Cannondale well-pumping proposal draws concerns
The Aquarion Water Company of Connecticut has submitted an application to the Connecticut Department of Energy and Environmental Protection (DEEP) for a permit to pump up to one million gallons of water per day from the Cannondale well field at 3 Cannon Road.
Aquarion is a public water company, and subsidiary of Eversource, that supplies water for more than 625,000 people in 51 Connecticut municipalities.
Peter Fazekas, Aquarion’s public relations director, said the permit process is expected to take approximately six months to a year, and Aquarion is scheduling meetings with stakeholder groups, including a private working session with some on Nov. 7.
“Stakeholders that will be attending include Harbor Watch, Norwalk Harbor, Rivers Alliance, Norwalk River Watershed Association, Trout Unlimited, Town of Wilton, South Norwalk Electric and Water, and Norwalk First District Water Department,” said Fazekas, adding that a meeting location has not yet been determined.
After purchasing 3 Cannon Road in 1981, Aquarion installed the production well on the property in 1982 in order to “provide an additional water supply for our system,” Fazekas told The Bulletin. Since then, Fazekas said, the well has been inactive and used only for “testing purposes.”
After experiencing “the worst drought since the 1960s in 2016,” Aquarion has been reviewing “all additional water resources available in [the] region,” said Fazekas.
“The well is located near our water transmission mains, so it makes sense to bring it online to ensure sustainability and resiliency of our water resources,” he said, noting that Aquarion had to “run temporary, emergency water mains along the Merritt Parkway to move more water to this region.”
According to Aquarion’s diversion of water for consumptive use permit, prepared in October 2018 by Shelton-based engineering professional services firm WSP USA, up to one million gallons of water would be pumped from the Cannondale well each day in order to “augment the Greater Bridgeport System — that includes Wilton — which is being relied upon to meet supply deficits in the southwest Fairfield County service area, as well as the Ridgefield service area.”
Not only would utilizing the well “provide resiliency and reduce the strain on the infrastructure currently serving these interconnections in Fairfield, Westport and Wilton,” according to the application, but “Cannondale Well production will reduce withdrawals from the Hemlocks Reservoir System, improving drought resiliency and [Aquarion]’s ability to maintain future reservoir releases in compliance with the Connecticut Department of Energy and Environmental Protection Streamflow Standards and Regulations.”
Water withdrawn from the Cannondale well would be treated and pumped into Aquarion’s distribution system and become part of its potable water system, Fazekas explained to The Bulletin.
There are more than 50 properties within 1,000 feet of the well field, and Fazekas said Aquarion “does not expect any impact on neighbors from mechanical noise on the site.” Noise, however, isn’t as much of a concern for some in the community as are the environmental impacts on groundwater, the Norwalk River, nearby wetlands, and species in the area.
State Rep. Gail Lavielle (R-143) mentioned Aquarion’s project during the Oct. 16 Wilton League of Women Voters-sponsored candidate debate at Middlebrook School, stating that while she is “concerned,” she doesn’t know “how concerned [she is] yet because [she doesn’t] have all the information.”
Louise Washer, president of the Norwalk River Watershed Association (NRWA), said she has “serious concerns” that include “the negative effects this proposed diversion might have on nearby wetlands, on the health of the river and its aquatic life, and on groundwater levels and possibly private wells nearby.”
The Cannondale well field is situated within the Norwalk River watershed, according to an environmental evaluation report prepared by Westport-based engineering and planning company LandTech Consultants, and its projected zone of influence encompases portions of the Norwalk River and Goetzen Brook, as well as their associated floodplain wetlands.
According to LandTech’s report, aquifer tests conducted by Shelton-based ground-water consulting firm Leggette, Brashears & Graham, Inc. in 1984 and 2013 revealed that at a diversion rate of one million gallons per day, the estimated potential reduction of flow in the Norwalk River would be approximately 0.46 cubic feet per second or 208 gallons per minute. During low flow periods, according to the environmental report, well-pumping would reduce the Norwalk River’s flow by 10%.
In response to the aquifer test results, an ecological baseline survey was conducted between May and October 2017 to further characterize vernal pools in the area. From that survey, according to the environmental report, a mitigation plan was developed for the first five years after issuance of a permit in order to “minimize impact to flow in the Norwalk River” and “monitor surface water and groundwater levels” in the floodplain and mitigation wetlands.
At the DEEP’s request, piezometers were also installed and monitored for 72 hours to measure the groundwater pressure of the Goetzen Brook, which flows west of Route 7 and into the Norwalk River north of the Riverbrook Regional YMCA’s driveway culvert. According to LandTech’s report, the results showed that pumping the Cannondale well would create “no discernible impact” on the brook.
To protect amphibian breeding habitat in the area, the environmental report states, “water levels must be maintained during the late winter through spring breeding season,” “seasonally saturated soil conditions also need to be maintained to preserve existing and created wetland habitats within the floodplain wetlands,” and “well withdrawals need to be incorporated into an overall water management plan to mitigate impacts to wetland water levels.”
The project site is also within an area identified as a habitat for endangered, threatened or special concern species. However, a 2011 review by the DEEP indicated that while the presence of white river crayfish and ground beetles have been recorded in the vicinity, according to the environmental report, “the proposed well connection to the public water supply [would] not negatively impact these species.”
The environmental report also mentions ways to “protect” trout habitat in the well field’s vicinity, such as by incorporating the maintenance of “stream base flow” and “well withdrawals” into “an overall water management plan to mitigate impacts during low flows.” The report also states that maintaining some deep water pools for adult trout and riffle habitats for juvenile trout during low flow periods would also be necessary, and “the enhancement of trout habitat through the creation of additional habitat cover for all life stages of brown trout should also be considered.”
Although he doesn’t yet know the full details of Aquarion’s proposal, Trout Unlimited Volunteer Operations Director Jeff Yates said he does have some early concerns about the impact well-pumping would have on the flow of the Norwalk River.
“Generally speaking,” Yates said, “any type of activity that involves pumping groundwater near a watercourse will have some type of impact on the surface flows of that stream.”
Yates said Trout Unlimited wants to see Aquarion’s proposal and “make sure the impacts it has on the Norwalk River are mitigated to prevent changing the flows to the stream” — especially in critical periods for trout and other aquatic species.
The Norwalk River is home to wild brown trout and will soon have sea-run fish like American eel and shad “coming into Wilton” thanks to a dam removal project in Norwalk,” said Yates. “Any reduction in flow could impact their success.”
Although he doesn’t know what to expect when it comes to a Nov. 7 meeting, Yates said his hope is that Aquarion “want[s] to get our feedback before they move forward with their final formal proposal.”
“Any reduction in flow in Norwalk River is going to have impact on the aquatic ecosystem,” said Yates.
Water withdrawal, however, is “only one side of the coin,” said Yates — “storm runoff needs to also be addressed.”
Storm runoff is created “when rain falls on roads, driveways, parking lots, rooftops and other paved surfaces that do not allow water to soak into the ground,” according to the Center for Watershed Protection, and when these large volumes of water are carried to streams, lakes, wetlands and rivers, they “can cause flooding and erosion, and wash away important habitat for critters that live in the stream.”
With all the development in the area, Yates said, “one of the biggest challenges facing the Norwalk River” is less recharge of groundwater.
“Basically speaking, we’ve paved the heck out of the watershed and that pavement prevents rain from soaking into the ground,” he said, “so over time, as we’ve developed more of the watershed with housing and commercial buildings, we’ve reduced the watershed’s ability to absorb water and recharge aquifers.”
Aquifers “feed the water in the winter,” said Yates, and one of the things Trout Unlimited is working towards is “reducing storm runoff and increasing groundwater absorption in the watershed through projects that will recapture rain water.”
Yates added that “too much pumping at the wrong time of year” could also “run the river dry.”
The application is also available for inspection at the Connecticut DEEP’s Inland Water Resources Division office at 79 Elm Street in Hartford, Monday through Friday from 8:30 a.m. to 4:30 p.m.