BOARD00682

• Board Meeting Date: 7/25/2006
• Description: Flood Protection - Consent Agenda - Designation and Approval of 100 Year Floodplain Information
• Board Meetings - Doc Type: Memo

'I

.,
'/

e

STATE OF COLORADO

Colorado Water Conservation Board
Department of Natural Resources
1313 Sherman Street, Room 721
Denver, Colorado 80203
Phone: [phone]
FJ\JC: [phone]
www.cwcb.state.co.us

Bill Owens
Governor

MEMORANDUM

Russell George
Executive Director

TO:

Colorado Water Conservation Board Members

Rod Kuharich
Director

FROM:

Kevin Houck, P.E., Flood Protection Section
Tom Browning, P.E., Chief, Flood Protection Section

Dan McAuIiIl'e
Deputy Director

DATE:

July 6, 2006

SUBJECT: Consent Agenda Items 3a through 3e
July 25-26, 2006 Board Meeting
Designation and Approval of 100-year floodplain information

.

SUMMARY

Consent Agenda Items 2.a through 2.e include five floodplain studies/maps proposed for CWCB
action. Staff is requesting Board designation and approval for these items. A brief summary of the
studies is presented below.

CWCB staff performs technical reviews of floodplain information to assure the Board that the
information is in compliance with the requirements of the CWCB's "Rules and regulations for
Regulatory Floodplains in Colorado". Furthermore, Sections 31-23-301 and 30-28-111, Colorado
Revised Statutes, state that legislative bodies of local jurisdictions may provide zoning regulations for
land uses on or along any storm or floodwater runoff channel or basin only after designation and
approval by the CWCB. In addition, Section 37-60-106(I)(c), Colorado Revised Statutes, directs the
CWCB to designate and approve storm or floodwater runoff channels or basins and to make such
designations available to legislative bodies of local jurisdictions.

The CWCB's designation and approvals greatly assist local communities in meeting the statutory
requirements of the State and the regulatory requirements of the National Flood Insurance Program.
Floodplain information is broadly categorized as detailed or approximate using the following
definitions. Detailed floodplain information means floodplain information prepared using topographic
base maps, hydrologic analyses, and hydraulic calculations to arrive at precise water surface profiles
and floodplain delineations suitable for making land use decisions under statutorily authorized zoning
powers. Approximate floodplain information means floodplain information prepared using a
significantly reduced level of detail to arrive at floodplain (hazard delineation) without water surface