More so than any other trout river in our region, the Williamson is known to produce truly trophy sized fish. A large part of this is because it is a tributary to Klamath Lake. As the lake heats up throughout the summer, those brutish fish will filter into the river in pods from June-August. Fishing on the Williamson corresponds with the lake temps rising. Often the early season over here can be a bit slow. But by mid-July there are usually good numbers of trout present throughout the river.