FLOODC00179

• County: Morgan
• Community: Wiggins
• Stream Name: Kiowa Creek
• Basin: South Platte
• Title: Operations and Maintenance Manual - Kiowa Creek Flood Protection Project
• Date: 1/1/1989
• Prepared For: Wiggins, Department of Local Affairs
• Prepared By: CWCB
• Floodplain - Doc Type: Floodplain Report/Masterplan

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A Division of Versar, Inc.

December 19, 1988

Mr, John Holdren
Town ~lanager
P,O, Box 287
Wiggins, CO 80654

Dear John:

SUBJECT: KIOWA CREEK FLOOD PROTECTION IMPROVEMENTS
TOWN OF WIGGINS PROJECT I AND II
PROJECT NO. 86136.01

This letter is to certify that to the best of our knowledge and belief, the
construction on the above referenced projects was completed in accordance with
the plans and specifications as approved by the Town of Wiggins and the
Colorado Water Conservation Board. This certification is based on weekly site
visits by the Project Engineer, review of soils testing and review of as-built
drawings, The daily inspection was provided by John Holdren of the Town of
Wiggins with supervision by ARIX. Soils testing was performed under the
supervision of registered professional engineers. The location and elevation
information shown on the as-built plans was determined by independent firms
under the direction of certified surveyors.

The plans and specifications for the projects were prepared in accordance with
the guidelines in Design and Construction of Levees, EM 1110-2-1913, Corps
of Enginpers and Natlona1 Flood Insurance Program and Related Regulations,
FEMA. In general, the engineering design included the following items:

- A zoned embankment consisting of a clay core and sand shell was constructed
to minimize seepage, The stability analysis of the embankment indicated a
safety factor of 2,0. The embankment slopes are 3:1 with a top width of l2
feet, Settlement in the embankment was controlled by compacting the soil
to 95% of the standard proctor density and by maintaining moisture to
within 2% of optimum.

- A minimum freeboard of 3 feet above the lOO-year flood elevations was
provided. The 100-year flood elevation was determined by using the Corps
of Engineers HEC-2 computer model, An additional one foot of freeboard was
added at all structures, An additional one half foot freeboard was added
at the upstream end tapering to 0 feet at the downstream end.

800 Eighth Avenue

Greeley, CO 80632-2021

303-356-3930