Rising temperatures and pollution are driving a global coral crisis: a 2020 report found 14% of reefs lost between 2009–2018, and a recent bleaching event affected about 84% of reefs. Artificial reefs—sunken ships, concrete modules, mineral-accretion systems and retired oil platforms—offer solid surfaces for coral to recolonize and can support fisheries and coastal protection valued at nearly $30 billion annually. While early projects sometimes used unsuitable materials, modern programs are more carefully engineered; the U.S. has converted over 600 oil platforms into habitat. Properly designed artificial reefs are a useful restoration tool but cannot replace efforts to stop warming and pollution.
Artificial Reefs: Can Sunken Ships and Rigs Help Save Dying Coral Ecosystems?
Rising temperatures and pollution are driving a global coral crisis: a 2020 report found 14% of reefs lost between 2009–2018, and a recent bleaching event affected about 84% of reefs. Artificial reefs—sunken ships, concrete modules, mineral-accretion systems and retired oil platforms—offer solid surfaces for coral to recolonize and can support fisheries and coastal protection valued at nearly $30 billion annually. While early projects sometimes used unsuitable materials, modern programs are more carefully engineered; the U.S. has converted over 600 oil platforms into habitat. Properly designed artificial reefs are a useful restoration tool but cannot replace efforts to stop warming and pollution.
11:10 PM, 11/11/2025Environment
Overview
Pollution and rising sea surface temperatures are devastating coral reefs worldwide. A 2020 Global Coral Reef Monitoring Network report found that about 14% of the world's coral reefs were lost between 2009 and 2018, and the most recent mass-bleaching event affected roughly 84% of reefs—far more than previous events in 1998, 2010 and 2014. Coral reefs support roughly 25% of marine life and more than 4,000 fish species, so these losses dramatically impact ocean biodiversity.
What is an artificial reef?
An artificial reef is a man-made structure deliberately placed on the seafloor to provide hard surfaces and vertical relief where marine organisms—especially corals, sponges and fish—can attach, shelter and reproduce. Common materials include intentionally sunk ships, concrete modules, reinforced steel structures, mineral-accretion systems such as electrified Biorock, and repurposed oil platforms.
How artificial reefs work
Think of scenes from film where divers swim through a shipwreck teeming with life: that is the basic idea. Large steel structures provide extensive surface area and are heavy enough to resist currents and storms, making them ideal reef substrates. For example, the aircraft carrier USS Oriskany (about 32,000 tons) was intentionally sunk about 24 miles off Florida in 2006 and is one of the world’s largest artificial-reef ships.
Benefits: ecological and economic
When well designed and sited, artificial reefs can:
- Provide habitat and surfaces for coral and other organisms to colonize.
- Support local fisheries and recreational diving, boosting coastal economies.
- Enhance coastal protection by encouraging reef growth that dissipates wave energy.
The U.S. Environmental Protection Agency estimates reefs generate nearly $30 billion in annual economic value through fisheries, tourism and coastal protection. Even branches of the U.S. military have investigated novel materials—such as self-healing concrete—to protect shorelines and installations from storm surge.
Limits and risks
Artificial reefs are not a cure for the root causes of coral decline: warming oceans and pollution. Early reef projects were sometimes careless—using tires, cinder blocks or toxic industrial scrap that offered poor habitat or harmed marine life. Those practices have largely been abandoned as reef construction has professionalized, but risks remain. Poorly sited or unstable structures can shift in storms, and artificial reefs can inadvertently concentrate fishing pressure if not managed.
History and notable programs
People have been creating artificial reefs for centuries—Japanese fishermen were building them by the 1700s. In the United States, Hawai'i installed artificial shelters in the 1960s, and California launched a formal program in 1985. Since the 1980s, more than 600 decommissioned oil platforms on the U.S. outer continental shelf have been repurposed or left in place to act as reef habitat, because platform legs already support abundant marine life.
Case study: the SS United States
Later this year the historic ocean liner SS United States is scheduled to be scuttled roughly 20 nautical miles off Destin–Fort Walton Beach, Florida, and is expected to become one of the largest artificial reefs. The 990-foot liner, famed for setting a transatlantic speed record in 1952, will rest at about 180 feet below the surface, where divers and marine organisms will colonize its decks and hull.
Conclusion
Artificial reefs are a valuable restoration and management tool when they are carefully designed, properly sited and paired with broader conservation efforts. They can help rebuild habitat, support fisheries and provide economic benefits—but they do not replace the urgent need to reduce greenhouse gas emissions, curb pollution and protect existing natural reefs.