At the animal shelter here in Olympia, they have "drop boxes" where you can drop off a found pet after hours. I wonder if the Tacoma humane society has the same setup.
You can lookup city of Tacoma and Pierce County dog rescue/pound. All affiliated with the Humane Society.
I took a chance after they were closed and knocked on the back door, one of the staff opened the door and helped me check in the lost pup I found wandering on a busy street.
Contact police (non-emergency phone). Animal control officers have access after business hours.
You can contact an emergency vet they might take it until they open
I would try the back door or call a local animal rescue and ask if they have any ideas such as an emergency foster parent.
Here in Olympia they have drop boxes for you, and a paper to fill out stating where found, etc.
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