CK,

No, Tacoma is not obligated to restore sockeye and chum salmon on the Cowlitz. The reason I am aware of is that Tacoma's project isn't the proximate cause of losses of Cowlitz sockeye and chum salmon. Let's take this stepwise.

Sockeye that occur in the Cowlitz are from three probable sources that I can think of. First, there may be an endemic run of Cowlitz sockeye, but there are no records of any persistant historic run that I am aware of. Second, sockeye in the Cowlitz might be strays from Columbia River tributaries that do support sockeye runs. Third, sockeye in the Cowlitz might be strays from Columbia River tributaries that are stocked with kokanee in their reservoirs that became anadromous and migrated to and returned from the ocean. In any of these cases, there is no project impact to a Cowlitz fishery resource that Tacoma would be required to mitigate.

Historically, some chum salmon apparently migrated and spawned upstream of Mayfield Dam, but the preponderance of the run spawned in the lower Cowlitz. The historic chum habitat upstream of Mayfield is now inundated by reservoirs and is no longer suitable for chum salmon for starters. Never mind that chum salmon are notoriously resistant to using fish ladders. The chum salmon that formerly spawned in the lower Cowlitz have more than likely been largely lost due to impacts other than Tacoma's project. The primary cause is loss of habitat due to diking the lower river, directly causing the loss of side channels, a habitat type that is preferred by chum. In my opinion, chum salmon recovery will be nearly impossible in the lower Cowlitz - and perhaps the lower Columbia River - as long as huge numbers of hatchery coho are released into the respective systems, unless hatchery coho are held until June 1 for release.

In north Puget Sound, chum production, and pink salmon for that matter, was inversely correlated to the numbers of hatchery coho released. Studies have shown that hatchery coho smolts, which are reared to a larger size than their wild brethren, prey on juvenile pink and chum salmon.

The vast majority of coho in the Columbia River system are of hatchery origin, and the development of those programs, along with the loss of the best chum habitats, roughly correlate with the decline of chum.

The upshot is that Tacoma shares some fraction of the responsibility for loss of Cowlitz coho, and perhaps moreso because the Cowlitz hatchery produces a large % of lower Columbia coho. Tacoma is obligated to acquire some lower Cowlitz side channel habitat for salmon recovery. That could include chum salmon habitat recovery if the fishery agencies so wish.

That's my two (s)cents.

Sincerely,

Salmo g.