BOARD00718

• Board Meeting Date: 11/25/2002
• Description: Flood Section - Chatfield Reservoir Drought Declaration
• Board Meetings - Doc Type: Memo

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DENVER "VATER

1600 Wesl12th Avenue' Denver, Colorado 80204-3412
Phone [phone]' Fax No. 303-620-6199

Via Fax and E-mail

DATE:

November 20, 2002

TO:

Members of the Colorado Water Conservation Board

Patricia L. Wells, General counseIOa/i/tJ}tilJ:;
Agenda Item 10,b, November 25-26,2002 CWCB Meeting

FROM:

RE:

Item 10.b involves a drought declaration for Chatfield Reservoir that would enable Denver Water
to use its own water in its municipal supply system. For 25 years Denver Water has used its
senior water rights to maintain the recreation pool at Chatfield, making up evaporative losses that
average over 4000 acre feet per year. After this year of exceptional drought, the time has come
for Denver Water to access its water in the recreation pool. The Board memorandum for item
10,b explaining this issue does not accurately portray the issue or the proposals Denver Water
has made, so this memo will attempt to set the record straight. Basically we are asking the
CWCB to declare that "severe and prolonged drought conditions" exist and to allow Denver
Water to use its water under the guidelines we have proposed.

1. Background

Chatfield Reservoir was constructed by the Corps of Engineers as a flood control reservoir. The
Corps constructed the facility with space for a Permanent Pool that fluctuates between 5432 (feet
above mean sea level) and 5423, with an average level of 5426 for recreation purposes. At the
average level of 5426, the amount of water in storage is 20,000 acre feet. The State agreed to
provide water to maintain the Permanent Pool at its own expense, but after several years of
investigation concluded that the only way to maintain the Permanent Pool was to contract with
Denver Water. Denver Water filled the Permanent Pool with its own water rights and has
maintained the 20,000 acre feet in Chatfield since 1979. Denver Water has used its own water
rights to refill the Permanent Pool up to 5426 every year and to make up for evaporation, which
often exceeds 5000 acre feet per year, Evaporation from Chatfield has surpassed 100,000 acre
feet of water over the last 25 years.

2. 1979 Contract

The contract between Denver Water and the State is dated April 3, 1979. Denver Water agreed
to undertake water court proceedings necessary to enable it to use its water rights to maintain the
Permanent Pool in Chatfield.

CONSERVE