The following is from a Washington State Patrol press release:

The Washington State Patrol is adding extra patrols for the 4th of July holiday by dedicating troopers to patrol interstates and state routes.  Troopers will enforce all traffic laws with special attention to speeding, aggressive driving, impaired driving, seatbelt and child restraint violations.

Statewide in 2012, troopers arrested 484 impaired drivers, issued 8,565 speeding infractions, and 1,303 seatbelt and child restraint infractions over the 4th of July weekend.

The agency is asking motorists to take time to prepare for safe travel, and stock up on supplies such as a flashlight with extra batteries, water and food, a first aid kit and an emergency communication device.  The agency also recommended motorists check their tire pressure before traveling and pack tools such as a working jack in the event of a flat tire.

When traveling, expect delays due to heavier than usual traffic volumes.  Leave yourself plenty of time to make it your destination.  If you consume alcoholic beverages, call a friend, taxi, or use a designated driver.