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Tap water quality report

San Luis, AZ

EPA monitoring detected 21 contaminants across the 1 water supplier serving San Luis. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

1
water supplier
39,705
people served
21
contaminants found
Arizona rankings Lead in Arizona PFAS in Arizona

What was found in San Luis's water

The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Copper
1610 µg/L 124%
of the EPA limit, in the worst sample — 1300 µg/L
 1/1 SYR4
Nitrate
1210 µg/L 12%
of the EPA limit 10000 µg/L
 1/1 SYR4
Fluoride
290 µg/L 7.2%
of the EPA limit 4000 µg/L
 1/1 SYR4
Nitrate-Nitrite
188 µg/L 1.9%
of the EPA limit 10000 µg/L
 1/1 SYR4
Barium
120 µg/L 6%
of the EPA limit 2000 µg/L
 1/1 SYR4
Lithium
103 µg/L
No EPA limit set
 1/1 UCMR-5
TTHM
102 µg/L 127%
of the EPA limit, in the worst sample — 80 µg/L
 1/1 SYR4
Dibromochloromethane
42.5 µg/L
No EPA limit set
 1/1 SYR4
Total Haloacetic Acids (HAA5)
25.8 µg/L 43%
of the EPA limit 60 µg/L
 1/1 SYR4
Di(2-ethylhexyl) Phthalate
13.7 µg/L 228%
of the EPA limit, in the worst sample — 6 µg/L
 1/1 SYR4
Dibromoacetic Acid
9.2 µg/L
No EPA limit set
 1/1 SYR4
Lead
8.27 µg/L 55%
of the EPA limit 15 µg/L
 1/1 SYR4
Selenium
5.2 µg/L 10%
of the EPA limit 50 µg/L
 1/1 SYR4
Combined Radium (-226 And -228)
4.64 pCi/L 93%
of the EPA limit 5 pCi/L
 1/1 SYR4
Arsenic
2.3 µg/L 23%
of the EPA limit 10 µg/L
 1/1 SYR4
Gross Alpha, Excl. Radon And U
2.3 pCi/L 15%
of the EPA limit 15 pCi/L
 1/1 SYR4
Thallium, Total
0.8500 µg/L 43%
of the EPA limit 2 µg/L
 1/1 SYR4
Beryllium, Total
0.5300 µg/L 13%
of the EPA limit 4 µg/L
 1/1 SYR4
Antimony, Total
0.2000 µg/L 3.3%
of the EPA limit 6 µg/L
 1/1 SYR4
Mercury
0.0700 µg/L 3.5%
of the EPA limit 2 µg/L
 1/1 SYR4
Lead
0.0010 mg/L 6.7%
of the EPA limit 0.0150 mg/L
 1/1 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 single worst sample on record — 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 Luis

SupplierPopulation served
SAN LUIS CITY OF 39,705

Frequently asked questions about San Luis tap water

Is San Luis tap water safe to drink?

EPA testing detected 21 contaminants in the water serving San Luis. 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 Luis?

1 public water supplier report drinking-water monitoring for San Luis, Arizona to the EPA. Each is listed above with its population served.

What contaminants are in San Luis's water?

The contaminants EPA monitoring detected in San Luis include Copper, Nitrate, Fluoride, Nitrate-Nitrite, Barium. The full list, with the highest level found 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.