Tap and WellTreasure Valley water, from the public record

Manganese in Treasure Valley drinking water

8 of 15 systems that tested for it in the last 36 months detected it; 5 are above the limit, elevated, or an aesthetic issue. Manganese is a secondary, aesthetic parameter. Certified filters are in the list.

Often occurs with iron in valley wells. Certified manganese claims are uncommon.

SystemCounty36 mo maxLatestStatusLast sample
Veolia Water IdahoAda537.0ppb432.0ppbAesthetic issue2026-08-25
Garden City Water and Sewer SystemAda247.0ppb233.0ppbAesthetic issue2026-01-15
Hillsdale Estates Homeowners AssociationAda212.0ppb212.0ppbAesthetic issue2025-11-06
Terrace Lakes Water CompanyBoise127.0ppb127.0ppbAesthetic issue2025-08-20
Rolling Hills Estates Water CompanyCanyon75.0ppbNDAesthetic issue2025-03-24
Klugherz Water Corp.Ada45.0ppb45.0ppbDetected2025-03-24
Star Sewer and Water District Water SystemAda31.0ppb31.0ppbDetected2023-12-06
Boise Holcomb Water Users Assoc. Inc.Boise19.0ppb19.0ppbDetected2025-04-02

Limits

Secondary (aesthetic) standard
0.05 mg/L (50.0ppb)
Health guideline
300.0ppb (EPA lifetime health advisory)
Manganese is a secondary standard at 0.05 mg/L for black staining and taste. EPA has a lifetime health advisory of 0.3 mg/L; infants are more sensitive.Agency language as recorded in the contaminant reference.

Removal methods in the reference list: oxidation filtration, manganese greensand, ion-exchange softener. A method name is not a product certification.

By city: Manganese in Boise City drinking water, Manganese in Garden City drinking water, Manganese in Meridian drinking water, Manganese in Star drinking water.

704 groundwater zones in the region have confident (grade A or B) estimates for Manganese. 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.