FLOOD08888

• County: Prowers
• Community: Holly
• Stream Name: Arkansas River
• Basin: Arkansas
• Title: Detailed Project Report - Public Law 87-874 Project
• Date: 3/1/1977
• Prepared For: Prowers County
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

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TABLE 5

ADDITIot:AL PROTECTION ACAINST 1'1.00115 011
ARKANSAS RIVER Eo '!WO RUTTE CHFEK
SECOND ADl!ElJ INCHEHENT

Average Average
Annual Annual Excess
Frequency Benefits Cost* Benefits BIC Ratio
38 0 0
50 2,600 2,900 -300 .89
100 8,400 7,1\70 530 1.07
SpF 31,000 16,500 14,500 1.87

* Includes annual cost for operation & maintenance.

The sum of annual benefits for botn firat and second added increments
is $197,nOO. The total annual costs is $121,500, with a tatal project
first cost of $1,744,000. The benefit to cost ratio is 1.62.

This plan would provide a high degree of flood protection ta !lolly
for floods originating from all three sources of flooding and affords
a scale of development for which local interests are capable of sup-
porting financially. Therefore, this plan was selected as the most
feasible plan of improvement for protection of Holly against potential
flooding from Wild Horse Creek, Two Butte Creek, and the Arkansas River.

THE SELECTED PLAN

PLAN I1ESCRIPTION

The recommended plan of improvement, presented on Plate 5, is a
levee to protect the town of Holly and adjacent lands from standard
project flood flows originating on the Arkansas River, Wild Horse
Creek and Two Butte Creek. From the point of beginning, ,north of Holly,
the levee will extend Boutb along the left bBnk of the tributary ,to
its junction with the Arkansas River where it will turn eas t following
the north side of the mainstem to the point of termination, east of
Colorado State Highway 89. The levee will extend downstream a suffi-
cient distance to prevent backwater from entering the town behind the
levee.

Levee top width will be a uniform 12 feet to permit access for
maintenance, with riverside slope of 3 horizontal to 1 vertical and
lands ide slope of 2.5 horizontal to 1 vertical. The levee height north
of the AT&SF Railroad track would provide a 4-foot freenoard above max-
imum water surface. The reach between the railroad and Colorado High-
way 89 would provide 5 feet of freeboard to account for the contin-
gencies that might arise from Two Butte Creek flowing from the Bouth.

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