Arlington Water Dept. (Mwra), MA
Exceeded the action level in the past
Latest 90th-percentile lead: 2.68 ppb (monitoring period 2023-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
About Arlington Water Dept. (Mwra)
Arlington Water Dept. (Mwra) serves about 46,308 people through 12,765 service connections, which makes it a large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Middlesex County, Massachusetts. EPA system ID: MA3010000; phone on file: 7813163310. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Lead results over time
That is down 1.22 ppb from 3.9 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Arlington Water Dept. (Mwra) is 17.4 ppb across 11 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 2.68 ppb |
| 2024 | 3.9 ppb |
| 2024 | 17.4 ppb over 15 |
| 2024 | 2.17 ppb |
| 2023 | 3.7 ppb |
| 2021 | 8.3 ppb |
| 2019 | 6.04 ppb |
| 2018 | 2.79 ppb |
| 2017 | 4.59 ppb |
| 2017 | 1.39 ppb |
| 2016 | 6.3 ppb |
Against other Massachusetts systems
Of the 535 Massachusetts systems with a lead result, the median latest reading is 1.7 ppb; 13 are over 15 ppb right now and 66 have gone over at some point. Arlington Water Dept. (Mwra)'s 2.68 ppb sits at the 66th percentile in Massachusetts and the 79th nationally (higher means more lead).
Other water systems in Middlesex County
94 other systems share Middlesex County; 31 of them have a higher latest lead result than Arlington Water Dept. (Mwra). If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Lowell Regional Water Utility | 120,418 | 0 (not detected) |
| Cambridge Water Department | 118,214 | 8 ppb |
| Newton Water Dept. (Mwra) | 88,931 | 1.09 ppb |
| Somerville Water Dept. (Mwra) | 81,045 | 6.62 ppb |
| Framingham Water Dept. (Mwra) | 72,362 | 1.74 ppb |
| Malden Water Division (Mwra) | 66,263 | 9.74 ppb |
| Waltham Water Department | 65,218 | 2.24 ppb |
| Medford Water Dept. (Mwra) | 61,700 | 8.31 ppb |
| Everett Water Dept. (Mwra) | 49,075 | 1.25 ppb |
| Billerica Water Works | 42,119 | 2.4 ppb |
Next steps for Arlington, MA
Test your own tap with a certified lab first-draw sample; Arlington, MA may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Arlington Water Dept. (Mwra) whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. The lead result guide covers how utilities pick the homes they sample. Why an old exceedance still matters: over the limit before, under it now.