Starting from organic ...

Starting from organic carbons, DO and E.coli, and nutrients (N, P) should be considered further in improvement processes

For the water quality parameters, the answer (comments) from Bruno Peeters seems to be a good answer. BOD, DO and E.coli have been basic parameters for the river water quality especially with deteriorated water quality. After water quality improvement, e.g. BOD

For the indicators to control pollutant discharge, point sources especially from municipal wastewater as well as industry sources should be targeted. Pollutant discharge per capita (PDC) would be an important parameter for management and planning municipal wastewater pollutant discharges.