Firefighters battled flames in a brush fire near Cowiche Wednesday afternoon that burned about 20 acres near Sunset Way and Cowiche Mill Road.  At least one home was threatened by the blaze. The fire burned through sagebrush for several hours before it was contained.  Firefighters were helped by the use of a helicopter from the training center and the department of natural resources to drop water on the flames.  No injuries were reported.  Several different fire agencies from throughout the valley helped douse the flames.