National Drinking Water Database
Nitrate & nitrite in Montana
Nitrate and nitrite enter water from fertilizer runoff, leaching from septic tanks, and erosion of natural deposits.
The Most Polluted Communities in Montana
576 water utilities reported detecting Nitrate & nitrite in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies
Ranked by highest average Nitrate & nitrite level
| Rank | System | Population Served | Positive test results of total reported tests | Average Level (Range) |
|---|---|---|---|---|
| 1 | Coffee Creek Water Company Coffee Creek, MT | 35 | 13 of 13 | 19.37 ppm (15.1 to 24.1 ppm) |
| 2 | King Ranch Colony Lewistown, MT | 55 | 13 of 13 | 16.39 ppm (11.6 to 20.8 ppm) |
| 3 | Rapelje Water Users Assn Rapelje, MT | 70 | 11 of 11 | 16 ppm (13.45 to 19.5 ppm) |
| 4 | Midway Colony MT | 75 | 1 of 1 | 8.46 ppm (8.46 ppm) |
| 5 | Crystal Springs Water System Billings, MT | 327 | 12 of 12 | 7.98 ppm (4.63 to 11.4 ppm) |
| 6 | River Grove Estates TR Ct Laurel, MT | 100 | 18 of 18 | 7.19 ppm (1.93 to 15 ppm) |
| 7 | Mobile City Home Park NO 2 Helena, MT | 300 | 3 of 3 | 6.8 ppm (6.7 to 7 ppm) |
| 8 | Mobile City Home Park NO 1 Helena, MT | 100 | 3 of 3 | 6.75 ppm (6.3 to 7.11 ppm) |
| 9 | Meadowland Hoa Kalispell, MT | 150 | 4 of 4 | 6.66 ppm (6.11 to 7.37 ppm) |
| 10 | Town of Denton Denton, MT | 301 | 21 of 21 | 6.65 ppm (0.29 to 22.53 ppm) |
Health Based Limits for Nitrate & nitrite
| Standard | Description | Level |
|---|---|---|
| Maximum Contaminant Limit (MCL) | The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency. | 10 ppm |
| Maximum Contaminant Limit Goal (MCLG) | A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency. | 10 ppm |
| California Public Health Goals | Defined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health. | 10 ppm |
Violation Summary for Nitrate & nitrite in Montana
Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Montana since 2004
| Violation Type | Number of Violations |
|---|---|
| Failure to monitor regularly | 209 |
| Over maximum contaminant level, Single Sample | 64 |
| Over maximum contaminant level, Average | 2 |