BOARD01017

• Board Meeting Date: 1/25/2005
• Description: Flood Section - Chatfield Reservoir Reallocation Study Progress Reports
• Board Meetings - Doc Type: Memo

,."

.'

STATE OF COLORADO

Colorado Water Conservation Board

Department of Natural Resources
1313 Sherman Street Room 721
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
www.cwcb.state.co.us

Bill Owens
Governor

MEMORANDUM

Russell George
Executive Director

TO:
FROM:
DATE:
SUBJECT:

Colorado Water Conservation Board Members
Larry Lang, P.E., Chief, Flood Protection Section
January 1"0, 2005
Agenda Item 7a -7d, January 25-26, 2005 Board Meeting--
Chatfield Reservoir Reallocation Study Progress Reports

Rod Kuharkh
eweB Director

Dan McAuliffe
Deputy Director

)

Introduction
The Chatfield Reservoir Reallocation Study Progress Reports are presented in the four agenda items, 7a. tlrrough
7d. that represent the study purposes and CWCB interests. The purposes and interests for the items are:
7 a. Update on the project performance tasks, schedules, and budget
Th. Acceptance of the Water Users Subcommittee's allocation recommendation for the 20,600 ac-ft
additional Chatfield Water Supply Pool
7c. Creation of the Chatfield Reallocation CoIp'S FCSA Study Fund
7 d. Presentation by the Corps on the Environmental Impact Statement Scoping and Chatfield
Antecedent Flood Study

Background Information

The Colorado Water Conservation Board (CWCB) on September 2, 1999 contracted with the Corps of
Engineers (Corps) to be the project sponsor for the Chatfield, Cheny Creek and Bear Creek Reservoir
Reallocation Study Agreement. The agreement was for the accomplishment of the Chatfield Reservoir
Feasibility Reallocation Study to determine the feasibility of additional water supply storage in the reservoir.

The current water supply storage level and volume in the reservoir are at 5432 M.S.L and 27,000 acre-feet.

At our May 5, 2004 Chatfield progress meeting, the Corps presented proposals about hqw to increase and
reallocate up 20,600 acre-feet of additional water supply storage from flood control and spillway surcharge
storage that would be in compliance with the water control manual. This value of20,600 acre-feet is the one that
the CWCB is using for the additional water supply space allocation negotiations with the interested water users.
The Corps has requested that the CWCB perform this study task. It is also the upper limit for the environmental
and project mitigation activities, which may occur for an enlargement of the existing conservation water storage
to an elevation of 5,444 M.S.L.

Flood Protection. Water Supply Planning and Finance. Stream and Lake Protection
Water Supply Protection. Conservation and Drought Plamring