Winchester, CA Water Safety: 63/100 (2026)
1 ZIP code · 3 water systems · Updated 2026-06-03
Although much of Winchester meets baseline drinking water standards, some CA-tracked service areas show violations that merit a closer look — particularly for older housing stock.
How Winchester Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Winchester Residents
- Homes built before 1986: 7% — older plumbing may contain lead solder.
- Estimated remediation: $2,100 per household.
- CDC health risk index: 12.09 — above typical levels.
Winchester's Water Providers
Federal drinking water records identify 3 systems in Winchester, CA. The leading 3 providers serve the largest share of residential connections, each operating as a separate entity with its own rate authority, infrastructure management, and EPA compliance obligations — so service conditions are not uniform city-wide.
Overview
We track water quality and home safety data for 1 ZIP code in Winchester, California (population ~36,725), covering 3 community water systems serving approximately 812,798 people region-wide.
No EPA violations recorded across any ZIP codes in Winchester — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Winchester: C (63/100)
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
Winchester water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for Winchester
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 92596 | C | Eastern Municipal Water District | 666,581 |
All ZIP Codes in Winchester
- 92596 [C]
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.
Winchester Community Health Snapshot
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
Winchester Infrastructure Age
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
Winchester's housing stock skews relatively recent, with a median build year of 2003. Homes constructed after 1986 avoid the lead-soldered copper joints that were standard before the federal ban — reducing aggregate risk from plumbing as a contamination pathway.
Most homes in Winchester 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.
How Remediation Costs Compare in Winchester
Low proportionality — that's the Winchester picture when remediation costs are placed against typical home equity.
Remediation costs in Winchester are relatively low compared to home values. The $1,100–$3,400 estimated range is a small fraction of median property value. Home values are 17% below the California average.
Winchester: Lead Risk & Vulnerable Populations
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.
Pre-rule stock in Winchester accounts for 7% of the inventory — a modest fraction — and citywide samples land safely beneath the federal action mark.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Winchester: Flood History & Water Damage Risk
FEMA data shows 100% of Winchester's ZIP codes mapped into designated flood zones, paired with an NFIP record of 1 claim. That footprint places local flood exposure in the range where it warrants attention without rising to high-severity planning territory.
Winchester has a moderate flood history with 1 FEMA claims averaging $1,947 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>$2,100</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 Winchester
- 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. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Winchester, CA