Caldwell, ID: 24 Violations — 64/100 (2026)
3 ZIP codes · 8 water systems · Updated 2026-06-03
Public water data for Caldwell, ID reveals a split picture — tap water quality varies meaningfully by service area and the city's grade reflects that variability.
How Caldwell Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Caldwell Water
- Your city's water systems recorded 24 violations in the past 5 years.
- Average lead level: 0.008 mg/L.
- Homes built before 1986: 39% — older plumbing may contain lead solder.
- Estimated remediation: $1,400 per household.
- CDC health risk index: 12.08 — above typical levels.
Who Supplies Your Water in Caldwell
Structurally, Caldwell, ID's water supply is divided. Federal data identifies 8 water systems in the area, with 3 providers serving the bulk of residential connections. These utilities operate independently, meaning rate-setting authority and EPA compliance accountability are distributed rather than centralized.
Overview
We track water quality and home safety data for 3 ZIP codes in Caldwell, Idaho (population ~74,959), covering 8 community water systems serving approximately 190,094 people region-wide.
3 of 3 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Caldwell: C (64/100)
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
Caldwell water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0080 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 3 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 20 | 3 |
| Barium | Inorganic | 8 | 3 |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 4 | 3 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 83605 | C | 8 | 0 | City of Caldwell |
| 83606 | C | 8 | 0 | City of Caldwell |
| 83607 | C | 8 | 0 | City of Caldwell |
All ZIP Codes in Caldwell
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 Caldwell
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 Caldwell Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Housing & Infrastructure in Caldwell
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
The story of Caldwell's housing stock is one of layered development — neighborhoods built in different decades, each carrying the plumbing standards of their era. The median build year of 1996 reflects that layered character. Before 1986, lead solder was standard in copper plumbing; before 1970, lead pipes were commonly used for service lines. A substantial portion of the pre-1986 homes visible in the distribution above still carry the plumbing materials of those earlier standards — creating a risk environment that the city-wide aggregate water data doesn't fully capture.
Most homes in Caldwell were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Caldwell Homeowners
The household financial picture for Caldwell homeowners is proportionally favorable — addressing documented issues claims a small slice of equity, and the cost-to-value ratio puts this area well within the manageable tier.
Remediation costs in Caldwell are relatively low compared to home values. The $667–$2,233 estimated range is a small fraction of median property value. Home values are 16% above the Idaho average.
Lead Exposure Risk for Children in Caldwell
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.
Routinely in Caldwell, where 39% of housing predates the solder ban and aggregate utility readings hover near the federal threshold, a faucet-level draw functions as a standard household step for families with small kids.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Caldwell
Flood risk in Caldwell occupies the middle ground: 3 NFIP claims and 67% of local ZIP codes within FEMA flood zones. At that level, the risk pathways connecting flooding to water quality — treatment system stress, well infiltration, distribution backflow — become relevant considerations during significant flood events, even if day-to-day water quality is unaffected by flood history.
Caldwell has a moderate flood history with 3 FEMA claims averaging $8,674 per payout. 67% 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>$1,400</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.
What You Can Do in Caldwell
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Stage 1 DBP Rule can reduce the most common contaminant found in Caldwell's water.
- Check your home's plumbing. With 39% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Caldwell, ID