Who Owns the Water Service Line in Portsmouth, NH?
In Portsmouth, water service line responsibility is split at a valve. The City’s water system owns the line from the water main to the shutoff valve. The property owner owns the line from that valve to the water meter.
This guide explains what that split means for leaks, materials, contacts and repairs, using the City’s own published information.
Call (844) 442-1700 if you believe a leak is on the customer-side section of your line and want help locating it.
Who Owns the Water Service Line in Portsmouth?
Ownership is shared between the City and the property owner. Neither party owns the whole pipe from the street to your faucet.
The utility side runs from the water main to the shutoff valve. The customer side runs from the shutoff valve to the water meter. Everything after the meter is also part of the building’s private plumbing.
This is a Portsmouth rule. Dover, Exeter, Rye, Hampton and other nearby systems publish their own boundaries, and those can differ.
What the City Says About the Ownership Split
The City’s Water Division describes the arrangement as “split ownership” on its service line inventory page. That page says the water system owns a portion “from the water main to the shutoff valve” of each line.
The same page says “the property owner owns a portion (from the shutoff valve to their water meter)” of the line.
Source: City of Portsmouth — Water Service Line Inventory, reviewed October 2026.
The City’s November 17, 2025 notice FAQ calls this dividing point the “curb-stop valve” in its explanations. Crews excavate it to check material on both sides.
If your property’s layout is unusual, ask the Water Division which valve marks the boundary for your address.
Source: City of Portsmouth — FAQs on Service Line Notices, dated November 17, 2025.
From Water Main to Shutoff: Utility Side
The utility side begins at the public water main, usually under the street. It continues to the shutoff valve, often called the curb stop.
This portion belongs to the City’s water system. Problems on it are a matter for the Water Division, not a private contractor working on your behalf.
Signs that may point toward the utility side include:
- Water surfacing in the street or near the curb.
- Water bubbling from a valve box cover.
- A wet strip along the sidewalk with no source on your lot.
- Several neighbors reporting pressure loss at once.
These clues are suggestive, not conclusive. Report them to the Water Division and let it determine where the water is coming from.
From Shutoff to Meter: Customer Side
The customer side runs from the shutoff valve to the meter. Where the meter is inside the building, this section may include buried pipe across the yard and a foundation entry.
The property owner owns this section. That generally makes the owner responsible for arranging leak location and repair on it.
Typical features on the customer side include:
- Buried pipe running under lawn, walkway or driveway.
- The point where the line passes through the foundation wall.
- Any fittings or valves between the foundation and the meter.
The exact route, depth and material vary from property to property. Older lots may also have been modified over time.
Where the Meter May Be Located
Many Portsmouth properties have the meter indoors, often in a basement or utility area near where the line enters. Some buildings use other arrangements.
Knowing where your meter sits tells you how much private pipe lies between the boundary valve and the meter. That buried stretch is the part most likely to be overlooked.
If you cannot find your meter, check near the foundation wall facing the street. Do not open sealed utility enclosures or disturb meter fittings to look.
Why the Boundary Matters When Water Escapes
The boundary decides who should act first. It also influences who arranges and pays for location and repair.
A leak on the utility side is the City’s to address. A leak on the customer side is generally the owner’s to address. A leak after the meter is part of the building’s plumbing.
Calling the right party first saves time. It also avoids paying a contractor to investigate pipe that belongs to the utility.
Customer Responsibility Is Not a Leak Diagnosis
Knowing who owns a section does not tell you where a leak is. Ownership rules describe responsibility, not the physical cause of wet ground or a high bill.
Wet soil near your foundation could come from rain, a downspout, a drain line or a supply leak. Only investigation can separate those possibilities.
Treat the ownership split as a map of responsibility. Then gather evidence before concluding that your section has failed.
What to Do if the Leak Is Near the Street
If water appears near the curb, sidewalk or street, contact the Water Division first. Those areas are more likely to involve the utility side or the public main.
Steps that help:
Keep people and vehicles away from soft or collapsing ground.
Photograph the area from a safe distance.
Note when you first saw the water and whether it is growing.
Call the Water Division and describe the location precisely.
Do not dig, probe or open the valve box yourself.
The City lists the Water Division at (603) 427-1530, 680 Peverly Hill Road. Its published office hours are weekdays, 7:30 a.m. to 3:30 p.m. Confirm current hours and after-hours instructions with the City.
What to Do if Water Is Appearing on Your Property
Water appearing on your lot, away from the street, may involve the customer-side line. It may also have nothing to do with the supply line at all.
Start with simple observations:
- Does the wet area persist in dry weather?
- Is it along the likely path from the street to your meter?
- Does your meter move when all fixtures are off?
- Has water pressure changed indoors?
Our guide explains how to check your water meter for leaks and what that test can and cannot show. A leak before the meter may not register on it.
How to Contact the Water Division Appropriately
The Water Division handles water service, meters and the utility side of the line. Contact it for questions about the boundary, your meter or suspected leaks near the street.
When you call, have your service address, account details and a short description ready. Photos and meter readings make the conversation more productive.
For questions about the service line inventory dashboard, the City’s FAQ lists a dedicated contact. Use the City’s pages for current names and numbers, since staff assignments can change.
When a Private Contractor May Be Needed
A private contractor is usually needed when the problem is on the customer side or inside the building. That includes locating a buried leak between the shutoff and the meter.
You may also need a contractor if the City asks you to replace your portion of the line. The City’s FAQ says owners with galvanized lines requiring replacement should use a contractor qualified under Water Division standards.
That contractor coordinates inspections and the curb-stop connection with the Water Division. Confirm qualifications directly with any contractor before work begins.
Call (844) 442-1700 to be connected with an independent local provider for customer-side leak location.
Service-Line Material and the City Inventory
Portsmouth keeps an inventory of service line materials. It was built as part of federal and state lead-and-copper requirements.
At the time we reviewed the page in October 2026, the City reported about 8,400 water services. Of 8,340 customer-side portions, 7,883 had been identified with material types. That left 457 private lines with “no accurate records” at the time.
These are counts of pipe-material records, not counts of leaks. Source: City of Portsmouth — Water Service Line Inventory, reviewed October 2026.
The City says it “has no records of lead service lines having been installed” in its system. It also says “it is still possible that lead service lines, or galvanized pipes with lead components, may exist” today.
Known, Unknown, and Galvanized Line Terminology
The inventory uses status words that are easy to misread. None of them, on its own, says a line is leaking.
| Term | What it means | What it does not mean |
|---|---|---|
| Known material | Records identify the pipe material | The pipe is in good condition |
| Unknown | No accurate record of material | The pipe is lead or galvanized |
| Galvanized requiring replacement | Confirmed galvanized line flagged for replacement | The pipe is actively leaking |
| No identified lead | No lead line found so far | Lead is impossible at every address |
The City’s lead and copper page, updated November 2025, reported 131 galvanized service lines located at that time. Treat that figure as dated, and as a material count rather than a leak count.
Source: City of Portsmouth — Lead and Copper, updated November 2025.
Why Published Inventory Counts Change
Inventory counts move as the City inspects lines and owners report materials. A number that was accurate last year may not be accurate now.
Counts change when:
- Crews excavate curb stops and confirm materials.
- Owners submit photos identifying their own pipe.
- Lines are replaced and records are updated.
- Records are corrected after field checks.
Use published counts as context, not as facts about your property. Your address record is what matters.
How to Verify Information for Your Address
The City offers a Water Service Line Dashboard. It lets residents view a location’s service line materials according to the City’s current records.
The City also publishes an “Identify Your Own Service Line” guide. If your record is unknown, you may be able to help identify the material.
If you receive a notice letter, read which category it names. The FAQ explains that an “unknown at curb-stop valve” letter requires no action, while an “unknown” letter invites you to schedule an inspection or report the material yourself.
Difference Between Leak Location and Replacement
Locating a leak and replacing a line are separate jobs. One finds where water escapes. The other changes the pipe itself.
A leak on the customer side might be repaired at one spot. A line flagged for material replacement may need replacing even without a leak.
For buried leak location, see underground water line leak detection. For repair and replacement choices, see underground water line repair.
What Permits or Utility Coordination May Apply
Repair or replacement work may require permits and coordination. Portsmouth’s Inspection Department accepts plumbing permit applications online.
Work at the boundary may also need Water Division involvement. The City’s FAQ says a qualified contractor coordinates inspections and the curb-stop connection with the Water Division for replacements.
The Inspection Department lists (603) 610-7243 for permit questions. Not every leak investigation requires a permit, so ask before assuming.
Source: City of Portsmouth — Inspection Department Permit Applications, reviewed October 2026.
Comparing Responsibility Scenarios
Use these tables to decide who to call first. They describe typical responsibility under Portsmouth’s published split, not a legal ruling for every property.
| Line segment | Typical responsible party | Who to call |
|---|---|---|
| Public water main | City water system | Water Division |
| Main to shutoff valve | City water system | Water Division |
| Shutoff valve to meter | Property owner | Private leak detection or plumbing provider |
| Meter and meter fittings | Ask the Water Division | Water Division |
| After the meter, inside the building | Property owner | Plumber or leak detection provider |
| Question | Main to shutoff | Shutoff to meter |
|---|---|---|
| Who owns it? | City water system | Property owner |
| Typical location | Under street or near curb | Under yard, walkway or drive |
| First call for a suspected leak | Water Division | Private provider, after ruling out utility side |
| Who arranges repair? | City | Property owner |
| Should the owner dig or operate valves? | No | Only through a qualified contractor |
When the leak location is unclear, start with the Water Division. It can help determine whether the utility side is involved.
What to Ask Before Excavation Starts
Excavation is disruptive, so ask questions first. Clear answers protect your yard, your budget and your relationship with the utility.
- Has the leak been located, or only suspected?
- Is the work entirely on the customer side?
- Has the Water Division been consulted where needed?
- Have underground utilities been marked before digging?
- Is a permit required, and who obtains it?
- What restoration is included, and what is separate?
For a walk-through of how calls are handled, see how it works.
Documents and Photos Worth Keeping
Good records help with future sales, insurance questions and repeat problems. They also make utility conversations easier.
Keep:
- Any City notice letters about your service line.
- A screenshot of your address on the City dashboard.
- Photos of the line where it enters the building.
- Written findings from any leak investigation.
- Permits, inspection results and repair invoices.
- Notes on dates, calls and who you spoke with.
Call (844) 442-1700 when you are ready to have a customer-side leak investigated.
Frequently Asked Portsmouth Line Questions
Does the City own the whole pipe to my house?
No. The City says the water system owns the line from the main to the shutoff valve. The owner owns the line from that valve to the meter.
If a leak is on my side, do I have to arrange the repair?
Generally, yes. The customer-side section belongs to the property owner, so the owner typically arranges location and repair.
Does an “unknown” line mean my pipe is lead?
No. Unknown means the City lacks an accurate record of the material. It does not mean the pipe is lead or galvanized.
Is a galvanized service line automatically leaking?
No. Galvanized describes the material, not its condition. A galvanized line may still be flagged for replacement under the City’s program.
Who do I call if water is coming up near the curb?
Call the Portsmouth Water Division first. Areas near the curb or street are more likely to involve the utility side.
Can I look up my service line material online?
Yes. The City offers a Water Service Line Dashboard showing materials according to its current records.
Do Dover, Exeter, Rye and Hampton use the same rule?
Not necessarily. Each system publishes its own boundary, so check the rules for the utility that serves your address.