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

Home hazard report for 77521 — Baytown, TX

ZIP 77521 is served by Lake MUD: no health-based violations since 2016, latest lead result 2.7 ppb, PFAS 4 detected. Harris County is in EPA radon zone 3.

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Where ZIP 77521 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: Lake MUD

EPA IDTX1011741
People served6,048
Sourcesurface water (rivers, lakes)
Connections2,016

Health-based violations

No health-based violations reported since 2016.

Full record for Lake MUD →

Other systems overlapping this ZIP: Harris County MUD 213-A, Lazy Acres Mobile Home Park, City of Baytown.

Lead

Jan 20242.7 ppb
Jan 20210 ppb
Jan 20180 ppb
Jan 20151.4 ppb
Jan 20142 ppb
Jan 20114.1 ppb
Jan 20020.7 ppb
Jan 20000.7 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
PFBA7.3 ppt4 of 4—
PFPeA5 ppt2 of 4—
PFHxA4.8 ppt3 of 4—
PFBS3.3 ppt2 of 4—
HFPO-DA (GenX)not detected0 of 4—
PFDAnot detected0 of 4—
PFOAnot detected0 of 44 ppt MCL
PFHpAnot detected0 of 4—
PFHxSnot detected0 of 4—
PFNAnot detected0 of 4—
PFOSnot detected0 of 44 ppt MCL

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 Harris County

EPA radon zone 3 — low potential. Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.

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 very low social vulnerability and very high community resilience.

LightningVery High
TornadoVery High
Cold waveRelatively High
Heat waveRelatively High
HurricaneRelatively High
Ice stormRelatively High
Riverine floodingRelatively High
Strong windRelatively High
HailRelatively Moderate
WildfireRelatively Moderate
Winter weatherRelatively Moderate
Coastal floodingRelatively Low
DroughtRelatively Low
EarthquakeVery Low
LandslideVery 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
San Jacinto River Waste Pits
Channelview, Texas · EPA ID TXN000606611
Active (final NPL)6.1 mi
Highlands Acid Pit
Highlands, Texas · EPA ID TXD980514996
Active (final NPL)6.9 mi
French, Ltd.
Crosby, Texas · EPA ID TXD980514814
Active (final NPL)8.1 mi
Sikes Disposal Pits
Crosby, Texas · EPA ID TXD980513956
Active (final NPL)8.8 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.

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 77521

Who supplies drinking water to ZIP 77521?

Lake MUD (EPA ID TX1011741), a surface water (rivers, lakes) system serving about 6,048 people.

Is there lead in Baytown, TX tap water?

The utility’s latest 90th-percentile lead result (Jan 2024) was 2.7 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 Baytown, TX water have PFAS?

PFAS were detected, with PFOA and PFOS below 4.0 ppt (highest not detected).

Has the water system in 77521 had violations?

No health-based violations reported since 2016.

What natural hazards affect ZIP 77521?

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

Are there Superfund sites near 77521?

The nearest active Superfund site is 6.1 miles away. Sites within 10 miles: San Jacinto River Waste Pits (6.1 mi, Active (final NPL)); Highlands Acid Pit (6.9 mi, Active (final NPL)); French, Ltd. (8.1 mi, Active (final NPL)).

Is radon a problem in Harris County?

Harris County is in EPA radon zone 3 (low potential). Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.