Sea stars take to the man-made reef off Gooseberry Island that was formed with concrete debris from the demolished Jamestown Bridge. Other creatures, including scup and sea bass, are starting to call the reef home.

Photo courtesy of Oceans of Opportunity

When the last remnants of the Jamestown Bridge came tumbling down nearly two years ago, state officials had already devised a plan for the mountains of concrete debris: turn them into an intricate reef system to support marine life.

Over a period of months, most of the 26,000 cubic yards of debris was barged to two locations off Newport — one about 1½ miles south of Gooseberry Island, the other about a half-mile east of the city’s Sheep Point — to form artificial reefs each 650 long and about 200 feet wide, the first of their kind in Rhode Island waters.

Rising as much as 15 feet above the flat, barren sea floor, the concrete reefs were anticipated to attract and provide habitat for crustaceans and fish.

Judging what research divers observed in recent visits, the systems seem to be doing their job.

“If you really want to see how a reef is performing, looking at fish is a good way to do that,” said Natasha Pinckard, a marine biologist for the Navy in Newport and a part-time student at the University of Rhode Island’s Graduate School of Oceanography. “So far, it looks like a success.”

Pinckard, who is completing her master’s thesis on the reefs, said the divers saw schools of scup and sea bass as well as starfish and other simpler marine organisms on or near the reefs during a dive early this month.

The reef project, led by the state Department of Transportation, is among the more unusual endeavors for an agency whose traditional bailiwick is highways and bridges. “We usually don’t build reefs, we usually build roads,” said Charles St. Martin III, a DOT spokesman. “There was the option to landfill it [the debris] or try this.”

Artificial reefs have been around for thousands of years, for diverse purposes ranging from military defense (the Persian Empire) to the creation of more surf-friendly breakwaters (California). Many modern artificial reef systems are being placed to supplement existing reefs as habitat for wildlife.

The nonprofit Reef Ball Foundation alone has placed more than 4,000 reefs in 59 countries, including the United States.

However, recent efforts have not been without missteps.

In the 1970s, an ill-conceived, tire-based Osborne Reef off Fort Lauderdale, Fla., turned into an environmental disaster when the nearly 2 million tires broke loose from the flimsy metal clips holding them together.

Ocean currents, tropical storms and hurricanes joined in sending the tires crashing into natural reefs and washing them up on the shores of Florida and the Carolinas. Several decades and millions of dollars later, all of the tires have yet to be removed.

Despite an imperfect history, artificial reefs have enjoyed a good deal of success. But their proliferation has not occurred without controversy, Pinckard said.

The prominent debate centers on whether man-made reefs are being used exploitatively — to draw fish in only to harvest them — rather than with the aim of creating a healthy, permanent home for fish and other organisms on all levels of the marine food chain.

Ocean Conservancy, an environmental advocacy group, is skeptical about the benefits of artificial reefs.

“Although most artificial reefs offer potential habitat for certain kinds of marine life, these are not always happy homes. Artificial reefs can cause damage to natural habitats during their construction and can displace naturally occurring species and habitats,” the group says on its Web site. “They also tend to concentrate fish unnaturally, making them more vulnerable to overfishing. In some cases, they introduce toxins and other pollutants into the ocean.”

St. Martin, at the DOT, said the primary motivation for the placement of the reefs off Newport was to satisfy the environmental mitigation requirement attached to the Jamestown Bridge demolition, and that recreational, but not commercial, fishing is a positive secondary result.

“It wasn’t built just for good fishing,” St. Martin said.

The DOT receives scientific and research support from the state Department of Environmental Management, which is monitoring and studying the population of commercially viable fish such as scup, flounder, bass and bluefish, some of which were observed on the recent dive in May.

“A lot of natural habitat are being negatively affected by humans, whether [through] pollution, overfishing, warmer waters, coral bleaching … and they [fish] don’t have anywhere to go,” said Michael Lombardi, president of Oceans of Opportunity, a nonprofit ocean exploration organization which helped coordinate and support the recent observation dive. “We found what appears to be the beginning of a very healthy reef.”

ngarcia@projo.com