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Tap water quality report

San Sebastian, PR

EPA monitoring detected 1 contaminant across the 5 water suppliers serving San Sebastian. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

5
water suppliers
37,430
people served
1
contaminants found
PR rankings Lead in PR PFAS in PR

What was found in San Sebastian's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Lead
0.0060 mg/L 40%
of the EPA limit 0.0150 mg/L
Main supplier: SAN SEBASTIAN · 25,752 people · 2015
Highest in the city: 0.0140 mg/L — ACUED. RURAL GUACIO · 340 people · 2023
4/5 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving San Sebastian

SupplierPopulation served
SAN SEBASTIAN 25,752
LAGO GUAJATACA 10,018
WILFREDO VALENTIN 1,239
ACUED. RURAL GUACIO 340
ACUEDUCTO RURAL GUADALUPE MARTI 81

Frequently asked questions about San Sebastian tap water

Is San Sebastian tap water safe to drink?

EPA testing detected 1 contaminant in the water serving San Sebastian. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve San Sebastian?

5 public water suppliers report drinking-water monitoring for San Sebastian, PR to the EPA. Each is listed above with its population served.

What contaminants are in San Sebastian's water?

The contaminants EPA monitoring detected in San Sebastian include Lead. The full list, with the level at the main supplier and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.