CITY WATER REPORT
Is Hillsborough Tap Water Safe? 2026 Water Quality Report
TOWN OF HILLSBOROUGH serves Hillsborough · 11,766 residents.
- Utility
- TOWN OF HILLSBOROUGH
- Population served
- 11,766
- Water source
- Surface water
- Disinfectant
- Pending utility report
- Hardness
- Pending utility report
Perfluorooctanoic acid (PFOA): not detected (limit 4.0 ng/L).
About this score The Purity Score summarises the public records PurityMap analysed for Hillsborough. It is not a laboratory test of the water at your tap.
What the record showsGreen means a contaminant was measured and is within its benchmark: a fact about that measurement, not an overall verdict. Anything not yet monitored stays unknown.
TOWN OF HILLSBOROUGH (EPA PWSID CA4110016) delivers surface water to 11,766 residents. This report reflects 3 federally regulated PFAS result(s) from the 2024 UCMR5 round and the latest Lead & Copper Rule 90th-percentile result. Water hardness and disinfectant type are pending the utility's own annual report.
Your water system
resolution confirmed
- TOWN OF HILLSBOROUGH (serves most of the city)
TOWN OF HILLSBOROUGH is the primary municipal supplier for most Hillsborough addresses. Confirm your supplier on your utility bill.
TOWN OF HILLSBOROUGH is the public system on record for this city. This identifies which utility serves the city. Confirm yours on your water bill before acting on a specific finding.
What stands out in Hillsborough
Each row links to a dated measurement in the supplier profile. A missing measurement is never shown as a non-detect.
What this data doesn’t tell you
Public water-system monitoring reflects the system, not the water at an individual household tap at a given moment. Home plumbing, fixtures, storage, sampling location and timing can all change what actually reaches your glass.
The data behind this report
| Contaminant | Result | Benchmark | Sampled | Source |
|---|---|---|---|---|
| Perfluorooctanoic acid (PFOA) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | 2024 | UCMR5 Analytical Results: TOWN OF HILLSBOROUGH (CA4110016) |
| Perfluorooctane sulfonic acid (PFOS) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | 2024 | UCMR5 Analytical Results: TOWN OF HILLSBOROUGH (CA4110016) |
| Perfluorohexane sulfonic acid (PFHxS) | < 10 ng/L | 10.0 ng/L federal MCL (2024) | 2024 | UCMR5 Analytical Results: TOWN OF HILLSBOROUGH (CA4110016) |
| Lead (90th percentile) | 0 µg/L | 15 µg/L federal action level | 2023-2025 | Lead & Copper Rule 90th-percentile: TOWN OF HILLSBOROUGH (CA4110016) |
Perfluorooctanoic acid (PFOA)
- Result
- < 4 ng/L
- Benchmark
- 4.0 ng/L federal MCL (2024)
- Sampled
- 2024
Perfluorooctane sulfonic acid (PFOS)
- Result
- < 4 ng/L
- Benchmark
- 4.0 ng/L federal MCL (2024)
- Sampled
- 2024
Perfluorohexane sulfonic acid (PFHxS)
- Result
- < 10 ng/L
- Benchmark
- 10.0 ng/L federal MCL (2024)
- Sampled
- 2024
Lead (90th percentile)
- Result
- 0 µg/L
- Benchmark
- 15 µg/L federal action level
- Sampled
- 2023-2025
Every value is the published result from the cited public record. A reporting limit is the lowest level the method could reliably quantify; a non-detect is not a guarantee of zero.
What can you do about it?To reduce exposure to what was reported in Hillsborough, these treatment technologies are relevant to the contaminants found here.
- Reverse osmosis
- NSF/ANSI 53 lead-certified filters
- Replacing lead service lines
Understand water treatment technologies, then the specific products below are matched to these findings.
Recommended solutions
NSF/ANSI 53 lead-reduction filter (optional)
leadOur pick: Brita Large 10-Cup Elite Water Filter Pitcher, WQA NSF/ANSI Certified, Reduces 99% of Lead, Microplastics, & 30 Contaminants, BPA-Free, Removes Chlorine Taste & Odor, 1 Filter Included, White
Recommended because There is no safe level of lead, and older home plumbing can add it at the tap.
Recommendations are matched to the published findings first; the commercial offer is looked up afterwards and never changes which products qualify. As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Frequently asked questions
Who provides tap water in Hillsborough?
TOWN OF HILLSBOROUGH (PWS ID CA4110016) is the public water system on record for Hillsborough, California. Confirm the utility on your water bill before acting on a specific finding.
Where does Hillsborough get its drinking water?
Surface water (primary source of record in EPA SDWIS).
What does the latest Hillsborough water report show?
Across the tracked parameters, PurityMap's current record for Hillsborough shows 0 contaminants measured above their benchmark and 4 within benchmark. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass.
Is there lead in Hillsborough's tap water?
In Hillsborough, lead is detected but within its action level in the published record. Lead can still enter water from household plumbing after it leaves the system, so a system result cannot rule out an individual tap. A certified home test is the only way to know yours.
Are PFAS "forever chemicals" in Hillsborough's water?
PFAS compounds appear in Hillsborough's published record; the findings show each one's measured state and how it compares to its benchmark.
Sources
Methodology: how we analyze water. Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
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- Systems published
- 1 of 1
- Latest sample on record
- 2024 (PFAS) / LCR (lead)