Holum Water System, LA
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2024-2026). 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.
Who runs the water here
Holum Water System serves about 1,230 people through 410 service connections, which makes it a small system under EPA's size classes. It is privately owned and draws groundwater, in Caldwell Parish County, Louisiana. EPA system ID: LA1021007; phone on file: 318-649-5575. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
Against the period ending 2023 (1 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Holum Water System is 3 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 1 ppb |
| 2023 | 1 ppb |
| 2020 | 3 ppb |
| 2017 | 1 ppb |
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. Holum Water System's 1 ppb sits at the 59th percentile in Louisiana and the 54th nationally (higher means more lead).
Neighbouring systems
10 other systems share Caldwell Parish County; 2 of them have a higher latest lead result than Holum Water System. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Hebert Water System | 3,048 | 0 (not detected) |
| East Columbia Water System | 2,829 | 0 (not detected) |
| Columbia Heights Water District | 1,965 | 2.8 ppb |
| Village Of Grayson Water System | 1,461 | 0.81 ppb |
| Kelly Water District | 1,314 | 0.86 ppb |
| Wards 4 & 5 Water System | 1,002 | 5 ppb |
| Village Of Columbia Water System | 945 | 0 (not detected) |
| Town Of Clarks Water System | 906 | 0 (not detected) |
| Cotton Plant Water System | 783 | 0 (not detected) |
| Vixen Water System | 750 | 0 (not detected) |
Your move
Test your own tap with a certified lab first-draw sample; Grayson, 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 Holum 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.