COE MCNARY DAM
PWS ID: OR4190178 · WALLA WALLA, Oregon 99362
Population Served
120
Total Violations
463
Health-Based Violations
3
Water Source
Groundwater
System Details
- System Type
- Non-Transient Non-Community
- Owner Type
- Federal
- Connections
- 6
- County
- Umatilla
- School/Daycare
- No
- MCL Violations
- 3
- Monitoring Violations
- 454
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 11 | 2006 |
| Nitrate | MR | 11 | 2006 |
| Carbon tetrachloride | MR | 8 | 2005 |
| cis-1,2-Dichloroethylene | MR | 8 | 2005 |
| Ethylbenzene | MR | 8 | 2005 |
| p-Dichlorobenzene | MR | 8 | 2005 |
| Styrene | MR | 8 | 2005 |
| Toluene | MR | 8 | 2005 |
| Xylenes, Total | MR | 8 | 2005 |
| Trichloroethylene | MR | 8 | 2005 |
| Vinyl chloride | MR | 8 | 2005 |
| o-Dichlorobenzene | MR | 8 | 2005 |
| trans-1,2-Dichloroethylene | MR | 8 | 2005 |
| 1,2-Dichloroethane | MR | 8 | 2005 |
| 1,1,1-Trichloroethane | MR | 8 | 2005 |
| 1,2-Dichloropropane | MR | 8 | 2005 |
| 1,1,2-Trichloroethane | MR | 8 | 2005 |
| Benzene | MR | 8 | 2005 |
| Benzo(a)pyrene | MR | 8 | 2014 |
| 1,1-Dichloroethylene | MR | 8 | 2005 |
| Tetrachloroethylene | MR | 8 | 2005 |
| DICHLOROMETHANE | MR | 8 | 2005 |
| CHLOROBENZENE | MR | 8 | 2005 |
| 1,2,4-Trichlorobenzene | MR | 8 | 2005 |
| 2,4-D | MR | 7 | 2005 |
| 2,4,5-TP | MR | 7 | 2005 |
| BHC-GAMMA | MR | 7 | 2005 |
| Carbofuran | MR | 7 | 2005 |
| Dinoseb | MR | 7 | 2005 |
| Diquat | MR | 7 | 2005 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.