Loch Alpine Sanitary Authority, MI
Exceeded the action level in the past
Latest 90th-percentile lead: 7.2 ppb (monitoring period 2025-2025). 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 Loch Alpine Sanitary Authority
Loch Alpine Sanitary Authority serves about 1,506 people through 538 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Washtenaw County, Michigan. EPA system ID: MI0003940. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
That is down 81.8 ppb from 89 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Loch Alpine Sanitary Authority is 89 ppb across 4 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 7.2 ppb |
| 2023 | 89 ppb over 15 |
| 2020 | 3 ppb |
| 2017 | 6 ppb |
Against other Michigan systems
Of the 1,227 Michigan systems with a lead result, the median latest reading is 1 ppb; 31 are over 15 ppb right now and 109 have gone over at some point. Loch Alpine Sanitary Authority's 7.2 ppb sits at the 93rd percentile in Michigan and the 95th nationally (higher means more lead).
Other water systems in Washtenaw County
30 other systems share Washtenaw County; 0 of them have a higher latest lead result than Loch Alpine Sanitary Authority. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Ann Arbor | 123,851 | 2.3 ppb |
| Ypsilanti Community Utility Authority | 53,988 | 4.1 ppb |
| Pittsfield Township | 24,500 | 0 (not detected) |
| Saline | 9,158 | 0 (not detected) |
| Scio Township | 8,500 | 0 (not detected) |
| Milan | 7,363 | 5.1 ppb |
| Superior Township | 6,830 | 0 (not detected) |
| Chelsea | 5,474 | 0 (not detected) |
| Dexter | 4,500 | 0 (not detected) |
| Augusta Township | 3,907 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Ann Arbor, MI 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 Loch Alpine Sanitary Authority 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.