CheckPFAS

ZIP 91784 · California

Upland, CA

High Risk
See the full Upland overview — all utilities & ZIP codes →

7 compounds detected

Above EPA drinking water limits

PFOA Exceeds limit
12.90 ppt (323% of MCL)
→ 3.2× MCL
0 MCL: 4 ppt 12.9 ppt
PFOS Exceeds limit
10.40 ppt (260% of MCL)
→ 2.6× MCL
0 MCL: 4 ppt 10.4 ppt
PFHxS
3.70 ppt (37% of MCL)
0 MCL: 10 ppt 15 ppt
PFHxA no federal limit
8.40 ppt
0 12.7 ppt
PFPeA no federal limit
6.40 ppt
0 9.7 ppt
PFBS no federal limit
5.10 ppt
0 7.7 ppt
PFHpA no federal limit
4.60 ppt
0 6.9 ppt
Above EPA limit Below EPA limit No federal limit EPA MCL

Above EPA Limits

2 compounds exceed EPA Maximum Contaminant Levels in water serving this ZIP code. Standard pitcher filters like Brita do not remove PFAS. See filter recommendations below.

PFAS Detected
10
Above EPA Limits
2
Water Systems
2
Highest % of MCL
323%

Plain English

01What this means for you

One or more PFAS compounds were measured above the EPA's enforceable drinking water limit at a utility serving ZIP 91784. The EPA set these limits because long-term exposure at higher concentrations is associated with health effects including immune suppression, thyroid changes, and cancer risk increases. Standard pitcher filters (Brita, PUR) are not certified to remove PFAS. The most reliable at-home options are under-sink reverse osmosis systems or activated carbon block filters with an NSF/ANSI 58 certification specifically listing PFOA/PFOS reduction. Your water utility is required to bring levels into compliance by 2029 — filtering at the tap is the practical interim step if you'd like additional protection now.

What to do next

02Three concrete steps

  1. 01

    Install a certified filter

    A reverse osmosis or NSF/ANSI 58-certified carbon block at your kitchen tap is the most reliable solution. Standard pitcher filters (Brita, PUR) don't remove PFAS unless explicitly certified for it. See certified filter picks →

  2. 02

    Read your utility's CCR

    Your water utility publishes an annual Consumer Confidence Report covering the previous year's water quality, including their PFAS treatment plan if any. More detailed than this site's summary. How to read a CCR →

  3. 03

    Reduce other exposure routes

    Water isn't the only input. Replace badly-scratched non-stick pans, skip microwave popcorn bags and greaseproof fast-food wrappers, and choose stainless or cast iron cookware. Full action plan on the FAQ →

Filter Recommendations

Find the right filter for your water
See our tested & reviewed PFAS-certified filters, ranked by CheckPFAS Score

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02GSWC - CLAREMONT

High Risk

PWSID · CA1910024

Water Type
Groundwater
PFAS Detected
7
Above MCL
2
State
California
Data Period
2023–2025

PFAS test results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFOA
Perfluorooctanoic acid
12.90ppt
323% of limit
4 pptExceeds MCL
PFOS
Perfluorooctane sulfonic acid
10.40ppt
260% of limit
4 pptExceeds MCL
PFHxS
Perfluorohexane sulfonic acid
3.70ppt
37% of limit
10 pptBelow limit
PFHxA
Perfluorohexanoic acid
8.40pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
6.40pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
5.10pptNo federal limitUnregulated
PFHpA
Perfluoroheptanoic acid
4.60pptNo federal limitUnregulated

03UPLAND, CITY OF

Low Level

PWSID · CA3610050

Water Type
Groundwater
PFAS Detected
3
Above MCL
0
State
California
Data Period
2023–2025

PFAS test results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFPeA
Perfluoropentanoic acid
5.70pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
5.50pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
3.00pptNo federal limitUnregulated

Note: ZIP code 91784 is served by 2 separate water utilities. Results above show data for each system independently.

Source & Methodology

About this data

Source
EPA UCMR 5
Data released
January 2026
Sampling period
January 2023 – December 2025
Systems tested
~10,000 public water systems
Water systems (PWSID)
CA1910024 · CA3610050
Detection threshold (MRL)
~1.5–2 ppt

Values shown are the highest single-sample concentration measured at entry points to the distribution system. Results reflect water quality at the treatment plant — aging pipes, building plumbing, and on-site storage can affect what actually reaches your tap. "Not detected" means below the MRL, not literally zero.

View raw EPA UCMR 5 occurrence data →

Related

More resources for your area

  1. 01

    How to read your utility's CCR

    Decode your annual Consumer Confidence Report

  2. 02

    On a private well?

    PFAS testing guide for well owners — EPA rules don't apply

  3. 03

    All water systems in California

    Compare utilities statewide

  4. 04

    Which filter removes PFAS?

    Compare every method by removal rate & NSF certification

  5. 05

    PFAS health effects

    What the science shows, condition by condition

  6. 06

    PFAS compound guide

    Health effects & EPA limits for each compound