This project completed fish passage improvements to 1,344 feet of the two mile-long Mill Creek flood control channel. Modifications of the concrete channel provided depth and velocity conditions favorable to passage of Mid-Columbia summer steelhead, bull trout, and spring Chinook. Under pre-project conditions, returning adults encountered velocities that were too high for too long of a distance, without any resting opportunities. To improve passage, part of the existing channel was cut and removed. Pre-cast "roughness panels" replaced the removed concrete. The roughness panels have block-shaped projections which create friction in the water, slowing it to a velocity that the fish can swim for the full distance of the project. Resting pools were also added as an additional measure. During low flow, under pre-project conditions, baffles in the channel created hydraulic conditions that were a barrier to juveniles. The baffles were removed and replaced with new baffles that were sized and spaced to provide volitional passage for juveniles.