Tacoma Power of the US has offered to build a fish ladder over the 72m high Mayfield dam on the Cowlitz river if fish advocates agree to it under its operating licence. The Washington-based utility made the offer, qualifying it as a proposal during a meeting of relicensing participants. The proposal, which could cost as much as US$100M, brightened prospects of a licence many parties could support.
Tacoma’s existing licence for the dam and hydro facility expires on 31 December 2001. The 160MW Mayfield dam was constructed in 1968 and has no facilities for fish passage. A fish ladder would allow fish to swim upstream and spawn without human intervention, at least in the Tilton river and other Mayfield tributaries. Cowlitz and Yakama tribal officials and citizen fish advocates have lobbied hard for fish ladders over Mayfield and Mossyrock dams to allow salmon and steelhead to spawn naturally. The construction of a fish ladder was not offered for the 112m high Mossyrock dam (300MW), due to its height and difficulty of access to the site. While Tacoma officials had not specifically expressed a preference, many assumed the utility would lobby for expanded trapping and hauling of fish around the dams, a plan state and federal biologists have supported as most likely to succeed.
At Tacoma’s Cushman hydroelectric operation in Mason County, the utility has rejected the federal licence order that itself forecasts first-year losses of US$2.5M for the utility. Tacoma officials have appealed and sued in federal court, threatening to abandon the dam. The 124MW project on the Skokomish river was constructed in the 1920s. Tacoma first applied to relicense the project over 25 years ago.