San Francisco Evening Open Swim?

Hi there, I just moved to San Francisco from the east coast and want to re-start my swimming up here. I miss my old swim center and can't seem to find the right one in the city. I'm not sure I'm ready to join a master's program but really want to swim regularly. I live in Cole Valley right near the N-Judah line and would like to find a pool I don't have to drive to since parking is a bit of a bear in my neighborhood. If anyone has any thoughts I'd be really grateful to hear them. I'm longing for the pool...