In the winter of 2022, homeowners along Old Lane Extension in Montville started finding wooden stakes driven into their yards. A letter followed, explaining what the stakes marked: the path of a new sewer lateral that would soon replace the septic system many of these houses had relied on for decades. Construction crews spent the following year digging trench by trench uphill toward Abbott Road, testing each new line before certifying it. By the time the Township Committee passed a resolution accepting the work into the public utility, 96 homes that had spent their entire history on private septic fields were connected to Montville's municipal sewer system.
That project tells you something most listing sheets won't: in Montville, whether a house runs on public sewer or a private septic system has almost nothing to do with the street it sits on, the price it's asking, or which of the township's three historic villages it belongs to. It has to do with when, if ever, a sewer line reached that particular block. For a buyer comparing two houses that look identical on paper, that single fact changes the inspection checklist, the closing timeline, and what you should be asking before you write an offer.
Two Systems, One Town, Two Different Footprints
Montville Township is built from three formerly separate villages, Montville, Towaco, and Pine Brook, and it's easy to assume utility service follows those boundaries or follows price. It doesn't. According to the township's own numbers, public water reaches roughly 6,000 homes and public sewer reaches roughly 6,500. Those are close figures, but they aren't the same 6,000 or 6,500 homes. A property can sit on municipal sewer and still draw its drinking water from a private well, or the reverse. The two systems were built out separately, on separate timelines, and a buyer who confirms one and assumes the other is guessing.
The township's Water Pollution Control Authority services around 4,600 sewer connections, concentrated along the Route 32 corridor and the developments built up around it, and sewer service didn't arrive in town at all until the 1970s. Everything built or subdivided before that infrastructure reached a given block was put on septic by default, and a meaningful share of those systems are still there.
Why Some Blocks Convert and Others Wait
The mechanism behind that patchwork is worth understanding because it explains why your street might be next in line for a sewer connection, or might not be for a very long time. Montville doesn't own unlimited sewer capacity. Its flow rights are granted by the Parsippany-Troy Hills Sanitary Sewer Utility, and the township's own sewer ordinance is direct about what that means in practice: flow rights are finite, they aren't guaranteed, and sewer permit applications are approved on a first-come, first-served basis. When a developer or a group of homeowners wants a new connection and the township doesn't have spare capacity on hand, someone has to negotiate for more flow rights and pay for them.
That's the quiet reason conversions happen block by block instead of all at once. It isn't that some neighborhoods are prioritized and others ignored. It's that capacity is a resource the township allocates as it becomes available, and township data shows the demand has been building for a long time: since 1995, Montville has seen a 53 percent increase in the gallons of sewage it treats daily, driven by a 41 percent rise in the number of sewer customers. That growth came from both new construction and, in the township's own words, "connections by those with obsolete septic fields." In other words, the shift from septic to sewer in Montville isn't a historical footnote. It's still happening, one flow-rights allocation at a time.
How a Conversion Actually Plays Out
The Old Lane project is useful because it shows what that process looks like on the ground, not just in an ordinance. The township financed the work with roughly $2.5 million in low-rate loans from the New Jersey Water Bank, a program jointly run by the NJDEP and the New Jersey Infrastructure Bank, and the savings versus financing it alone came to an estimated $561,013 over the 30-year loan term, about 23 percent of the total project cost. The construction itself moved through a defined sequence:
- Utility mark-outs and notification to affected residents before any excavation
- Trenching and installation of new sewer mains and individual laterals up to each property line
- Testing of the completed lines to confirm they hold
- Certification by the project engineer
- Formal acceptance by the Township Committee via public resolution
- A notification letter to each homeowner authorizing the actual connection
That sequence matters for a buyer because it means "the sewer is coming" and "the sewer is here" are two very different statements, separated by a process that can run over a full construction season. If you're looking at a house on a street where a similar project is underway, ask which stage it's in before you assume anything about its current utility status.
Before You Write the Offer
A septic or sewer question is easy to overlook because it rarely shows up as its own line item in a listing description. Before you submit an offer on a Montville property, it's worth confirming:
- Whether the home is on public sewer, private septic, or a combination where wastewater and drinking water are handled by two different systems
- If it's on septic, when the system was last pumped and inspected, and whether any repairs or replacements are on record with the township
- If it's on a private well, whether a Private Well Testing Act sample has been pulled recently, since state law requires that test to be completed and shared with both parties before closing
- Whether the street or block has been part of, or is scheduled for, a sewer extension project, which you can ask about directly through Montville's Water and Sewer Department
- Whether the seller has any correspondence from the township about flow rights, connection requirements, or upcoming assessments tied to the property
None of this shows up automatically in an MLS listing. It shows up when someone asks.
What Either Path Costs
The costs attached to each system are different enough to affect your budget, not just your due diligence checklist. A septic inspection tied to a real estate transaction typically runs somewhere in the range of $500 to $2,000, and if the system fails that inspection, a full replacement can run $15,000 to $35,000 depending on soil conditions and system size. For homes on private wells, New Jersey's Department of Environmental Protection has estimated average testing costs in the $450 to $650 range, though private labs quoting the full Private Well Testing Act panel sometimes come in closer to $1,200 to $1,500 depending on the parameters tested and how the sample is collected. Either way, the law is clear that the seller and buyer must both review the results before the closing can proceed.
None of these numbers are large enough to derail a well-priced house in Montville. What derails a closing is finding out about a failed system, or a well that hasn't been tested, after you're already under contract and working against a deadline.
The Real Line in Montville
The dividing line that actually matters when you're comparing two Montville houses isn't Towaco versus Pine Brook, and it isn't which side of Route 202 a property sits on. It's whether a sewer main ever reached that block, and whether the well or septic system serving it has been maintained the way state law and township code expect. That line runs down the middle of streets, not around neighborhoods, and the only way to know which side a specific house falls on is to ask before you write the offer, not after.
A Few Questions Worth Asking Directly
How do I find out before making an offer whether a specific Montville house is on septic or sewer? Ask your agent to confirm it directly with the seller or with Montville's Water and Sewer Department, which handles both municipal water and sewer accounts. If the street has been part of a recent NJ Water Bank funded project, the township's project pages document exactly which homes were included and when.
If my future street is scheduled for a sewer conversion, does that mean the septic system is currently failing? Not necessarily. Township data attributes sewer growth to both new construction and voluntary connections by homeowners with aging systems, so a scheduled conversion doesn't automatically mean a system has already failed. It's still worth asking for maintenance records during due diligence.
If a house has public sewer, do I still need to worry about well water testing? Yes, if it draws drinking water from a private well. Sewer and water are separate systems in Montville, evidenced by the gap between the roughly 6,000 homes on public water and the roughly 6,500 on public sewer. Confirm both independently rather than assuming one implies the other.
If you're weighing a house in Montville and want someone who will actually run down its sewer and septic history before you write an offer, reach out to Michael Gabriel. Getting that answer early is a lot cheaper than getting it during attorney review.
