The Artificial Reef Program used four types of obsolete Army armored vehicles as artificial reef materials off the New Jersey coast. These were cleaned at local military bases, loaded onto barges for transport, and pushed off at their final destination. Once the Army had disposed of its excess inventory, the program ceased, around 1999. The Artificial Reef Program has sunk almost 400 tanks altogether, far too many to list them here in this website.
All manner of concrete, steel, and stone rubble from dredging, demolition projects, and other construction is used as artificial reef materials. This material is generally available at very low cost or free from construction companies who are more than happy to get rid of it. Transportation costs determine where this material is used by the Reef Program.
Long Island Sound averages 60 ft in depth, with the greatest depth of over 300 ft at the eastern end. Tidal effects are strongest at the narrow western end, where all the inrushing water flow piles up and makes tidal variations of up to 7 ft. Strong tidal currents are also prevalent, and visibility tends to be poorer than the open ocean, especially at depth.