You can stay at any rest stop in wa state for up to 24 consecutive hours. Meaning you can stop here overnight. There is an rv dumping station as well as a clean water tank to fill your fresh water holding tank as well. There is no cost for these services. Also, there is a free coffee program run by voulenteers, and vending machines. No public showers, however there are bathrooms though they are not exetremely well maintained unlike others i have visited across the state.
This rest area is too small for overnight stay you can rest there provided its <24 hours I slept there for 5 hours during the day there was no rats either. If you're not trying to live there you should be fine. The SeaTac rest area is close to the airport so if they didn't have a 24 hour max rule the place would be packed with hookers and their johns otherwise
There is no over night stay.Also not sure if rat problem still exists
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