Dighton Water District was over the limit for a chlorine byproduct in 8 of 12 quarters, federal records show
The district's own notices traced the problem to its South Fire Station sampling site on Main Street and, in 2024, estimated it would be back in compliance by that winter.
DIGHTON The Dighton Water District was over the state and federal limit for trihalomethanes, a group of chemicals that form when chlorine reacts with natural material in water, in eight of the 12 quarters from July 2023 through June 2026, a South Coast 360 count of U.S. Environmental Protection Agency drinking water violation records shows.
The limit is 80 parts per billion, figured as a running average of the past year's samples at each testing site, and EPA's records code all eight violations as health based. The district's own notices say that some people who drink water over the limit "over many years may experience problems with their liver, kidneys, or central nervous system, and may have an increased risk of getting cancer," and that the problem is not an emergency.
EPA's database lists a trihalomethane violation for every quarter from July 2023 through December 2024, none for 2025, and violations again for January through March and April through June 2026, the most recent quarter in the records, for a system EPA lists as serving 5,280 people. EPA classes each one as a Tier 2 violation, which federal rules say customers must be told about within 30 days.
The district's reports name the Dighton South Fire Station at 300 Main Street as the sampling site over the limit, where the running average was 81 parts per billion in August 2023 and reached 143.5 in October and November 2023, then 110 in February 2024, 100 in May and August 2024 and 83 in November 2024. In its report on 2025 water, the district lists a highest trihalomethane result of 102 parts per billion, with results from 36.7 to 102, and marks the limit as violated, though EPA's records list no trihalomethane violation for that year.
South Coast 360 reached out to Superintendent Ernie Bacon and the state Department of Environmental Protection, who did not answer by publication.
What the district says it has done
In its notices, the district says it installed mixers in the Elm Street and Williams Street storage tanks in 2015 to keep water from sitting, runs a spring and fall unidirectional flushing program, and took the Elm Street tank offline on June 5, 2024, which it said would cut the time water sits in the Williams Street tank to seven days in summer and 40 days in winter. A notice for the July to September 2024 quarter said: "We anticipate resolving the problem and being back in compliance with an estimated time of Winter 2024."
The district's report on 2024 water said its engineers, Woodard & Curran, "recommended a possible aeration unit at the Williams St Water Storage tank" if flushing and keeping the Elm Street tank offline could not hold the district in compliance, and EPA's records list the violations returning in 2026 after a year without one.
In October 2025 a Woodard & Curran engineer presented commissioners a design report for rehabilitating the Williams Street and Elm Street tanks, with a first-year cost of $2.257 million that "will need to be borrowed" and $115,000 a year in ongoing costs that could come out of the district budget, according to the commissioners' Oct. 14, 2025, minutes.
On May 12, 2026, commissioners voted 2-0 to put a second contract amendment, for added engineering services on the Williams and Elm Street tank rehabilitation, on the annual district meeting warrant, and district voters approved $30,000 for it unanimously at the annual meeting May 28, the minutes of both meetings show.
The report on 2025 water lists one other violation, for a quarterly manganese sample the district did not collect in the last three months of 2025, and says the district took its next manganese sample in January 2026.
What residents can do
- The district's notices say people who are pregnant, may become pregnant or give tap water to young children can choose to limit how much tap water they use, for example by using bottled water or by letting water sit in a pitcher overnight so the chemicals can evaporate, and that home water filters can reduce exposure.
- The notices say the federal Centers for Disease Control and Prevention recommends that nursing mothers keep breastfeeding.
- Questions about the system go to the district office, 192 Williams Street, North Dighton, 508-824-9390. Questions about the rules go to MassDEP's Drinking Water Program, program.director-dwp@mass.gov or 617-292-5770, and health questions to the state Department of Public Health, 617-624-5757.
Label: Reported by us, from the town's posted records.
Notes
Every fact comes from EPA's Safe Drinking Water Information System violation and water system records for the Dighton Water District, the federal Tier 2 public notice rule, the district's water quality reports for 2023, 2024 and 2025 and the public notices printed with them, and the minutes of the commissioners' meetings of Oct. 14, 2025 and May 12, 2026 and the annual district meeting of May 28, 2026. The count of eight of 12 quarters is ours, from EPA's quarterly records. South Coast 360 reached out to Superintendent Ernie Bacon and MassDEP, who did not answer by publication; their answers will be added when they come.
Corrections
No corrections to this story. If something here is wrong, tell us. Every correction is dated on the story and listed in our public log.
Sources (9)
- U.S. EPA Safe Drinking Water Information System, violations for Dighton Water District (MA4076000)U.S. EPA. Contaminant code 2950 (total trihalomethanes), health based, public notice tier 2, for each quarter July 2023 to December 2024 and January to June 2026; none for 2025; a manganese monitoring record for October to December 2025. Reopened Nov. 11, 2026.
- U.S. EPA Safe Drinking Water Information System, community water systems in DightonU.S. EPA. Dighton Water District, population served 5,280. Reopened Nov. 11, 2026.
- 40 CFR 141.203, Tier 2 public noticeFederal rule. Tier 2 notice no later than 30 days after the system learns of the violation. Reopened Nov. 11, 2026.
- Dighton Water District, Consumer Confidence Report 2025 (PWS ID 4076000)Dighton Water District. TTHM highest 102 ppb, range 36.7 to 102, LRAA limit 80, violation Y; manganese monitoring violation for the fourth quarter of 2025, sampled January 2026; Superintendent Ernie Bacon, 192 Williams Street, 508-824-9390. Reopened Nov. 11, 2026.
- Dighton Water District, Consumer Confidence Report 2024 with quarterly TTHM public noticesDighton Water District. LRAA at the Dighton South Fire Station, 300 Main Street: 110 (Feb. 6, 2024), 100 (May 9), 100 (Aug. 1), 83 (Nov. 18); corrective actions; Elm Street tank offline June 5, 2024; Woodard and Curran aeration recommendation; "Winter 2024" estimate; health language and what residents can do. Reopened Nov. 11, 2026.
- Dighton Water District, Consumer Confidence Report 2023 and public notice (dated June 21, 2024)Dighton Water District. LRAA 81 (Aug. 8, 2023) and 143.5 (Oct. 17 and Nov. 21, 2023) at the South Fire Station; mixers installed 2015. Reopened Nov. 11, 2026.
- Dighton Water District Board of Commissioners minutes, Oct. 14, 2025 (scanned)Dighton Water District. Woodard and Curran Williams and Elm Street tank design basis report: year one cost $2.257 million to be borrowed, $115,000 a year that could come out of the district budget. Reopened Nov. 11, 2026 from the page images.
- Dighton Water District Board of Commissioners minutes, May 12, 2026 (scanned)Dighton Water District. Vote 2-0 to put contract amendment number 2 for the Williams and Elm Street tank rehabilitation on the annual district meeting warrant. Reopened Nov. 11, 2026 from the page images.
- Dighton Water District annual district meeting minutes, May 28, 2026 (scanned)Dighton Water District. Article 10, $30,000 for Professional Engineering Services Amendment #2 for Williams Street and Elm Street tank rehabilitation, carried by unanimous vote. Read Nov. 11, 2026 from the page images.