This pier runs behind the boathouse at Aquatic Park in San Francisco. Historically - this facility has been part of The Boy Scouts of America. The group's anti-gay stance has had them out-of-favor in this city for some while - and the lack of maintenance here suggests that perhaps that knot has slipped.
If anyone knows what the status of this place is - please let me know.
Meanwhile - I love the patterns and colors in this image. Enjoy.