Park open from sunrise to sunset (however, it appears that during the summer, park closes at 8 PM).
When I was placing this cache, the song, "Under the Boardwalk" popped into my head. For those of you not familiar, here's a link to Youtube with that famous song by The Drifters:
Under The Boardwalk
There is a boardwalk here that goes out over part of the San Antonio River, and is part of Acequia Park. You'll often see people setup here to go fishing. It's a beautiful little spot, one just calling for a cache! Container is small, but filled with SWAG for the kiddos.