FLOOD03288

• County: Morgan
• Community: Wiggins
• Stream Name: Kiowa Creek
• Basin: South Platte
• Title: Kiowa Creek at Wiggins Flood Warning System
• Date: 9/1/1990
• Prepared For: Wiggins
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

1. INTRODUCTION

1.1 Purpose
The purpose of this report: is to describe the hydrologic
studies conducted to develop a preliminary layout and design
of a flood warning system for the tmm of Wiggins, Colorado.
This report was prepared for t.he Cole)rado Water Conservation
Board (CWCB), at their reql.le,st:, to enhance the Flood Op-
erations Plan for the town oj.: Wiggins. 1~ flood warning sys-
tem is required because there are two manually operated clo-
sure structures for the exist:ing levee system.

1. 2 Scope
This study is limited to pre,viding technical assis1:ance and
direction to the state of Colorado and is not to be regarded
as a final design document. The analysis of flood warning
times was based on the project design hydrology, developed
for the flood control project, whie,h was provided to the
corps by the CWCB. Methodology for establishing the dis-
charge - frequency relationship was not reviewed as part of
this study. Flood hydrographs were derived utilizing rain-
fall - runoff methodology wit:h Snyder's unit graph constants
developed for Cherry Creek. st,ream:Elow routing was based on
the Modified-Puls method, using storage outflow relationships
based on backwater computations.
Also included in this report. is a listing of equipment re-
quired to construct a flood warning gage,. a description of
the operation of a flood warning system, and a discussion of
the maintenance necessary to e,nsure the integrity of a flood
warning system over time.

1. 3 Authority
Authority for this study is contained in section 22 of Pub-
lic Law 93-251 -- Water Resou.rces Development Act of 1974,
commonly referred to as "Planning Assistance to States".
section 22 authorized cooperat.ion with states in the prepara-
tion of comprehensive plans for the development, utilization
and conservation of the water and related resources of drain-
age basins located within t:he, boundaries of the state. As
amended by section 921 of the Water Resources Development Act
of 1986, expenditures in anyone sta'te cannot exceed $300,000
in anyone year. This study was funded as part of the allot-
ment for the state of Colorado during Fiscal Year 1990. A
Plan of Work document, prepared by 'the CWCB and modified by
subsequent communication, Gont:ains the specific request to
initiate this study. pert:inent project documents are con-
tained in Appendix B.

1.4 Report Organization
The report is subdivided into
dicies. Those maj or sections:,
each are provided below:

seven sections and 2 appen-
and a brief description of

section (1) is the introduct:ion.

1.