Well, made it from Whittier all the way down SGRT on less than one bottle of water, so I chugged it and refilled from the handy little fountain right there at the beach where the trail dead ends. Thanks for the Cerritos park tip, when it gets hotter that will probably be a great spot to rewater.

I rode back on Coyote Creek... unfortunately, it's not really clear where to cross over from the east side to the west (going north), and the west was beautifully paved. The east side was a challenge to my fillings.