I thought it was illegal to shoot into, over a body of water. 

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Once a few years ago, while diving under a bridge in the Tennessee River, my dive buddy & me were just having a good ol time lookin for bottles & such...during the dive we both started hearing concussive sounds but didn't know what the heck it was...after we decided to end the dive, we continued with our plan. to swim along the bottom back down current to our exit site , a clear place along the bank...we got out and as we were walking up to our tarp, a State Trooper car pulled in behind ours... he said that it's a good thing that we'd towed a diverdown flag along, or else the guy that had called him wouldn't have known that the 4 teenagers he seen throwing boulders & rocks in the water off the bridge were endangering anyone... so....there ya go...