Colusa, CA: 1 Health Violation — 77/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
Drinking water tracked for Colusa by CA authorities posts above-average scores — the majority of systems are free from health-based exceedances and the city's grade sits above the state median.
How Colusa Compares
Data: EPA SDWIS Last verified: 2026-06-03
Colusa Water: The Quick Version
- Your city's water systems recorded 4 violations in the past 5 years.
- Average lead level: 0.0068 mg/L.
- Homes built before 1986: 66% — older plumbing may contain lead solder.
- Estimated remediation: $1,500 per household.
- CDC health risk index: 12.53 — above typical levels.
Water Systems Serving Colusa
With 2 utilities splitting service in Colusa, CA, water accountability is distributed across 2 systems on the federal record.
Overview
We track water quality and home safety data for 1 ZIP code in Colusa, California, covering 2 community water systems serving approximately 7,672 people.
1 of 1 ZIP code (100%) have recorded EPA violations. 1 health-based violation documented.
Home Safety Score
Average Home Safety Score for Colusa: B (77/100)
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
Colusa water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0068 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 2 DBP Rule | Treatment Technique | 4 | 1 |
| Consumer Confidence Report Rule | Reporting | 4 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 95932 | B | 4 | 1 | City of Colusa |
All ZIP Codes in Colusa
- 95932 [B] — 4 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.
CDC Health Data for Colusa
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
Key Contaminants Detected in Colusa
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is Colusa's Housing Stock?
With 66% 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
The median home in Colusa was built in 1975 — a figure that places most of the city's residential stock in the era when lead solder was still standard in copper plumbing. Homes built before 1986 may have lead-soldered joints; those built before 1970 face the additional possibility of lead pipes in the service line itself.
Over half of homes in Colusa 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.
Colusa: Remediation Cost in Perspective
In Colusa, property wealth outpaces what documented remediation typically demands — the equity burden lands well within the low tier.
Remediation costs in Colusa are relatively low compared to home values. The $950–$2,400 estimated range is a small fraction of median property value. Home values are 50% below the California average.
Protecting Children from Lead in Colusa
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.
Despite citywide averages serving as the standard public reference point, those aggregates cannot resolve what is happening at one specific faucet — and where 66% of Colusa homes come from before the solder rule or where utility samples sit at or above the action mark, the gap between system data and faucet reality matters more than it does in lower-exposure communities. An in-home draw closes that gap, with certified filtration through retailer networks available where confirmed faucet results warrant additional measures.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Colusa
100% of ZIP codes in Colusa are mapped into FEMA-designated flood zones, and the NFIP records 107 claims reflecting a multi-event flood history. That combination places local flood exposure in the range where water-quality implications deserve at least periodic attention.
Colusa has a moderate flood history with 107 FEMA claims averaging $19,303 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>$1,500</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 Colusa, CA