WSDOT owns, operates, and maintains 43 developed safety rest areas (28 on interstate highways and 15 on non-interstate highways). In the safety rest areas, WSDOT manages 85 buildings, 566 acres of land, 30 on-site public drinking water systems, and 37 on-site sewage pre-treatment/treatment systems.
Safety rest areas on the interstate system typically serve one direction of travel such as north-bound (NB) or south-bound (SB). Non-interstate safety rest areas typically serve traffic from both directions and are identified as being multi-directional (MD)
See the Safety Rest Area Inventory table below for more information.

Map of Washington's Safety Rest Areas
View location information.

Source: WSDOT Maintenance and Operations Division - also available in WSDOT's Gray Notebook for March 31, 2004