FLOOD08539

• County: Statewide
• Basin: Statewide
• Title: Floodplain Designations and Approvals
• Date: 2/23/1998
• Prepared For: State of Colorado
• Prepared By: CWCB
• Floodplain - Doc Type: Community File

RECOMMENDA nON:

PLAN I - Using this plan, the existing staff would address one management group at a time
except for Group No.5 as shown in Exhibit A. Groups I and II are ready for review using
existing resources with completion by January, 1995. For Groups III and IV the existing
resources will be greatly enhanced if the Board can allot $25,000 for the preparation of an
"Approximate Hydrology Handbook". The handbook would be prepared from the
hydrologic information presently in the existing in the 349 designated floodplain reports.
Through a contract with a consultant, the Board would prepare hydrologic drainage area vs
discharge equations/curves using a multiple Regression Program. Homogenous Regional
Basins will be grouped and hydrologic design equations/curves will be computed using
existing data. The Board staff will use these design equations/curves for unstudied stream
reaches to determine stream hydrology. This streamlined procedure would greatly reduce
the technical review time for Groups III and IV and will provide Colorado Communities
with discharges which are reasonable for floodplain management purposes. This procedure
will fulfill the intent of Rule 6.B.l of the Boards - "Rules and Regulations" for floodplain
designations. Group V report will include information which is received after December
31,1993. The intent will be to review and make a recommendation for CWCB designation
at the next, regularly scheduled CWCB meeting. Under Plan 1, the floodplain information
backlog would be complet~d by July 1998 for the information as presented in Exhibit C.

PLAN II - Using this plan, the existing staff would address management groups I, II, Part
of ill, and V. The board would contract a large portion of management groups ill and IV
to a consultant A consultant would perform the technical reviews, under the direction of
the board staff. For Groups ill and IV, it would be necessary to prepare the "Approximate
Hydrology Handbook" as proposed in Plan I. The Handbook would be designed and
prepared under the same specifications as for Plan I. The handbook contract is estimated
at $25,000.00.

Should it be the decision of the Board to contract the reviews for Groups ill and IV
to a consultant, the contract fee is estimated $170,000.00 using 2584 man-hours for Group
ill and 830 man-hours for Group IV at a rate of $50.00 per hour. Under Plan II, the
floodplain information backlog would be completed by January 1996 for the information as
presented in Exhibit C.

Under Plan I or II, the completion of the floodplain information review and
designations backlog is obviously a major Section task. It appears that time verus dollars
is the major consideration for completing the task.

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