OPINION: Dams aren't the cause for declining numbers of fish...

In 1965, NMFS began trucking smolts collected at Ice Harbor Dam to below Bonneville Dam. As bypass facilities were developed, transportation was approved by the regional fishery agencies. Objectives were: (1) to avoid turbine mortality at downstream dams, (2) to avoid predators in downstream reservoirs, and (3) to offset smolt migration delays caused by the series of eight dams and reservoirs. Since 1976, the Corps has acquired fish transport trucks that can transport up to 17,000 smolts per trip. When 1977 threatened to be a severe drought year, the Corps acquired two military surplus barges and modified them to transport up to 230,000 smolts at a time. Because improvements for reducing the TDG above did not cover the peak floods, a fourth objective of transport was added. New barges were equipped with dissolved gas-stripping chambers that reduce TDG levels back to normal. In the early 1980s, the Corps acquired specially two 500,000-smolt fish barges. Four more barges capable of carrying up to 750,000 smolts each later were added. Fish barge tows can leave Lower Granite Dam daily, pick up fish barges loaded at Lower Monumental and Little Goose dams, and deliver more than 1 million smolts per trip below Bonneville Dam 36 hours later. Transport has consistently provided 98% smolt survival compared to current NMFS estimates of 40% to 60% in-river survival with mass spill. Compensation for fish losses caused by the lower Snake River dams began in the late 1970s with the Corps collaborating with the fishery agencies to develop 11 hatcheries costing about $300 million. The Snake River Basin hatcheries provide up to 25 million smolts, about half of which survive to Lower Granite Dam. The largest single 24-hour collection at Lower Granite was more than 1 million hatchery and wild smolts before mass spill. In 2020, fishery interests convinced a federal judge to order mass spill to save the fish. The opposite has happened. Mass spill minimizes power generation and reduces smolt collection more than 90%. With the majority subject to in-river mortality, only half of the smolts now reach the ocean. Adult returns are reduced by harvest in the ocean from Alaska to Oregon. Then salmon must swim upstream through 400 miles of river with 125% TDG and delays by confusing flows at dam fishway entrances. Adults return to hatcheries and spawning grounds with TDG trauma symptoms. Spring/summer chinook and steelhead must survive months in freshwater before spawning. Fish management agencies blame the dams for reducing smolt-to-adult returns. Ocean, lower river and Idaho river harvests are reduced or canceled because the judge and agencies require improper use of fish protective measures at the dams, not because the dams are the base cause. McKern was a fish and wildlife biologist for the Walla Walla District, Corps of Engineers, a consultant on Columbia Basin fish passage issues, and is currently an adviser to the Citizens for the Preservation of Fish and Dams, Inc.