FLOOD10207

• Designation Number: 503
• County: Jefferson
• Community: Unincorporated Jefferson County
• Stream Name: Woman Creek, Walnut, Upper Big Dry and Rock Creek
• Basin: South Platte
• Title: Drainage & Flood Control Master Plan - Rocky Flats Plant
• Date: 4/1/1992
• Designation Date: 9/1/1999
• Floodplain - Doc Type: Floodplain Report/Masterplan

TABLE IV-9

TABLE IV-IO

COMPARISON OF lOO-YEAR PEAK FLOW MASTER PLAN, ASI, UD&FCD, USACE

COMPARISON OF TOTAL RUNOFF VOLUME MASTER PLAN, ASI, USACE, UD&FCD

I Mallltr Plan l~YeBl" Peak Flow (cfs)
I ASI' USACE
Basin I ElelDeot Site Bas'. Master Master NOTES
Noli. N~ No. Pl..' Pla.' AS" USACE" UD&FC~
CUHP SWMM
A. Walnut Creek Basin @S.R.D.C. 139 2 100 m 23 20 210 m 4,5
B. Runoff to North Walnut Creek 348 3 5 m 240 200 <iOO m 4,5
Diversion Dam
C. McKay Ditch Start 135 4 m 220 210 m m 4,6
D. McKay Ditch End 134 6 m m 210 220 m m 4,6
E. End of Landfill Reservoir Basin 141 1l 13 250 230 850
F. Runoff to Pond A-4 169 12 434 --- 650 240 690 --- 4,7
G. Runoff to Pond 8-5 151 14 334 m 690 480 610 ---
H. Confluence of North & Soulh 140 16 15 1,700 810 1,610 4.7
Walnut and Landfill Reservoir~
I. Walnut Creek at Indiana Street 129 17 16 1,300 2,300 1,160 3,080 m 4,5
1. Great Western Trib. at Indiana 353 18 --- m 240 220 --- ---
K. Inflow 10 Great Western Reservoir 350 19 1,900 3,200 ~060 m 3,900 4,8
I.. Woman Creek Basin at S.B.D.C. 119 21 39 --- 130 100 470 5,6
M. South Interceptor Ditch 122 24 51 120 92 370 ---
N. South Interceptor Ditch 121 25 52 --- 220 210 500 ---
O. Woman Creek Diversion Dam 113 '" 54 _u 690 400 2,390 --- 4,8
P. Woman Creek at Indiana Street 108 -- 60 1,300 1,<iOO --- 4,630 u_ 9
O. Standley Lake Tributary at Indiana 124 31 --- 240 180 130 --- ---
R. Inflow to Standley Lake 301 -- --- 5,400 5,500 --- --- 5,700

MAS1U ASI' iDO-YEAR TOTAL RUNOFF VOWME (AF)
PLAN SITE
BASIN ElEMENT NO. USACE' MAS1ER NOTES
NO, (Oct..19ft9) PLAN' ASI' UD&FC04
SWMM
A. W.llnut Creek (!l) S.B.D.C. 139 2 6 6 5
B. Runoff to North Walnut Creek Diversion 348 3 --- 31 48 --- 5
D.m
C. McKay Ditch Start 135 4 --- 33 49 --- 6
D. MtKay Ditch End 134 6 --- 33 69 --- 6
E. End of Landfill Reservoir Basin 141 11 --- 34 39 --
F. RUnoff to Pond A-4 l69 12 107 64 62 --- 7
G. Runoff to Pond B-5 151 14 89 7I 65 ---
H. Confluence of North & South Walnut 140 16 --- 186 169 --- J
and Landfill Reservoirs
I. Walnut Creek at Indiana Street 129 17 440 296 318 --- 5
J. Great Western Trib. at Indiana 353 18 33 27 31
K. Runoff to Grea.t Western Reservoir 350 19 --- 480 478 540 5
I.. Woman Creek at S.B.D.C. 119 21 --- 21 50 --- 8
M. South Interceptor Ditch 122 24 --- 15 11 ---
N. South Interceptor Ditch 121 25 --- 25 2l<
O. Woman Creek Diversion Dam 113 '" --- 116 140 --- 8
P. Woman Creek at Indiana Street 108 301 --- 301 --- ---
O. Standley Lake Tributary at Indiana 124 31 --- 2l< 20 ---
R. Inllow to Standley Lake 301 --- 1700 --- l<iOO

NOTES:

'"

From ASI Task 06, "Storm Runoff Ouantity for Various Design Events; Table 5. 6-Hour, loo-Year Storm, Present Development Conditions
6-Hour, 100- Year Storm, Present Development Conditions
From UD&FCD FHAD for Big Dry Creek, Greiner Engineering 11/86, revised 12/89. 2-Hour, loo-Year Storm, Future Development Conditions.
The spill flow rate used by ASl is assumed to be directly additive to the basin runoff flow, hence the ASI flow is appronmate.
ASl Table 5 induded approximately 24() cfs spilled from Coal Creek. Subtract 240 cfs from tabulated ASI value to obtain value in this table.
ASJ T.able 5 included 240 cIs spilled into basin from Coal Creek minus 110 cfs spilled out of basin to North Walnut Creek. Subtract 130 cfs from tabulated ASI value
to oblain value in this table.
ASI Table 5 included 110 ds spilled into basin from Walnut Creek (McKay) Diversion Canal. Subtract 110 cfs from ASI tabulated value to obtain value in this lable.
ASI Table 5 included 1100 ds spilled inlo Kinnear Diteh (Woman Creek. basin) from Coal Creek. Subtract 1100 cis from Table 5 of ASI report to obtain values in
this report
No comparison is possihle with ASI because ASI did not include the majori/Y of Sou/h Woman Creek basin.
From "Draft Flood Plain Delineation." Hydrologic Analysis Interagency No. DE-Al34-90RF 57446, December, 1991. U.S. Army Corps of Engineers.

ASI Table 6 included approximately 82 AF spilled into basin from Coal Creek minus 11 AF spilled out of basin to Norlh Walnut Creek. Subtract 71 AF from tabulated
ASI value to obtain value in this table.

From ASI Task 06, "Storm Runoff Quantity for Various Design Events," Table 6. 6-Hour, HXJ.. Year Storm, Present Development Conditions

From U.S. Army Corps of Engineers, Pre-decisional Draft, Review Report of the Great Western Reservoir Pre-Feasibility Study, 10/89. 3-Hour, loo-Year Storm, Present
Development Conditions.

6-Hour, 100- Year Storm, Presenl Development Conditions.

2-Hour, loo-Year Storm. Future Development Conditions.

ASI Table 6 included approximately 82 AF spilled from Coal Creek. Subtract 82 AF from tabulated ASI value to obtain value in this table.

ASI Table 6 induded II AF spilled into basin from Walnut Creek (McKay) Diversion Canal. Subtract 11 AF from ASr tabulated value to obtain value in this table.

ASI Table 6 included 120 AF spilled into Kinnear Ditch (Woman Creek basin) from Coal Creek. Subtract 120 AF from tabulated ASI value to obtain values in this table.