News Release
Release Number: | 00-007 |
Dated: | 1/26/2000 |
Contact: | Public Affairs Office, 503-808-4510 |
Portland — The Portland District, U.S. Army Corps of Engineers, has nearly completed the first phase of a possible two-phase study of drawdown options for John Day Dam on the Columbia River.
The John Day Drawdown Phase I Study Draft Report will be issued by the end of this month. Two meetings will be held specifically to discuss only the Drawdown Study: at the Desert River Inn, 705 Willamette Avenue, Umatilla, Ore., at 7 p.m., Wednesday, Feb. 16; and at the Goldendale Primary School Cafeteria, 840 S. Shuster, Goldendale, Wash., at 7 p.m., Thursday, Feb. 24.
Study team members also will participate in a series of public meetings being held to share information with the public about a variety of fish recovery topics. Those subjects include: the Lower Snake River Juvenile Salmon Migration Feasibility Study and Environmental Impact Statement; the Federal Caucus’ All-H Paper; the John Day Drawdown Study; and related studies.
In October 1998, Congress directed the Corps to study John Day drawdown and appropriated $3.7 million for the first phase of that Study. Congressional direction limited the first phase to two options for lowering, or drawing down, the reservoir: "spillway crest" and "natural river level."
"As we began this study," said Stuart Stanger, project manager, "our goal was to gather enough facts on impacts and benefits that we could make one of two recommendations to Congress. We wanted to either be able to recommend dropping all further study of lowering the John Day reservoir off the regional agenda because of what we learned, or recommend further study of drawdown, which would include evaluating an expanded list of drawdown alternatives.
"The Corps is the fact-finding agency. Our recommendation is based on all the information we have gathered," Stanger said. "We assessed potential biological benefits and economic costs. Our biological studies show that drawdown would contribute little to the survival and recovery of listed Snake River fish. On the positive side, it would reduce migration time from McNary to John Day dams by one or two days, and could increase numbers of upper Columbia River spring chinook. On the downside, however," Stanger said, "there is a significant risk in modifying habitat used by the healthy Upriver Bright fall chinook, and drawdown would change that habitat.
"Based on those biological findings, and economic assessments, we believe that no further study is necessary to allow Congress and the Region to make a decision regarding drawdown of the John Day reservoir, or removal of the John Day Dam. This is our draft recommendation. It could change after we consider additional information gathered during the February-March 2000 public comment period. We plan to forward our final report to Congress in July 2000."
John Day Dam, which spans the Columbia River from Washington to Oregon 215 miles upstream from the Pacific Ocean, creates a 76-mile-long reservoir (Lake Umatilla). Reservoirs slow river current and create slack water, thus slowing juvenile fish migration through the river system, and Lake Umatilla is the longest reservoir on the lower Columbia River.
Lowering reservoirs behind the dams to levels that are substantially below the normal operating range is called drawdown. Lower water levels decrease reservoir width and depth, which increases water velocity. Increased water velocity could move juvenile fish through the reservoir more quickly, thus mimicking historically faster journeys downriver. This may increase survival rates.
In this first phase, the Corps identified the impacts of both options: spillway crest and natural river. They have evaluated biological, social, and economic benefits and costs, plus potential physical impacts of each.
The Corps’ Report details impacts on irrigation, fisheries, wildlife, flood damage reduction, hydropower production, navigation, cultural resources, recreational activities and water supply, as well as hydraulics and hydrology affects, and associated structural changes at John Day Dam.
Normal reservoir operating level is elevation 265 (normal pool). At spillway crest drawdown (about 50 feet lower), fish passage systems at John Day Dam would have to be modified and there would be effects on other users of the river. At natural river (about 100 feet lower), the river could be rerouted to bypass John Day Dam or the dam could be breached. There would be dramatic effects on navigation, irrigation, recreation, hydropower production, cultural resources and water supplies.
The second phase, if directed by Congress, would evaluate the costs, benefits and physical impacts of a wide range of alternatives, including potential physical modifications to the dam. That phase would include an Environmental Impact Statement (EIS) and related National Environmental Policy Act (NEPA) coordination. Public comments are part of those processes.
Neither the first nor second phases of this study will include actual physical modifications at the John Day Dam.