FLOOD00927

• Designation Number: 216
• County: Logan
• Community: Sterling
• Stream Name: Sand Creek and Pawnee Creek Overflow
• Title: Floodplain Information and Drainage Plan - Sand Creek and Pawnee Creek Overflow
• Date: 5/1/1983
• Designation Date: 7/1/1983
• Floodplain - Doc Type: Floodplain Report/Masterplan

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Irriqdtiol1llitches
Four ditch companies operdte Cdlldls which traverse the study area.
These include the; Springdale, SterlingNo.l,Pawnee, and Nort hSterling.
Approximate di tch ,,,pad tic$ .wc a~ f"llo,.'s:

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Ditch
-

Capacity
(c.f.s.)
650
300
90
200

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North Sterling
Pawnee

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Sprlngdale
SterllngNo.l

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All can be expected to carry water into and out of the area during floods.
Becau$e of the uncertainties of response of the 4 ditches, they were not
considered In the hydrologic analysis. All of the ditches have carried
water from the South Platte River during past flood events; there fore the
canal embankments are likely to fail even during relatively minor fl ooding.
Where a failure might occur is difficult to predict, and the effect of a
breach on the flood peak in a given watershed is likewise unpredictable.
Thatis,afloodpeakmaybeincreascdascanal flows drain into the
Pioneer Ditch floodplain, or a peak moy be reduced should floodwaters
from above a given ditch be intercepted and diverted out of waters hed. In
either case, for the critical l00~year event, peak flows from the drainage
area tributary to Pioneer Ditch arc of such magnitude as to wake the effect
of ditch failures relatively smal1- perhaps less than 20 percent and
should be ignored.

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