Castaic, CA Water Safety: 81/100 (2026)
2 ZIP codes · 2 water systems · Updated 2026-06-03
Drinking water tracked for Castaic 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 Castaic Compares
Data: EPA SDWIS Last verified: 2026-06-03
Castaic Water: The Quick Version
- Average lead level: 0.0007 mg/L.
- Estimated remediation: $1,300 per household.
- CDC health risk index: 10.71.
Water Systems Serving Castaic
Castaic, CA draws its residential water from 2 separate providers among the 2 federally tracked systems. Each operates independently, with its own infrastructure, rate structure, and compliance record.
Overview
We track water quality and home safety data for 2 ZIP codes in Castaic, California (population ~27,278), covering 2 community water systems serving approximately 301,090 people region-wide.
No EPA violations recorded across any ZIP codes in Castaic — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Castaic: B (81/100)
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
Castaic water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0007 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): 2 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 91310 | B | Peter Pitchess Honor Rancho Detn. Ctr | 7,000 |
| 91384 | B | Peter Pitchess Honor Rancho Detn. Ctr | 7,000 |
All ZIP Codes in Castaic
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 Castaic
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
Castaic: Remediation Cost in Perspective
When remediation costs are measured against Castaic home values, the resulting ratio is in the low tier — addressing documented water and safety issues here claims only a minor fraction of typical equity, and most homeowners are in a position where the financial commitment is straightforward rather than a material burden on their household budget.
Remediation costs in Castaic are relatively low compared to home values. The $600–$2,100 estimated range is a small fraction of median property value. Home values are 6% below the California average.
Protecting Children from Lead in Castaic
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.
Lead risk in Castaic appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Castaic
NFIP records stretching across multiple decades show Castaic accumulating 14 claims and carrying 50% of its ZIP codes inside FEMA flood zones — evidence of meaningful exposure that extends beyond isolated incidents. The mechanisms linking flooding to water quality haven't changed: treatment facilities can be overwhelmed, wells can be infiltrated, and distribution systems can experience backflow. For a community at this exposure level, those mechanisms shift from hypothetical to periodically relevant.
Castaic has a moderate flood history with 14 FEMA claims averaging $2,059 per payout. 50% 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>$1,300</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 Castaic, CA