BY ROD HANSEN
Though many residents blame dam control for the April 16 flooding, state officials recently said the heavy water flow went beyond a local dam’s discharge capacity.
At a special community meeting on Saturday, April 21, regarding the floods, about 40 residents turned out at the Goffstown High School Heiber Auditorium for answers from local and state officials about the emergency.
One of the most anticipated speakers was James Gallagher, chief engineer of the state’s dam bureau.
“I’m very, very troubled to be back here after last year,” Gallagher said.
Facing the crowd’s claim that dam management led to local flooding for two consecutive years, Gallagher said the problem lies in the amount of water the downstream dam can release.
The Kelley Falls Dam, which sits downstream from the Greggs Falls Dam on the Piscataquog River, has a discharge capacity of 600 cubic feet per second of water, Gallagher said.
The Piscataquog reached a peak flow of 11,100 cubic feet per second during the height of the storm at midnight on Monday, April 16, according to a chart available at the meeting.
The Kelley Falls Dam is owned by the state and leased to Enel North America of North Andover, Mass., through its subsidiary Consolidated Hydro of New Hampshire Inc.
The hydroelectric generator’s presence at the dam reduces Kelley Falls’ discharge capacity by approximately 500 cubic feet per second, Gallagher said.
A University of New Hampshire engineering study shows modifications to the dam could increase discharge capacity and reduce water levels by as much as 3 feet upstream, Gallagher said. However, he said these modifications could cost as much as $2 million to complete.
The cost of buying out the remainder of the lease on the dam could also cost $2 million, Gallagher said.
Martha Fournier, a resident of Lynchville Park, said the flooding conditions could justify that expense.
“This could be a reason to get out of the contract,” she said.
Roger Paradis, a longtime resident of Lynchville Park, said his house had suffered serious damage in last year’s flooding as well as the recent nor’easter.
“There’s nothing I’m hearing here where you’re taking responsibility,” Paradis said, noting that he had not seen flooding in 33 years before being flooded twice in the past 11 months.
Gallagher said the floods of 1936 and 1938 happened within 21 months of each other.
“We think we had just had a 100-year flood, so we can wait another 100 years. But the truth is, we could have another event in two weeks,” Gallagher said.
The chart detailing the Piscataquog’s flow during the heavy rains outlined actions taken by dam operators in anticipation of the storm. According to that chart, Kelley Falls opened its waste gate on the morning of Friday, April 13, with Greggs Falls fully opening one waste gate and partially opening another at 2 p.m. the following Sunday.
The Everett Dam, which lies furthest upstream, had been shut down to 50 cubic feet per second by 4 p.m. on Sunday, and Greggs Falls had fully opened both waste gates by 7:30 a.m. the following day.
Greggs Falls had activated its emergency action plan by 3 p.m. that day, when flow had reached 10,000 cubic feet per second.
Fournier said warnings of a coming storm should have prompted earlier action.
“I was e-mailing my neighbors about the storm on Thursday night, and I’m just an ordinary citizen,” Fournier said.