PUB00015

• Year: 1998
• Title: Stewardship of Colorado Stream Corridors
• CWCB Section: Watershed & Flood Protection
• Author: CWCB
• Description: Statewide River rehabilitation and floodplaim needs inventory
• Publications - Doc Type: Tech Report

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PROJECT REPORT TO
THE COLORADO WATER CONSERVATION BOARD
FOR "THE STEWARDSHIP OF STREAM CORRIDORS
IN COLORADO"
January, 1998

PURPOSE
The purpose of the study was to obtain input from local communities and stakeholders to guide
the CWCB regarding the feasibility of developing a new or expanded comprehensive approach
and provide financial resources for local governments and special districts to better manage and
address flood-related and multi-objective river issues. Colorado has undergone a significant
growth trend, which is expected to continue. The state has also experienced significant flooding
in some of its more populated areas. The successes, shortcomings, and needs resulting from this
combination of population growth and flood events are very valuable input to properly manage
and deal with Colorado's watersheds, stream corridors and floodplains.

LEGISLATIVE AUmORIZATION -STATE STRATEGY
The Water Conservation Board, though the state wide needs assessment process is hereby
responding to Senate Bill 97-008, Section 9 which states: "Statewide river rehabilitation and
floodplain management needs inventory. The Colorado water conservation board is hereby
authorized to expend up to one hundred thousand dollars ($100,000) from the Colorado water
conservation board construction fund to develop a scope of work and contract for services to
conduct a statf!Wide inventory of river channel restoration and floodplain management needs.
The findings of the needs assessment will be the basis for a proposal to determine the economic
feasibility of establishing a statewide floodplain management and river channel rehabilitation
program funded separately from the Colorado water conservation board construction fund. The
proposed program would represent a comprehensive approach and source of .fi!.nds for local
gpvernments to better manage mitigation measures, streambanks and channel erosion, loss of
channel conveyance capocity, and loss of wildlife habitat areas.

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COLORADO FLOOD mSTORY
Between July 28 and August 17, 1997, extreme flooding impacted a thirteen-county area of
Colorado as a result of a monsoonal storm system which stalled over the front range area. Point
rainfall amounts of 8.3 inches to 15 inches were recorded. An estimated $200 million in flood
damages resulted in the Fort CollinslLarimer County area, and an additional $50 million in
damages occurred in twelve other counties. Six deaths were attributed to the flooding and the
thirteen-county area received a Presidential Disaster Declaration

Stream and riverine flooding has always been, and remains to be, the greatest potential hazard to
life and property in Colorado. Table I illustrates the most damaging floods that have occurred
throughout the state since the turn of the century. Today, flood prone areas have been identified
in 268 cities and towns and in all of the 63 counties in Colorado. According to CWCB staff,
250,000 people are estimated to now reside in Colorado's 100-year floodplains, with property
valued at over $11 billion. There is a clear need for improved floodplain management efforts to

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