Drinking water quality, RI
Rhode Island contaminants ranked by SDWA exceedance
Which regulated contaminants exceed their maximum contaminant level (MCL) most often across Rhode Island's community water systems, per EPA's Six-Year Review sample-level dataset (2012-2019). Source data is public; every value is citable.
Top 15 contaminants by exceedance count
| Contaminant | Category | Samples | Above MCL | Munis affected |
|---|---|---|---|---|
| 1,1,2-trichloroethane | - | 1,197 | 0 | 61 |
| 1,1-dichloroethylene | - | 1,197 | 0 | 61 |
| 1,2,4-trichlorobenzene | - | 1,197 | 0 | 61 |
| 1,2-dibromo-3-chloropropane | - | 389 | 0 | 51 |
| 1,2-dichloroethane | - | 1,197 | 0 | 61 |
| 1,2-dichloropropane | - | 1,197 | 0 | 61 |
| 2,4,5-tp | - | 495 | 0 | 57 |
| 2,4-d | - | 499 | 0 | 57 |
| alachlor | - | 788 | 0 | 60 |
| antimony, total | inorganic | 549 | 0 | 61 |
| arsenic | inorganic | 553 | 0 | 61 |
| asbestos | - | 6 | 0 | 5 |
| atrazine | - | 789 | 0 | 60 |
| barium | inorganic | 551 | 0 | 61 |
| 1,1,1-trichloroethane | - | 1,197 | 0 | 61 |
For citizens
Look up your own water system by name on the muni search, then read the drinking-water quality band on its profile page for per-contaminant readings + MCL ratios.
For chemical suppliers
Contaminants near or above MCL signal treatment-chemical procurement pressure. Lane intelligence pairs this with per-chemical bid timing on the supplier tier.