The Bonneville Power Administration and the British Columbia Hydro and Power Authority have signed a new long-term agreement to use additional reservoir flow shaping capability on the upper Columbia River in Canada to provide safer flows for protected fish and support power generation. The term of the new Non-Treaty Storage Agreement will extend to September 2024.
“This agreement supports both the environmental and economic health of the Northwest,” said Steve Wright, BPA administrator. “It shapes the release of water to aid migrating salmon and helps produce electric power at times when it is most needed.”
In the 1970s, Canadian authorities constructed Mica Dam to provide 7M acre-feet of water storage as required under the Columbia River Treaty of 1964, plus another 5M acre-feet, termed non-Treaty storage. BPA and BC Hydro have coordinated use of this non-Treaty space under a series of long- and short-term agreements since 1977.
The new pact benefits threatened and endangered fish by providing flexibility for BPA to reduce the flow of water in the spring and then increase the flow of water in the summer when Columbia River flows are low. In the driest water conditions, the agreement allows BPA to release up to 500,000 acre-feet of additional water for fish in the spring. This water is in addition to the flows provided under the Columbia River Treaty.
This agreement’s terms will also benefit juvenile salmon and steelhead when water conditions from heavy spring runoff are high. It allows more flexibility to reduce flows from British Columbia in order to reduce flows and spill at federal dams. This would be used when dissolved gas levels, which are caused by spill and can harm young fish, would exceed state standards at the federal dams on the Columbia.
The power benefits include giving both BPA and BC Hydro the flexibility to move water from periods of lower economic value (periods of energy surplus) into periods of higher economic value.