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Two Years Late, Corps Announces Its "99 Decision," Says Dams Will Stay by Bill Rudolph NW Fishletter, December 20, 2001

The Corps of Engineers has finally announced its preferred alternative for future operation of the lower Snake dams, marking the conclusion of a process that began in the 1995 BiOp that outlined a course designed to culminate in "the 1999 decision" on drawdown to help ESA-listed fish.

Six years and over $20 million later, the Corps--to no one's surprise--has announced that it prefers to make major system improvements at the four dams, rather than tear them out. The drastic breaching alternative came to light after an interim review found that partial-year drawdowns of reservoirs behind the dams would cost more and probably help fish less than simply breaching them and paying the economic price.

By 1999, the Corps had narrowed the range of alternatives to three others besides breaching: existing condition, maximum fish transport, and the major system improvements. Last year, 8,700 people attended meeting throughout the Northwest to discuss the options. The Corps collected 230,000 written comments before it was all over.

By then, NMFS had weighed in with its biological analysis that took issue with the earlier PATH recommendations that picked breaching over other options. But NMFS, using the most recent PIT-tag data, found that fish survival through the hydro system was higher than PATH scientists had estimated. However, critical uncertainties, like the question of comparative survivals of barged fish versus inriver migrants, kept the agency from making a direct recommendation one way or the other.

The latest NMFS hydro BiOp called for resolution of these questions and for dam breaching studies to begin if listed fish runs don't improve. But it also concluded that even if survival through the current hydro system were 100 percent, return rates would be too low to maintain the runs, so the BiOp recommended extensive offsite mitigation efforts to help fish--especially in the first year of their life. Since then, return rates have vastly improved for the time being, largely due to improvements in ocean conditions.

Though NMFS said it was unlikely that fish survival through the hydro system could improve by much, the Corps says it will improve the coordination and implementation of spill, flow augmentation and juvenile fish transportation, along with both near- and long-term structural improvements like better turbines, removable spillway weirs and surface bypass and collection structures.