They might only be open when one of the pavilions is rented. I'm not sure. There's often a park attendant in a golf cart on duty. They would know.
In season, approximately April to October, the restrooms are open from approximately 7 am until closing which coincides approximately with sunset. Off season, there is a port-a-potty near the trail and parking lot off Willowbrook Road.
I thought they were open all the time. I've seen the grounds keepers cleaning and locking them up around closing time a few times.
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