00
0 .00
Storage Routing Analysis
Detention Pond 1
100-Year Storm Event
11+12
(cfs)
0 .00
1.70
5 .09
8.49
11 .88
15 .27
18 .67
22 .06
25.46
28 .85
32 .24
33 .09
31 .39
29 .70
28 .00
26 .30
24 .61
22.91
21.21
19 .52
17 .82
16 .12
14.42
12 .73
11 .03
9.33
7 .64
5 .94
4 .24
2 .55
0 .85
0 .00
0 .00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
2s/t-O
0 .00
-0 .63
-0 .14
2 .23
6 .13
12 .80
22 .02
33 .78
48.43
65 .86
86 .03
106.68
125.30
141 .93
156 .60
169 .34
179.38
186.53
191 .21
193 .76
194.49
193 .67
191 .50
188 .19
183 .90
178 .77
172 .79
165 .24
156 .16
145 .57
133 .50
120 .81
108 .34
96 .09
84 .05
72.41
61.15
50 .28
39.77
29 .62
20 .33
11 .8 2
4 .35
-0.2 1
0 .08
-0 03
2s/t+O
0.00
1.70
4.46
8 .35
14 .11
21.40
31.47
44.08
59 .24
77 .27
98 .10
119 .12
138 .08
155.00
169 .93
182 .90
193 .95
202.29
207.75
210 .72
211.58
210.61
208.09
204.23
199.22
193.24
186.41
178 .73
169.48
158 .70
146.42
133 .50
120 .81
108 .34
96 .09
84 .05
72.41
61 .15
50 .28
39 .77
29 .62
20 .33
11 82
4 .35
-0 .2 1
0 .08
Outflow
(cfs)
0 .00
1.16
2 .30
3 .06
3 .99
4 .30
4 .72
5.15
5 .41
5.71
6 .04
6 .22
6 .39
6 .53
6 .67
6 .78
7 .28
7 .88
8 .27
8.48
8 .54
8.47
8 .29
8 .02
7 .66
7 .23
6 .81
6 .74
6 .66
6 .57
6 .46
6.35
6 .23
6.13
6.02
5.82
5 .63
5.44
5 .25
5.07
4.65
4 .25
3.73
2 .28
-0 .14
0 .05
Storage
i£fl
0
16
65
159
304
513
802
1, 168
1,615
2, 147
2 ,943
3 ,387
3,951
4,454
4,898
5,284
5,600
5,832
5,984
6,067
6 091
6,064
5,994
5,886
5,747
5,580
5,388
5 , 160
4,885
4,564
4 ,199
3 ,815
3,437
3 ,066
2,702
2,347
2,003
1,672
1,351
1,041
749
482
243
62
-2
Depth
illl
0 .0
0 .2
0.7
1.0
2 .0
2 .3
2 .7
3.1
3 .3
3.7
4 .0
4 .2
4.4
4 .6
4 .8
5 .0
5.1
5.1
5.1
5 .2
5 .2
5.2
5 .2
5.1
5.1
5.1
5.0
4.9
4 .8
4.7
4 .5
4 .4
4 .3
4.1
4.0
3.8
3 .6
3 .4
3 .2
3.0
2.6
2 .3
1.9
1.0
0 .5
0 .5
Elevation
illl
272 .0
272 .2
272 .7
273 .0
274.0
274 .3
274 .7
275 .1
275.3
275 .7
276 .0
276.2
276.4
276 .6
276 .8
277 .0
277 .1
277 .1
277 .1
277 .2
277.2
277 .2
277 .2
277 .1
277 .1
277 .1
277 .0
276 .9
276 .8
276 .7
276.5
276.4
276 .3
276 .1
276.0
275 .8
275 .6
275.4
2 75 .2
2 75 .0
2 74 .6
27 4 .3
273.9
273 .0
272 .5
272 .5
I
I
I
EXHIBIT A
Pre-Development Drainage Area Map
-~I l
·-
"
' .
,
"' ' . '·
J.f. , '(
Draina ge Report
for
The Glade Subdi vision, Section 12
College Station, Tex as
July 20 0 5
R ev i-sed July 2 005
Deve loper:
7 B Investments , Ltd.
1305 West Villa Maria
Bryan , Texas 7780 l
(979) 779-9375
Prepared B v :
TEX ON General ontractors
1707 Graham Road
oll ge tation Te as 778 45
(979) 764-7743
. ~
r
CERTIFICATlON
I, Joseph P. Schultz, Licensed Professional En g in eer No. 65889, State of Texas , ce rtify that
this revis ed re port for the drainage d es ign for Th e Glade Subdivisio11 , Sectio11 12, was
prepared by m e in acco rdanc e with th e provisions of the City of Co ll ege Station Drainage
Policy and Design Standards for the owners h ereof.
TABLE OF CONTENTS
DRAINAGE REPORT -REVISED 712005
THE GLADE SUBDlVISlON, SECTION 12
CERTIFICATlON .................................................................................................................................................................. 1
TABLE OF CONTENTS ........................................................................................................................................................ 2
LIST OF TABLES .................................................................................................................................................................. 2
INTRODUCTION ................................................................................................................................................................... 3
GENERAL LOCATION AND DESCRIPTION .................................................................................................................. 3
FLOOD HAZARD INFORMATION .................................................................................................................................... 3
DEVELOPMENT DRAINAGE PATTERNS ....................................................................................................................... 3
DRAINAGE DESIGN CRITERIA ........................................................................................................................................ 3
STORM WATER RUNOFF DETERMINATION .............................................................................................................. .4
DETENTION FACILITY DESIGN ..................................................................................................................................... .4
STORM SE\VER DESIGN .................................................................................................................................................... 6
CONCLUSIONS ..................................................................................................................................................................... 6
APPENDIX A .......................................................................................................................................................................... 7
Storm Sewer [II/et Design Calculatio11s
APPENDIX B ........................................................................................................................................................................ 10
Storm S e wer Pipe Design Calculations
APPENDIX C ........................................................................................................................................................................ 15
Figure 1 -Required Detention Storage,
Pond Area-Capacity Data, Depth-Discharge Data & Storage Routing Aualysis Parameters
APPENDIX D ........................................................................................................................................................................ 19
Storage Routing Aualysis -Detention Pond
EXHIBIT A ............................................................................................................................................................................ 30
Pre-D e velopment Drninage Area Map
EXHIBIT B ............................................................................................................................................................................ 32
Po st-D evelop111e11t Drni11age Area Map
LIST OF TABLES
TABLE l -Rain fa ll Intensity Calculation s ....................................................................................... 4
TAB LE 2 -Pre-& Post-D eve lopm ent Runoff Infornrntion ............................................................ 4
TAB LE 3 -Pre-& Pos t-D eve lopm ent Pea k Di sc ha rge Co mparison -De te nti o n Po nd Desig n ...... 5
TAB LE 4 -Summ ary o f Max imum Po nd Water Le ve ls .................................................................. 5
INTRODUCTlON
DRAlNAGE REPORT -RE VISED 712 005
THE GLADE SUBDIVlSION, SECTION 12
T h e purp ose of this revised re port is to provide th e hydrolo g ical effects of the construct ion
of Tlte Glade Subdivision, Section 12 , and to verify that th e proposed s torm draina ge
system m eets the requirements set forth by th e City of Co ll ege S tat ion Drainage Po lic y a nd
Design Standards .
GENERAL LOCATION AND DESCRIPTION
The proj ec t is locat ed on a 3 acre tract locate d on Southwest Parkway notih of the
Southwood Drive intersection in College Station, Texas. The site is predominantly open
with a few trees . The existing gro und e levation s range from E levation 278 to Elevation
286 . The general location of the proj ect s it e is shown on th e vic init y map in Exhibit A .
FLOOD HAZARD INFORMATION
The proj ect si t e is located in the B ee Creek Drainage Basin. The site is located in a Zo n e X
Area according to the Flood Insurance R ate Map prepared b y the Federal Emergency
Management Agency (FEMA) for Brazos Co unty, Texas and incorporated areas dated July
2, 1992 , panel number 48041C0144-C. Zon e X Areas are detennined to be outsid e th e
500-year floodplain.
DEVELOPMENT DRAINAGE PATTERNS
Prior to development, the storm water runoff flo ws to the east into the Southwest Parkway
right-of-way or into an existing concrete drainage flume, which discharges into the
Southwest Parkway right-of-way. The runoff flo wing into the street enters the ex isting
inlets and storm sewer system. Ultimately, this nmoff flows into Bee Creek.
DRAINAGE DESIGN CRITERIA
T he desi gn parameters for th e sto1111 sewer and detent io n facility a na lys is are as fo ll ows:
• The R a tional Method is utili zed to d e te1111ine p eak stom1 water run off rat es fo r th e
stonn sewer d esign a nd th e detention fac ilit y design.
• D es ig n Storm Frequency
Stonn sewer sys te m
Detention facility a n a lysis
• Runoff C oefficients
Pre-developm e nt
10 and 100-year sto m1 events
5 , 10 , 25, 50 and 100-yea r stom1 event s
Post-deve lopment (s in g le fa mil y res id e nti a l)
c = 0.40
C = O.C>O
• Ra in fa ll lnt e ns it y e quation s a nd va lu es for Br azos Co unt y ca n be fo und in Tab le I .
• Tim e of Co ncentrat io n , le -Due to the s m a ll dra in age a reas, a minimum le o f' I 0
minut e s is use d to dete rm in e th e rain fa ll int e ns it y va lu es.
STORM WATER RUNOFF DETERMIN AT ION
The peak runoff va lu es were determin ed in accordance with th e criteria present e d in the
previous section for th e 5, l 0, 25, 50, and I 00-year storm events . The drainage areas for
the pre-& post-development conditions for the d e tention pond ana lysis are s h own on
Exhi bits A & B , respective ly . The drainage areas for the post-deve lopment conditions for
the stom1 sewer design are shown on Exhibit B . Pre-a nd post-development runoff
condit ion s a re summarized in Tab le 2. Du e to th e sma ll si ze of the drainage areas for thi s
site, a time of concentration of 10 minutes has been used for a ll of the drainage areas .
TABLE 1 -Rainfall Intensity Calculations
Rainfall Intensity Values {in/hr)
Storm l e=
Event 10 min
Is 7 .693
110 8.635
'2s 9 .8 61
lso 11.148
1100 11.639
Brazos County:
5 '{ear storm 10 '{ear storm
b= 76 b= 80
d= 8.5 d= 8 .5
e= 0 .785 e= 0 .763
I = b I {tc+d)e
I = Rainfall Intensity {in/hr)
tc = L/{V*60)
le = Time of concentratio n {min)
L = Length (ft)
V = Velocity (ft/sec)
25 '{ear storm 50 '{ear storm 100 '{ear storm
b= 89 b= 98 b= 96
d= 8 .5 d = 8 .5 d= 8 .0
e= 0.754 e= 0 .745 e= 0 .730
(Data taken from State Department of Hiqhwa'f.S and Public Transportation H'{drau/ic Manual, page 2-16)
TABLE 2 -Pre-& Post-Development Runoff Information
Area 5 year storm 10 year storm 25 year storm 50 year storm 100 year storm c le Area# (acres) Is Os 110 0 10 125 0 2s l so O so
A (min) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs)
Pre-Development Drainage Area
101 3.00 0.40 10 7.693 923 8 .635 10 .36 9 .861 11 .83 11 .148 13 .38
Post-Development Drainage Areas
20 1 1.14 0 .60 10 7 .693 5.26 8 .635 5 .91 9.861 6 .75 11 .148 7 .62
202 0 .79 0 .60 10 7 .693 3 .65 8 .635 4.09 9 .861 4 .67 11 .148 5.28 -----
203 0 .50 0.60 10 7 .693 2.31 8.635 2 .59 9 .861 2 .96 11 .148 3 .34 ---------
204 0 .57 0 .60 10 7 .693 2 .6 3 8 .635 2.95 9 .86 1 3 .37 11 .14 8 3 .81
201 & 202 1.93 0 .60 10 7 .693 8 .91 8 .635 10.00 9 .86 1 11.42 11 .14 8 12 .91 --
20 1,2 02 ,203 2.43 0 .60 10 7 .693 11 .22 8 .635 12 .59 9 .861 14 .38 11 .148 16.25
DETENTION FACILITY DESIGN
Due to the in c rease in th e peak run off du e lo this deve lopment , a detention facility is
n eede d for the runoff th at no ws int o th e So uthw e s t Pa rkwa y right-of-way .
1100 0100
(in/hr) (cfs)
11 .639 13 .97
11 .639 7.96
11 .639 5.52 -----
11 .639 3.49 ----
11 .639 3.98 ----
11 .639 13.48 ----
11 .639 16 .97
T he d es ign s to rm fo r th e d e te nti o n fac ilit y is th e I 00-yea r s to rm eve nt. T h e d e ten ti o n pond
is locat e d in th e no rth e a s t co m e r of th e tr ac t a dj ace nt to S o uth wes t Pa rkway . T h e p eak
ru noff va lu es we re d e te rmin ed in acco rda nce w ith th e c rit e ri a p rese nt ed in previo us
sect io ns fo r the 5, I 0, 25, 50 & I 00 -year s to rm even ts for p re-deve lo pm e nt condit io ns.
Tabl e 2 s hows a s umm a ry of th ese res ult s . Th e p os t-d eve lopm e nt peak runo ff va lu es a re
a ls o s umm a ri zed in T a bl e 2. Fi g ur e 1 in A pp e ndi x C s ho ws th e required d e te nti o n s to rage
vo lum e for the p o nd fo r th e I 0 0 -yea r s to rn1 even t.
TABLE 3 -Pre-& Post-Development Peak Discharge Comparison -Detention Pond Design
Item Location O s 010 0 2s O so
(cfs) (cfs) (cfs) (cfs)
Pre -Development
A To ta l Dis charge From Site (Area 101) 9 .23 10 .36 11 .83 13 .38
Post-Development without a Detention Pond
B To tal Discharge From Site (Areas 201 -2 04) 13 .85 15 .54 17 .75 20 .05
Post-Development with Pond
C1 Into Pond (Areas 201 -203 ) 11.22 12.59 14 .38 16.25
C2 Out of Pond (Appendi x D) 6 .09 6.32 6.64 6 .9 8
C3 Di s ch a rge Into Southwes t Pkwy · Area 204 2 .63 2.95 3 .37 3.8 1
C4 Di scharge Into Southwest Pkwy -Inl et 2 Bypa ss 0 .00 0 .00 0 .16 0 .8 7
c Total Po s t-Development Discharge From Site (C 2+C3+C4) 8.72 9.27 10.17 11 .66
D Decrease in Runoff From Pre-Development (A-C) 0 .51 1.09 1.66 1.72
T h e pond o utl e t s tructure is a concre te ri ser structure which is 3.5 'x3 .5' in s ize, 4 .0' hi g h ,
a nd with a 2.5 'x 2.5 ' ope ning a t its top. T h e re is an 12" hi g h b y 8" wid e op e ning in th e
front fac e of the structure with its invert a t E lev ation 2 72 .0 to control th e flow . T h e
di s charge pipe is an 18" reinforced concrete pipe, 28 fe et in le n g th , which di s char ges into a
junction box to be constructed on an e xisting 30" s to rm sewer pipe. The pipe h as a d esi gn
slope of 1.0%. The top of the pond berm is at Elevation 278 .0. There is a 5 ' o verflow
spillway on the top of the berm with a flo w line elevation of 277.5 .
A s shown in T a bl e 3 , the peak outflows from the d e te ntion fa ciliti e s ar e le s s th a n the
a llow a bl e peak outflow for the d e si gn storm e vent. A dditiona ll y, T a bl e 4 presents th e
max imum wate r s urface in th e pond s for th e 10 0 -year s torm event , as we ll as th e a m o un t
of free board prov id ed.
TABLE 4 -Summary of Maximum Pond Water Levels
Location 0 100 Max . Water Surface Top of Berm Freeboard , ft.
(cfs) Elevation, ft . Elevation, ft .
Pond 8 .54 277.2 278 .0 0.8
T h e a rea-capac it y d a ta , the d e pth-di sc harge d at a a nd the Storage R o uti ng A na lys is
Pa ram e ters fo r th e propo sed d e te nti o n p o nd is p rovided in Appendi x C. O nl y 90% o f th e
des ig n vo lum e was used fo r th e S torage R o utin g Ana lys is.
T h e peak now o ut of th e d e te nti o n fac ili ty was determin e d by a S to rage Ro utin g A n a lys is
bas ed o n th e Co ntinui t y Equ a ti o n a s fo ll ows: (I I +12)+((2s I /d t )-0 I )=((2 s 2/d t)+02). T he
time int erva l, ci t, used was I min ute. T he ca lc ul ation s a nd res ult s of the S to ra ge Ro utin g
.'\nal ys is arc pro' id c d in /\p p c ndi \ fJ
0100
(cfs)
13.97
20.95
16.97
8 .54
3.98
1.14
13.66
0.31
A 3 ' vvid e co ncre te low flow flum e is prop osed to carr y the fl ow in th e detention pond to
th e pond o utlet structure . Block so d grass wi ll b e plac e d in th e d e te ntion po nd to co ntrol
eros ion .
STORM SEWER DESIGN
The storm sewer piping for this project has been se lecte d to b e Reinforced Concrete Pip e
(RCP) meet ing the requirements of ASTM C-76 , C la ss [([ pipe meeting the requirem e nts
of ASTM C -789 . The curb inlets wi ll be cast-in-place concrete.
Append ix A presents a summary of the storm sewer inl et desi g n parameters and
calculations. The inlets were designed based on a I 0-year desi g n storn1 .
Inlets for the residential streets were locat ed to maintain a gutter flow depth of 5" or less .
This design depth will prevent the spread of water from reaching the crown of the road for
the l 0-year storm event. Refer to Appendix A for a summary of the gutter flo w depths .
The runoff intercepted by the proposed storm sewer inlets was calcu lated using the
following equations. The depth of flow in the gutter was detem1ined by using the Strai g ht
Crown Flow equation. The flow intercepted by Inlets 1 & 2 was calculated by using the
Capacity of Inlets On Grade equation. These equations and resulting data are summarized
in Appendix A. There are no Inlets In Sump for this project. The area between the right-
of-way and the curb line of the streets will be graded as necessary to provide a minimum of
6" of freeboard above the curb line. This w ill ensure that the runoff from the 100-year
sto rm event will remain within the street right-of-way.
Appendi x B presents a summary of the storm sewer pipe design parameters and
calculations. All pipes are 18" in diameter or larger. For pipes with 18" and 24"
diameters, the cross-sectional area is reduced by 25 %, as per Co llege Station requirements.
A summary of how this was achieved is shown in Appendix B as well. The pipes for the
storm sewer system were designed based on the 10-year storm event, and they will also
pass the 100-year storm event. Based on the depth of flow in the street determined for the
100-year stom1 event, this runoff will be co ntain ed within the street right-of-way until it
enters th e storm sewer system . As required by College Station, the velocit y of flow in th e
s tom1 sewer pipe system is not low e r than 2.5 feet per second , and it do es not exceed 15
fee t p e r second. As the data shows , even during low flow conditions, th e velocity in th e
pipes will exceed 2.5 feet per second and prevent sed iment build-up in the pip es. The
maximum flow in the stom1 sewer pipe system will occ ur in Pipe No . 2. The m ax imum
ve locity for the pipe system in this development will be 6 .5 feet per second and will occur
in Pipe No . 2. Appendix B contains a summary of th e pip e calculations.
CONCLUSIONS
T he co ns truction of this proj ect will increase th e sto rm wat e r runoff from thi s s it e . The
proposed sto rm sewer system s hould adequate I y co ll ec t a po rtion of th e runoff a nd re lease
it into th e d e tention pond . T h e in c reased runoff h as bee n red uced b y th e prop osed
de te ntion fac ilit y, and there s hould be no flood d a m age to downstream o r a dj acent
landow ne rs res u I tin g from thi s cl eve lopme n t.
I
I
APPENDIX A
Storm Sewer Inlet Design Calculations
I
The Glade Subdivision
Depth of Flow in Street Gutter
Revised 712005
Gutter A c Location (ac res)
A1 1.14 0 .6 -
A2 0 .79 0 .6
Transve rs e (C rown) slope (fl/ft)
for 27' str eet= 0 .03 30
Slope
(ft/ft)
0 .0110 --
0 .0 11 0
10-year storm
0 10 Y1 0-actual
(cfs) (ft) (in)
5 .91 0 .34 8 4 .17
4 .09 0 .30 3 3 .64
Straight Crown Flow (Solved to find actual depth of flow in gutter, y):
Q = 0 .56 * (z/n) * S112 * y813 ¢ y ={QI (0.56 * (z/n) * S112]}318
n = Roughness Coefficient = 0 .018
S = StreeUGutter Slope (fl/ft)
y = Depth of flow at in let (ft)
z = Re c iprocal of c rown slope :
for 2 7' street = 30
100 -year storm
0 100 Y100
(cfs) (ft) (in)
7 .96 0 .389 4 .67
5 .52 0 .339 4 .07
Tl1e Glade S ubdiv isi o n
!nl et Length Calculati o ns
1?ev ised 712 0 05
Inlets On Grade 10 yea r storm
Flow from Y10 O pw 1001 Oc..,.c::11 Q bypus O u,ptvrec1 inle t rt Length
1
2
10'
10'
Ar ea # (ft) I (in)
202 ___<'.:303 _~ ·• --201 0.348 4. 17
Transver se !Crown) slope !fVftl
for 27' street = 0 .033
(ft) (els ) (els )
0.60 5.97 -1 .88
0.64 6.41 -0.50
St rai ght Crown Flow !So lved to find ac tual depth of flow, yl:
a = o.s6 • (z/n) • s112
• y'" ¢ y = {Q / [0 .56 • (z/n) • s112n'"
n = Roughness Coefficient = 0 .018
S = St reeVGutter Slope (ft/ft)
y = Depth of flow at inle t (ft)
Capaci t y of Inlet s o n grad e:
Oc = 0.7' [1/(H , -H2))' [H ,512 -H2
512 ]
Oc = Fl ow capacity of inlet (c fs )
H 1 =a+ y
H2 =a= gutter depression (2" Standa rd : 4" Recessed )
y = Depth of flow in approach gutter (ft)
(els)
4.09
5.91
a,..,.,_ O byp-tot• O upt-totl 0 10-Tot .. Y100
(els) jfrom lnl•t # (els) (efs) (els) (ft) I (In)
I 0.00 4.09 4.09 o.339 I 4.07 -I 0.00 5.91 5.91 o.3 89 I 4.67
z = Reciprocal of crown slope
for 27' street = 30
Inlets In sumps, Weir Fl ow :
L = QI (3 • y 312) ¢ y = (QI 3L)213
L = Lengt h of inlet openi ng (ft)
a = Flow at inlet (e l s)
y = total depth of flow on inlet (ft)
max y fo r inlet in su m p = 7" = 0 .583'
100 year sto rm
O per1oot O c..,.c11y a.,. •• O c..,1ur«1 O urry0¥ef a byp.tot• O upt.tolt 0 100.Tot• s L ..::1ua1
(ft) (els) (els) (els ) (els ) j from lnMtt (els) (els ) (els) (ft/ft) (ft )
0.63 6.32 -0 .80 5.52 I 0.00 5.52 5.52 0.01 10 10 --------~ ---
0.68 6.82 1.14 6.82 1. 14 7.96 0.0110 10
I
I
I
APPENDIX B
Storm Sewer Pipe Design Calculations
iii
I
I
T he Glade Subdivision
P i pe Calculations
.R.evise d 712005
Inlet Outlet 10 y ear sto rm 100 year sto rm
Pi pe# Size Length Slope
Invert Elev Invert Elev *Actual Flow Design Flow V10 Travel Time , tno *Actual Flow Design Flow V100 % Full
(in) (ft) (%) (ft) (ft) (cfs) (cfs) (fps) (sec) (min) (cfs) (cfs) (fps)
2 24 102 .9 0 .80 274.58 273 .76 10.00 16.15 6 .7 71.4 15 0.26 12.34 19.93 6 .7 ----------
3 18 31 .0 1 .20 275 .39 275 .02 5 .91 9 .54 6 .8 73 .7 5 0.08 6 .82 11 .01 6 .9
·The se values refl ect the actual flow for the 18" & 24" pipes . The design flow for these pipe sizes reflects a 25 % reduction in pipe area .
t Re fe r to attached calculation for specific information .)
% Full
89 .0 ---
85.0
Travel Ti me , tn 00
(sec) (min)
15 0 .26
-
4 0.07
I
City of College Stati on requirement t o Reduce Cro ss-Secti on a l A rea of 18 " & 24" Pi p e s by 25%
Using Mannings Equ atio n fr o m pag e 48 of th e College Station Drainag e Policy & Design Standards Manual :
Q = 1.49 fn *A * R213 * S112
Q = Flow Capacity (cfs)
18" Pi p e:
Pipe size (inches) = 18
Wetted Perimeter W P, (ft)= 4 .7 1
C ross -Se c tional Area A , (ft2 ) = 1 .766
Reduced Area A R, (ft2 ) = 1 .325
Hydraulic Radius R =A/WP, (ft)= 0 .375
Reduced Hydr Rad iu s RR = A R/Wp , (ft)= 0.28 1
Rough ness Coefficient n = 0 .014
Friction Slope of Conduit Sr . (fUft) = 0 .0 1
Example Calcu lation:
S lope Flow Capacity Red uced Flow Capacity % Differe nce
s Q Q reduced Ored uceiQ
0.005 6.91 4 .28 0.619
0.006 7.57 4 .69 0.619
0 .007 8.18 5.06 0.619
24" P i p e :
Pipe size (inches) = 24
Wetted Perimeter WP, (ft)= 6 .28
Cross-S ectional Area A , (tt2) = 3 .14
Red u ced Area AR, (W) = 2 .355
Hyd ra u lic Ra diu s R =A/W P, (ft)= 0 .5
Reduced Hydr Radius RR= A R/Wp , (ft)= 0 .3 7 5
Roughness Coefficient n = 0 .014
Friction Slope of Conduit Sr. (fUft) = 0 .01
Exa mple Calcu lation:
Slope Flow Capacity Reduced Fl ow Capac it y % Difference
s Q Oreduced O reducei Q
0 .005 14 .8 9 9 .22 0.619 ---------
0 .006 16 .31 10 .1 0.619 -----·---
0 .007 17 .61 10 .9 0.619
Con c l usion:
Multiply actual Q in 18" & 24" pip es by 1.61 5 to reflect a 25% reduction in th e
cross-sectio nal area called for on page 4 7 , paragraph 5 o f the College Sta ti o n
Drai nage Policy & D esign Standards manual.
I
Pipe 2 -10 Year Storm
Manning Pipe Calculator
Give n Input Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results:
Depth .......................... .
Area ........................... .
Wetted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hy draulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full flow velocity ............. .
Circular
Depth of Flow
2 4.0000 in
16.1500 cfs
0.0080 ft/ft
0.0140
17 .1467 in
3.1416 ft2
2.4015 ft2
48 .33 75 in
75.3982 in
6.7250 fps
7.1542 in
71 .4446 %
18.7888 cfs
5.9807 fps
Pipe 2 -100 Year Storm
Manning Pipe Calculator
Given Input Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning' s n .................... .
Computed Results:
Dept h .......................... .
Area ........................... .
We tted Area .................... .
Wette d Perimeter ............... .
Perimeter ...................... .
Veloci t y ....................... .
Hy draulic Radius ............... .
Pe rcent Full ................... .
Full flow Flowrate ............. .
Full flow ve locity ............. .
Th e Glad e Subdi vi si o n
C o llPq( c::L,<t.i ci•1. Tc-:-:1~··
!~'e \.. j. :r
Circular
Depth of Flow
24 .0000 in
19.9300 cfs
0.0080 ft/ft
0 .0140
21.3713 in
3 .1 416 ft2
2.9547 ft2
59.2072 in
75.398 2 in
6.7451 fps
7 .18 63 in
89 .0 471 %
18 .78 88 cfs
5.9807 fps
I
Pipe 3 -1 0 Year S t o rm
Ma nn ing Pipe Calculato r
Gi ven I nput Data:
Shape ........................ .
Solv ing f o r .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results :
Depth .......................... .
Area ........................... .
Wetted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full flow ve locity ............. .
Circular
Depth of Flow
18 .0000 in
9.5400 cfs
0.0120 ft/ft
0 .0140
13. 2613 in
1.76 71 ft2
1.3956 ft2
37.1527 in
56.5487 in
6.8357 fps
5.4092 in
73 .6 741 %
10 .6 850 cfs
6.0465 fps
Pipe 3 -100 Year Storm
Manning Pipe Calculator
Given Input Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results:
Depth .......................... .
Area .......................... · ·
Wetted Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Full flow Flowrate ............. .
Full fl ow veloci t y ............. .
T h e Glade Subdi visio n
Co1 lec:1e Sl.i:>t i ci •1, Tr·-:·:·1!:
Circular
Depth of Flow
18.0000 in
11.0100 cfs
0.0120 ft/ft
0 . 0140
15 .2995 in
1 .7671 ft2
1 .6009 ft2
42 .2301 in
56.5487 in
6.8774 fps
5 .4588 ill
84.9973 %
10.6850 cfs
6.0465 fps
APPENDIX C
Figure 1 -Required Detention Storage,
Pond Area-Capacity Data, Depth-Discharge Data & Storage Routing Analysis Parameters
I
I '
The Glade Subdivision
Figure 1 -Required Detention Storage
25 -----------~----------~
20
15
Vi' -~
a
~-
0 u::
.>e.
<a
QI
Q.
10
5
I 10 20 30
T ime of Concentration, l e (min)
The Glade Subdivision
Detention Pond Area-Capacity & Depth-Discharge Data
Revised 712005
V = H * {[A1+A2 + (A1*A2)112] / 3}
V = vo lum e, ft 2
A= area , ft 2
H = difference in elevation ft
DETENTION POND
Area • Capacity Data
Elevation Depth Area Volume Cumulative 90 %
Volume Cumulative
(ft) (ft) (ft2) (ft3) (ft3) (ft3)
272 0 0 0 .00 0 .00 0 .00 ----------
273 .00 1.00 92.06 30 .69 30 .69 27 .62 ---------------·------
274 .00 1.00 496.52 267.46 298.15 268 .33 ----------·-· ----------·
275.00 2.00 -~?9Q .~1 862.46 11 60 .60 1044 .54 ----------------
276.00 3.00 2,391 .85 1813 .03 2973 .64 2676 .27 ----··---------
277.00 4.00 3,755 .52 3048 .16 6021.79 5419 .62 --------
278 .00 5.00 5 ,195 .97 4456 .30 10478 .10 9430.29
DETENTION POND
Depth -Discharge Data
Elevation 8" Weir 8"x12" Orifice Opening 18" RCP Max Flow from Outlet
Depth Flow Depth Flow
(ft) (ft) (cfs) (ft) (cfs)
272 .00 0 0 0 0 -------·--- ------
273 .00 1.0 2 0.5 2 .28 ---------------------
274.00 --1.5 3.9 4 ---- --
275 .00 --2.5 5.08 -------------------
276 .00 --3.5 ---------------
277.00 ---
278 .00 --
Weir Flow Equation : Q = 3.0 • L • y3'2
Orifice Flow Equation : Q = 4 .82 •A• y112
4.5
-
6 .01 -----
6.82
-
Depth Flow Structure
(ft) (cfs) (cfsl
0 0 0 ------
--2 .00 -------3.94 ----------
--5 .08 -------------
--6.01
-----------
--6.82 ------
6 .0 19 .80 19 .80
Note : When the depth in the pond exceeds Elevation 277 .0 , the 18" outlet pipe becomes
the flow control structure for the pond.
I
The Glade Subdivision
Storage Routing Analysis Parameters
Revised 712005
t=60s
Detention Pond No . 1
Elevation Depth Discharge Storage
(ft) (ft) (Q , cfs) (s , cf)
272.00 0.00 0 .00 0 .00 ---
273 .00 0 .00 2.00 27 .62 - -
---
274 .0 0 1.00 3 .94 268.33 -----
275 .00 2.00 5 .08 1,044.54 -----
276 .0 0 4 .00 6 .01 ~,_6?~.27 ---- -
277 .00 5 .00 6 .82 _5,41~:62 ---------------
278.00 6 .00 19 .80 10,478 .10
18" Outl et Pipe
3 .5'x3 .5' Concrete Riser wi 12" high x 8" wide opening
Opening flowline Elev . = 272.0
Top Elev . = 277 .0
2 sit
0 .00
0 .92
8 .94
34 .82
89 .21
180 .65 -----· 349 .27
2 sit+ 0
0 .00
2.92 ---
12 .88 ----·--39 .90
95.22 ----187.47 -·--369.07
I
I
APPENDIXD
Storage Routing Analysis -Detention Pond
Time (min.) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 Inflow (cfs) 0.00 1.12 2.24 3.37 4.49 5.61 6.73 7.85 8.98 10.10 11.22 10.66 10.10 9.54 8.98 8.42 7.85 7.29 6.73 6.17 5.61 5.05 4.49 3.93 3.37 2.81 2.24 1.68 1.12 0.56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 00 0 00 0 00 0.00 0 00 Storage Routing Analysis Detention Pond 1 5-Year Storm Event 11+12 (cfs) 0.00 1.12 3.37 5.61 7.85 10.10 12.34 14.59 16.83 19.07 21.32 21.88 20.76 19.64 18.51 17.39 16.27 15.15 14.03 12.90 11.78 10.66 9.54 8.42 7.29 6.17 5.05 3.93 2.81 1.68 0.56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 00 0.00 0.00 0.00 2s/t-0 0.00 -0.41 -1.09 -0.10 1.87 4.44 8.57 14.41 21.81 30.69 41.45 52.38 61.86 69.93 76.65 82.06 86.26 89.28 91.14 91.87 91.48 90.00 87.44 83.82 79.23 73.72 67.30 60.01 51.89 42.95 33.23 23.63 14.84 6.80 1.29 -0.48 0.18 -0.07 0.02 -0.01 0.00 0.00 0.00 0.00 0.00 0.00 2s/t+O 0.00 1.12 2.95 4.52 7.75 11.97 16.78 23.16 31.24 40.89 52.01 63.32 73.13 81.49 88.45 94.04 98.33 101.41 103.30 104.04 103.65 102.14 99.54 95.85 91.12 85.41 78.76 71.22 62.82 53.57 43.51 33.23 23.63 14.84 6.80 1.29 -0.48 0.18 -0.07 0.02 -0 01 0.00 0.00 0.00 0.00 0.00 Outflow (cfs) 0.00 0.77 2.02 2.31 2.94 3.76 4.10 4.37 4.71 5.10 5.28 5.47 5.64 5.78 5.90 5.99 6.04 6.06 6.08 6.09 6.08 6.07 6.05 6.02 5.94 5.85 5.73 5.61 5.47 5.31 5.14 4.80 4.39 4.02 2.76 0.88 -0.33 0.12 -0.04 0.02 -0.01 0.00 0.00 0.00 0.00 0.00 ! ~ 1 ~-I ' ; ' { t: ; 1 I ! ; d t t ''. I'-' • I· ' Storage .lf.!l 0 11 28 66 144 246 380 564 796 1,074 1,560 1,736 2,025 2,271 2,476 2,642 2,769 2,860 2,917 2,939 2,927 2,882 2,805 2,695 2,555 2,387 2, 191 1,969 1,721 1,448 1, 151 853 577 325 121 12 -5 2 -1 0 0 0 0 0 0 0 Depth .illl 0.0 0.1 0.6 0.7 1.0 1.9 2.1 2.4 2.7 3.0 3.2 3.4 3.6 3.7 3.9 4.0 4.0 4.1 4.1 4.1 4.1 4.1 4.0 4.0 3.9 3.8 3.7 3.5 3.4 3.2 3.1 2.7 2.4 2.1 1.2 0.6 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Elevation .illl 272.0 272.1 272.6 272.7 273.0 273.9 274.1 274.4 274.7 275.0 275.2 275.4 275.6 275.7 275.9 276.0 276.0 276.1 276.1 276.1 276.1 276.1 276.0 276.0 275.9 275.8 275.7 275.5 275.4 275.2 275.1 274.7 274.4 274.1 273.2 272.6 272.5 272.5 272.5 272.5 272.5 272.5 272.5 272.5 272.5 272.5
I
Time
(min .)
0
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
4 3
44
45
Inflow
(cfs)
0 .00
1 .26
2.52
3 .78
5 .04
6 .30
7 .55
8 .81
10.07
11.33
12 .59
11 .96
11 .33
10 .70
10 .07
9.44
8 .81
8 .18
7 .55
6 .92
6.30
5 .67
5 .04
4.41
3.78
3 .15
2 .52
1.89
1 .26
0 .63
0.00
0.00
0 .00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0.00
0 .00
0 .00
0 .00
Storage Routing Analysis
Detention Pond 1
10-Year Storm Event
11+12
(cfs)
0 .00
1 .26
3 .78
6.30
8 .81
11 .33
13 .85
16 .37
18 .89
21.40
23.92
24 .55
23 .29
22 .03
20 .77
19 .51
18 .26
17.00
15 .74
14.48
13 .22
11 .96
10.70
9.44
8 .18
6 .92
5 .67
4.41
3 .15
1 .89
0 .63
0 .00
0 .00
0.00
0 .00
0 .00
0.00
0.00
0.00
0.00
o .. oo
0 .00
0 .00
0 .00
0 .0 0
0 .00
2s/t-0
0 .00
-0.47
-0 .84
0.47
2.80
6.15
11.52
18 .74
27 .65
38 .59
51 .59
64 .76
76.27
86.23
94.78
101 .94
107.74
112.19
115.34
117.19
117.77
117.10
115.21
112 .12
107 .84
102.40
95 .82
88 .12
79 .38
69 .72
59 .17
48 .36
37 .91
27 .92
18 .77
10.39
3.48
-0.74
0 .27
-0 .10
0 .04
-0 .01
0 .0 1
0 .00
0 00
0.00
2s/t+O
0 .00
1.26
3 .31
5.45
9 .28
14 .13
20 .00
2 7 .88
37.62
49 .06
62 .51
76 .14
88.05
98.31
107 .01
114.29
120 .19
124 .73
12 7 .93
129.82
130.41
129.73
127.81
124 .66
120.30
114.77
108 .07
100.23
91 .27
8 1.27
70 .35
59 .17
48.36
37 .91
27 .92
18 .77
10 .39
3.48
-0 .74
0 .27
-0 .10
0 .04
-0 01
0 .01
0 0 0
0 00
Outflow
(cfs)
0.00
0 .86
2.08
2.49
3.24
3 .99
4.24
4 .57
4.98
5 .23
5.46
5 .69
5 .89
6 .04
6 .11
6 .18
6 .23
6 .27
6 .30
6 .31
6 .32
6 .31
6 .30
6 .27
6 .23
6 .18
6 .12
6 .05
5.94
5.78
5.59
5.40
5.22
5 .00
4 .57
4 .19
3.46
2 .11
-0 .50
0 .19
-0.07
0 .03
-0.0 1
0 .00
0 .00
0 .00
; I··, ... '" 1111 I I ':.·I 11 ;·; :.1 :t I 'I::
Storage
!f.!l
0
12
37
89
181
304
473
699
979
1 ,315
1 ,875
2 , 114
2,46 5
2 ,768
3 ,027
3 ,243
3,419
3 ,554
3 ,649
3 ,705
3 ,723
3 ,703
3,645
3,552
3,4 22
3 ,258
3,058
2,825
2,56 0
2,265
1 ,943
1 ,613
1 ,294
988
700
43 7
208
41
-7
3
-1
0
0
0
0
0
Depth
illl
0.0
0 .2
0 .6
0 .8
1.5
2.0
2 .2
2 .5
2 .9
3 .2
3.4
3 .6
3 .9
4 .0
4 .1
4 .2
4 .3
4 .3
4 .3
4.4
4.4
4.4
4.3
4 .3
4 .3
4 .2
4 .1
4.0
3 .9
3 .7
3.5
3.3
3 .1
2 .9
2 .5
2 .2
1 . 7
0 .9
0 .5
0.5
0 .5
0 .5
0 .5
0.5
0 .5
0 .5
Elevation
illl
2 72 .0
272 .2
272 .6
272 .8
273 .5
274 .0
274 .2
274 .5
2 74 .9
275 .2
275.4
275 .6
275 .9
276 .0
276 .1
276 .2
276 .3
276 .3
276 .3
276.4
276.4
276.4
276 .3
276.3
276 .3
276 .2
276 .1
2 76 .0
275 .9
275 .7
2 75.5
2 7 5 .3
275 .1
274 .9
274 .5
274 .2
273 .7
272 .9
272.5
272.5
2 72.5
2 7 2 .5
272.5
272 .5
272 .5
272 .5
Time
{m i n .)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
4 1
42
43
44
45
Inflow
{cfs)
0 .00
1.44
2 .88
4 .31
5.75
7 .19
8 .63
10 .07
11 .50
12 .94
14 .38
13 .66
12 .94
12 .22
11 .50
10.79
10 .07
9.35
8 .63
7 .91
7 .19
6.47
5.75
5.03
4 .31
3 .60
2 .88
2 .16
1.44
0 .72
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.0 0
0 00
0 .00
0 .00
Storage Routing Analysis
Detention Pond 1
25-Year Storm Event
11+12
{cfs)
0 .00
1.44
4 .31
7.19
10 .07
12 .94
15 .82
18 .69
21 .57
24.45
27.32
28 .04
26 .60
25 .17
23 .73
22.29
20 .85
19.41
17 .98
16.54
15.10
13 .66
12 .22
10 .79
9 .35
7 .91
6.47
5 .03
3 .60
2 .16
0 .72
0 .00
0 .00
0.00
0.00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0 00
2s/t-0
0 .00
-0 .53
-0 .55
1.19
4 .01
8 .73
15 .68
24 .68
35 .88
49.48
65.40
81.48
95 .84
108.53
119 .58
129.03
136.91
143 .23
148 .02
151 .32
153 .15
153.53
152 .50
150 .07
146.27
141 .12
134 .65
126 .88
117 .84
107 .54
96 .01
83 .98
72.34
61 .09
50 .2 1
39.71
29 .56
20 .28
11.77
4 .32
-0 .22
0.08
-0 .03
0 .0 1
0 .00
0.00
2s /t+O --
0 .00
1.44
3 .7 8
6 .64
1 1.25
16 .95
24 .54
34 .37
46 .25
60 .32
76.80
93.44
108.08
121 .00
132 .25
14 1.87
149.89
156.32
16 1.2 0
164 .56
166.42
166 .81
165.76
163.28
159.41
154 .18
147 .59
139 .69
130.48
120 .00
108 .26
96 .01
83 .98
72 .34
61 .09
50 .21
39 .71
29 .56
20 .28
11 .77
4 .32
-0 22
0 .08
-0 03
0 .01
0 00
Outflow
{cfs)
0 .00
0 .98
2 .17
2 .72
3.62
4 .11
4 .43
4 .85
5.19
5.42
5 .70
5.98
6 .12
6 .24
6 .34
6.42
6.49
6 .55
6 .59
6 .62
6 .64
6 .64
6 .63
6 .61
6.57
6 .53
6.47
6.40
6 .32
6 .23
6 .1 2
6.02
5.82
5.63
5.44
5 .25
5 .07
4 .64
4 .25
3 .72
2 .27
-0 .15
0 .06
-0 0 2
0 .01
0 .00
Storage
{f.fl
0
14
48
117
229
385
603
886
1,232
1,647
2 ,304
2 ,624
3,059
3,443
3,778
4 ,064
4 ,302
4,493
4 ,638
4 ,738
4J94
4,805
4 ,774
4,700
4,585
4,429
4 ,234
3,999
3 ,725
3,413
3 ,064
2,700
2,345
2,001
1,669
1,349
1,039
748
481
241
61
-2
1
0
0
0
Depth
illl
0 .0
0 .2
0 .6
0 .9
1.8
2 .1
2.4
2 .8
3.1
3 .3
3.6
4 .0
4 .1
4 .3
4.4
4 .5
4 .6
4.7
4 .7
4 .7
4 .8
4 .8
4 .8
4 .7
4 .7
4 .6
4 .6
4 .5
4.4
4 .3
4 .1
4 .0
3 .8
3.6
3.4
3 .2
3.0
2 .6
2 .3
1.8
1.0
0 .5
0 .5
0 .5
0 .5
0 .5
Elevation
illl
272 .0
272 .2
272 .6
272 .9
273 .8
274.1
274.4
274 .8
275 .1
275 .3
275.6
276 .0
276 .1
276 .3
276.4
276.5
276 .6
276 .7
276 .7
276 .7
276 8
276 .8
276 .8
276 .7
276 .7
276 .6
276 .6
276 .5
276.4
276 .3
2 76 .1
276 .0
275 .8
275 .6
275.4
275 .2
275 .0
274 .6
274.3
273.8
273 .0
272 .5
272 .5
272 .5
272 .5
272 .5
I
Time
(min.)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Inflow
(cfs)
0.00
1.63
3 .25
4.88
6.50
8.13
9.75
11 .38
13 .00
14 .63
16.25
15.44
14 .63
13 .81
13.00
12.19
11.38
10.56
9.75
8.94
8 .13
7 .3 1
6.50
5 .69
4 .88
4.06
3.25
2.44
1.63
0.81
0 .00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 00
0 .00
Storage Routing Analysis
Detention Pond 1
50-Year Storm Event
11+12
(cfs)
0.00
1.63
4.88
8 .13
11 .38
14 .63
17 .88
21 .13
24.38
27.63
30 .88
31.69
30 .06
28.44
26 .81
25 .19
23 .56
21 .94
20.31
18 .69
17.06
15.44
13.81
12.19
10.56
8.94
7.31
5 .69
4 .06
2.44
0.81
0.00
0.00
0.00
0 .00
0.00
0 .00
0 .00
0 .00
0.00
0.00
0.00
0.00
0 .00
0 .00
0.00
2s/t-O
0 .00
-0.60
-0 .25
1.94
5.40
11.54
2s/t+O
0 .00
1.63
4.27
7 .87
13.32
20.03
20.14 29.42
31.06 41.27
44.75 55.44
61.13 72 .38
80 .09 92.00
99.47 111 .78
116 .91 129 .53
132.44 145.34
146 .11 159.26
157.94 171.30
167.97 181 .51
176.23 189.91
182 .74 196.54
187 .54 201.43
190.66 204.60
192 .13 206.10
191.98 205.95
190.24 204.17
186 .92 200.80
182.07 195.86
175 .71 189 .39
167 .87 181.40
158 .56 171 .93
147.82 161 .00
135 .68 148.64
12 2.95 135 .68
110.44 122 .95
98 .15 110.44
86.08 98 .15
74.37 86.08
63 .05 74.37
52.11 63 .05
41.54 52 .11
31 .33 41 .54
21 .89 3 1.33
13.25 2 1.89
5 .34 13 .25
0.40 5 .34
-0 .15 0.40
0 .05 -0 .15
Outflow
(cfs)
0 .00
1 .11
2 .26
2.96
3.96
4.24
4.64
5.10
5 .34
5.63
5 .96
6 .16
6.31
6.45
6 .57
6 .68
6 .77
6 .84
6 .90
6 .94
6 .97
6 .98
6.98
6 .97
6 .94
6 .89
6.84
6.77
6 .68
6 .59
6.48
6.37
6 .25
6.14
6.04
5 .86
5 .66
5.47
5.29
5.11
4.72
4 .32
3.96
2.47
0.27
-0.10
Storage
.{f!l
0
15
60
147
281
474
743
1,085
1,503
2,003
2 ,760
3,169
3,697
4 , 167
4,581
4,939
5 ,242
5,492
5,689
5 ,835
5,929
5 973
5,969
5,916
5,816
5,669
5,476
5 ,23 9
4,957
4,632
4,265
3,879
3,501
3 , 129
2,764
2,407
2,061
1,727
1,405
1,093
798
527
279
86
4
-1
Depth
illl
0 .0
0 .2
0 .7
1.0
2 .0
2 .2
2 .6
3 .0
3 .3
3 .6
3 .9
4.2
4.4
4 .5
4 .7
4 .8
4 .9
5.0
5.1
5.1
5.1
5.1
5.1
5.1
5 .1
5.1
5 .0
4 .9
4 .8
4 .7
4 .6
4.4
4 .3
4.2
4 .0
3 .8
3 .6
3.4
3 .2
3 .0
2 .7
2.3
2 .0
1 .1
0 .5
0 .5
Elevation
illl
272.0
272 .2
272 .7
273 .0
274 .0
274 .2
274 .6
275 .0
275.3
275.6
275 .9
276.2
276.4
276.5
276.7
276.8
276 .9
277 .0
277 .1
277.1
277 .1
277 .1
277 .1
277 .1
277 .1
277 .1
277.0
276.9
276.8
276 .7
276 .6
276.4
276 .3
276.2
276.0
275.8
275.6
275.4
275.2
275 .0
274 .7
274.3
274 .0
273 .1
272 .5
272.5
I
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
4 2
4 3
44
45
Inflow
(cfs)
0 .00
1.70
3 .39
5.09
6.79
8.49
10 .18
11 .88
13 .58
15 .27
16.97
16.12
15 .27
14.42
13 .58
12 .73
11 .88
11.03
10 .18
9 .33
8.49
7 .64
6.79
5.94
5.09
4 .24
3 .39
2 .55
1.70
0 .85
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
0.00
0.00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
Storage Routing Analysis
Detention Pond 1
100-Year Storm Event
11+12
(cfs)
0.00
1.70
5 .09
8.49
11 .88
15 .27
18 .67
22.06
25.46
28 .85
32 .24
33.09
31 .39
29 .70
28 .00
26.30
24 .61
22.91
21 .21
19 .52
17 .82
16 .12
14.42
12 .73
11.03
9 .33
7 .64
5 .94
4.24
2 .55
0.85
0 .00
0 .00
0 .00
0.00
0.00
0.00
0.00
0.00
0.00
0 .00
0 .00
0 .00
0 .00
0 .00
0 .00
2s/t-0
0 .00
-0 .63
-0 .14
2 .23
6 .13
12.80
22 .02
33 .78
48.43
65.86
86.03
106 .68
125 .30
141.93
156.60
169 .34
179 .38
186 .53
191 .21
193.76
194.49
193 .67
191 .50
188 .19
183 .90
178.77
172 .79
165.24
156.16
145 .57
133.50
120 .81
108.34
96.09
84.05
72.41
61 .15
50 .28
39 .77
29 .62
20 .33
11 .82
4 .3 5
-0 .2 1
0 .08
-0 .03
2s/t+O
0 .00
1.70
4.46
8 .35
14 .11
21.40
31.47
44 .08
59.24
77 .27
98 .10
119 .12
138 .08
155.00
169 .93
182.90
193.95
202 .29
207 .75
210.72
211.58
210.61
208.09
204.23
199 .22
193.24
186.41
178.73
169.48
158 .70
146.42
133 .50
120.81
108 .34
96 .09
84.05
72.41
61.15
50 .28
39 .77
29 .62
20.33
11.82
4 .35
-0 .2 1
0 .08
Outflow
(cfs)
0 .00
1.16
2 .30
3.06
3 .99
4 .30
4.72
5.15
5.41
5.71
6 .04
6 .22
6.39
6.53
6.67
6 .78
7 .28
7 .88
8.27
8.48
8 .54
8.47
8 .29
8 .02
7.66
7.23
6 .81
6.74
6.66
6 .57
6.46
6 .35
6 .23
6.13
6.02
5.82
5.63
5.44
5.25
5.07
4 .65
4 .25
3 .73
2.28
-0 .14
0 .0 5
t I . ,-i 11 I i { I I 11 1; t 1 I I ' . ..~ ! ' \.,
Storage
~
0
16
65
159
304
513
802
1, 168
1,615
2, 147
2,943
3 ,387
3,951
4,454
4,898
5,284
5,600
5,832
5,984
6,067
6 091
6,064
5,994
5,886
5,747
5,580
5,388
5, 160
4,885
4,564
4 ,199
3 ,815
3,437
3 ,066
2 ,702
2 ,347
2,003
1,672
1,351
1,041
749
482
243
62
-2
Depth
ill.l
0 .0
0 .2
0.7
1.0
2 .0
2 .3
2 .7
3 .1
3 .3
3.7
4.0
4.2
4.4
4 .6
4 .8
5.0
5.1
5.1
5.1
5 .2
5 .2
5 .2
5 .2
5.1
5 .1
5 .1
5.0
4 .9
4 .8
4 .7
4 .5
4.4
4 .3
4 .1
4 .0
3 .8
3.6
3.4
3.2
3.0
2.6
2.3
1.9
1.0
0 .5
0 .5
Elevation
ill.l
272 .0
2 72 .2
272 .7
273 .0
274 .0
274 .3
274 .7
275 .1
275 .3
275 .7
276 .0
276 .2
276.4
276.6
276 .8
277 .0
277 .1
277 .1
277.1
277.2
277.2
277 .2
277 .2
277 .1
277.1
277 .1
277.0
276.9
276 .8
276 .7
276.5
276.4
276 .3
276 .1
276 .0
275 .8
275 .6
275.4
275.2
275.0
274 .6
2 74 .3
2 73.9
273 .0
272 .5
272.5
I
I
I
EXHIBIT A
Pre-Development Drainage Area Map