FLOOD02246

• County: Boulder
• Community: Boulder
• Stream Name: Bullhead Gulch
• Basin: South Platte
• Title: Bullhead Gulch Hydrology Report
• Date: 8/22/1997
• Prepared For: FEMA
• Prepared By: Taggart Engineering Associates, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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August 25, 1997 BHIOOFI3.CHO

CClFFICIENT CClFFICIENT
(REFLECTING 'HE TO PEMl (RELATED TO PEAK RATE IF RlMf'F)

114

.183

CPLCl1.ATED LHlT HYORCXi!W'tt

TIME ro PEAK rulE OF C()ICENTRATlCW PEAK RATE IF Rl.HJFF l,m HYORCXiRAPIi PEAl 'IO.LK (J' RlJO"F
(HIN) (H[N) (CFS/SIJ'lI) (CFS) (Ar)

5.94

21.00

2041.118

1.71

65.31

..... t<<)TE TtE: mE TO PEAK IS CALcu.ATED BASED ()( Ttf: TIME OF CCWCENTRAT!lJt PROVIDED BY TlE USER.
REPlACING THE CIIE CllflUTEO BY ClWD lTP- 4.64)

WIDTH AT 50" 15. HIN. WIOTH AT 75" 9. HIN. GO" .24 K75".33

RAINFAlL LOSSES INPUT WI BASIN DATA

MAX. PERvtCJJS RH. .. .40 IN. MAX. IHPERVICJJS REf. .10 IN.
INFllTRATI~ .. 4.511 IH./KI.. DECAY" .QOl80/SECCNJ FNINFL".60 IN./tR.

THE LNIT
HYI><liI!APH

mE llHT
HYI><liI!APH

TUE IJrllT
HYI><liI!APH .

o.
5.
10.
15,

20. 28.
25. 22.
30. 17.
JS. 13.
BASIN OJK:NT:

10. ..
..
0,
o.
J north half AWl basin 3

40,
45.
sa.
o.
Sl.8BASINIO-

0,
63,
51.
38.
BASINID: J

.- STCIlI'INO."

DATE iJl. RET\.P.N PERlOO .. lOOYEA/l.

--

INClID'ENT TalAl STCI!I1 lNClID'ENT TOTAL. SHJ!H
mE RAINFALL EXCESS HYI><liI!APH mE RAINfAlL EXCESS HYI><liI!APH
(PUN.) ({N) PREelP (CfS) (HIN,l (IN) PRECI? (CFS>
0, ,00 .000 0, 55. ,11 ,065 37.
5, .03 .000 o. sa, ,11 065 33,
10. .08 .001 o. 65. ,11 .065 29.
15. .11 .020 I. 70, .85 .012 23.
20, " .036 3 75. .85 .012 15.
15. .38 075 7. 80. .03 .085 10.
30. 613 .614 45 85. .03 085 7.
35. .38 325 56 90 .03 .005 5.
40 .zz .1613 54 95. .03 ,",5 3.
45. .17 .122 48, 100. .03 .005 3,
50 .14 .091 43. IDS. ,OJ ,005 2.
TOTAl PlI.ECIP. .. 3.t2(1.fO..RRAIN" 2.70) EXECESSPRECIP. -1.721 INCHES
VQLK OF EXCESS PRECIP" 3, ACRE-FEET
PEAK 0 . 56.CfS mEOF?[.6X.. 35.I1IN.
INFILT.. 4.50 IN/ffI: ~CAy.. .00180 FNINf- .60IN/IfI.
KAX.Pf:RV.RH.".40 IN. HAX.llfl,RET.-.IOIN.
RATIC>>W. FlFJ'U.A C .. 55
1- S.2IN[HES/1-OJl.
,. 20 5 ACRES
o. 58.CFS
U,Q,F.G.D C\JfP Rt;taF AHAUSiS EXECUTED (Jrf DATE ATTlHE

ct.HPE/PC '/ERSION I'OJIFIED IN JAMJARv 1985
PRIHT QPTIlJrl IU'BER SELECTED F(Jl. THIS BASIN IS 7
3l1.LHEAO Q.LCH: IOO-YII.: FEHA FrS: 8/25/97 (BHlOOFIJ.OUladdH&AGC/pond3

I BASIN 10: 333 -- BASIN aJt1ENT: SlIlBASIN 10- J south half FIiAO bilsin J to l0ll1svllle pond3

AREA OF BASIN LEt<<iTH OF BASIN OIST TO CENTROID [11P[RVlllJS AREA SlOPf: lMIl I)JlATI~
rSl1llJ om (HI) (PeT) (FT/FT) [HIN)

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.03 19

10

5.00

17.35

ll46ll

COEFFICIENT
(REFLECTlt<<i TlI'IE TOPEAJ()

COfJFICIENT
(RELATED TO PEAK RATE OF RUNOFF)

.114 .182

CAlCl1.ATEO LINn HYQROOWlH

TIME TO?EM TIME OF CCJrICENTRATI()t Pf:AA RATE OF RlJrlCfF UNIT HY~ ~ va.1J€ {F RlJIFF

3