What contaminants are in ROCKY HILL tap water?

Public data sources identify the following contaminants in ROCKY HILL's water supply: Haloacetic acids (HAA9), Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Trichloroacetic acid, Chloroform, Bromodichloromethane, Dichloroacetic acid, Chromium (hexavalent), Chlorate, Dibromochloromethane, Dibromoacetic acid, Nitrate, Nitrate and nitrite, Manganese, Vanadium, Monochloroacetic acid, Barium, Strontium, 4-Androstene-3,17-dione, Fluoride, Nitrite. Levels and comparison to EWG health guidelines are listed on the full city page.

Which water utility serves ROCKY HILL?

ROCKY HILL is served by METROPOLITAN DISTRICT COMMISSION. METROPOLITAN DISTRICT COMMISSION serves approximately 390,887 residents.

Tap Water Quality Report

Tap water quality in ROCKY HILL, Connecticut

Q: Is the tap water in ROCKY HILL, Connecticut safe to drink?

ROCKY HILL's tap water receives a grade of D (65/100) from TapWaterSafety.org. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline, Haloacetic acids (HAA5) significantly above health guideline, Total trihalomethanes (TTHMs) significantly above health guideline. Grades are based on EPA SDWIS, EPA ECHO, EWG Tap Water Database, and the utility's published Consumer Confidence Report.

Served by METROPOLITAN DISTRICT COMMISSION. 390,887 residents.

Average score 65/100

Utilities 1

Population 390,887

65/100

Below Average

ⓘ How did we get this rating?

Quick answer

Tap water in ROCKY HILL, Connecticut receives a grade of D (65/100) from TapWaterSafety.org. It's served by METROPOLITAN DISTRICT COMMISSION. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?

What's in ROCKY HILL's tap water

Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving ROCKY HILL.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 31.3 ppb, 522x above the EWG health guideline of 0.06 ppb.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 32.3 ppb, 323x above the EWG health guideline of 0.1 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 46.0 ppb, 306x above the EWG health guideline of 0.15 ppb.

Recommended filters for ROCKY HILL

Filters matched to the specific contaminants in ROCKY HILL's water supply.

Carbon block (NSF/ANSI 42 + 53)

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All contaminants detected in ROCKY HILL's tap water

Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →

Contaminant	Detected	EWG US health-based	EPA US legal	EU DWD Europe	WHO global	CA PHG strictest US	Tested sample year	Status
Haloacetic acids (HAA9) Disinfection byproduct	31.3 ppb	0.06	—	—	—	—	—	522× over
Haloacetic acids (HAA5) Disinfection byproduct	32.3 ppb	0.1	60.0	60	—	—	—	323× over
Total trihalomethanes (TTHMs) Disinfection byproduct	46.0 ppb	0.15	80.0	100	—	—	—	306× over
Trichloroacetic acid Disinfection byproduct	24.5 ppb	0.1	—	—	—	—	—	245× over
Chloroform Disinfection byproduct	40.2 ppb	0.4	—	—	—	—	—	100× over
Bromodichloromethane Disinfection byproduct	4.34 ppb	0.06	—	—	—	—	—	72× over
Dichloroacetic acid Disinfection byproduct	7.62 ppb	0.2	—	—	—	—	—	38× over
Chromium (hexavalent) Heavy metal	0.0338 ppb	0.02	—	—	—	—	—	1.7× over
Chlorate Disinfection byproduct	113.5 ppb	210.0	—	—	—	—	—	Below guideline
Dibromochloromethane Disinfection byproduct	0.0514 ppb	0.1	—	—	—	—	—	Below guideline
Dibromoacetic acid Disinfection byproduct	0.0131 ppb	0.03	—	—	—	—	—	Below guideline
Nitrate Inorganic	0.043 ppm	0.14	10.0	11.3	11.3	10	—	Below guideline
Nitrate and nitrite Inorganic	0.0369 ppm	0.14	10.0	11.3	11.3	10	—	Below guideline
Manganese Heavy metal	1.88 ppb	100.0	—	50	80	—	—	Below guideline
Vanadium Other	0.0965 ppb	21.0	—	—	—	—	—	Below guideline
Monochloroacetic acid Disinfection byproduct	0.204 ppb	53.0	—	—	—	—	—	Below guideline
Barium Heavy metal	1.5 ppb	700.0	2000.0	—	1300	2000	—	Below guideline
Strontium Radiological	0.0194 ppb	1500.0	—	—	—	—	—	Below guideline
4-Androstene-3,17-dione Other	0.083 ppt	—	—	—	—	—	—	Below guideline
Fluoride Inorganic	0.298 ppm	—	4.0	1.5	1.5	—	—	Below guideline
Nitrite Inorganic	0.00407 ppm	—	1.0	—	—	—	—	Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.