Washington state law prohibits transport of any visible native and nonnative aquatic animals, plants or other organisms, as well as raw water on any boat, trailer, fishing gear or bait well. If found, law enforcement may stop you and require you to decontaminate your boat or gear.
For non-Washington registered boats to launch in Washington waters, an Aquatic Invasive Species (AIS) Prevention Permit is required. This permit is not required for Washington registered boats, since an AIS prevention fee is applied when the boat is registered through the Department of Licensing.
The AIS Prevention Permit is sold by the Washington Department of Fish and Wildlife (WDFW). The permit is valid for one year from its activation date and is available for purchase online (under the "other" permits tab) or from any of WDFW's authorized license sales providers.