B70/100
WATERTOWN WATER DEPT. (MWRA) — Water Quality Report 2026
Serving 35,329 people · Massachusetts
Water Source
Purchased Surface Water
County
—
System ID
MA3314000
Violations
7
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.001 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
1
Unresolved
0
Health-Related
TIER 3Unresolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: August 1, 2021 – August 31, 2021Rule: Total Coliform RuleEnforcement: Formal — state order issuedVerify on EPA.gov
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About WATERTOWN WATER DEPT. (MWRA)
Is WATERTOWN WATER DEPT. (MWRA) water safe to drink?
WATERTOWN WATER DEPT. (MWRA) water receives a grade of B (70/100), which is considered good. Out of 76 contaminants tested, none exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has WATERTOWN WATER DEPT. (MWRA) detected?
76 contaminants were tested in WATERTOWN WATER DEPT. (MWRA)'s water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does WATERTOWN WATER DEPT. (MWRA) have any EPA violations?
Yes, WATERTOWN WATER DEPT. (MWRA) has 7 EPA violation(s) on record, with the most recent in 2021. Violation types include MON, TT, MR. 5 are health-based violations.
How many people does WATERTOWN WATER DEPT. (MWRA) serve?
WATERTOWN WATER DEPT. (MWRA) serves approximately 35,329 people, Massachusetts. The system provides water to 1 community: Watertown.
What type of water does WATERTOWN WATER DEPT. (MWRA) provide?
WATERTOWN WATER DEPT. (MWRA) sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is MA3314000.
How does WATERTOWN WATER DEPT. (MWRA) compare to other utilities in Massachusetts?
WATERTOWN WATER DEPT. (MWRA) scores 70/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Massachusetts state page for a full comparison of water systems.