San Ysidro, CA Water Safety: 66/100 (2026)
2 ZIP codes · 3 water systems · Updated 2026-07-19
ZipCheckup grade for San Ysidro: C.
A mixed picture - some signals here are worth your attention.
Safe water is the norm across most of San Ysidro, CA - but documented violations push the city to the middle safety tier.
How San Ysidro Compares
Data: EPA SDWIS Last verified: 2026-07-19
San Ysidro's Water Providers
Residential addresses in San Ysidro, CA are served by 3 primary water providers out of 3 systems in federal records. Each system maintains separate infrastructure and files its own EPA compliance reports, so service conditions are not uniform across the city.
- C
- C
- C
Overview
We track water quality and home safety data for 2 ZIP codes in San Ysidro, California (population ~26,507), covering 3 community water systems serving approximately 1,491,617 people region-wide.
No EPA violations are recorded for the tracked water systems in San Ysidro as of the latest reporting period.
Home Safety Score
Average Home Safety Score for San Ysidro: C (66/100)
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
San Ysidro water systems draw from: Groundwater, Surface water.
Lead & Copper
- Lead data: not yet available for San Ysidro
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 2 ZIP codes
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 92143 | C | LOS TULES MUTUAL WATER COMPANY | 238 |
| 92173 | C | SAN DIEGO, CITY OF | 1,385,379 |
All ZIP Codes in San Ysidro
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.
San Ysidro 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
What You Can Do in San Ysidro
- 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 San Ysidro, CA