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Tap water quality report

Harwich, MA

EPA monitoring detected 16 contaminants across the 1 water supplier serving Harwich. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

1
water supplier
39,144
people served
16
contaminants found
Massachusetts rankings Lead in Massachusetts PFAS in Massachusetts

What was found in Harwich's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
2700 µg/L 27%
of the EPA limit 10000 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Copper
250 µg/L 19%
of the EPA limit 1300 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Barium
17 µg/L 0.9%
of the EPA limit 2000 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2018
1/1 SYR4
TTHM
12.4 µg/L 16%
of the EPA limit 80 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Dibromochloromethane
4.4 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Bromoform
4.1 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Selenium
4 µg/L 8%
of the EPA limit 50 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2018
1/1 SYR4
Total Haloacetic Acids (HAA5)
3.41 µg/L 5.7%
of the EPA limit 60 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Bromodichloromethane
2.7 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Dibromoacetic Acid
2.64 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Toluene
2.4 µg/L 0.2%
of the EPA limit 1000 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Chloroform
2.145 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Arsenic
2 µg/L 20%
of the EPA limit 10 µg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2018
1/1 SYR4
Dichloroacetic Acid
1.065 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Monobromoacetic Acid
0.5000 µg/L
No EPA limit set
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2019
1/1 SYR4
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
Main supplier: HARWICH WATER DEPARTMENT · 39,144 people · 2024
1/1 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Harwich

SupplierPopulation served
HARWICH WATER DEPARTMENT 39,144

Frequently asked questions about Harwich tap water

Is Harwich tap water safe to drink?

EPA testing detected 16 contaminants in the water serving Harwich. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Harwich?

1 public water supplier report drinking-water monitoring for Harwich, Massachusetts to the EPA. Each is listed above with its population served.

What contaminants are in Harwich's water?

The contaminants EPA monitoring detected in Harwich include Nitrate, Copper, Barium, TTHM, Dibromochloromethane. The full list, with the level at the main supplier and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.