Water Quality: Lewiston, ID
9 water systems • 36,074 people served
Multiple Health ViolationsWater Quality Summary
Lewiston is served by 9 public water systems with a combined service population of 36,074 people, and has 384 EPA Safe Drinking Water Act violations on record. Critically, 45 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Lewiston's violation count is 189% above the national average for Idaho. Contaminants associated with violations include Chlorine Dioxide, E. coli, Gross Alpha, Selenium, Stage 2 DBP.
Contaminants Found
Can cause anemia in infants and young children; may cause nervous system effects at high levels.
Common source: Water treatment disinfectant used to control taste, odor, and microorganisms
EPA limit: 0.8 mg/L
Causes gastrointestinal illness; certain strains (e.g., O157:H7) can cause severe kidney failure and death.
Common source: Fecal contamination from humans or animals entering the water supply
EPA limit: Zero (no E. coli permitted in drinking water)
Alpha-emitting radioactive particles increase cancer risk, particularly from bone and other internal cancers.
Common source: Natural uranium and radium in geological formations
EPA limit: 15 pCi/L (excluding radon and uranium)
Hair loss, nail brittleness, and nervous system damage at elevated concentrations.
Common source: Natural geological deposits, mining discharges, oil refinery waste
EPA limit: 0.05 mg/L (50 ppb)
Trihalomethanes and haloacetic acids that increase cancer risk and may cause adverse reproductive outcomes.
Common source: Chlorine disinfection reacting with natural organic matter in source water
EPA limit: TTHM: 0.080 mg/L; HAA5: 0.060 mg/L
Water Systems Serving Lewiston
| System Name | PWSID | Source | Population | Violations |
|---|---|---|---|---|
| LEWISTON ORCHARDS IRRIGATION DIST | ID2350015 | Groundwater | 20,000 | 88 |
| LEWISTON CITY OF | ID2350014 | Surface Water | 15,001 | 0 |
| RED PHEASANT WATER COMPANY LLC | ID2350040 | Groundwater | 480 | 21 |
| COUGAR RIDGE WATER & SEWER | ID2350036 | Groundwater | 173 | 1 |
| EAGLES POINTE SUBDIVISION | ID2350038 | Groundwater | 110 | 60 |
| WAHA GLEN WATER DIST | ID2350030 | Groundwater | 100 | 12 |
| EATON MOBILE HOME COURT | ID2350008 | Groundwater | 94 | 44 |
| RED ROCK WATER LLC | ID2350025 | Groundwater | 60 | 153 |
| VIEW POINT SUBDIVISION | ID2350042 | Groundwater | 56 | 5 |
Concerned About Your Water?
A home water filter can remove common contaminants. NSF-certified filters are tested against EPA standards.
Consider a reverse osmosis system for comprehensive filtration or a carbon filter for basic improvement.
Other Cities in Idaho
Data Sources
Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). Data includes all recorded violations for active community water systems.