As dams go, the Whittendon Pond Dam is unremarkable. But the threat of its collapse this week forced the evacuation of 2,000 residents, closed schools and businesses, and kept flood-wary residents asking if the 173-year-old wooden structure would hold.
The days of drama here in the old mill town of Taunton, Mass., also renewed an old debate: Are these aging dams still a vital part of the nation's infrastructure? Or are they just hazardous relics of an industrial past?
Of the more than 79,000 dams listed by the National Inventory of Dams, only a fraction have been decommissioned.
But that is changing quickly.
In many cases, it is cheaper to remove an idle dam than repair and maintain it. As dam owners learn more about liability, many are opting to shut them down rather than bear the consequences of a safety hazard. And a push to restore free-flowing rivers and fish habitats is also playing a role.
"It is becoming more popular to close down dams," says Bill Hover, chair of the Dam Decommissioning Committee at the US Society on Dams.
He says that dams are part of America's forgotten infrastructure, but an event like the one in Taunton makes a policy debate top of mind. "People learn more about what can happen when a dam doesn't operate the way you want it to."
The crisis in Taunton, a city of more than 50,000 residents, came to a head after seven inches of rain fell last weekend, swelling the Mill River to near-flood levels.
On Tuesday, some parts of the privately owned dam swept away. Since then, emergency crews - and national media - have converged on the scene.
The situation ushered rapid change in the state. Gov. Mitt Romney ordered the immediate inspection of 186 dams, both privately and publicly owned, that could also pose risk to lives or property if breached. There are some 3,000 dams throughout the state.
States monitor about 95 percent of the nation's private and public dams, says Lori Spragens, executive director of the Association of State Dam Safety Officials in Lexington, Ky.. Many dam safety departments, she says, are understaffed.
At least 10 states, including Massachusetts, are shifting inspection responsibilities to dam owners.
Ms. Spragens, whose group advocates stronger dam-safety programs, says that such a shift, if done right, will not lower standards of safety. "It doesn't take the responsibility off the state [to enforce safety]," she insists.
Because many dams were built centuries ago, the cost of repair and compliance can be far more expensive than removal - three times more, according to some estimates.
That is a major reason 175 dams have been removed since 1999, says Elizabeth Maclin, director of the dam removal campaign at American Rivers, an environmental group in Washington. "Dam removal has been going on for centuries," she says, adding that the number of those being removed is increasing.
This year, some 56 dams - many of them small and old - are slated for demise.
In Wisconsin, considered a leader in dam removal, most closures came about because of safety concerns.
For many owners, the costs of ownership are simpy too high, says Meg Galloway, the state dam safety engineer at the Wisconsin Department of Natural Resources. But fear of blame is playing a larger role, too. "Owners are becoming more savvy," she says, "and less comfortable taking on the liability of dams."
Residents near Mill River, meanwhile, are anxious for news of the Whittenton Pond Dam's condition.
Officials say a worst-case scenario would send a six-foot wall of water coursing downstream through downtown Taunton, a working-class city about 40 miles south of Boston.
"The hardest part is not knowing," says Kevin Strong, who has taken shelter with his two sons at Taunton High School since Monday night. "If it does go, everything I worked for is gone."
The city's largest flood came in 1886, some 50 years after the dam was built, says Charlie Crowley, a city council member who also writes books and gives tours of Taunton.
Repairs then allowed the dam to flourish, as immigrants poured into the city for textile and silversmithing jobs that abounded. It has been more than 30 years since the city last flooded.
A lull amid an unusually rainy October has helped water levels recede, but expected rainfall this weekend has officials on continued alert.
As in Massachusetts, New Jersey has also increased scrutiny following a series of dam failures there last year, says John Moyle of New Jersey's Bureau of Dam Safety and Flood Control. New procedures allow his office to fine safety code violators.
But of the 1,700 dams the state monitors, few owners have opted for removal, says Mr. Moyle. Why? Real estate. Owners who built their homes around the bodies of water that dams create hold fiercely onto their waterfront views.
"It may be costly to repair a dam," says Moyle, "but no one wants to [go from] looking at a lake to looking at a wetland area."
Environmental awareness may not be the principal reason that dam owners are opting to remove their structures. But when dams serve little direct function - such as walling in a community's drinking water or working as flood-control devices - Hover says he is seeing more owners interested in restoring rivers to free-flowing conditions.
That has happened on the Snake River and many dams in the West. And that is a big change. Says Hover: "Ten to 15 years ago, engineers and dam owners just weren't thinking about [removing] dams to improve the environment."