Impaired Waters Rule (IWR) Stations

Statewide coverage of sampling locations (stations) primarily from WIN, STORET, SBIO, USGS & Legacy STORET providing data for the IWR Run 67 database. All available historic data are included in the database, therefore some stations may not contain any data used in current assessments. A station can only be used for IWR assessment purposes if it represents ambient water quality of surface water and the station can be definitively tied to one of the ~6,700 water bodies which we assess. A station will not be included in this coverage if it samples wastewater effluent, groundwater, is a rain gauge, etc.