Actually part of Waterfront Park, public restrooms are at the east end of the boardwalk in a new community building known as the Harbormaster's Office. A little off the boardwalk, but still almost within the park, is a larger public-restroom building which is at the northwestern corner, between the parking lot and Merrimack Street. Those are the only ones I know of that are at or near the park.

There is a public parking lot and street parking although you may have to circle around for street parking. In the summer months it is very busy but fall is a beautiful time to visit.