The Washington State Department of Ecology is beginning preparation of a Supplemental Environmental Impact Statement for the Lake Roosevelt Incremental Storage Releases Project -- formerly called Lake Roosevelt Drawdown Project.

This project is being undertaken as part of the Columbia River Basin Water Management Program.

The Supplemental EIS will provide a more thorough evaluation of impacts associated with additional releases of stored water from Lake Roosevelt than was presented in a "Programmatic" EIS.

The project involves a proposal to divert up to an additional 132,500 acre-feet of water stored in Lake Roosevelt under the Bureau of Reclamation's 1938 water storage right. The project includes withdrawals that would occur every year as well as withdrawals that would occur only during drought years. On an annual basis, 82,500 acre-feet of water would be released from storage for the following purposes:

-- 30,000 acre-feet of water for replacement of ground water used for existing irrigated agriculture in the Odessa Subarea,

-- 27,500 acre-feet for in-stream flow enhancement downstream of Grand Coulee Dam, and

-- 25,000 acre-feet for municipal and industrial use along the Columbia River.

In drought years, an additional 50,000 acre-feet would be released and apportioned as follows:

-- 33,000 acre-feet of water for existing, interruptible water right holders along the Columbia River mainstem, and

-- 17,000 acre feet of storage for in-stream flow enhancement downstream of Grand Coulee Dam.

The action being considered by Ecology is the issuance of water rights to implement the project.

The Supplemental EIS will evaluate the degree to which the incremental releases from Lake Roosevelt will add to or reduce existing impacts associated with reservoir operations including:

-- Impacts on downstream stream flows below Grand Coulee Dam;

-- Air quality and environmental health impacts associated with heavy metal contaminated lake sediments;

-- Water quality impacts, including temperature and Total Dissolved Gases;

-- Changes to surface and ground water flows;

-- Impacts to tribal water rights;

-- Potential for bank sloughing;

-- Effects on resident fisheries in Lake Roosevelt;

-- Effects on wildlife habitat and wetlands adjacent to Lake Roosevelt;

-- Stranding of boat ramps, marinas, and swimming areas as well as economic impacts of decreased recreational opportunities;

-- Impacts to hydropower generation; and

-- Effects on cultural resources, including potential for exposure or resources and vandalism.

The Supplemental EIS will evaluate a number of different scenarios regarding the timing of the releases. It will also evaluate policy issues concerning apportionment of incremental releases for municipal and industrial users as well as interruptible water right holders. Policy choices will be evaluated for determining eligibility to receive water and for allocating water among eligible recipients.

The deadline for submitting comments is Jan. 5, 2008.

A copy of the official public notice and other information about incremental storage releases at Lake Roosevelt are available at the Department of Ecology's website, http://www.ecy.wa.gov/programs/wr/cwp/cr_lkroos.html#publiccomment