Nitrate (as N) in Treasure Valley drinking water
134 of 154 systems that tested for it in the last 36 months detected it; 43 are above the limit, elevated, or an aesthetic issue. Nitrate (as N) is an inorganic contaminant. Certified filters are in the list.
Idaho DEQ has designated Nitrate Priority Areas across the Treasure Valley, including parts of Canyon County and southwest Ada County. Private wells in irrigated agricultural areas are the main concern.
| System | County | 36 mo max | Latest | Status | Last sample |
|---|---|---|---|---|---|
| Mountain Home Air Force Base | Elmore | 18.40ppm | 11.40ppm | Above limit | 2026-06-25 |
| Canyon Creek Mobile Home Park | Elmore | 13.20ppm | 2.50ppm | Above limit | 2026-09-08 |
| Drake Subdivision | Canyon | 12.20ppm | 12.20ppm | Above limit | 2025-12-26 |
| D and S Purple Sage Ranchettes | Canyon | 12.00ppm | 9.54ppm | Above limit | 2026-07-21 |
| Woodview Acres Property Owners | Canyon | 11.40ppm | 2.60ppm | Above limit | 2026-06-29 |
| Purple Sage Community | Canyon | 10.10ppm | 8.40ppm | Above limit | 2026-01-06 |
| Sunnyridge I Subdivision | Canyon | 10.10ppm | ND | Above limit | 2026-06-16 |
| Maverick Subdivision Lasher Construction | Canyon | 9.69ppm | 3.57ppm | Elevated | 2026-04-08 |
| Leisure Heights Homeowners Association | Canyon | 9.40ppm | 3.50ppm | Elevated | 2025-11-17 |
| City of Melba | Canyon | 8.50ppm | 8.20ppm | Elevated | 2026-08-03 |
| Trinity Estates Water Users Association | Elmore | 8.50ppm | 7.10ppm | Elevated | 2026-08-20 |
| Apache Heights Subdivision (2) | Canyon | 8.00ppm | 8.00ppm | Elevated | 2026-06-09 |
| Sawtooth Estates Water Users | Elmore | 7.90ppm | 4.80ppm | Elevated | 2026-08-20 |
| Locust Subdivision | Canyon | 7.80ppm | 7.80ppm | Elevated | 2026-06-09 |
| Town and Country Water Users Association | Elmore | 7.73ppm | 6.53ppm | Elevated | 2026-07-06 |
| Valley View Water | Canyon | 7.34ppm | 6.78ppm | Elevated | 2026-07-24 |
| Gem State Academy | Canyon | 6.90ppm | 3.00ppm | Elevated | 2026-01-21 |
| Sunlight Terrace | Canyon | 6.60ppm | 5.90ppm | Elevated | 2026-08-19 |
| Rich Subdivision | Canyon | 6.60ppm | 6.60ppm | Elevated | 2026-03-11 |
| Sunnyridge Subdivision 2 | Canyon | 6.60ppm | 6.10ppm | Elevated | 2025-09-16 |
| Veolia Water Idaho | Ada | 6.50ppm | 0.90ppm | Elevated | 2026-08-27 |
| M & T Water Corp. | Canyon | 6.40ppm | 6.10ppm | Elevated | 2026-04-10 |
| City of Nampa | Canyon | 6.30ppm | 6.00ppm | Elevated | 2026-08-19 |
| Karcher Ranchette Water Corp. | Canyon | 6.20ppm | 5.30ppm | Elevated | 2025-11-24 |
| City of Glenns Ferry | Elmore | 6.10ppm | 4.30ppm | Elevated | 2026-07-21 |
| Simplot Livestock Company Grandview | Elmore | 6.10ppm | 1.30ppm | Elevated | 2026-09-01 |
| Wilderness Ranch Owners Association Inc. | Boise | 6.08ppm | 1.28ppm | Elevated | 2026-04-07 |
| Greenhills Estates 3 | Ada | 6.00ppm | 6.00ppm | Elevated | 2026-02-23 |
| Sunnyridge 3 Water Corp. | Canyon | 5.80ppm | 5.70ppm | Elevated | 2026-06-08 |
| Country Meadows Subdivision | Canyon | 5.80ppm | 5.50ppm | Elevated | 2025-11-18 |
| Grouse Point Water Company LLC | Ada | 5.70ppm | ND | Elevated | 2025-12-04 |
| Meridian Water Department | Ada | 5.60ppm | 0.80ppm | Elevated | 2026-06-24 |
| Belle Aire Acres 2 | Canyon | 5.60ppm | 5.50ppm | Elevated | 2026-02-23 |
| Caldwell Housing Authority | Canyon | 5.50ppm | 4.90ppm | Elevated | 2025-06-16 |
| Hamilton Place | Elmore | 5.50ppm | 5.50ppm | Elevated | 2026-01-20 |
| M and M Mountain View Subdivision Em2 | Canyon | 5.50ppm | 5.10ppm | Elevated | 2026-08-19 |
| Pleasant Acres Mobile Home Park | Elmore | 5.30ppm | 4.20ppm | Elevated | 2026-01-20 |
| Hammett Haven Apartments | Elmore | 5.30ppm | 5.30ppm | Elevated | 2023-10-31 |
| Lakeridge Second Subdivision | Canyon | 5.25ppm | 4.78ppm | Elevated | 2025-08-13 |
| Indian Village | Canyon | 5.10ppm | 5.00ppm | Elevated | 2025-12-02 |
| Sunnyridge Property Owners | Canyon | 5.10ppm | 5.10ppm | Elevated | 2026-06-11 |
| New Horizons Water Inc. | Elmore | 5.01ppm | 4.73ppm | Elevated | 2025-08-20 |
| City of Kuna | Ada | 5.00ppm | ND | Elevated | 2026-08-13 |
| City of Eagle (Eastern Zone) | Ada | 4.60ppm | 3.40ppm | Detected | 2026-01-21 |
| Paradise Estates Water Corp. | Ada | 4.40ppm | 4.20ppm | Detected | 2025-12-10 |
| Riley Trailer Park | Ada | 4.30ppm | 4.30ppm | Detected | 2026-04-07 |
| Rolling Hills Estates Water Company | Canyon | 4.20ppm | ND | Detected | 2025-07-14 |
| Horseshu Vue Ranch Subdivision | Boise | 4.20ppm | 3.70ppm | Detected | 2025-12-16 |
| Capitol Water Corp. | Ada | 4.10ppm | ND | Detected | 2026-07-14 |
| Dry Creek Water Company LLC | Ada | 4.10ppm | 1.50ppm | Detected | 2025-11-11 |
| Desert View Estates Water Corp. | Ada | 4.10ppm | 4.10ppm | Detected | 2026-06-22 |
| Ok Water Association | Canyon | 4.10ppm | 3.90ppm | Detected | 2026-05-06 |
| Rivervine Subdivision | Ada | 4.10ppm | ND | Detected | 2025-12-22 |
| Shamrock Villa Water Association | Canyon | 4.00ppm | 3.90ppm | Detected | 2025-10-07 |
| Lindenwood Water Association | Canyon | 4.00ppm | 2.90ppm | Detected | 2026-04-14 |
| Eagle West Subdivision Water Association | Ada | 3.90ppm | 3.20ppm | Detected | 2026-03-24 |
| Malad and Hilton Water Company Inc. | Ada | 3.90ppm | 3.90ppm | Detected | 2026-02-26 |
| Linda Vista Mobile Home Park | Ada | 3.70ppm | 3.70ppm | Detected | 2026-03-10 |
| Stecher Mutual Water Company | Canyon | 3.70ppm | 3.00ppm | Detected | 2026-01-14 |
| IDOC Idaho State Correctional Center | Ada | 3.50ppm | 2.62ppm | Detected | 2025-08-19 |
| Twin Bridges Subdivision | Canyon | 3.50ppm | 3.50ppm | Detected | 2025-12-02 |
| Westview Shervik Subdivision | Canyon | 3.40ppm | 3.40ppm | Detected | 2026-02-23 |
| IDOC SBX Complex | Ada | 3.31ppm | 3.31ppm | Detected | 2026-08-25 |
| Clark Theurer Water Association | Canyon | 3.20ppm | 3.20ppm | Detected | 2026-06-29 |
| Verde Hills Water Users Association Inc. | Canyon | 3.10ppm | 1.80ppm | Detected | 2026-02-23 |
| Picket Corral Owners Association | Gem | 3.10ppm | 2.90ppm | Detected | 2025-11-10 |
| Covert Water Users Association | Canyon | 3.03ppm | 1.00ppm | Detected | 2026-05-15 |
| Camelot Water Association Inc. | Canyon | 3.00ppm | 2.90ppm | Detected | 2025-11-24 |
| Skyline Water Association | Canyon | 3.00ppm | 2.90ppm | Detected | 2026-04-14 |
| Arrowrock Ranch | Ada | 2.90ppm | 2.30ppm | Detected | 2025-12-04 |
| Anderson Circle Water Corp. | Ada | 2.90ppm | 2.70ppm | Detected | 2026-07-30 |
| Silver Sage Real Property Owners Association | Elmore | 2.87ppm | 2.25ppm | Detected | 2025-07-15 |
| Summerwind Water Users | Elmore | 2.70ppm | 1.30ppm | Detected | 2026-05-12 |
| Willowbrook Estates Property Owners | Ada | 2.70ppm | 1.10ppm | Detected | 2025-11-25 |
| Evans Water Corp. | Ada | 2.60ppm | 0.90ppm | Detected | 2025-03-04 |
| Northridge Estates Water Association | Canyon | 2.50ppm | 2.50ppm | Detected | 2026-03-11 |
| City of Mountain Home | Elmore | 2.40ppm | 0.90ppm | Detected | 2026-08-26 |
| Sierra Water Corp. | Ada | 2.40ppm | 2.30ppm | Detected | 2026-06-15 |
| City of Caldwell | Canyon | 2.30ppm | 0.30ppm | Detected | 2026-04-15 |
| Eagle MHC | Ada | 2.20ppm | 2.20ppm | Detected | 2026-04-16 |
| Featherville Townsite Water Corp. | Elmore | 2.20ppm | ND | Detected | 2026-03-15 |
| Wymosa Water Association Inc. | Ada | 2.10ppm | 1.80ppm | Detected | 2025-11-19 |
| Amy Trailer Park | Ada | 2.10ppm | 2.10ppm | Detected | 2026-03-02 |
| Silver Spur Subdivision | Canyon | 2.10ppm | 1.80ppm | Detected | 2025-12-22 |
| Flying H Trailer Ranch | Ada | 2.00ppm | 1.90ppm | Detected | 2026-03-10 |
| Shalimar Subdivision | Canyon | 2.00ppm | 2.00ppm | Detected | 2026-04-10 |
| Krizview Park | Ada | 1.80ppm | 1.60ppm | Detected | 2026-03-10 |
| Oakleaf Subdivision | Elmore | 1.80ppm | 1.80ppm | Detected | 2026-01-13 |
| Hi View Water | Ada | 1.80ppm | 1.80ppm | Detected | 2025-05-07 |
| Terrace Water Corp. Inc. | Ada | 1.70ppm | 1.40ppm | Detected | 2025-11-20 |
| Mores Creek Rim Ranch Water District | Boise | 1.64ppm | 1.64ppm | Detected | 2025-12-02 |
| Osprey | Boise | 1.64ppm | 1.64ppm | Detected | 2025-12-02 |
| Lakeview Hills Water Users Association | Canyon | 1.60ppm | 1.60ppm | Detected | 2025-12-02 |
| Dahl Subdivision | Canyon | 1.60ppm | 1.60ppm | Detected | 2025-12-11 |
| Duquette Pines Homeowners Association | Boise | 1.54ppm | 0.41ppm | Detected | 2026-08-12 |
| Star Sewer and Water District Water System | Ada | 1.50ppm | ND | Detected | 2026-09-08 |
| Scottys Mobile Home Park | Ada | 1.50ppm | 1.00ppm | Detected | 2026-04-16 |
| Forrey Heights | Ada | 1.40ppm | 1.40ppm | Detected | 2026-01-14 |
| Lansing Meadows | Canyon | 1.30ppm | 1.00ppm | Detected | 2025-11-18 |
| Owyhee Village Subdivision Water Association Inc. | Canyon | 1.30ppm | 1.30ppm | Detected | 2026-01-14 |
| Rivers Point Property Owners Association | Boise | 1.20ppm | ND | Detected | 2026-06-14 |
| Northside Estates HOA Inc. | Canyon | 1.20ppm | 1.20ppm | Detected | 2026-02-09 |
| Mountain Sage | Elmore | 1.20ppm | 1.10ppm | Detected | 2026-01-06 |
| West Meadows Estates | Ada | 1.10ppm | 1.10ppm | Detected | 2026-05-14 |
| Eagle Point Community | Ada | 1.10ppm | 0.90ppm | Detected | 2026-03-24 |
| Par Estates Homeowners Association | Canyon | 1.10ppm | 1.10ppm | Detected | 2025-12-18 |
| Burnie Subdivision | Canyon | 1.10ppm | 1.00ppm | Detected | 2026-01-14 |
| Camas Estates Water Users | Elmore | 1.10ppm | 1.10ppm | Detected | 2026-06-17 |
| Chaparral Water Association | Ada | 1.00ppm | 0.90ppm | Detected | 2026-04-16 |
| Meadows Mobile Park | Elmore | 0.90ppm | 0.90ppm | Detected | 2026-01-06 |
| Island Village Mobile Home Park | Ada | 0.90ppm | 0.90ppm | Detected | 2026-03-24 |
| Blue Sage Subdivision | Elmore | 0.70ppm | 0.70ppm | Detected | 2026-01-20 |
| City of Middleton | Canyon | 0.60ppm | 0.60ppm | Detected | 2026-01-12 |
| Rustic Acres Mobile Home Park | Ada | 0.60ppm | ND | Detected | 2025-11-20 |
| Lakeys Cafe and Trailer Park | Canyon | 0.60ppm | 0.60ppm | Detected | 2026-02-09 |
| Christis Mobile Park | Canyon | 0.60ppm | 0.60ppm | Detected | 2026-01-14 |
| H and L Park | Canyon | 0.60ppm | 0.60ppm | Detected | 2026-02-09 |
| Garden City Water and Sewer System | Ada | 0.50ppm | ND | Detected | 2026-06-16 |
| Eagle Glen Homeowners Association Inc. | Ada | 0.50ppm | 0.30ppm | Detected | 2026-03-24 |
| Stanley Pond Inc. | Ada | 0.50ppm | 0.50ppm | Detected | 2026-02-26 |
| Vanal Heights Sweet Water | Canyon | 0.50ppm | 0.40ppm | Detected | 2025-12-29 |
| Pleasant View Manor | Canyon | 0.48ppm | 0.48ppm | Detected | 2026-05-20 |
| Shilo Ranch Estates | Boise | 0.40ppm | ND | Detected | 2026-05-11 |
| Evergreen Mobile Park | Canyon | 0.30ppm | 0.30ppm | Detected | 2026-01-14 |
| Castle Mountain Creeks Owners Association | Boise | 0.30ppm | ND | Detected | 2026-07-22 |
| Danskin Properties Association Inc. | Elmore | 0.30ppm | 0.30ppm | Detected | 2026-01-07 |
| Vanal Heights Well Association | Canyon | 0.21ppm | ND | Detected | 2026-01-12 |
| City of Notus | Canyon | 0.20ppm | 0.20ppm | Detected | 2026-04-22 |
| Somerset West Water Corp. | Canyon | 0.20ppm | ND | Detected | 2025-11-24 |
| Klugherz Water Corp. | Ada | 0.20ppm | 0.20ppm | Detected | 2026-06-22 |
| Country Club Subdivisions Water Association | Canyon | 0.20ppm | 0.20ppm | Detected | 2026-03-11 |
| Stecher Water Users Association | Canyon | 0.20ppm | 0.20ppm | Detected | 2026-06-16 |
| Lakeview Water Company 1 | Canyon | 0.17ppm | 0.14ppm | Detected | 2025-06-05 |
| Idaho City Water Department | Boise | 0.05ppm | 0.04ppm | Detected | 2025-11-19 |
Limits
- Federal limit (MCL)
- 10 mg/L (10.00ppm)
- Health goal (MCLG)
- 10.00ppm
Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome.EPA, quoted. For infants and pregnancy, read the agency text as written.
Removal methods in the reference list: reverse osmosis, anion exchange, distillation. A method name is not a product certification.
By city: Nitrate (as N) in Mountain Home drinking water, Nitrate (as N) in Mountain Home AFB drinking water, Nitrate (as N) in Nampa drinking water, Nitrate (as N) in Boise City drinking water, Nitrate (as N) in Garden City drinking water, Nitrate (as N) in Meridian drinking water, Nitrate (as N) in Glenns Ferry drinking water, Nitrate (as N) in Robie Creek drinking water, Nitrate (as N) in Wilder drinking water, Nitrate (as N) in Caldwell drinking water, Nitrate (as N) in Kuna drinking water, Nitrate (as N) in Eagle drinking water, Nitrate (as N) in Star drinking water, Nitrate (as N) in Middleton drinking water, Nitrate (as N) in Notus drinking water, Nitrate (as N) in Idaho City drinking water.
833 groundwater zones in the region have confident (grade A or B) estimates for Nitrate (as N). See well estimates by ZIP.
Numbers are the system's samples at its taps and wells, not yours. Lead and copper are 90th percentiles from sampled homes. Well pages are nearby-sample estimates. Health text restates EPA and DEQ. Methodology.