Grand Isle Water System, ME
Lead detected, under the action levels
Latest 90th-percentile lead: 2.1 ppb (monitoring period 2022-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Who runs the water here
Grand Isle Water System serves about 278 people through 111 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Aroostook County, Maine. EPA system ID: ME0092285; phone on file: 207-895-3420. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Grand Isle Water System's lead record
Against the period ending 2021 (2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Grand Isle Water System is 2.1 ppb across 5 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 2.1 ppb |
| 2021 | 2 ppb |
| 2018 | 1 ppb |
| 2018 | 1 ppb |
| 2016 | 1 ppb |
How Grand Isle Water System compares
Of the 358 Maine systems with a lead result, the median latest reading is 1.5 ppb; 2 are over 15 ppb right now and 40 have gone over at some point. Grand Isle Water System's 2.1 ppb sits at the 64th percentile in Maine and the 74th nationally (higher means more lead).
Nearby utilities
37 other systems share Aroostook County; 16 of them have a higher latest lead result than Grand Isle Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Presque Isle Utilities District | 6,128 | 1.5 ppb |
| Houlton Water Company | 4,735 | 3.4 ppb |
| Caribou Utilities District | 3,943 | 0 (not detected) |
| Madawaska Water District | 2,738 | 0 (not detected) |
| Van Buren Water District | 2,190 | 2.7 ppb |
| Fort Fairfield Utilities District | 2,025 | 1.8 ppb |
| Fort Kent W & W Department | 1,578 | 1.9 ppb |
| Mars Hill And Blaine Water Company | 1,500 | 3.4 ppb |
| Limestone Water & Sewer District | 875 | 2.6 ppb |
| Ashland Water & Sewer District | 713 | 2.3 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Grand Isle, ME 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 Grand Isle Water System 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. What a 90th-percentile result does and does not tell you: how to read a lead result. Size matters more than most people expect: small vs large water systems.