Town of Southwest Harbor · Water & Wastewater
Southwest Harbor Water and Sewer: What’s in Your Water, and Who to Call
Where our tap water comes from, what the latest testing found, how the wastewater plant is performing, and who is actually responsible for each of these things. All figures on this page are dated and linked to their original source.
Start Here
The Water & Sewer District is not the Town
This is the most common point of confusion, and it matters when you need help. Water and sewer service in Southwest Harbor is provided by the Southwest Harbor Water & Sewer District, a separate quasi-municipal utility created by a special act of the Maine Legislature. It has its own trustees, its own budget, and its own billing. Rates are set under Maine Public Utilities Commission authority in Title 35-A, Chapter 61 — not by Town Meeting. [1]
Contact the District
26 Village Green Way
P.O. Box 1100
Southwest Harbor, ME 04679
Phone: (207) 244-3948
Email: [email protected]
Office Hours
Monday – Thursday
7:00 AM – 3:00 PM
Friday – Sunday
Closed
The office closes briefly for lunch. Call ahead if you are making a trip in.
Who Decides
A board of trustees governs the District and sets rates after public hearing. Current trustees are Lee Worcester (Chairman), Ralph Dunbar (Vice Chair), Ken Minier (Treasurer), Allen Willey, and the Town Manager, Karen Reddersen.
District Manager: Bennett Liscomb
Trustee meetings are held at the Town Office and are open to the public. [2]
Source Water
Our drinking water comes from Long Pond
Water is drawn from Long Pond at a pump station at 118 Long Pond Road, near the headwaters, and treated at the Water Filtration Plant at 89 Long Pond Road. Because much of the watershed lies within Acadia National Park, the land around our source is permanently protected from development — a genuine and unusual advantage.
Maine’s Source Water Assessment rates Long Pond as low risk for bacteria and nitrates, low risk for long-term contaminants, and low risk of future contamination, citing park land ownership as the reason. Notably, the source quality was good enough to qualify for a filtration waiver, and the District filters the water anyway as an added layer of protection. [3]
Delivered in a year
During peak tourist months the system averages 354,838 gallons per day — a summer surge that shapes every capacity decision the District makes.
Stored in three tanks
Storage plus 94 fire hydrants across the system. That stored volume is what fights a structure fire downtown.
On more than 1,000 services
Two Maine-licensed operators run the plant, with continuous SCADA monitoring of the system around the clock.
Test Results
What the most recent testing found
Every public water system in the country must publish an annual water quality report, often called a Consumer Confidence Report. Here is what Southwest Harbor’s most recent one shows. The District reported no violations in 2024. [3]
| What was tested | Result | Legal limit |
|---|---|---|
Lead 10 homes, August 2024 |
2.1 ppb average Range below 0.5 to 4.51 ppb 0 of 10 sites failed |
15 ppb action level |
Copper 10 homes, August 2024 |
0.19 ppm average Range 0.032 to 0.30 ppm 0 of 10 sites failed |
1.3 ppm action level |
PFAS All six Maine-regulated compounds, March 2025 |
Not detected. Every compound measured below the 2.00 ng/L detection limit, including PFOA and PFOS | 4 ng/L for PFOA and PFOS; 10 ng/L for the others |
Bacteria Monthly at two sites, 2024 |
24 samples taken 0 failed |
No detectable coliform |
Trihalomethanes (TTHM) Chlorination byproduct, 2024 |
43 ppb Range 36 to 51 ppb |
80 ppb |
Haloacetic acids (HAA5) Chlorination byproduct, 2024 |
37 ppb Range 24 to 47 ppb |
60 ppb |
Chlorine residual System-wide, 2024 |
0.39 ppm average Range 0.20 to 0.79 ppm |
4 ppm maximum |
If you searched online and got alarmed, read this. Some advocacy databases flag Southwest Harbor’s trihalomethanes and haloacetic acids against their own health guidelines, which are far stricter than federal law. [4] Both are real and both are byproducts of chlorinating surface water — an unavoidable trade-off, since chlorine is what prevents waterborne disease. Our results are comfortably inside legal limits. A legal limit and an advocacy guideline are two different things, and it is worth knowing which one a website is using before you draw a conclusion.
You Can Help
The lead service line inventory needs 150 more answers
Federal rules now require every water system to identify what material each service line is made of — the pipe running from the street into your building. Lead pipe is the concern.
No lead or galvanized pipe requiring replacement has been found so far. About 150 lines remain unidentified — and those are the ones residents can help close out.
If the District has not yet recorded your service line, you can check it yourself in a few minutes. Find where the water pipe enters your basement, before the meter.
- 1
Scratch the pipe with a coin
Use the edge of a key or coin on a small area of the pipe. Do not use a knife or anything that could puncture it.
- 2
Look at the color of the scratch
A shiny silver-grey scratch on a dull grey pipe suggests lead. Copper scratches to a penny-brown color. Galvanized steel stays dull silver and a magnet will stick to it. Plastic is obvious.
- 3
Try a magnet
A magnet sticks to galvanized steel. It will not stick to lead, copper or plastic.
- 4
Report what you found
Call the District at (207) 244-3948 or email [email protected] with your address and what you saw. If you are not confident, say so — they would rather come look than guess.
The next round of lead and copper tap sampling is scheduled for summer 2027, on the District’s three-year cycle.
Sewer Service
What not to put down the drain
The District is direct about this one: disinfecting wipes and products labeled “flushable” are not. They clog sewer lines and damage District pumping equipment, and every blockage is paid for through rates. [2]
Never flush wipes of any kind — including baby wipes, disinfecting wipes, and anything marketed as flushable
No paper towels, tissues or napkins. They do not break down the way toilet paper does
No fats, oils or grease down the sink. Let them cool, then scrape into the trash
No medications. Use a drug take-back rather than flushing them into the harbor
One more thing that surprises property owners: under the District’s enabling law, a “readiness to serve” charge can apply to property abutting District sewer or water mains even when the property is not actually connected. Unpaid water charges can also become a lien that takes precedence over other claims except taxes and sewer rates. If you own unconnected land along a main, it is worth asking the District where you stand. [1]
Wastewater Treatment
The treatment plant, the harbor, and a permit that expires this year
Southwest Harbor’s wastewater treatment facility sits at 9 Apple Lane and discharges treated effluent into the harbor. It operates under federal discharge permit ME0100641, with a design flow of 0.375 million gallons per day. The permit is active, and the plant reports its results to state and federal regulators every month, where anyone can look them up. [5]
Those public records show that in July and August 2025 the plant exceeded its bacteria limits at Outfall 001. Fecal coliform and enterococci were both reported at 2,420 — the laboratory’s upper reporting value — against daily maximum limits of 31 and 54 respectively. July also recorded monthly average exceedances for both. These are measured results, not paperwork errors. No formal enforcement action has been taken. [6]
Context matters in both directions. The receiving water is classified Class SB and was already listed as impaired for bacteria with a cleanup plan required before these exceedances, so the plant is discharging into water that is not meeting its standard. At the same time, state toxicity and chemical evaluations of this discharge found no reasonable potential to exceed water quality criteria for the pollutants they screened. The bacteria numbers are the live issue. [7]
The permit’s effluent limits run through November 30, 2026. Renewal means a public comment period, and it is the one moment when regulators must formally weigh the plant’s recent record against the terms of the next permit. If you care about harbor water quality, that comment window is the highest-leverage opportunity available to a resident — higher than any town vote.
To take part, watch for the draft permit notice from the Maine Department of Environmental Protection, which issues these permits under delegated federal authority. Written comments from residents become part of the record. The District’s own trustee meetings, held at the Town Office, are the place to ask what the plant is doing about the exceedances and what it would cost to fix.
Downstream Effects
Why you cannot dig clams in Southwest Harbor
Water quality in the harbor is not an abstraction — it closes a fishery. Maine’s Department of Marine Resources classifies Southwest Harbor and Norwood Cove as Prohibited for shellfish harvest because of pollution.
The prohibited area covers the shores, flats and waters west of a line beginning at Kings Point, running north to the southwest point of Greening Island, then northwest to the base of the sixth private pier north of the entrance to Norwood Cove. Within it, it is unlawful to dig, take or possess clams, quahogs, oysters, mussels, or whole or roe-on scallops. The designation is area P4 in Growing Area EH, which runs from Seawall in Southwest Harbor to Otter Cove in Mount Desert and includes the Cranberry Isles. The current notice is dated September 13, 2024 and remains in effect until repealed or replaced. [8]
Closures change. Before harvesting anywhere on Mount Desert Island, check the current Department of Marine Resources notice for Growing Area EH and the Town’s Shellfish Committee, rather than relying on what was true last season. [9]
Not on District Water?
Private wells are tested by nobody but you
If your household is on a private well, none of the testing above applies to you. No agency monitors private wells in Maine. The responsibility is entirely the owner’s, and most wells in the state have never been tested for arsenic.
There is also a specifically local reason to pay attention. Southwest Harbor’s Climate Vulnerability Assessment identifies saltwater intrusion into private wells as a hazard for this town as sea level rises — a slow change that shows up as a taste difference long before anything dramatic happens. Read what the assessment found.
Arsenic and uranium, once
Both occur naturally in Maine bedrock and neither has a taste or smell. One test tells you whether you need to act.
Bacteria, every year
Annual bacteria testing is the standard recommendation, and after any flooding, well work, or change in taste or color.
Sodium and chloride, if coastal
These are the markers of saltwater intrusion. If your well is near the shore, they are worth tracking over time rather than testing once.
Where to get a test
Maine’s Drinking Water Program can point you to certified laboratories and explain results. Call (207) 287-2070.
Billing
Rates, bills, and help if you cannot pay
Water and sewer rate schedules are set by the trustees after public hearing and are posted on the District’s website, along with any notice of a rate increase. Because they are revised periodically, always read the current schedule at the source rather than a figure copied elsewhere. [2]
Paying online
The District accepts online payments through its website. Note that a 2.5% portal fee applies to card payments — paying by check or in person at the office avoids it.
If you are behind
Talk to the District before a shutoff notice becomes a disconnection. Maine PUC rules entitle customers to a reasonable payment arrangement on an overdue balance.
PUC Consumer Assistance: (800) 452-4699
Bill assistance
211 Maine can connect households to utility assistance programs. Dial 211 or visit 211maine.org.
Verify It Yourself
Sources
Every figure on this page comes from one of the following. Water quality data is published annually and compliance data monthly, so check the original if you are relying on a number for anything important.
- Maine Legislature — An Act To Create the Southwest Harbor Water and Sewer District (127th Legislature, Private & Special Law ch. 11)
- Southwest Harbor Water & Sewer District — official website, trustees, rates and notices
- 2024 Annual Water Quality Report (Consumer Confidence Report), Southwest Harbor Water & Sewer District
- Environmental Working Group Tap Water Database — Southwest Harbor Water Department, PWS ID ME0091490
- US EPA ECHO — Southwest Harbor WWTF facility report
- US EPA ECHO — discharge monitoring report and effluent violation data, permit ME0100641
- Maine DEP / US EPA — draft discharge permit and fact sheet, ME0100641
- Maine Department of Marine Resources — shellfish classification notice, Growing Area EH
- Town of Southwest Harbor — Shellfish Committee
- Maine Drinking Water Program — private well testing guidance, (207) 287-2070
Last verified August 8, 2026. This page is a resident summary compiled by the Town of Southwest Harbor Environmental Workgroup. It is not an official publication of the Southwest Harbor Water & Sewer District. For questions about your own service, contact the District directly at (207) 244-3948.