Bridge and underground utility debris are readily available, but makes a reef that is not as dramatic as a ship. And construction debris on the bottom of the ocean doesn’t look any better than it does on land. The fish don’t seem to care as long as long as there are lots of nooks and crannies to hide in, but many divers would rather see a more natural looking reef. Since concrete sinks, the permit only requires a 250 foot setback from live reef, making site options much more plentiful.
The biggest challenge with the construction material approach is finding a 3+ acre waterfront “lay-down” yard to store 5,000+ tons of donated concrete while it is being accumulated for loading on a barge and offshore placement.
Inland sites are available, but that requires moving the material twice and the costs become prohibitive. A dump truck can move an average of 15 tons of concrete per load at a cost of about $400/ load. Moving 5000 tons of concrete requires about 330 dump truck loads and would cost about $13,000. Moving the material twice is hard to justify. We continue to work to find a local waterfront lay-down yard where materials could be stored and loaded directly onto barges.