there really aren't many spots to ride in in long beach. aside from the stadium (salt), everything else is 1-2hrs+ away (6 lakes, 1 (salt) bay). also, most of them are only good at sunrise. the rest of the day, you're screwed. if you can get an invite from someone that rides canyon lake, that would be your best bet. (i'm riding there on sunday

)
san francisco, on the other hand, is about 1hr+ away from the delta. you can get good water any time of the day. also, there are several lakes within driving distance (1-3hrs).