No swimming there, but just down the road is Agua Caliente County Park which does have pools.
Agua Caliente is 4 miles away. Their pools have times they're open and closed. For more info on Agua Caliente (also a San Diego County Park), I'm adding a website http://www.sdparks.org/content/sdparks/en/park-pages/AguaCaliente.html
No place to swim that I saw - pretty dry out there!
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