Plaisance Water System, LA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (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 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Who runs the water here
Plaisance Water System serves about 6,465 people through 2,155 service connections, which makes it a medium-sized system under EPA's size classes. It is privately owned and draws groundwater, in St. Landry Parish County, Louisiana. EPA system ID: LA1097012; phone on file: 337-501-2599. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2022 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Plaisance Water System is 2 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 0 (not detected) |
| 2022 | 0 (not detected) |
| 2019 | 2 ppb |
| 2016 | 1 ppb |
Against other Louisiana systems
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. Plaisance Water System's reported as 0 (not detected) sits at the 39th percentile in Louisiana and the 36th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Neighbouring systems
26 other systems share St. Landry Parish County; 13 of them have a higher latest lead result than Plaisance 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 |
| 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 |
| Lawtell Water Works District No 1 | 3,717 | 0 (not detected) |
Next steps for Opelousas, LA
Look up your address in Plaisance Water System's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Plaisance 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. Small systems behave differently: why small systems go over more often.