Tap and WellTreasure Valley water, from the public record

Gross Alpha in Treasure Valley drinking water

84 of 136 systems that tested for it in the last 36 months detected it; 4 are above the limit, elevated, or an aesthetic issue. Gross Alpha is a naturally radioactive element. Certified filters are in the list.

The 15 pCi/L MCL applies to gross alpha excluding radon and uranium. Lab results shown in Drinking Water Watch are often unadjusted, so a raw value above 15 where uranium is also present is not by itself a violation. Check the violations section.

SystemCounty36 mo maxLatestStatusLast sample
Sunlight TerraceCanyon56.3pCi/L39.3pCi/LNot detected2026-06-02
Desert View Estates Water Corp.Ada55.7pCi/L55.7pCi/LNot detected2025-02-26
Paradise Estates Water Corp.Ada46.4pCi/L41.0pCi/LElevated2026-06-29
Rich SubdivisionCanyon44.6pCi/L44.6pCi/LNot detected2025-08-13
M and M Mountain View Subdivision Em2Canyon40.6pCi/L20.1pCi/LDetected2026-08-06
Capitol Water Corp.Ada37.9pCi/L25.0pCi/LNot detected2026-07-14
Meridian Water DepartmentAda37.5pCi/L23.2pCi/LNot detected2026-07-29
Rivervine SubdivisionAda30.4pCi/L30.4pCi/LDetected2024-09-27
Stecher Mutual Water CompanyCanyon30.1pCi/L14.0pCi/LElevated2026-07-15
Veolia Water IdahoAda29.5pCi/L29.5pCi/LNot detected2026-07-28
West Meadows EstatesAda29.5pCi/L29.5pCi/LDetected2025-08-12
Riley Trailer ParkAda27.4pCi/L27.4pCi/LAbove limit2025-08-13
Gem State AcademyCanyon24.2pCi/L24.2pCi/LDetected2025-11-13
City of NampaCanyon22.4pCi/L11.1pCi/LDetected2026-05-13
Sunnyridge 3 Water Corp.Canyon21.4pCi/L9.90pCi/LDetected2025-12-16
Verde Hills Water Users Association Inc.Canyon20.9pCi/L20.9pCi/LDetected2025-04-22
Caldwell Housing AuthorityCanyon19.5pCi/L19.5pCi/LNot detected2025-06-16
City of CaldwellCanyon19.0pCi/L5.48pCi/LDetected2025-08-20
Par Estates Homeowners AssociationCanyon18.7pCi/L18.7pCi/LDetected2025-12-18
Sunnyridge Property OwnersCanyon18.5pCi/L18.5pCi/LDetected2025-09-23
Woodview Acres Property OwnersCanyon17.6pCi/LNDNot detected2025-12-11
Silver Spur SubdivisionCanyon17.4pCi/L17.4pCi/LDetected2025-05-20
City of KunaAda16.4pCi/L11.2pCi/LDetected2026-06-10
Indian VillageCanyon15.9pCi/L15.9pCi/LDetected2025-12-02
Covert Water Users AssociationCanyon14.8pCi/L14.8pCi/LDetected2025-10-20
Country Meadows SubdivisionCanyon14.6pCi/L14.6pCi/LNot detected2025-11-18
Clark Theurer Water AssociationCanyon14.5pCi/L14.5pCi/LElevated2025-06-06
Sunnyridge Subdivision 2Canyon14.0pCi/L14.0pCi/LDetected2025-12-16
City of Eagle (Eastern Zone)Ada13.5pCi/L13.5pCi/LNot detected2025-03-21
Belle Aire Acres 2Canyon13.3pCi/L11.5pCi/LDetected2025-09-23
Purple Sage CommunityCanyon13.0pCi/L13.0pCi/LDetected2024-02-06
Northridge Estates Water AssociationCanyon12.6pCi/L12.6pCi/LDetected2025-04-22
Lindenwood Water AssociationCanyon12.6pCi/L12.6pCi/LNot detected2025-06-18
Lakeridge Second SubdivisionCanyon12.5pCi/L3.12pCi/LNot detected2025-08-15
Shalimar SubdivisionCanyon12.4pCi/L12.4pCi/LDetected2025-07-21
Camelot Water Association Inc.Canyon12.4pCi/L12.4pCi/LDetected2025-11-24
Karcher Ranchette Water Corp.Canyon11.8pCi/L11.8pCi/LDetected2025-11-24
Skyline Water AssociationCanyon11.6pCi/L11.6pCi/LDetected2025-09-23
Rolling Hills Estates Water CompanyCanyon10.4pCi/LNDDetected2025-05-09
Eagle West Subdivision Water AssociationAda9.76pCi/L9.76pCi/LDetected2025-04-22
Sunnyridge I SubdivisionCanyon9.73pCi/L1.02pCi/LNot detected2025-10-20
Apache Heights Subdivision (2)Canyon9.71pCi/L9.71pCi/LDetected2025-12-02
Rustic Acres Mobile Home ParkAda9.58pCi/L9.58pCi/LNot detected2025-11-20
D and S Purple Sage RanchettesCanyon9.24pCi/LNDNot detected2025-05-02
IDOC Idaho State Correctional CenterAda8.53pCi/L8.53pCi/LDetected2025-08-19
Eagle MHCAda8.52pCi/L8.52pCi/LDetected2025-05-15
Arrowrock RanchAda8.20pCi/L4.35pCi/LDetected2025-12-04
Somerset West Water Corp.Canyon8.12pCi/L8.12pCi/LDetected2025-11-24
Westview Shervik SubdivisionCanyon7.24pCi/L7.24pCi/LDetected2025-07-21
Maverick Subdivision Lasher ConstructionCanyon7.19pCi/L1.70pCi/LNot detected2025-10-15
Shamrock Villa Water AssociationCanyon7.16pCi/L7.16pCi/LDetected2025-10-07
Locust SubdivisionCanyon6.97pCi/L2.28pCi/LNot detected2025-12-03
Flying H Trailer RanchAda6.62pCi/L6.62pCi/LDetected2025-04-08
Evans Water Corp.Ada6.59pCi/L3.09pCi/LDetected2025-03-04
Leisure Heights Homeowners AssociationCanyon6.44pCi/L6.44pCi/LDetected2025-11-17
Sierra Water Corp.Ada6.41pCi/L6.41pCi/LDetected2025-04-28
City of MelbaCanyon6.28pCi/L5.20pCi/LDetected2026-07-01
Wymosa Water Association Inc.Ada6.13pCi/L6.13pCi/LDetected2025-11-19
Twin Bridges SubdivisionCanyon5.89pCi/L5.89pCi/LNot detected2025-12-02
IDOC SBX ComplexAda5.37pCi/L5.37pCi/LNot detected2025-08-05
Terrace Water Corp. Inc.Ada5.23pCi/L5.23pCi/LNot detected2025-11-20
Hi View WaterAda5.19pCi/L5.19pCi/LDetected2025-06-18
Klugherz Water Corp.Ada4.97pCi/L4.97pCi/LDetected2026-06-22
El Rancho HeightsCanyon4.82pCi/L4.82pCi/LDetected2025-11-24
Anderson Circle Water Corp.Ada4.81pCi/L4.81pCi/LDetected2025-06-26
Willowbrook Estates Property OwnersAda4.43pCi/L4.43pCi/LNot detected2025-11-25
Scottys Mobile Home ParkAda4.41pCi/L4.41pCi/LDetected2025-04-22
Linda Vista Mobile Home ParkAda4.13pCi/L4.13pCi/LNot detected2025-04-08
Simplot Livestock Company GrandviewElmore4.08pCi/L4.08pCi/LDetected2026-08-11
Hamilton PlaceElmore4.05pCi/L4.05pCi/LDetected2025-11-11
Valley View WaterCanyon4.03pCi/L4.03pCi/LNot detected2025-02-12
Vanal Heights Sweet WaterCanyon3.95pCi/L3.95pCi/LNot detected2025-12-29
Trinity Estates Water Users AssociationElmore3.86pCi/LNDDetected2026-06-17
Country Club Subdivisions Water AssociationCanyon3.81pCi/L3.81pCi/LDetected2025-06-16
Dahl SubdivisionCanyon3.80pCi/L3.80pCi/LDetected2025-12-11
Stecher Water Users AssociationCanyon3.74pCi/L3.74pCi/LNot detected2024-07-17
Malad and Hilton Water Company Inc.Ada3.66pCi/L3.66pCi/LDetected2025-06-26
Lakeview Hills Water Users AssociationCanyon3.59pCi/L3.59pCi/LDetected2025-12-02
Horseshu Vue Ranch SubdivisionBoise3.13pCi/L3.13pCi/LDetected2025-12-16
Oakleaf SubdivisionElmore0.00pCi/L0.00pCi/LNot detected2025-11-11
Danskin Properties Association Inc.Elmore0.00pCi/L0.00pCi/LNot detected2025-10-29
Forrey HeightsAda0.00pCi/L0.00pCi/LNot detected2025-11-13
Amy Trailer ParkAda0.00pCi/L0.00pCi/LNot detected2025-10-22
Boise Holcomb Water Users Assoc. Inc.Boise0.00pCi/L0.00pCi/LNot detected2025-10-29

Limits

Federal limit (MCL)
15.0pCi/L
Health goal (MCLG)
0.00pCi/L
Some people who drink water containing alpha emitters in excess of the MCL over many years may have an increased risk of getting cancer.EPA, quoted.

Removal methods in the reference list: reverse osmosis, ion-exchange softener. A method name is not a product certification.

By city: Gross Alpha in Kuna drinking water, Gross Alpha in Boise City drinking water, Gross Alpha in Meridian drinking water, Gross Alpha in Eagle drinking water, Gross Alpha in Garden City drinking water, Gross Alpha in Nampa drinking water, Gross Alpha in Caldwell drinking water, Gross Alpha in Mountain Home drinking water.

Not enough groundwater samples in the region to estimate Gross Alpha in private wells. A lab test is the only way to know.

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.