EPA data as of Oct 2026 · page updated 2026-10-29

Home hazard report for 93257 — Porterville, CA

ZIP 93257 is served by City of Porterville: 1 violation since 2016, latest lead result 0 ppb, PFAS 23 ppt. Tulare County is in EPA radon zone 2.

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Where ZIP 93257 is

Dashed: ZIP area · blue: utility service area · scroll or pinch to zoom
ZIP code areaZIP center Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

Drinking water: City of Porterville

EPA IDCA5410010
People served63,487
Sourcegroundwater (wells)
Connections17,750

Health-based violations

Contaminant or ruleHealth-based violations since 2016
Lead and Copper Rule Revisions1

A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. 1 still listed as unresolved (“unaddressed” or “addressed” but not yet returned to compliance); the latest began Oct 2024.

Full record for City of Porterville →

Lead

Jan 20230 ppb
Jan 20203 ppb
Jan 20178 ppb
Jan 20140 ppb
Jan 20110 ppb
Jan 20080 ppb
Jan 20065 ppb
Jan 20055 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS (“forever chemicals”)

CompoundHighest resultSamples with detectionEPA limit
PFOS23 ppt13 of 584 ppt MCL
PFOA22 ppt2 of 584 ppt MCL
PFPeA9.3 ppt2 of 58—
PFBS9.1 ppt5 of 58—
PFHxA8.5 ppt2 of 58—
PFHpA6.5 ppt2 of 58—
PFBA5.8 ppt2 of 58—
PFHxS3.6 ppt4 of 58—
HFPO-DA (GenX)not detected0 of 58—
PFDAnot detected0 of 58—
PFNAnot detected0 of 58—

EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), samples 2023–2025; ppt = parts per trillion (ng/L). The 4.0 ppt maximum contaminant levels for PFOA and PFOS were set by EPA in 2024; water systems have until the end of the decade to comply.

Radon in Tulare County

EPA radon zone 2 — moderate potential. Predicted average indoor radon between 2 and 4 pCi/L. Test your home; many homes here exceed 4 pCi/L.

Radon is a colorless, odorless radioactive gas from soil and rock, and the leading cause of lung cancer among non-smokers. EPA recommends fixing a home at 4 pCi/L or above and considering it from 2 pCi/L. A short-term test kit costs about $15–30. How radon zones work →

Natural hazard risk

FEMA rates the overall natural-hazard risk of this neighborhood (census tract) as Relatively High, with relatively high social vulnerability and very low community resilience.

Riverine floodingVery High
Heat waveRelatively High
WildfireRelatively High
EarthquakeRelatively Moderate
LightningRelatively Moderate
DroughtRelatively Low
HailRelatively Low
LandslideRelatively Low
Winter weatherRelatively Low
Strong windVery Low
TornadoVery Low
Volcanic activityVery Low

FEMA National Risk Index (December 2025): expected annual losses from each hazard combined with social vulnerability and community resilience, rated relative to all U.S. census tracts. Hazards not listed are not applicable here. It describes the area, not a single building; flood insurance maps (FEMA FIRMs) decide flood-insurance requirements.

Live conditions: river gauges and flood levels · tornado warnings · wildfire detections · earthquakes — our sister maps, updated from NOAA, USGS and NASA every few minutes.

Superfund sites nearby

SiteStatusDistance
Beckman Instruments (Porterville Plant)
Porterville, California · EPA ID CAD048645444
Cleaned up & deleted8.7 mi

EPA Superfund National Priorities List (NPL): the country’s most serious known hazardous-waste sites, each with an EPA cleanup record (linked). Distance is measured from the ZIP center to the site’s reference point; being near a site does not by itself mean exposure — EPA site pages describe what was found and how it is being cleaned up.

Buying a home in Porterville? See the 2026 conforming, FHA and jumbo loan limits for Tulare County →

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions about 93257

Who supplies drinking water to ZIP 93257?

City of Porterville (EPA ID CA5410010), a groundwater (wells) system serving about 63,487 people.

Is there lead in Porterville, CA tap water?

The utility’s latest 90th-percentile lead result (Jan 2023) was 0 ppb; EPA’s action level is 15 ppb, falling to 10 ppb from 2027. Lead mostly comes from service lines and home plumbing, so the only way to know your tap is to test it.

Does Porterville, CA water have PFAS?

Highest PFOA or PFOS result in EPA’s 2023–2025 testing was at or above 4.0 ppt, EPA’s 2024 maximum contaminant level for each. 8 PFAS compounds detected.

Has the water system in 93257 had violations?

Health-based violations since 2016: Lead and Copper Rule Revisions. 1 is still listed as unresolved in EPA records.

What natural hazards affect ZIP 93257?

FEMA’s National Risk Index rates the overall natural-hazard risk here as Relatively High; the highest-rated hazards are riverine flooding (very high), heat wave (relatively high), wildfire (relatively high).

Are there Superfund sites near 93257?

No active Superfund site within 10 miles of the ZIP center. Sites within 10 miles: Beckman Instruments (Porterville Plant) (8.7 mi, Cleaned up & deleted).

Is radon a problem in Tulare County?

Tulare County is in EPA radon zone 2 (moderate potential). Predicted average indoor radon between 2 and 4 pCi/L. Test your home; many homes here exceed 4 pCi/L.