Is Modesto tap water safe to drink?

Yes but with caveats

Modesto's water meets EPA minimum standards but has some concerns including PFAS detected. Filtration is recommended for sensitive individuals.

70/100
Purity Score
2
Issues Found
6.2 GPG
Hardness
Detected
PFAS

2 Issues Detected in Modesto

PFAS (Forever Chemicals) Detected

PFAS are man-made chemicals that do not break down and accumulate in the body.

PFAS details for Modesto

Arsenic Approaching Limit (0.8 mg/L)

EPA limit is 0.010 mg/L.

Arsenic info for Modesto
California

953,509,535,195,354 · Modesto Reservoir and groundwater

Modesto, CA Water Quality Report

Moderate Risk Updated March 2026 218,464 residents
See Best Filters for Modesto
70
Purity Score

Contaminant Levels

PFAS
3 ppt
Lead
2.8 ppb
Nitrate
3 mg/L
Arsenic
0.8 mg/L
Hardness
6.2 gpg

Health Insights

  • 1
    PFAS have been identified in Modesto's water at 3 parts per trillion. A reverse osmosis system is the most reliable home treatment.

Score

70 /100
Moderate
"Good" threshold (70)

Modesto tap water is sourced from Modesto Reservoir and groundwater and treated by City of Modesto Water Division. PFAS forever chemicals have been detected. Overall purity score: 70/100 (Moderate). Updated for 2026.

Fix Your Water

Best filters matched to Modesto's 2 issues.

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Modesto Water FAQ

Is Modesto CA tap water safe to drink in 2026?
Modesto tap water meets EPA federal drinking water standards and scores 70/100 (Moderate) on PurityMap for 2026. PFAS forever chemicals have been detected at 3.0 ppt. An NSF-certified filter is strongly recommended. For most healthy adults the water is considered safe but point-of-use filtration adds an important layer of protection.
Does Modesto CA use chlorine or chloramine for disinfection?
Modesto uses chloramine as the primary disinfectant with a residual level of 1.0 ppm. Chloramine is harder to remove than free chlorine and requires a catalytic carbon or reverse osmosis filter. Standard Brita-style pitchers will NOT remove chloramine.
How hard is Modesto CA water and what is the TDS level?
Modesto water hardness is 6.2 grains per gallon (moderate) with a TDS of 255 ppm (fair). This level is unlikely to cause significant scale buildup in household plumbing.
Has PFAS been found in Modesto CA drinking water?
Yes. PFAS forever chemicals have been detected in Modesto water at approximately 3.0 ppt according to EPA UCMR5 monitoring data. A reverse osmosis or NSF P473-certified filter is the most effective residential solution.
What is the best water filter for Modesto?
Based on Modesto's water profile, we recommend the Clearly Filtered Water Pitcher. Modesto: PFAS detected or elevated lead risk. Reverse osmosis is the only residential technology proven to reduce both below detection limits. TDS will also drop significantly.

Nearby Reports

BakersfieldCalifornia — 55/100RiversideCalifornia — 58/100San BernardinoCalifornia — 58/100Moreno ValleyCalifornia — 58/100FontanaCalifornia — 58/100Chula VistaCalifornia — 61/100

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Data Sources

  • EPA SDWIS
  • EWG Tap Water Database
  • City of Modesto Water Division CCR
  • USGS monitoring data

PurityMap compiles public data. Updated March 2026.

© 2026 PurityMap. For informational purposes only.

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