For a little local clarification; the law that is linked specifically covers state parks, not state owned public lands in general. The ARAP law that was listed is Federal law and pertains specifically to federal lands, e.g. the Francis Marion.
Municipalities can and have set their own laws. The city of Charleston specifically forbids metal detecting in city parks and/or city property. They also claim domain out 11 feet BELOW the low mean tide level (basically, 11 feet into the water when its at it's lowest point meaning that's legally off limits too). Also keep in mind that the city of Charleston occupies more than just the peninsula area. I think they primarily get their panties in a bunch over people detecting in that area, but the law covers the entire city. SC law also lays claim to ALL waterways within the state for finds. Limited numbers of permits are available for recovering stuff in said waterways (lakes, rivers, creeks, etc...), but those permits are pretty heavily regulated.
A good reference to check the various local and county codes is Municode.com. They list most places here in the Lowcountry. For state laws go to scstatehouse.gov/code/statmast.php . With those two sites you can pretty much cover laws for the entire state!
I do agree 100% permissions in the area have gotten harder and harder to obtain. Not only for the issues Dug previously mentioned, but because some people who had permissions abused them thereby ruining it for everyone! One example; a very close friend is a service planner for one of the local power companies (won't say which, but they cover areas you wouldn't think they'd be in....and all of them have great potential spots!). He was east of the Cooper on an 18th century plantation and was talking with the owner. He has a standing request from me to get an introduction to property owners if the chance arises so I can personally talk with them about permission. He mentioned detecting to the owner who told him he used to allow people to detect there. At first it was the guy who asked and he'd occasionally bring a friend or two, no problem. He stated that not long afterwards though groups of people were coming and going at all times of the day, sometimes with the guy and sometimes without. They'd run all over his property and he didn't know any of them. Because of the larger groups that began coming and having no basic respect for the fact this was the man's home, he pulled the permission from the guy and now refuses to grant one to anyone!
Most of us here in the Lowcountry suffer and struggle for at least one or two good permissions we can hunt freely!
