Lathrop, CA Water Safety: 90/100 (2026)
1 ZIP code · 6 water systems · Updated 2026-06-03
Looking at federal monitoring data for Lathrop, CA: the city clears benchmarks set under the Safe Drinking Water Act with room to spare — recorded exceedances are rare, and the systems serving local households have not triggered any pattern of repeat deficiencies in recent cycles.
How Lathrop Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Lathrop Water
- Average lead level: 0.0007 mg/L.
- Homes built before 1986: 20% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 11.38.
Who Supplies Your Water in Lathrop
3 water utilities share the residential service territory in Lathrop, CA — out of 6 total systems in federal records.
Overview
We track water quality and home safety data for 1 ZIP code in Lathrop, California (population ~33,015), covering 6 community water systems serving approximately 220,544 people region-wide.
No EPA violations recorded across any ZIP codes in Lathrop — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Lathrop: A (90/100)
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
Lathrop water systems draw from: Groundwater, Surface water.
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 3 (Low Risk)
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 95330 | A | City of Lathrop | 35,080 |
All ZIP Codes in Lathrop
- 95330 [A]
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 Lathrop
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
Housing & Infrastructure in Lathrop
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
Since 1986, federal law has prohibited lead solder in new residential plumbing. With a median build year of 2006, much of Lathrop's housing falls on the safer side of that line — though homes built before 1986 still warrant testing regardless of the city-wide profile.
Most homes in Lathrop 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 Lathrop Homeowners
Property equity in Lathrop runs well ahead of estimated remediation costs — a cost-to-value ratio that sits in the low tier, meaning documented water and safety issues here are the kind homeowners can plan to address without treating the expense as a significant budget event relative to what their homes are worth.
Remediation costs in Lathrop are relatively low compared to home values. The $1,600–$3,300 estimated range is a small fraction of median property value. Home values are 18% below the California average.
Lead Exposure Risk for Children in Lathrop
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.
Aggregate sampling rests beneath the federal action threshold here, while only 20% of Lathrop housing predates the solder rule change.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Lathrop
Flood history in Lathrop spans 29 NFIP claims and 100% flood zone coverage — enough to place it in moderate-exposure territory where flood events are genuinely recurring rather than statistical outliers. That distinction matters for water quality assessment because the connection between flooding and water safety is not uniform across communities. In low-exposure areas, flooding rarely generates the conditions needed to compromise treatment or distribution infrastructure. In high-exposure areas, it can do so repeatedly. Moderate-exposure communities sit in between: flood events occur with enough frequency to make periodic infrastructure stress a reasonable concern, particularly for private well owners and residents in lower-elevation FEMA-designated zones.
Lathrop has a moderate flood history with 29 FEMA claims averaging $26,088 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>$2,400</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.
Deep Dive Reports
Detailed analysis for Lathrop, CA