Tap water · MA
Boston Water and Sewer Commission
EPA system ID MA3035000 · serves about 675,647 people. Every US utility must publish an annual water quality report — here’s the official one (2025), and below it, our plain-English translation.
Read the official report →What Boston Water and Sewer Commission found in 2025
12 detected analytes from the utility’s own annual report, hand-normalized — 1 was near or over a limit (flagged below).
| Detected | Level | Limit | % of limit | Status |
|---|---|---|---|---|
| Lead (90th percentile) | 22.5 ppb | 15 ppb | 150% | Over limit |
| Monochloramine | 1.99 ppm | 4 ppm | 50% | Within limit |
| Haloacetic Acids-5 | 15.8 ppb | 60 ppb | 26% | Within limit |
| Total Trihalomethanes | 16.1 ppb | 80 ppb | 20% | Within limit |
| Fluoride | 0.71 ppm | 4 ppm | 18% | Within limit |
| Radium-226 | 0.82 pCi/L | 5 pCi/L | 16% | Within limit |
| Copper (90th percentile) | 96.6 ppb | 1,300 ppb | 7% | Within limit |
| Nitrate^ | 0.64 ppm | 10 ppm | 6% | Within limit |
| Nitrite | 0.005 ppm | 1 ppm | 1% | Within limit |
| Barium | 0.008 ppm | 2 ppm | 0% | Within limit |
| Sodium | 35.6 mg/L | — | — | No federal limit |
| Turbidity (highest) | 0.67 NTU | — | — | No federal limit |
Levels and limits are as printed in the utility’s report (“limit” is the EPA MCL, action level, residual limit, or secondary guideline that applies to that row; “ND” = not detected). Utilities publish these reports annually — we re-check every covered utility each July, after the federal publication deadline. Detected doesn’t mean dangerous — most detections sit far below their limits. This is education, not medical advice.
Your tap, if it were a bottle
How Boston Water and Sewer Commission water stacks up against the bottled aisle
Same minerals, same units — the tap values below come from the utility’s report, placed next to the closest match in our bottled-water database.
| Mineral | Your tap | Closest bottled match |
|---|---|---|
| Sodium | 35.6 mg/L | San Pellegrino at 32 mg/L |
Tap values are the headline levels from the utility’s annual report (often a highest or average figure); bottled values are label- or report-derived. A closest match is a numeric comparison, not an equivalence or an endorsement.
Zip codes covered
02108 · 02109 · 02110 · 02111 · 02113 · 02114 · 02115 · 02116 · 02118 · 02119 · 02120 · 02121 · 02122 · 02124 · 02125 · 02126 · 02127 · 02128 · 02129 · 02130 · 02131 · 02132 · 02134 · 02135 · 02136 · 02163 · 02199 · 02210 · 02215
Boundary zips partially served by other systems are deliberately unlisted — check your exact zip.