Skamania summer run stock are Washougal and Wind River origin and return primarily as 2-salt adults. Kalama had an endemic native summer steelhead stock that also returned mainly as 2-salt adults, based on stories I heard of the pre-hatchery program days. I wouldn't expect much difference in run timing.

The reason early return summer steelhead were common was because a good share of the hatchery broodstock was taken from early returning adults and because smolt plants and adult returns were much larger. When the shape of the return curve remains the same, but is increased in magnitude, there are more fish in the river during all time periods, early, mid-season, and late season.