Critics doubt study about causes of Connecticut River erosion

NORTHFIELD — A long-awaited study of the Northfield Mountain Pumped Storage project reports that the hydroelectric facility is responsible for only 4 percent of the erosion along the banks in the 20 miles between Turners Falls and Vernon, Vermont.

The first-of its kind “causation study,” paid for by FirstLight Hydro Generating Co., is still being completed by engineers for the company, which has been criticized for years by environmental groups including the Connecticut River Watershed Council and by the Franklin Regional Council of Governments as a major cause of bank erosion in the 20-mile “Turners Falls Pool” between dams in Turners Falls and Vernon that serves as the generating plant’s lower reservoir.

The study is part of the hydro-generator’s pending federal relicensing.

The 60-page executive summary released Sept. 1, written by Simons and Associates, Gomes and Sullivan and Cardno, points to “naturally occurring moderate and high flows” of the river as 78 percent of the cause for bank erosion in that stretch.

Boats account for 13 percent of all erosion on the riverbank in this segment, compared to 16 percent with all stretches of the river studied.

Also, the study finds, “Based on analysis of historic information from the Connecticut River, as well as other river systems, ice has the potential to be a naturally occurring dominant cause of erosion in the (Turners Falls Impoundment) in the future given the right climatic and hydrologic conditions. Due to the hydrologic and hydraulic characteristics of the TFI, it is anticipated that hydropower operations will have limited to no impact on ice as related to bank erosion.”

Tom Miner, on the Franklin Regional Planning Board and the Connecticut River Streambank Erosion Committee, told the Planning Board recently that the two-year study’s results were “astonishing,” yet at the same time said the findings are “no great surprise,” given the source. The erosion committee has been advocating over the past 25 years for Northfield Mountain’s owners to assume more responsibility for controlling erosion that many of its members contend is largely caused by routine operations of the pumped storage project.

“We now know precisely what we have to deal with in the relicensing process. Those of us who have been working on the stream bank erosion committee since the early ’90s and on this relicensing for the last six to seven years know that there’s a much more complex set of issues here.”

The underground pumped-storage power plant uses Connecticut River water pumped up the mountain overnight, when electricity prices are lowest, and releases it when there is peak demand and prices are highest, providing the region’s electricity grid with 1,168 megawatts of power.

A new license for the project is scheduled to be issued in April 2018, Miner said. “So we have our work cut out for us. Now is the crunch time” in responding to the company’s studies.

Miner told the Planning Board, “To basically have a pumped storage project that treats the Connecticut River like a tidal river, up and down every day” yet claim that its report that there is virtually no impact on erosion “is nonsense. … The First Light characterization of this lack of responsibility speaks for itself.”

Miner said the challenge for the Council of Governments, the erosion committee and the Planning Board will be to have their own scientific study done to examine the results of the company’s report. In the next week or so, he added, the Council of Governments’ staff plans to meet to discuss performing an evaluation of the study.

The private, nonprofit watershed council plans to analyze the complete causation report for Northfield Mountain, which is expected to be released with a detailed appendix Oct. 16, according to its river steward, Andrea Donlon.

“Definitely, this is the most detailed study about the current erosion conditions and their causes, using a scientific model to look at the causes,” said Donlon, adding that it could have “huge implications” for how Northfield Mountain is allowed to operate and to what extent its owners would be required to stabilize the banks and prevent further erosion.

Originally built by Northeast Utilities, the 44-year-old underground power plant has changed ownership several times, with current owner Engie North America now selling it to the Canadian pension fund PSP Investments.

If the plant’s operation was shown to be a much more significant contributor to erosion, Donlon said, FirstLight could be required to operate the plant differently than the maximum 9-foot fluctuation now allowed.

In fact, she said, the company’s license application has called for an amendment allowing greater use of its mountaintop Upper Reservoir. And on Sept. 16, FirstLight filed an application with the Federal Energy Regulatory Commission  for a temporary amendment in its operating license from Dec. 1 through March 31 to once again boost water-storage capacity of its mountaintop reservoir.

The change, which has been approved on a temporary basis five times, would allow an additional 22 feet of pumping capacity at Northfield Mountain’s 5-billion-gallon reservoir by changing upper and lower water surface elevation limits “to increase its operational flexibility and provide (the regional power pool) with additional energy reserves to deal with potential reliability challenges in New England this winter.”

Meanwhile, the watershed council has been doing what its executive director Andrew Fisk calls “a very general analysis” into having an alternative lower reservoir that would eliminate the need to use the river for water used in power production.

Although a request to the federal commission to study a “closed-loop” operation as part of the relicensing was rejected after being opposed by the company, Fisk said the concept should be analyzed as a way of allowing the company to use the full capacity of the mountaintop reservoir without causing environmental harm to the river.

“That ongoing process, it will be a very hard row to hoe if we have a project that FERC decides has no impact, currently, on the Connecticut River,” Miner said. “So all these pieces fit together.”

The new study is part of relicensing not only the Northfield Mountain and Turners Falls hydroelectric projects but also TransCanada’s Vernon, Vermont, Wilder and Bellows Falls projects. It involves what it says are “state-of-the-science modeling and supplemental engineering analyses at 25 detailed study sites located throughout the study area” over 15 years.

Greg Snedeker, who has lived on the river in Gill for 24 years, told Miner and others, “I read the report, and I could only laugh, because if I didn’t laugh, I was going to cry. It’s just horrendous. Those of us who live on the river, we see the erosion. We see it every winter, when they lower it down …. (with) the mud literally falling into the river.”

Snedeker said that the impact of boats along the river has been worsened since FirstLight began lowering the water level several years ago to maximize how much water it could pump and then release from the mountain reservoir.

“When the boats go by, the erosion is worse because the river’s been lowered to the point where there are drop-offs from the erosion, so when the  waves hit, it just takes and hits the drop off and pulls the mud down. This is wreaking havoc. Those of us who live on the river, we see it on a daily basis.”

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