Despite Progress in Limiting Excess Sewer Flow, Potential Future Development Applications will Still ‘Challenge’ Wilton

Last Wednesday (Oct. 10), Wilton’s Water Pollution Control Authority (WPCA) met to discuss the latest assessment of Wilton’s sewer flows, which officials have been closely monitoring since 2023.

The WPCA has already approved $1.25 million for sewer infrastructure repair work in FY’25, with additional investment likely over the next five years.

In July, following several months of uncertainty about the WPCA’s ability to approve some pending sewer applications, the WPCA approved four new allocations — one for ASML’s expansion plans and three for new multifamily housing developments. The approvals came after much-anticipated results from the Town’s efforts to identify sources of “inflow and infiltration” (I&I) in Wilton’s sewer system. In effect, the expected mitigation efforts freed up some capacity that would allow the estimated additional flows, without the risk of exceeding the contractual limit with Norwalk, which receives Wilton’s sewer flow for treatment.

At the Oct. 10 meeting, DPW Director/Town Engineer Frank Smeriglio gave the WPCA an update, with the latest detailed data on theoretical flows for approved projects, including those currently under construction. As occupancy of those properties increases, the data will shift from theoretical estimates to what is seen in actual flow at the town line.

In addition, Smeriglio reported he had (with input from the Planning and Zoning Department) fine-tuned reserve estimates for numerous vacant buildings throughout town, such as 40 Danbury Rd. (88,000 square feet of office space in the Wilton Corporate Park) and 187 Danbury Rd. (68,000 square feet at the corner of Wolfpit Rd.), among more than a dozen other properties. He explained the importance of factoring in a reserve calculation in the event any of the properties would be reoccupied or redeveloped and begin contributing to flows again.

At present, Smeriglio estimates just over 40,000 gallons per day should be included in the Town’s calculations as a reserve for vacant properties, though he emphasized the estimate was “very approximate” and a “best guess” due to the difficulty of finding definitive data on the vacancies and gauging the accuracy of theoretical flows for those spaces.

The School Sisters of Notre Dame property on Belden Hill Rd. was among the larger properties included in the reserve. The 38-acre campus, which SSND vacated in 2021 and subsequently put up for sale, features a residential building, offices, a chapel, and a school building, among other facilities.

Citing discussions with Town Planner Michael Wrinn, WPCA Chair and First Selectman Toni Boucher revealed that development interest in the SSND property has “become active again” and the “potential for something to happen there is much more probable now, as we see it.”

Boucher called the reserve calculations for vacant buildings “a very wise exercise” because the Town is “obligated to reserve these flows for existing buildings.” The WPCA members in attendance (which included Selectmen Ross Tartell and Kim Healy, as well as Lori Bufano) echoed the praise for Smeriglio’s update.

Boucher said the latest data is “incredibly valuable, to know what our exposure is, should the buildings become occupied again [or] repurposed” and had given the WPCA “a better handle” on Wilton’s position.

“I do feel much more confident about understanding where we stand here in Wilton, and that’s very important given we’re so close to the edge of our capacity,” Boucher said. “It’s critical that we have this at our fingertips.”

Boucher said there were no new applications at the moment but was cautious in setting expectations for Wilton’s available capacity, pending discussions with Norwalk about the possibility of an increase in Wilton’s contractual flow limit.

“We’re really [at capacity] now, there’s no way around it. So anything coming forward — we don’t have anything at the moment — but anything coming forward will involve some serious discussions,” she said.

“My communications with Norwalk indicate they’re moving very slowly and not anxious to engage yet,” Boucher continued, alluding to Norwalk’s own challenges with capacity and repairs.

“The ball is in their court now. We’ve done everything we can, including offering to help them with their I&I issues. We’re waiting on Norwalk to respond,” Boucher said. “It should be noted that any other significant project — we will really be challenged to meet the needs of further applications.”