I was just there 2 weeks ago. We stayed in a hotel on the North side of the pier and had planned to have the whole family swim out to the reefs and they snorkel above me while I dove. Depths are around 20-25 in the first couple reef lines. It was too rough that day for them to get out so I went up and down a reef line about at the bouys in 10 feet of water with my son snorkeling above me. So there is a slight reef that close. The better reefs START about where the end of the pier is. There was not alot of boat traffic that day, but there was some. Get a really good visible Dive Flag.
Not only is it pretty good to beach dive there, but you can always get a boat dive there as lots of good dives just a few miles to the North. We could see the boats on the Rodeo and other dive sites offshore within a half mile or so from the beaches. A group from on here went out on the reefs off Pompano the same day I was in LBTS. They said it was like a half hour swim out and they dove 65ft reef wall. They were only a couple miles up the road from us, but I was with the family that day. My 2 oldest start Open Water next week so on my next visit to LBTS I will have my own personal dive buddies!