An Investigation into the Chemical and Biological Effects of Pollution in the River Tolka

Abstract

Physico-chemical and biological sampling show that the River Tolka is affected by organic pollution over most of its length. Domestic sewage is the major contaminant. A distinct zonation of the river is noted as certain polluted areas are succeeded by downstream recovery zones. Many of the effluents and tributaries are investigated. Oxygen depletion and excessive ammonia concentrations are the factors most likely to have caused the observed faunal changes.