Passersby might have done a double-take this week when they saw a man in a wet suit plunging into the Blackwater River in downtown Franklin. It was not a search-and-rescue mission. Rather, a diver for English Construction Co. is removing the underwater foundations of theold bridge over the Blackwater near International Paper Co. Once underwater he drills holes in the concrete foundation. Then he uses a hydraulic “rockcrusher” to split the concrete apart. Bruce Jones, project manager, described the rock crusher as working like slow-motion dynamite. The diver inserts the tip of the crusher into holes in the concrete. Hydraulic pressure spreads the point until the concrete cracks apart. In addition to drilling and cracking the concrete footings, the diver has to use an underwater torch to cut the re-bar so that the pieces of footings can be lifted out of the river.