Lewiston, ID: 1 Health Violation — 94/100 (2026)
1 ZIP code · 5 water systems · Updated 2026-06-03
In current ID EPA data, Lewiston's tap water sits in the high-safety tier.
How Lewiston Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Lewiston Water
- Your city's water systems recorded 9 violations in the past 5 years.
- Average lead level: 0.001 mg/L.
- Homes built before 1986: 72% — older plumbing may contain lead solder.
- Estimated remediation: $2,000 per household.
- CDC health risk index: 13.5 — above typical levels.
Who Supplies Your Water in Lewiston
3 water utilities share the residential service territory in Lewiston, ID — out of 5 total systems in federal records.
Overview
We track water quality and home safety data for 1 ZIP code in Lewiston, Idaho, covering 5 community water systems serving approximately 37,478 people.
1 of 1 ZIP code (100%) have recorded EPA violations. 1 health-based violation documented.
Home Safety Score
Average Home Safety Score for Lewiston: A (94/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Lewiston water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0010 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 8 | 1 |
| Lead | Inorganic | 4 | 1 |
| Stage 2 DBP Rule | Treatment Technique | 4 | 1 |
| Lead and Copper Rule | Treatment Technique | 2 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 83501 | A | 9 | 1 | Lewiston Orchards Irrigation District |
All ZIP Codes in Lewiston
- 83501 [A] — 9 violations ⚠
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Health Outcomes in Lewiston
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Top Contaminants in Lewiston Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Housing & Infrastructure in Lewiston
With 72% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Two dates define the high-risk tiers of residential plumbing from a lead standpoint: 1970, before which lead pipes were commonly installed for service connections, and 1986, before which lead solder was standard in copper plumbing. A median build year of 1978 places Lewiston's housing distribution well within that older risk zone. The bar chart above breaks down how much of the stock falls into each era — and the pre-1986 share alone represents more than half the residential inventory, making plumbing-era risk a defining characteristic of the local water safety picture.
Over half of homes in Lewiston were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Lewiston Homeowners
Property equity in Lewiston runs well ahead of estimated remediation costs — a cost-to-value ratio that sits in the low tier, meaning documented water and safety issues here are the kind homeowners can plan to address without treating the expense as a significant budget event relative to what their homes are worth.
Remediation costs in Lewiston are relatively low compared to home values. The $1,250–$3,200 estimated range is a small fraction of median property value. Home values are 11% below the Idaho average.
Lead Exposure Risk for Children in Lewiston
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Locally, 72% of Lewiston homes carry interior plumbing from the era when lead solder was still permitted in new builds, and citywide monitoring approaches or crosses the EPA action benchmark. Households can find a draw-test kit and certified filtration through verified retailers.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Lewiston
Although Lewiston's flood history doesn't reach high-severity thresholds, NFIP data documents 5 claims and FEMA maps place 100% of ZIP codes in designated flood zones — a combined profile that makes flood-related water quality considerations a reasonable planning baseline.
Lewiston has a moderate flood history with 5 FEMA claims averaging $1,355 per payout. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$2,000</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
Deep Dive Reports
Detailed analysis for Lewiston, ID