FLOOD05008

• County: Prowers
• Community: Granada
• Basin: Arkansas
• Title: Appendix I Hydrology ‎(Draft)‎ Detailed Project Report - Investigation For Flood Protection
• Date: 7/10/1973
• Floodplain - Doc Type: Floodplain Report/Masterplan

were used to define the 2 and 20 percent curves for drainage area sizes
not defined in the study area. TIle plot of drainage areas used to
develop the two curves on plate 3 include the records of four streams
in the adjacent Kansas River drainage area, tlfO crest-stage partial-
,
record stations in the study area, one station in the Arkansas River

drainage area adjacent to the stud~ area, and seven gaging stations in

the study area. A listing of pertinent data for the 14 locations is

given in table 1.
20. The peak frequency curve for Wolf Creek at Granada was constructed

by use of the ratio of Q/QUllG for the 5 and SO-year floods from the

frequency development curves for the Arkansas River from John ~Iartin Dam

to Great Bend, Kansas. With the use of these ratios and the peak of the

uni t hydrograph, the 20 percent and 2 percent flow peaks were determined.

TIlese values were plotted on log probability coordinates and a line drawn

through the points. To complete the curve, 2S-)'ear likeliness was added.

TIlis adjustment was based on the average length of streamflow records

that were used in the determination of the frequency development curves.

Likeliness factors were not considered during construction of the develop-

ment curves. TIle peak frequency curve for Wolf Creek at Granada is shown

on plate 4.

21. Coincident FlOl~. Flow conditions on the Arkansas River coincident

with peak flows on Wolf Creek were required in order to determine starting

elevations for water surface profiles. Records of flow on the Arkansas

River at Lamar and Holly, Colorado were used with peak flows on Wolf Creek

to develop coincident flows. TIlese were plotted to determine the curve

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