What was found in Arroyo Grande's water
The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate-Nitrite | 630000 µg/L 6300% of the EPA limit, in the worst sample — 10000 µg/L | 7/13 | SYR4 |
| Nitrate | 17800 µg/L 178% of the EPA limit, in the worst sample — 10000 µg/L | 11/13 | SYR4 |
| Fluoride | 820 µg/L 21% of the EPA limit 4000 µg/L | 10/13 | SYR4 |
| Barium | 250 µg/L 13% of the EPA limit 2000 µg/L | 6/13 | SYR4 |
| TTHM | 210 µg/L 263% of the EPA limit, in the worst sample — 80 µg/L | 10/13 | SYR4 |
| Chloroform | 160 µg/L No EPA limit set | 4/13 | SYR4 |
| Total Haloacetic Acids (HAA5) | 120 µg/L 200% of the EPA limit, in the worst sample — 60 µg/L | 4/13 | SYR4 |
| Copper | 94 µg/L 7.2% of the EPA limit 1300 µg/L | 2/13 | SYR4 |
| Dichloroacetic Acid | 73 µg/L No EPA limit set | 3/13 | SYR4 |
| Arsenic | 66 µg/L 660% of the EPA limit, in the worst sample — 10 µg/L | 6/13 | SYR4 |
| Lithium | 60 µg/L No EPA limit set | 1/13 | UCMR-5 |
| Selenium | 53 µg/L 106% of the EPA limit, in the worst sample — 50 µg/L | 10/13 | SYR4 |
| Bromodichloromethane | 50.3 µg/L No EPA limit set | 5/13 | SYR4 |
| Trichloroacetic Acid | 41 µg/L No EPA limit set | 3/13 | SYR4 |
| Dibromochloromethane | 38.7 µg/L No EPA limit set | 8/13 | SYR4 |
| Combined Uranium | 14.751 µg/L 49% of the EPA limit 30 µg/L | 5/13 | SYR4 |
| Dibromoacetic Acid | 13.2 µg/L No EPA limit set | 6/13 | SYR4 |
| Bromoform | 12.9 µg/L No EPA limit set | 8/13 | SYR4 |
| Lead | 7.4 µg/L 49% of the EPA limit 15 µg/L | 4/13 | SYR4 |
| Monochloroacetic Acid | 5.6 µg/L No EPA limit set | 2/13 | SYR4 |
| Cadmium | 2 µg/L 40% of the EPA limit 5 µg/L | 4/13 | SYR4 |
| Monobromoacetic Acid | 1.6 µg/L No EPA limit set | 1/13 | SYR4 |
| Toluene | 0.6200 µg/L 0.1% of the EPA limit 1000 µg/L | 1/13 | SYR4 |
| Lead | 0.0170 mg/L 113% above the EPA limit of 0.0150 mg/L | 13/13 | LCR |
| PFBS | 0.0110 µg/L No EPA limit set | 1/13 | UCMR-5 |
| PFOS | 0.0068 µg/L No EPA limit set | 1/13 | UCMR-5 |
| PFOA | 0.0058 µg/L No EPA limit set | 1/13 | UCMR-5 |
| PFHXS | 0.0055 µg/L No EPA limit set | 1/13 | UCMR-5 |
| Pfpea | 0.0045 µg/L No EPA limit set | 1/13 | UCMR-5 |
| Pfhxa | 0.0035 µg/L No EPA limit set | 1/13 | UCMR-5 |
Water suppliers serving Arroyo Grande
| Supplier | Population served |
|---|---|
| CITY OF ARROYO GRANDE UTILITIES DIVISION | 17,963 |
| WOODLANDS DEVELOPMENT | 3,862 |
| MESA DUNES MOBILE HOME ESTATES | 600 |
| WOODLAND PARK MUTUAL WATER CO | 538 |
| CANYON CREST MUTUAL BENEFIT WC | 133 |
| EDNA VALLEY RANCH EAST | 132 |
| VARIAN RANCH MUTUAL WATER | 105 |
| KEN MAR GARDENS | 84 |
| LAGUNA NEGRA MUTUAL WATER CO. | 80 |
| H2O, INC | 70 |
| COUNTRY HILLS ESTATES | 60 |
| RANCHO NIPOMO WATER COMPANY | 44 |
| TERRA DE ORO WATER COMPANY | 38 |
Frequently asked questions about Arroyo Grande tap water
Is Arroyo Grande tap water safe to drink?
EPA testing detected 30 contaminants in the water serving Arroyo Grande. 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 Arroyo Grande?
13 public water suppliers report drinking-water monitoring for Arroyo Grande, California to the EPA. Each is listed above with its population served.
What contaminants are in Arroyo Grande's water?
The contaminants EPA monitoring detected in Arroyo Grande include Nitrate-Nitrite, Nitrate, Fluoride, Barium, TTHM. 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.