FRESNO, California Tap Water Quality

630,234 people served · 42 water systems

Failing

Satellite imagery via Esri World Imagery — approximate city center, not a facility address.

FRESNO, California is a large city with 630,234 residents served by 42 distinct public water systems. Water service covers ZIP codes 93701, 93703, 93704, 93706, 93710, 93711, and 9 more.

FRESNO has accumulated a significant number of EPA health-based violations. Reviewing the contaminants involved, requesting your utility's Consumer Confidence Report, and using certified point-of-use filtration is strongly advisable.

EPA reporting identifies Lead, Haloacetic Acids (HAA5), Total Trihalomethanes (TTHMs), Nitrate, and Uranium among the regulated contaminants associated with FRESNO's recent health-based violations. Each contaminant has different sources, health implications, and recommended mitigation steps — links to the full EPA reference for each are listed alongside the violation history below.

FRESNO's 75 violations is above the California average of 4.1 per city — worth reviewing the contaminant breakdown below.

Last updated: 2026-05-18 · Source: EPA SDWIS

Location

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Centered on ZIP-code centroids of water systems serving this city.

ZIP Codes Served

93701 93703 93704 93706 93710 93711 93721 93722 93725 93728 93729 93737 93740 93747 93790

Health-Based Violations (Last 5 Years)

EPA Maximum Contaminant Level exceedances reported by water systems serving FRESNO. Each entry explains the contaminant, the health risk, and recommended precautions, and links to a full guide.

Uraniumradiological

EPA Code 4006 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.03 mg/L

Last Reading

222.5 PCI/L

First Reported

Jan 2023

Most Recent

Oct 2025

What this violation means

Uranium in drinking water is both a chemical toxin (kidney damage) and a radiological hazard (increased cancer risk). It's most commonly found in groundwater near uranium ore deposits or former mining activity in the Western US.

Recommended precautions

→Reverse osmosis is the gold standard for removing uranium.
→Ion exchange systems work but must be sized correctly for uranium.
→If you live near former mining sites, test for uranium even if not required.

Read the complete guide to Uranium

Nitratechemical

EPA Code 1040 · Maximum Contaminant Level Exceedance

violations

EPA Limit

10 mg/L

Last Reading

10.5 MG/L

First Reported

Jan 2021

Most Recent

Jul 2025

What this violation means

Nitrate contamination is most acute in agricultural regions where fertilizer and animal waste leach into groundwater. The immediate risk is to formula-fed infants under 6 months — high nitrate levels prevent their blood from carrying oxygen, causing 'blue baby syndrome.' Pregnant women should also avoid high-nitrate water.

Recommended precautions

→Never give untreated high-nitrate water to infants — use bottled water for formula.
→Boiling does NOT remove nitrate. Boiling concentrates it.
→Reverse osmosis, ion exchange, or distillation are the only effective home treatments.
→Private well owners in farming areas should test annually for nitrate.

Read the complete guide to Nitrate

Leadchemical

EPA Code 5200 · Treatment Technique Violation

violations

EPA Limit

0.015 mg/L

Last Reading

—

First Reported

Oct 2024

Most Recent

Oct 2024

What this violation means

Lead is a potent neurotoxin with no safe exposure level. In drinking water it primarily enters via corroded lead service lines, lead-soldered copper pipes, and brass fixtures. Children under 6 and pregnant women face the highest risk because lead disrupts developing nervous and skeletal systems.

Recommended precautions

→Run cold tap water 30–120 seconds before drinking or cooking, especially after the tap has been unused for hours.
→Never cook with hot tap water — heat increases lead leaching from pipes.
→Use an NSF/ANSI 53 certified filter for lead removal (carbon block or reverse osmosis).
→If you have children, get blood lead levels tested by your pediatrician.

Read the complete guide to Lead

Haloacetic Acids (HAA5)disinfectant

EPA Code 2456 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.06 mg/L

Last Reading

.067 MG/L

First Reported

Jan 2021

Most Recent

Jul 2024

What this violation means

Haloacetic Acids (HAA5) are the second major group of disinfection byproducts after TTHMs. They form by the same mechanism — chlorine reacting with organic matter — and pose similar long-term cancer risks. Utilities are required to test quarterly at distribution-system locations to track HAA5 levels.

Recommended precautions

→Activated carbon filtration removes most HAA5.
→Reverse osmosis is highly effective.
→Unlike TTHMs, HAA5 do not significantly off-gas. Use treatment rather than aeration.
→Long-term ingestion is the primary concern, not short-term skin contact.

Read the complete guide to Haloacetic Acids (HAA5)

Total Trihalomethanes (TTHMs)disinfectant

EPA Code 2950 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.08 mg/L

Last Reading

.17 MG/L

First Reported

Jan 2021

Most Recent

Jan 2022

What this violation means

Total Trihalomethanes (TTHMs) form when chlorine reacts with naturally occurring organic matter — leaves, soil, algae — in source water. They are among the most commonly reported violations because utilities pulling from surface water (rivers, lakes, reservoirs) struggle to balance disinfection with byproduct formation. Long-term exposure has been linked to bladder cancer and adverse pregnancy outcomes.

Recommended precautions

→Activated carbon filters (pitcher, faucet, or under-sink) effectively reduce TTHMs.
→Letting water sit uncovered allows TTHMs to off-gas — leave a pitcher in the fridge for several hours.
→Shower with the bathroom fan on; TTHMs can volatilize into the air during hot showers.
→Boiling reduces TTHMs through volatilization, but only after extended boiling.

Read the complete guide to Total Trihalomethanes (TTHMs)

Source: EPA Safe Drinking Water Information System (SDWIS). Health-based violations only. Older violations may have been resolved; check your utility's most recent Consumer Confidence Report for current status.

Water Systems Serving FRESNO

COUNTRYSIDE CARE CENTER

PWSID: CA1000430

1,274 served

MANNING GARDENS CARE CENTER INC

PWSID: CA1000324

170 served

BRITZ/COLUSA

PWSID: CA1009023

85 served

BRITZ/FIVE POINTS

PWSID: CA1009179

76 served

EASTON ESTATES WATER COMPANY

PWSID: CA1000018

302 served

BAKMAN WATER-ROLLING HILLS

PWSID: CA2010009

1,107 served

1 violation

CAMDEN TRAILER PARK

PWSID: CA1000238

75 served

MEADOW LAKES CLUB

PWSID: CA1000056

240 served

CALIFORNIA STATE UNIVERSITY FRESNO

PWSID: CA1010339

41,000 served

FCSA 47 - QUAIL LAKE ESTATES

PWSID: CA1010055

1,988 served

FCSA 34 - MILLERTON NEW TOWN

PWSID: CA1000484

1,117 served

10 violations

FCSA 39 - A AND B

PWSID: CA1000471

395 served

FCSA 49 - FIVE POINTS

PWSID: CA1000546

440 served

5 violations

FCSA 44D - MONTE VERDI

PWSID: CA1000550

350 served

FCSA 43 - RAISIN CITY

PWSID: CA1000551

182 served

FCSA 10A - MANSIONETTE ESTATES

PWSID: CA1000554

81 served

8 violations

FCSA 44C - RIVERVIEW ESTATES

PWSID: CA1000555

34 served

FCWWD 41/SHAVER LAKE

PWSID: CA1010017

2,722 served

JUVENILE JUSTICE CAMPUS

PWSID: CA1000570

565 served

FCSA 34B - VENTANA HILLS

PWSID: CA1000574

48 served

FCSA 30 - EL PORVENIR

PWSID: CA1000019

241 served

10 violations

FCSA 05 - WILDWOOD ISLAND

PWSID: CA1000021

417 served

SHADY OAKS MOBILE HOME PARK LLC

PWSID: CA2000828

23 served

12 violations

WILDWOOD MOBILE HOME PK INC

PWSID: CA2000608

106 served

1 violation

SUNNYSIDE CONVALESCENT HOSP

PWSID: CA1000366

275 served

1 violation

JOHN HOVANNISIAN WATER SYSTEM

PWSID: CA2000647

80 served

1 violation

FCSA 14 - BELMONT MANOR

PWSID: CA1000023

115 served

FCSA 10 - CUMORAH KNOLLS

PWSID: CA1000039

132 served

FCWWD 37/MILE HIGH

PWSID: CA1000040

129 served

FCWWD 38/SKY HARBOUR

PWSID: CA1000041

185 served

FCWWD 40 - SHAVER SPRINGS

PWSID: CA1000042

196 served

FCWWD 42/ALLUVIAL & FANCHER

PWSID: CA1000078

291 served

1 violation

FCSA 32 - CANTUA CREEK

PWSID: CA1000359

462 served

10 violations

RIVERSTONE/ROOTCREEK WATER DISTRICT

PWSID: CA2010016

5,507 served

1 violation

PAPPAS & CO (MENDOTA)

PWSID: CA1009039

36 served

11 violations

MALAGA COUNTY WATER DISTRICT

PWSID: CA1010042

5,979 served

BELMONT WATER CORPORATION

PWSID: CA1000004

264 served

WESTSIDE HARVESTING

PWSID: CA1009214

72 served

1 violation

BAKMAN WATER COMPANY

PWSID: CA1010001

17,393 served

1 violation

WOODWARD BLUFFS MHP

PWSID: CA1000298

300 served

CITY OF FRESNO

PWSID: CA1010007

545,716 served

ELM COURT

PWSID: CA1000277

64 served

1 violation

What Can You Do?

✅ Request your utility's annual Consumer Confidence Report (CCR) — required by law.
✅ Use an NSF-certified water filter if violations involve lead, arsenic, or PFAS.
✅ Run cold water for 30 seconds before drinking if you have older plumbing (reduces lead).
✅ Check back monthly — we update data from the EPA every 30 days.

About this data

This overview reflects EPA SDWIS data published as of 2026-05-18. It covers active Community Water Systems (CWS) that exceeded federal Maximum Contaminant Levels during the past five-year EPA reporting window. For up-to-the-minute information, request a current Consumer Confidence Report from your utility, or review the EPA's public dashboard.

Frequently Asked Questions

Is FRESNO, California tap water safe to drink?▼

This city's water had numerous EPA violations in the last 5 years. Consider filtered water.

How many EPA violations does FRESNO have?▼

FRESNO has 75 EPA health-based water violations in the last 5 years across 42 water systems serving 630,234 people.

What contaminants have been found in FRESNO water?▼

The following EPA-regulated contaminants have been detected: 5200, 2456, 2950, 1040, 4006. View details about each contaminant, health effects, and recommended precautions above in the violations table.

Should I use a water filter in FRESNO?▼

Using an NSF-certified water filter is recommended if your area has violations involving lead, arsenic, or PFAS. For other contaminants, consult your local water utility. Check the annual Consumer Confidence Report (CCR) for detailed guidance.

What should I do if there are violations in FRESNO?▼

Request your water utility's annual Consumer Confidence Report (CCR), which is required by the EPA. Follow the utility's guidance on boil water advisories. Run cold water for 30 seconds before drinking if you have older plumbing. Use an NSF-certified filter if needed based on your water system's violations.