How do I get rid of beaver causing damage to my property?

Beaver are classified as furbearers (WAC 232-12-007). A trapping license and open season are required to trap beaver.
However, the owner, owner’s immediate family, owner’s documented employees, or tenants of real property may shoot (if they are in a designated shooting area) or trap a beaver on that property if the beaver poses a threat to property (RCW 77.36.030, WAC 232-36-051). In such cases, no special trapping permit is necessary for the use of live traps. However, a special trapping permit is required for the use of a Conibear trap in water, a padded leghold trap or a nonstrangling type foot snare trap (RCW 77.15.192, 77.15.194; WAC 232-12-142). There are no exceptions for emergencies and no provisions for verbal approval.
It is unlawful to release a beaver anywhere within the state, other than on the property where it was legally trapped, without a WDFW permit to do so (RCW 77.15.250; WAC 232-12-271).
See WDFW's "Living with Wildlife: Beavers" fact sheet for more information.