Plaistow Water Dept
What EPA’s and CDC’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals, plus violations since 2016, with the certification that handles each result.
- Serves
- 465 people
- Connections
- 102
- Water source
- Surface water bought from another system
- Based in
- Plaistow, NH
- County
- Rockingham
- Owner
- Local government
The ZIP code it serves
The short answer
1 result is above EPA’s legal limit. The worst: Haloacetic acids (HAA5), above the legal limit. 4 health-based violations since 2016.
What was found
Haloacetic acids (HAA5) and total trihalomethanes (TTHM): New Hampshire’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2023.
Above the legal limit1
Haloacetic acids (HAA5)
Forms or is added in treatment
57.8ppb
Highest yearly average, 2023
Averaged by year, the highest was 57.8 ppb, in 2023, below EPA’s legal limit of 60 ppb. That is the only year on file. EPA judges this limit at each sampling point, and recorded violations for haloacetic acids (HAA5) at this utility in 2022 and 2023.
What handles it
No certification claim covers this compound yet.
Below EPA’s limits1
Total trihalomethanes (TTHM)
Forms or is added in treatment
48.7ppb
Highest yearly average, 2023
Averaged by year, the highest was 48.7 ppb, in 2023, below EPA’s legal limit of 80 ppb. That is the only year on file.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2023 to Sept. 30, 2023 | 0.072 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2023 to June 30, 2023 | 0.076 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2023 to March 31, 2023 | 0.093 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2022 to Dec. 31, 2022 | 0.14 MG/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. | ||||
What this report can’t tell you
Everything else. Haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are New Hampshire’s yearly averages as CDC publishes them, from 2023 on, with EPA’s national file for 2012 to 2019. Plaistow Water Dept’s own annual report, which it must send you every year, has the contaminants this page does not show.
Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.
Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; CDC’s yearly averages for New Hampshire cover 2023.
Testing your own tap
The 3 labs New Hampshire certifies closest to the area Plaistow Water Dept serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Eurofins Derry
Derry, NH · about 10 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, PFAS
Nelson Analytical LLC
Manchester, NH · about 18 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts
Seacoast Analytical Services LLC
Lee, NH · about 21 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
Sources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- CDC Environmental Public Health Tracking Network, yearly averages New Hampshire supplied to CDC, 2020 to 2023, read Oct. 8, 2026. TapBuff’s comparisons with EPA’s limits are its own, not CDC’s or New Hampshire’s.
- Certified labs: New Hampshire ELAP, drinking water labs, as listed in TNI LAMS, read Oct. 13, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID NH1931010. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on Haloacetic acids (HAA5)What each one does to health, where it comes from, and the certification claim that addresses it.About Haloacetic acids (HAA5)
- Get the utility’s own reportPlaistow Water Dept must send you a water quality report every year. It covers contaminants this page does not show.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded