St Marys Water System, LA
Exceeded the action level in the past
Latest 90th-percentile lead: 3 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. 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.
Who runs the water here
St Marys Water System serves about 294 people through 98 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Bossier Parish County, Louisiana. EPA system ID: LA1015023; phone on file: 318-326-5808. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
St Marys Water System's lead record
Against the period ending 2021 (4 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for St Marys Water System is 46 ppb across 4 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 3 ppb |
| 2021 | 4 ppb |
| 2021 | 46 ppb over 15 |
| 2018 | 14 ppb over 10 |
Where this result ranks
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. St Marys Water System's 3 ppb sits at the 87th percentile in Louisiana and the 82nd nationally (higher means more lead).
Other water systems in Bossier Parish County
18 other systems share Bossier Parish County; 0 of them have a higher latest lead result than St Marys 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 Bossier City Water System | 79,506 | 1 ppb |
| Village Water System | 24,813 | 0 (not detected) |
| Barksdale Afb Water System | 13,000 | 0 (not detected) |
| Town Of Benton Water System | 8,037 | 0 (not detected) |
| Cypress Black Bayou Water System | 5,520 | 1.2 ppb |
| Town Of Haughton Water System | 5,355 | 0 (not detected) |
| Sligo Water System Incorporated | 2,850 | 0 (not detected) |
| Town Of Plain Dealing Water System | 2,346 | 1 ppb |
| West Central Bossier Water System | 1,771 | 0 (not detected) |
| South Bossier Water System | 1,755 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Plain Dealing, 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 St Marys 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. More in what a past exceedance means today.