Over the 12 months ending August 30, 2026, Wilton sent Norwalk an average of 484,000 gallons of wastewater a day. The contract between the two towns allows 650,000. By the meter, about a quarter of Wilton's capacity sits unused. By the town's own accounting, Wilton went over the limit in September.
The two numbers can both be true because the figure that counts is the ledger. At the September 23, 2026 meeting of Wilton's Water Pollution Control Authority, the town's planning worksheet added up committed and pending flows at 650,810.8 gallons a day. That puts the town about 810 gallons over its cap, and GOOD Morning Wilton reported that officials described it as the first time the threshold had been reached. If you are comparing Wilton with nearby towns because you want a condo, townhouse or apartment near Wilton Center, this ledger decides how much of that housing can arrive, and in what order.
How 484,000 metered gallons become 650,811 on paper
Wilton has no treatment plant of its own. Its sewered areas, mainly Wilton Center and the Danbury Road corridor, drain to Norwalk's plant, and much of the rest of town uses septic. The town keeps track of the 2010 cap with a working sheet that starts from a conservative base and then adds every project the authority has said yes to, built or not.
The October 14 capacity presentation breaks the September 23 total into four pieces: a net base of 408,730 gallons, built from the first three rows below, plus three categories of projects.
| Ledger line | Gallons per day |
|---|---|
| Net base, part 1: highest measured flow to Norwalk in the last four years | 550,000 |
| Net base, part 2: potential credit for leak-repair work | −172,000 |
| Net base, part 3: volume held for vacant properties and unconnected adjacent homes | +30,730 |
| Projects in construction | +61,896 |
| Approved projects not yet built | +143,467 |
| Pending applications and pre-applications | +36,718 |
| Total | 650,811 |
Projects that are approved but have no shovels in the ground hold more than twice as much capacity as everything now under construction. In Wilton, an approval holds gallons on the books whether or not anything gets built.
The ledger is also kinder than it could be. Under the 150-gallons-per-bedroom standard used for sizing pipes, the same list of projects would total 763,647 gallons a day.
What one apartment costs in gallons
On August 19, 2026, the authority adopted a town-line standard of 65 gallons per person a day. It counts 1.47 people for a one-bedroom, 2.12 for a two-bedroom and 2.94 for a three-bedroom. Run the math and a one-bedroom is charged about 96 gallons a day, a two-bedroom about 138 and a three-bedroom about 191.
That formula is where the argument is. Craig Flaherty of Redniss & Mead, the engineering consultant for Kimco's proposed second phase at 15–21 River Rd., told the authority the town's formula overstates real use. He put the resulting "buffer" at as much as 27,000 gallons. First Selectman Toni Boucher and Interim Town Engineer Steve Santacroce pushed back and called the conservative approach prudent and necessary, according to GOOD Morning Wilton's account of the meeting.
The stakes are concrete. As GOOD Morning Wilton reported, Kimco wants to replace a 118,000-square-foot office building with 225 apartments, which needs 17,532 more gallons a day than the site's current allocation. Including Phase I, the plan would bring the campus to 393 apartments, with about four years estimated to finish the overall project if it is approved, according to GOOD Morning Wilton's July report on Phase II. The authority took no action in September. The Kimco update was on its October 14 agenda.
Old approvals keep their place in line
The worksheet reads like a history of Wilton's development plans. It lists 74 apartments at 300 Danbury Road, approved with conditions in 2019 and still not under construction. It lists 120 apartments at 1 Cannondale Way from 2023 and 206 apartments at 15 Old Danbury Rd. from 2024, both unbuilt. ASML's third wing at 20 Westport Rd., approved in 2025, holds 48,000 gallons a day.
The oldest line goes back further still. Flaherty described a roughly 8,500-gallon allocation for 24 Cannon Rd., tied to a 2009 approval that was never developed, as "highly speculative" and asked that it be removed, GOOD Morning Wilton reported. The October 14 presentation marks that entry as pending further review.
Then there is Belden Hill. The senior-living proposal at 329, 331 and 345 Belden Hill Rd. holds a conditional 2025 allocation of 19,981 gallons a day. Hines SL Wilton Associates and SSND Real Estate Trust withdrew their applications in an October 5 letter, GOOD Morning Wilton reported. The authority has not said publicly whether those gallons go back into the pool. That one decision is worth more than Kimco's whole request, and it would wipe out the September overage several times over.
Who gets the next gallon
Allocations do not go first-come, first-served. Under the authority's stated priorities, capacity goes in this order:
- Businesses deemed critical to Wilton, Connecticut and the United States
- Transit-oriented development
- Wilton Center
- The Danbury Road corridor
Priority does not always win. In October 2025, the authority approved three small housing projects 5-0 even though members worried about the shrinking headroom. Officials said they could not deny the applications without higher-priority requests on the table, GOOD Morning Wilton reported. The courts can also step in. According to GOOD Morning Wilton, after a Connecticut appeals court overturned the authority's 2023 rejection, the authority approved a 15,300-gallon allocation and sewer extension for Baywing LLC's proposed 70-unit building at 19 Cannon Rd. in Cannondale. The approval covers only the sewer. The project still needs other land-use approvals and is expected to be filed under the state's 8-30g affordable housing statute.
Getting more room from Norwalk is not an option for now. According to GOOD Morning Wilton, Boucher said Norwalk had turned down two earlier requests, cordially but firmly, and told the authority:
"If we're at the limit, we're at the limit. That's the bottom line. There's no wiggle room there."
The October 14 presentation says Wilton keeps asking and that Norwalk has not agreed.
The leak repairs are already in the math
Rainwater and groundwater seeping into old pipes take up capacity, and Wilton is paying to seal them. Two bids came in on October 8 for the second phase of sewer rehabilitation. The engineering firm Wright-Pierce recommended National Water Main Cleaning Co. at $571,800 over Insituform Technologies at $806,124. The posted award notice has not been signed yet. The work includes lining about 3,400 feet of pipe, sealing about 400 joints and repairing manholes, much of it along Routes 7 and 106. Wright-Pierce said it does not expect road closures.
The ledger already counts on this. Its 172,000-gallon "potential credit" for leak repair is part of how the town reaches 650,811 in the first place. The repairs help the pipes, but they are not new room on the books.
What this means if you want a smaller home near Wilton Center
The for-sale and smaller-format projects already in the ledger are modest in size: five townhouses at 20 Old Ridgefield Rd., ten condominiums at 254 Danbury Road and twelve multifamily units at 255 Danbury Road. Each was conditionally approved in 2025 and none is under construction yet. Combined, they hold just over 5,100 gallons a day. The 116 apartments at 64 Danbury Road and the 208 at 131 Danbury Road are under construction.
For a buyer, that changes how to read the pipeline. Projects with allocations are the realistic supply for the next few years, and when they arrive depends on construction schedules. A project announced from here on joins a line where priority businesses come first, and it is waiting on decisions about old reserves as much as on demand. These items will tell you which way the ledger is moving:
- Whether the Belden Hill allocation is released after the October 5 withdrawal
- The authority's vote on Kimco's 17,532-gallon request
- Whether the 2009 allocation for 24 Cannon Rd. stays on the books
- Any change in Norwalk's position on the 650,000-gallon cap
A few questions buyers ask
Does this affect a house on septic?
The sewer service area is mainly Wilton Center and the Danbury Road corridor, and much of town uses septic, so the cap mostly concerns properties in or near those areas. If a specific property sits close to a sewer line, the WPCA is the place to ask how it would be treated.
Is Wilton actually close to overflowing its contract?
Not by metered flow. Under the interlocal agreement, as quoted in Kimco's Phase II submission to the town, the towns must meet within six months once a calendar-year average goes above 90 percent of the limit. That would be 585,000 gallons a day. The 484,000-gallon average works out to about 74 percent of the cap.
Why count unbuilt projects at all?
The town's September 23 worksheet carries approved projects on its list whether or not they are under construction, including the 2009 entry for 24 Cannon Rd., which it notes "may be expired." Whether that entry stays on the books is still being argued over.
This post is general information about how Wilton tracks sewer capacity, not legal or engineering advice. If a purchase depends on a property's sewer status, confirm it with the Town of Wilton and the right professional.
If you are weighing a townhouse or condo near Wilton Center and want to know which projects are realistically coming and how they compare with what is on the market today, Sandra Calise Cenatiempo is happy to walk through it with you. Let's connect. You can start with a free home valuation.
