No problem with any of our SoCal beaches that I'm aware of.....be it State or local. ...
Cudamark, most of the CA coastline beaches are administered by the state. As opposed to county, or city, or federal. And so long as any md'r can remember, there is no problem on state-of-CA run beaches. They've simply, quite frankly, been md'd since the dawn of detector (I know some guys who were detecting them in the mid 1960s even). So ... who's to argue with that, eh ?
However, one day, in the early 2000's, a buddy of mine was md'ing at Seacliff State beach (south of Santa Cruz). It *just so happened* that a state archaeologist was visiting from Sacramento, getting ready to give a lecture at the little beach-side museum that's right there. And it *just so happened* that ... as he was walking from his car to the musuem, that he happened to glance out to the beach. And he *just so happened* to see my friend detecting. He detoured from his walk path, walked down on to the beach, and READ MY FRIEND THE RIOT ACT.
At first, my friend was taken back, and thought this was all some big mistake. Because, as you know you can detect state beaches, no problem. Right ? The more he listened to the fellow rant, he became aware of the guy being a state archie. And when my friend tried to object and say "since when?" and "where is that written?", the guy pointed over at the 1920's wharf & cement ship, and started rambling about "historic" or "cultural" or some such nonsense.
This is actually sort of laughable, because Seacliff is amongst the NEWEST of the CA beaches for public access/use. The road leading down from the cliffs didn't even exist till the 1920s. So the 2 of them squared off and argued a bit, with neither one of them backing down. The archie stormed off, threatening that he was going to get a ranger to come boot or ticket him or something.
As soon as the archie was gone, my friend realized he didn't want to be around, when and if that archie returned with a ranger (although it could have been an empty threat, he wasn't sure). So .... after a few more minutes, he decided to pack it in and call it a day.
He reported this encounter on a local CA md'ing forum. And ... as can be expected, we all laughed KNOWING that "certainly this archie is mistaken . Because everyone knows you can detect state of CA beaches, right ? So this would simply be a matter of looking up the law, and then "putting this guy in his place", right ?
But the more we looked into the minutia ..... the more we realized that ... uh .... we'd better leave 'good enough alone'. Because there is, in fact, cultural heritage wording in the CA parks wording (as there probably is in all 50 states for that matter). And ... afterall, it's *possible* you might find something old, right ? So rather than think we were going to "clarify this" or "set this guy straight", it was decided to do absolutely nothing. Odds are, that guy went back to Sacramento, and is not going to be at the beach again, nor will likely see an md'r, etc.... So why swat a hornet's nest ? If no one else, besides a single purist archie, in the entire state "cares less", why oh why seek to 'clarify' anything ?
That was 15 yrs. ago. And still, to this day, you can detect state of CA beaches till you're blue in the face. Moral of the story ? Sometimes it's better NOT to make waves and ask silly questions.