There is the risk that if Chinook are passed upstream at Tumwater Falls that they would establish a "wild" run. The Squaxins were (at least a decade or two ago) afraid that if there was a wild run of Chinook in the Deschutes that NOAA would want them listed and this would constrain the fishery for the hatchery Chinook. A few Chinook used to be passed up to provide a sport fishery. I think all the coho, even though they are an exotic invasive in the Deschutes, are passed upstream. For some undetermined reason, that run has crashed along with most deep South Sound fish that have yearling or older smolts.