SMITHFIELD, R.I. — In need of repair for more than a decade, the Slack Reservoir Dam has been declared unsafe and likely to fail in the event of a heavy storm.

In a worse-case scenario, 400 million gallons of water could fill the bowl below in just 30 minutes, said Mark Barnes, president of the association that owns and maintains the dam.

A nearby parking lot could be covered with 8 feet of water, and a wall of water would hit 46 other businesses and homes almost immediately.

"I'm going to be a total loss if that happens," said Paul Osenkowski, a dentist with an office across from the dam.

Thousands of New England residents live and work downstream from centuries-old dams in need of repair, and fixing them could take years and millions of dollars, according to interviews and a review of government documents conducted by The Associated Press.

An AP review of documents in Rhode Island, Massachusetts and Connecticut, as well as interviews with state officials and dam owners, found many dams are not inspected as often as they should be and some go years without recommended repairs.

In many cases, private owners are reluctant to shoulder repair costs or cannot afford to do so. In others, the government has been unable to act or unwilling to spend the money.

If the dams fail -- as nearly happened this fall when heavy rains threatened the 173-year-old Whittenton Pond Dam in Taunton, Mass., and forced the evacuation of 2,000 residents -- homes, businesses and lives are at risk.

There are more than 7,000 registered dams in southern New England, according to state records. Many date to the late 1600s, said John Harris, director of Monadnock Institute of Nature, Place and Culture in New Hampshire.

Dams that would likely kill someone or cause a lot of property damage if they failed, such as the one at Slack Reservoir, are designated as "high hazard."

Until recently, Rhode Island listed just 17 high-hazard dams. But development has put homes downstream from dams that were once secluded. When the state recently reexamined its dams, it found 61 -- more than three times as many -- should be listed as high-hazard, said David Chopy, who oversees dam inspections in Rhode Island.

Massachusetts has 320 high-hazard dams, while Connecticut has 237.

While the high-hazard label does not mean a dam is in poor condition, many are. The three states have declared 22 high-hazard dams unsafe, meaning they are in imminent danger of failing in a heavy storm. Fifteen of those dams are in Connecticut, five are in Rhode Island and two are in Massachusetts -- where dam inspectors recently suggested another unsafe dam be added to the list.

Federal guidelines call for high-hazard dams to be inspected every two years, but in many cases, they haven't been. Following the near-disaster in Taunton, Massachusetts Gov. Mitt Romney ordered inspections of 186 high hazard dams in unsafe, poor or fair condition. Before this fall, at least 30 of those dams hadn't been inspected in seven years and five went longer between inspections.

None of the three states has enough inspectors to meet standards outlined by the Association of State Dam Safety Officials. The inspectors do their best, but they have a near impossible task, said Sarah Mayfield, the group's spokeswoman.

"Policy-makers aren't adequately funding dam safety offices," she said. "It's an easy issue to ignore until, of course, something goes wrong."

Money -- for inspectors and repairs -- is a universal problem. In Rhode Island, a third of the state's high hazard dams have features that are in poor condition. It would cost an average of $800,000 per dam to bring them up to code, a recent DEM report said.

Seventy percent of Rhode Island's dams are privately owned, which makes them largely ineligible for publicly funded repairs. In Massachusetts and Connecticut, at least 90 percent of dams are private.

Publicly owned dams are not necessarily in better shape. The Massachusetts Office of Dam Safety estimates it needs $32 million to bring the dams owned by the state up to current safety standards. Town and city officials say they also need money to fix dams.

It's hard to convince people to spend money on something they don't see, said Roger Hammond, director of public works in Grafton, Mass.

"When you're asking for money for a dam versus two or three new teachers, we're probably not going to win that one," he said.

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Associated Press Writers Brooke Donald in Boston and Susan Haigh in Hartford contributed to this report.

Source: Associated Press