The decision marks the end of several months of debate concerning BPA’s proposal to reduce the amount of water spilled from turbines at dams in the Columbia and Snake rivers during the months of July and August. Dam managers say they plan to use that water to generate surplus power to sell in California, shaving 1-2% from wholesale rates charged to Northwest utilities with a negligible effect on young fish migrating to the ocean.
The proposal was helped by US agency NOAA Fisheries’ findings that the plans would comply with requirements to protect affected fish species, spelt out in the Endangered Species Act.
While spill is to be cut from the Bonneville, John Day, The Dalles and Ice Harbor dams during the month of August, a set of measures has been drawn up to offset any potential negative impacts including releasing funds for habitat and hatchery projects, the enhancement of flows in the lower Snake river during the month of July, the strengthening of an existing predator control programme and the improvement of rearing conditions for fall Chinook in the Hanford Reach.
Scientists will also continue to investigate the benefits of a new type of spill passage technology at Bonneville dam and the implications of alternative spills at Ice Harbor dam.
BPA said the financial benefits would be passed onto its customers, with expected savings for rate payers to the tune of US$18M–28M this year.
Critics however, claimed that the proposal is nothing more than the latest instance of dam managers putting power production ahead of salmon protection. Business and utility groups contended that BPA is not going far enough, noting that federal officials scaled back an earlier proposal to reduce summertime spill by 55%.
Federal officials expect a negligible effect on the only endangered run of salmon affected by the proposal Snake River fall chinook. Because most of the ocean-bound fish are scooped up and barged below Bonneville dam, federal officials believe cutting off summer spill for the few smolts remaining in the river translates to a loss of only about a dozen of the 2500 adults expected back to spawn in three to five years.
