Closer to home, ice age megafloods affected Lake Tahoe, flowing out through the Truckee River over the Reno-Sparks area. Evidence has shown Lake Tahoe rose between 90 and 600 feet at various times due to glacial dams.
And yet closer, although I can't find a reference, I was told by a friend once of an ice dam break on the south fork of the Kaweah River near Three Rivers that uprooted giant sequoias and washed them miles downstream.