What was found in Boise'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 | 12100 µg/L 121% of the EPA limit, in the worst sample — 10000 µg/L | 24/25 | SYR4 |
| Nitrate-Nitrite | 4700 µg/L 47% of the EPA limit 10000 µg/L | 19/25 | SYR4 |
| Fluoride | 3050 µg/L 76% of the EPA limit 4000 µg/L | 22/25 | SYR4 |
| Barium | 500 µg/L 25% of the EPA limit 2000 µg/L | 15/25 | SYR4 |
| TTHM | 84 µg/L 105% of the EPA limit, in the worst sample — 80 µg/L | 7/25 | SYR4 |
| Total Haloacetic Acids (HAA5) | 60 µg/L 100% of the EPA limit 60 µg/L | 5/25 | SYR4 |
| Chloroform | 48 µg/L No EPA limit set | 2/25 | SYR4 |
| Combined Uranium | 42 µg/L 140% of the EPA limit, in the worst sample — 30 µg/L | 24/25 | SYR4 |
| Nitrite | 30 µg/L 3% of the EPA limit 1000 µg/L | 2/25 | SYR4 |
| Arsenic | 26 µg/L 260% of the EPA limit, in the worst sample — 10 µg/L | 14/25 | SYR4 |
| Lithium | 24.3 µg/L No EPA limit set | 2/25 | UCMR-5 |
| Gross Alpha, Excl. Radon And U | 23.7 pCi/L 158% of the EPA limit, in the worst sample — 15 pCi/L | 9/25 | SYR4 |
| Tetrachloroethylene | 11.5 µg/L 230% of the EPA limit, in the worst sample — 5 µg/L | 1/25 | SYR4 |
| Copper | 10 µg/L 0.8% of the EPA limit 1300 µg/L | 1/25 | SYR4 |
| Chromium | 6 µg/L 6% of the EPA limit 100 µg/L | 4/25 | SYR4 |
| Gross Beta Particle Activity | 4.9 pCi/L No EPA limit set | 1/25 | SYR4 |
| Bromodichloromethane | 4.8 µg/L No EPA limit set | 2/25 | SYR4 |
| Dibromochloromethane | 4.7 µg/L No EPA limit set | 3/25 | SYR4 |
| Bromoform | 3.4 µg/L No EPA limit set | 3/25 | SYR4 |
| Monochloroacetic Acid | 3 µg/L No EPA limit set | 1/25 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 2.4 µg/L 40% of the EPA limit 6 µg/L | 2/25 | SYR4 |
| Trichloroethylene | 2.31 µg/L 46% of the EPA limit 5 µg/L | 2/25 | SYR4 |
| Combined Radium (-226 And -228) | 2.3 pCi/L 46% of the EPA limit 5 pCi/L | 6/25 | SYR4 |
| 1,1-Dichloroethylene | 1.1 µg/L 16% of the EPA limit 7 µg/L | 1/25 | SYR4 |
| Dibromoacetic Acid | 0.9600 µg/L No EPA limit set | 1/25 | SYR4 |
| cis-1,2-Dichloroethylene | 0.6000 µg/L 0.9% of the EPA limit 70 µg/L | 1/25 | SYR4 |
| Di(2-ethylhexyl) Adipate | 0.4260 µg/L 0.1% of the EPA limit 400 µg/L | 1/25 | SYR4 |
| Atrazine | 0.1560 µg/L 5.2% of the EPA limit 3 µg/L | 1/25 | SYR4 |
| PFNA | 0.0510 µg/L No EPA limit set | 1/25 | UCMR-5 |
| Ethylene Dibromide | 0.0240 µg/L 48% of the EPA limit 0.0500 µg/L | 1/25 | SYR4 |
| Lead | 0.0110 mg/L 73% of the EPA limit 0.0150 mg/L | 25/25 | LCR |
| PFOS | 0.0098 µg/L No EPA limit set | 1/25 | UCMR-5 |
| PFOA | 0.0059 µg/L No EPA limit set | 1/25 | UCMR-5 |
| PFHXS | 0.0055 µg/L No EPA limit set | 1/25 | UCMR-5 |
| Pfpea | 0.0054 µg/L No EPA limit set | 1/25 | UCMR-5 |
| Pfhxa | 0.0052 µg/L No EPA limit set | 1/25 | UCMR-5 |
| PFBS | 0.0040 µg/L No EPA limit set | 1/25 | UCMR-5 |
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 Boise
| Supplier | Population served |
|---|---|
| VEOLIA WATER IDAHO | 264,978 |
| CAPITOL WATER CORP | 9,000 |
| IDOC SBX COMPLEX | 3,309 |
| IDOC IDAHO STATE CORRECTIONAL CENTER | 2,204 |
| HILLSDALE ESTATES HOMEOWNERS ASSN | 800 |
| RUSTIC ACRES MOBILE HOME PARK | 540 |
| IDOC MOUNTAIN VIEW TRANSFORMATION CENTER | 456 |
| FLYING H TRAILER RANCH | 430 |
| EAGLE GLEN HOMEOWNERS ASSN INC | 300 |
| WYMOSA WATER ASSN INC | 280 |
| PARADISE ESTATES WATER CORP | 273 |
| WEST MEADOWS ESTATES | 270 |
| KLUGHERZ WATER CORP | 200 |
| EAGLE MHC | 135 |
| LINDA VISTA MOBILE HOME PARK | 125 |
| KRIZVIEW PARK | 120 |
| HAMPTON HOMES HOME OWNERS ASSN | 95 |
| FRANKLIN DOMESTIC WATER USERS | 75 |
| STANLEY POND INC | 72 |
| MALAD AND HILTON WATER COMPANY INC. | 70 |
| ISLAND VILLAGE MOBILE HOME PARK | 70 |
| AMY TRAILER PARK | 46 |
| ANDERSON CIRCLE WATER CORP | 40 |
| RIM ACRES MUTUAL WATER | 31 |
| RILEY TRAILER PARK | 30 |
Frequently asked questions about Boise tap water
Is Boise tap water safe to drink?
EPA testing detected 37 contaminants in the water serving Boise. 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 Boise?
25 public water suppliers report drinking-water monitoring for Boise, Idaho to the EPA. Each is listed above with its population served.
What contaminants are in Boise's water?
The contaminants EPA monitoring detected in Boise include Nitrate, Nitrate-Nitrite, 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.