← Rancho Cucuamonga, CA

Tap water quality report

ZIP 91739 — Rancho Cucuamonga, CA

EPA monitoring across the 1 water supplier serving ZIP 91739 in Rancho Cucuamonga, CA detected 21 contaminants. A detection doesn't automatically mean the water is unsafe — see the highest level found below, with the EPA limit for each.

1
water supplier
211,069
people served
21
contaminants found

What was found in ZIP 91739

The highest level seen across the suppliers serving this ZIP, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate-Nitrite
990000 µg/L 9900%
of the EPA limit, in the worst sample — 10000 µg/L
1/1 SYR4
Nitrate
18758 µg/L 188%
of the EPA limit, in the worst sample — 10000 µg/L
1/1 SYR4
Fluoride
810 µg/L 20%
of the EPA limit 4000 µg/L
1/1 SYR4
TTHM
160 µg/L 200%
of the EPA limit, in the worst sample — 80 µg/L
1/1 SYR4
Barium
120 µg/L 6%
of the EPA limit 2000 µg/L
1/1 SYR4
Copper
70 µg/L 5.4%
of the EPA limit 1300 µg/L
1/1 SYR4
Dibromochloromethane
60 µg/L
No EPA limit set
1/1 SYR4
Bromodichloromethane
50 µg/L
No EPA limit set
1/1 SYR4
Bromoform
46 µg/L
No EPA limit set
1/1 SYR4
Chloroform
37 µg/L
No EPA limit set
1/1 SYR4
Total Haloacetic Acids (HAA5)
28 µg/L 47%
of the EPA limit 60 µg/L
1/1 SYR4
Combined Uranium
14.602 µg/L 49%
of the EPA limit 30 µg/L
1/1 SYR4
Dibromoacetic Acid
14.3 µg/L
No EPA limit set
1/1 SYR4
Trichloroacetic Acid
14 µg/L
No EPA limit set
1/1 SYR4
Dichloroacetic Acid
12 µg/L
No EPA limit set
1/1 SYR4
Arsenic
5.5 µg/L 55%
of the EPA limit 10 µg/L
1/1 SYR4
Monobromoacetic Acid
2.2 µg/L
No EPA limit set
1/1 SYR4
1,2-DIBROMO-3-CHLOROPROPANE
1.8 µg/L 900%
of the EPA limit, in the worst sample — 0.2000 µg/L
1/1 SYR4
Picloram
1.4 µg/L 0.3%
of the EPA limit 500 µg/L
1/1 SYR4
Dichloromethane
0.9800 µg/L 20%
of the EPA limit 5 µg/L
1/1 SYR4
Lead
0.0 mg/L 0%
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.

Water suppliers serving ZIP 91739

SupplierStatePopulation served
CUCAMONGA VALLEY WATER DISTRICT CA 211,069

Frequently asked questions about ZIP 91739 tap water

Is the tap water in ZIP 91739 safe to drink?

EPA testing detected 21 contaminants across the water suppliers serving ZIP 91739. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.

Which water suppliers serve ZIP 91739?

1 public water supplier report EPA drinking-water monitoring for ZIP 91739. Each is listed above with its population served.

What contaminants are in ZIP 91739's water?

EPA monitoring detected Nitrate-Nitrite, Nitrate, Fluoride, TTHM, Barium, and others across this ZIP's suppliers. The full list with levels and sources is above.