What does TMDL stand for?
A. A TMDL is a process under the federal Clean Water Act (CWA) which first requires states to identify streams, rivers, and lakes that have become impaired by pollutants such as sediment, metals, bacteria, or nutrients (phosphorus and nitrogen). While these materials are naturally occurring, the pollution comes from an excess amount going into our waters created by human land-use activities. There is a scientific process and analysis to determine if a waterbody’s beneficial use has been impaired by pollution. Beneficial uses include: health of cold water aquatic life (trout and the insects they feed on, which can be impaired by excess sediment), swimming as impaired by fecal bacteria from sources such as sewage wastewater, and drinking water as could be impaired from pollution. In Idaho, there are many surface waters that have been identified as impaired and formally listed as such under the CWA 303(d) list. A TMDL is a watershed plan to reduce the amount (load) of an identified pollut
