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 BHlOOFI3.CHO
IS. 118 65. Z7 105. o.
JO 96. 10. 23 0 o.
35 " 75 " o. o.
BASIN 10' '" .. BASINC(Jt(NT: SL88ASIN [{)o 60
.....STCflI11(1, .. CATE ~ RHLItN PfRICO .. lOOYEAA
[~[~NT TOTAl 5T{J!I1 INCREMENT TOTAL 5T{J!I1
TlHE RAINFAlL EXCESS HYIlR(l;AAl'H TlHE RAINFALL EXCESS HYIlR(l;AAl'H
01lN.) (iN) PlU:CIP (CFS) (H(N,) (IN) PRECIP (CFS>
.
o. .00 .000 o. OS. .03 .006 83. .
5. .03 .000 o. 90. 03 .006 71. .
10. ,OS ,002 o. OS, .03 .006 60,
IS IZ .025 3. 100. .03 .006 52,
20 11 .043 10 105, .03 .006 45, .
IS. 38 088 23. 110. 03 .006 39.
30. 68 .615 99 115. ,03 .006 33.
35. 38 .327 179 120. .03 ,006 29,
40. 21 .170 106. 125. .00 000 14.
45. 17 .124 205. 130. .00 ,000 16,
so. .14 .093 196, 135. .00 ,000 12, .
55. .11 ,066 179. 140, .00 .000 9.
60. .11 .067 163. 145. ,00 .000 6. .
65 .11 ,067 151. ISO. .00 .000 5. .
10. .05 .014 134, 155. ,00 ,000 4.
75, 05 .01-4 115. 1"'. .00 ,000 3,
90. .03 .006 !lll. . 165, .00 .000 2. .

TOTAL PRECIP. .. 3.12 (l.1-O..R RAIN.. 2.70) (XECESS PRECIP. .. 1.772 INCtES
VClll'E Cf" EXCESS PRECIP .. 15. ACRE-FEET
PEAK a.. 206. CFS TIME CE PEAK.. 40. HIN.
ItFllT.- 4.50 IN/If!: DECAY" .00180 FNINF...6O IN/iii.
lW.PERV.RET.- AD IN. "'-AX.IHP.RET,- .to IN.
U.O. F .C.O. ow R1JlCfF NW. 'f$IS EXECUTED CH DATE AT mE

UtFE/PC VERSICJlI'OJIFIED IN JJHJARY 1985

PRIHT CPTICW tU6ER SELECTED FCR THIS BASIN IS 7

BlLllVD lllOt: lOO.VR: FEHA ns: 8/25/97 (BHIOOfI3.CHlladlfiUbC/p00d3

BASINlD: 61

.. BASIN rotIEHT: SlBBASIN 10- 61

AAEA IF BASIN lEI<<iTH Cf" SASEN 01$1 TO CENTROID UftRVICllS AREA SLOPE lJtlT lX.RATICIt
(5(J1[) (Hll (Hi} (PCT) (FT/FT) (HIM)

.17

51

.18

40.00

.0220

5.00

COEFFICIENT CCHFICIEHT
(REFLECTING TIME TO ?EM) (RELATED TO PEAK RATE rI' RlHJFF)

.093 .400

c.aLClUTED LNIT HYtlROC.RAPIi
TIME ;0 ?EAK PEAK RATE OF RI.KfF LNlT lfI()ll.o:iRAP PEAK m.Lt( OF Rll<<F
(HIN) (CFS/5(J1Il (CFS) (/Ii)

'.94

3459.01

588.03

9.07

WIOTH ~T 50 - 9. MIN. WIOTH AT 75 - 5. MIN. KSO - .35 1(75. 45

RAINFAlL LOSSES IfrtPUT '~I BASIN DATA

IW" PfRVIOJS RH. - .40 IN. !1AX. IHP[RVIM RH. .;0 IN.
IHFIlTRATlIJt-3.27 !N."~ DECAY" 00180/SECCtIO FNINFl- .52IN./lft.

TlHE "'IT TIll "'IT TlHE "'IT
HYIlR(l;AAl'H HYIlR(l;AAl'H HYIlR(l;AAl'H
o. o. 20. 114 40. 9,
5. 454 25. 60 45, o.
10 414 30, 31. o. O.
15. 216. 35. 17, 0, o.
BASIHIO: 51 BASIHCCJ11[HT' Sl68A$IN 10- 61
-*ST()lH~, - DATECIl:RE~PERlOO-1OOYEAA
INCREMENT TOTilL ST{J!I1 INCREHENT TOTAl. 5T{J!I1
TlHE AAINFilLL EXCESS HY""",,,," TlO< RAINfAll EXCESS HYlJI!OOl4PI<
(HIN.) (IN) P!l:ECIP (eFS) (HIN.) (IN) P!l:ECIP (CfS) .

51