The cinema at 119 W. Montauk Highway has already had its seats taken out. The 2.7-acre shopping center that held the Regal UA for decades changed hands on June 22. Its longtime owner told Patch that the sale went through lawyers and that he could not disclose who the buyer was. According to 27east, he did not know the buyer's plans, and the Melrose Deli, one of the center's five other businesses, still has seven years on its lease.
In downtown Hampton Bays the first thing that decides what goes in that space is the amount of wastewater the site is allowed to put into the ground. The business district has no sewer. Each building runs on its own septic system or cesspool, and the Suffolk County Department of Health Services caps how much each lot can handle. That cap explains why Main Street has changed so slowly over 15 years of planning. It also means the downtown a buyer sees this fall is mostly the one they will see for several years.
The County Measures a Building in Gallons Per Day
Under Article 6 of the Suffolk County Sanitary Code, a change of use counts as a "New Other Construction Project" when it needs new sewage disposal facilities or more capacity in the existing ones. Once a project is in that category, the code compares its wastewater load with what the land would produce as a subdivision of single-family lots of at least 20,000 square feet, or at least 40,000 square feet in Groundwater Management Zones III, V and VI. When a project goes over that benchmark, the code requires a community sewerage system.
The Department's construction standards, dated July 21, 2020, turn that benchmark into numbers. A commercial lot gets 600 gallons per day per acre. In Zones III, V and VI, or where public water is not supplied, it gets 300 gallons per day per acre. Each use is then charged against that allowance at its own rate:
| Use, per the County's Table 1 | Density load | Hydraulic load |
|---|---|---|
| Restaurant, full service or over 16 seats | 10 gpd per seat | 30 gpd per seat |
| Outside patio dining | 5 gpd per seat | 15 gpd per seat |
| Bar inside a restaurant | 10 gpd per seat | 15 gpd per seat |
| Wet store or deli/take-out, 16 seats max | 0.03 gpd per sq ft | 0.15 gpd per sq ft |
| Convenience store, market or farm stand | 0.03 gpd per sq ft | 0.05 gpd per sq ft |
Restaurant uses are charged by the seat, and retail uses are charged by the square foot. That difference matters a great deal on a lot that is already close to its limit.
One Half-Acre Lot, Two Possible Tenants
Here is the standards' arithmetic applied to a hypothetical half-acre lot on Montauk Highway, before any other use on the site is counted:
- Half an acre at 600 gpd per acre gives an allowance of 300 gallons per day. At the stricter 300 gpd per acre, it gives 150.
- A 2,000-square-foot deli or take-out shop is charged 0.03 gpd per square foot, or 60 gallons per day. That fits under either allowance.
- A 40-seat sit-down restaurant is charged 10 gpd per seat, or 400 gallons per day. That is over both allowances.
- At 10 gpd per seat, the 300-gallon allowance stops at 30 seats. The 150-gallon allowance stops at 15, which is below the 16-seat line where the restaurant rate begins.
Town Planning and Development Administrator Janice Scherer made the same point at a May 7 panel reported by 27east's Express Sessions. She said most buildings' old cesspools and septic systems "do not allow for almost any change at all," and she put the consequence for owners plainly: "Your business model has to be able to change, and if you can't get through the [Suffolk County] Health Department, you're done."
This is why a building's assessed value and asking rent do not tell a buyer what it could become. A storefront full of retail shelving is legally a different property from the same square footage set with dining tables, and the County's table is what separates the two.
Even Waterfront Restaurants Are Short on Room Underground
The limits are just as tight for businesses that are already open. In September, 27east reported that Rooted Hospitality, which owns Rumba and Cowfish near the southern mouth of the Shinnecock Canal, had asked the town for roughly $800,000 in water quality grants: $437,000 for Cowfish and $310,000 for Rumba. The money would go toward nitrogen-reducing septic systems.
Rumba sits on a small lot between residences. Its current system was replaced in 2014 and lies under the driveway. A new system would mostly have to go beneath parts of the building itself. Brian Grogan, the engineer working for both restaurants, told the Town Board that much of the parking lot is "unusable from a septic standpoint because groundwater is only a foot or so down." The new systems are expected to discharge less than 10 milligrams of nitrogen per liter, down from as much as 65 in the current ones.
Neither restaurant is on Main Street. Their case still shows the problem downtown faces. On a small Hampton Bays parcel, the room available underground can limit a business more than the floor area above it.
The Town's Fix Is Planned Next to the Jackson Avenue Campus
In March, the Town Board voted unanimously to buy 31 acres on Old Riverhead Road from Hogan Southampton LLC. The town would pay $3.2 million from Community Preservation Fund water quality money, plus $465,000 from general funds for 4.8 acres that would join the town's Jackson Avenue complex. About 6 acres of the parcel are set aside for a treatment plant that would serve the downtown business district and some neighboring parcels.
The estimates of plant size show the gap between the downtown as it is and the downtown the town has in mind. At the May panel, the town's consultants said existing businesses and the few connected residences would need about 280,000 gallons per day, and early talks put the plant's capacity upward of 400,000 gallons. As 27east reported when the land deal was announced, a 2023 town study had recommended about 550,000 gallons per day, roughly twice the current downtown flow, so the plant could take on new development. That study also said: "Downtown business districts that don't have sewers are struggling. Downtown business districts that do have sewers are flourishing."
The timeline is long. In that same 27east report, Supervisor Maria Moore estimated about two years of design after the purchase and another two years to build. According to 27east's coverage of the lawsuit, the site's only neighbor has sued to annul the purchase on SEQRA grounds and because the land sits in a Central Pine Barrens critical resource area. Justice Alison Napolitano declined to issue an injunction stopping the town from going ahead. The neighbor's attorney raised the Pine Barrens Act objection again at the town's August 25 hearing. That hearing covered $300,000 in Community Preservation Fund money for reports, geotechnical work, public engagement and on-call engineering to set up a sewer district. A resolution to authorize that funding was on the board's September 8 agenda.
A Sewer Removes One Limit, and Zoning Is the Next
A treatment plant would lift the County's gallons-per-acre cap. It would not change what the town's zoning code allows. As 27east has reported, Hampton Bays already had a Downtown Overlay District, which a resident's lawsuit overturned, and the courts voided those code changes. The same outlet has covered the best-known private plan, from developer and longtime Hampton Bays resident Alfred Caiola. It calls for a new Main Street running perpendicular to Montauk Highway and ending at Good Ground Park. The new street would have ground-floor retail with up to three stories of apartments above, on land he owns between Main Street and the park. A plan like that would need both the sewer and new zoning.
Councilwoman Cyndi McNamara pointed to this at the May panel: "The question is about sizing it, and then you get into density questions." The size of the plant sets an upper limit on how much the downtown can grow, and the zoning code decides how much of that capacity actually gets built.
What to Watch Before the Pipes Arrive
| Milestone | Where it stood this fall |
|---|---|
| Design-engineering funding, $300,000 | Hearing held August 25; resolution on the September 8 agenda |
| Old Riverhead Road land | Purchase approved in March; neighbor's lawsuit filed, injunction denied |
| Sewer district study | "Hampton Bays Sewer District Implementation Study," $47,832, in the tentative 2027–2031 capital budget |
| Replacement downtown zoning | Earlier overlay voided by the courts |
| 119 W. Montauk Highway | Sold June 22; buyer's plans not made public |
A buyer looking at a home near the business district is buying into the downtown that exists now. Using Moore's estimate of about four years from purchase to a working plant, followed by a separate zoning process, the restaurants and apartments in the Caiola plan are probably years away. For a commercial buyer, the main question about a building is its septic allowance and how much of it is already used.
Frequently Asked Questions
Can an existing downtown Hampton Bays store become a café?
That decision belongs to the Suffolk County Department of Health Services, applied to the specific site. The published rules treat a change of use that needs more septic capacity as a new project, and the County's table charges full-service restaurant seats at 10 gpd each in density load, far more than it charges retail floor space. An owner should have an engineer or attorney review any particular building.
Would a sewer raise nearby home values?
None of the town's documents make that projection. What the town has said is that a sewer is meant to allow new downtown development, including apartments above shops. How much of that happens depends on zoning that has not yet been adopted.
Does Hampton Bays pay for this through property taxes?
So far the land and the design request have used Community Preservation Fund water quality money, which comes from a 2 percent tax on most real estate purchases. The town has not yet made public how a future sewer district would be financed.
This post is general information, not legal, tax or financial advice. If you own or are considering a property affected by these rules, confirm its specifics with an attorney, engineer or other qualified professional.
If you own a downtown Hampton Bays building, or are thinking about buying one, its value depends on what the County allows it to become as well as what stands there today. James R. McLauchlen Real Estate combines certified appraisal with brokerage, and we can walk you through how septic capacity and the town's sewer timeline bear on a particular property. Request a Valuation & Consultation.
