The world’s oceans are littered with abandoned man-made objects and structures that are considered “repurposed” materials and dubbed artificial reefs. Old tires, toilets, navy ships, oil platforms, retired subway cars, and airplanes, have all either intentionally or unintentionally, been converted into artificial reefs due to the indomitable nature of marine life. Which of these reefs is not like the other? Oil platforms, because unlike the pile of old tires or deserted toilets, platforms span the entirety of the water column, from seafloor to ocean surface, and for years, as the oil companies have been drilling, pumping, and producing, ecosystems have quietly been colonizing, thriving and taking over the legs, crossbeams and joints of these massive structures. This is what makes the Rigs to Reefs program different, no construction required- plus 50-60 years of living proof of its effectiveness functioning as an established artificial reef, making the title “Rigs to Reefs” a bit of a misnomer.
At a first glance, artificial reefs seem to be a relatively new phenomenon, but in fact, they’ve been a part of coastal marine life for hundreds of years. Whether created to protect strategic areas from hostile weather, guard against attacking enemy forces or to improve fish stocks, man has thrown all kinds of objects imaginable into the water. Some of the earliest man-made reefs were created in Japan in the 1600s to improve fish stocks. In India, villagers create triangular concrete structures utilizing the sand from their beaches and then sink them in order to address the damage done by commercial trawling in the area. In the US, the first documented artificial reef in the United States was off South Carolina in the 1830s and was constructed using log huts. More recently, the sinking of naval vessels for artificial reefs, as part of the ‘Ships-to-Reefs’ program, has become relatively common practice and serves several purposes. It creates new ocean habitat and a tourist destination, while also relieving the Navy of outdated ships. From the 1830’s to the present, over 80% of artificial reefs in United States waters have been created using secondary use materials.
The National Fishing Enhancement Act was passed by Congress and signed into law in 1984 and brought special attention to artificial reefs in a broader context of planning and responsibility than had previously been embraced. It is the responsibility of the U.S. Army Corps of Engineers (USACE) to regulate the construction and maintenance of fishing reefs and fishing attractors in waters of the United States including the waters that overlay the outer continental shelf. Building upon this, half of all U.S. coastal states have created artificial reefs or have plans to do so.
You can see that the uses for artificial reefs are many and varied, and the reasons for creating them range from economic, to social enterprise, to environmental repair. But not all artificial reefs are created equal. The location, substrate material, structure size and time of year, all affect the variety and density of species found there. This became apparent after one of our dive expeditions on the shipwreck The Olympic II, who’s hull rests on the seafloor at around 100 feet, followed by a dive on the oil platform Eureka, who’s legs stretch from the ocean surface down to 720 feet, off the coast of California. Only a short, quarter mile, distance from each other the shipwreck and oil platform are exposed to the same offshore currents and opportunistic species but the microcosm ecosystems they each host, are very different.
However, some environmentalists, as well as federal and independent scientists, question whether an artificial reef program provides ecological benefits. Some view the creation of artificial reefs as a dumping ground for unwanted industrial trash and claim it to be an economic shortcut opportunity for recycling. Others note that although most artificial reefs offer potential habitat for certain kinds of marine life, these are not always environmentally harmonious homes. Artificial reefs can cause damage to natural habitats during their construction and can displace naturally occurring species and habitats. Also, because they tend to concentrate fish unnaturally, they can become more vulnerable to overfishing.
Some of the most unexpected and unique reef ecosystems occur on operating offshore oil and gas platforms. Offshore oil and gas platforms first began functioning as artificial reefs in 1947 when Kerr-McGee completed the world’s first commercially successful oil well 11 miles off Louisiana’s shore.. The vast network of energy platforms in the Gulf of Mexico form what is widely regarded as the largest man-made reef in the world, a natural wonder of sorts. Experts estimate that petroleum platforms provide just under 2,000 square miles of reef habitat in the Gulf of Mexico, increasing the amount of reef fish habitat by an estimated 27%. However, due to a variety of liability issues and environmental concerns, federal regulations require that energy companies remove the structures if they are unused for a period of at least 5 years under the Idle Iron Policy. Concerns have mounted in recent years as the pace of removals has increased while little new structure has been placed. Over the history of offshore energy development, nearly 6,000 structures have been placed in the Gulf of Mexico- creating quite a lot of marine offshore real estate- while only one-tenth of these have been reefed.
The Rigs to Reefs initiative first began in the Gulf of Mexico as a way to preserve the habitats that form on the rigs’ steel scaffolding. After a well runs dry or a rig is decommissioned, the tops of the rigs are removed above the waterline and the rest is left for the ocean to reclaim. Today, 260 of the Gulf’s 3,000 decommissioned rigs have been converted into artificial reefs. The Rigs to Reefs program also passed in California- yet to date, due to robust opposition from the public, and particularly trawling fishermen, no platforms have been incorporated into the program.
Oil and gas platforms have proven to be excellent artificial reef material. NOAA’s National Artificial Reef Plan cites five major characteristics or standards for artificial reef materials in order for them to be implemented into the development, siting or planning of a reef. These standards, together with siting and management, generally determine the success or failure of an artificial reef project. These include function, compatibility, durability, stability and
availability, and oil and gas platforms appear to possess all these characteristics.
It is obvious that artificial reefs provide shelter as well as a hard substrate for marine life to colonize and thrive. While I wouldn’t advocate for the sinking of unclean vessels, or other items that may leach heavy metals or other pollutants over time, they are an important piece of evidence demonstrating that nature overcomes, capitalizes and benefits even on these “unintended” artificial reefs. For now, evidence suggests that the practice of reefing oil platforms is a rare policy, and in this ocean explorer’s opinion, an eco-friendly option that pays for itself. However, the question remains, what is the carrying capacity of our oceans? When and how will we know when there are too many man made reefs- and what was once good intention, is now another excuse for throwing unwanted remnants of development into in the ocean? The question for Rigs-to-Reefs supporters has now become whether or not it is good public policy to remove established artificial reefs.