Town Of Grand Coteau Water System, LA
Lead detected, under the action levels
Latest 90th-percentile lead: 5 ppb (monitoring period 2026-2026). 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.
About Town Of Grand Coteau Water System
Town Of Grand Coteau Water System serves about 1,650 people through 550 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 St. Landry Parish County, Louisiana. EPA system ID: LA1097001; phone on file: 337-662-5246. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Every lead result on file
That is down 2 ppb from 7 ppb in the period ending 2025. The highest 90th-percentile result EPA holds for Town Of Grand Coteau Water System is 7 ppb across 7 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 5 ppb |
| 2025 | 7 ppb |
| 2024 | 1 ppb |
| 2024 | 1 ppb |
| 2023 | 3 ppb |
| 2020 | 1 ppb |
| 2019 | 4 ppb |
How Town Of Grand Coteau Water System compares
Of the 802 Louisiana systems with a lead result, the median latest reading is 0.72 ppb; 4 are over 15 ppb right now and 30 have gone over at some point. Town Of Grand Coteau Water System's 5 ppb sits at the 95th percentile in Louisiana and the 91st nationally (higher means more lead).
Other water systems in St. Landry Parish County
26 other systems share St. Landry Parish County; 0 of them have a higher latest lead result than Town Of Grand Coteau Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| City Of Opelousas Water System | 20,388 | 1 ppb |
| Lawco - Eunice Water System | 15,471 | 2 ppb |
| Town Of Leonville Water System | 9,552 | 2.5 ppb |
| Lewisburg Bellevue Water System | 8,325 | 0 (not detected) |
| Savoy Swords Water System Inc | 7,326 | 2 ppb |
| Plaisance Water System | 6,465 | 0 (not detected) |
| Prairie Ronde Water System Inc | 6,105 | 0 (not detected) |
| St Landry Water Works District 2 Rural | 4,761 | 0.92 ppb |
| Town Of Sunset Water System | 4,356 | 0.39 ppb |
| Town Of Port Barre Water System | 3,828 | 0.75 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Grand Coteau, LA 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 Town Of Grand Coteau Water System whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 2000 ppb (copper action level 1,300 ppb).
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. Systems that went over once often dip back under; here is what that means.