Beschreibung:
The effects of the discharge of wastewater treatment plants (WWTP) on the status of rivers have most commonly been focused on water quality. A very limited number of works have characterised the ability of treatment plants to modify flow patterns in the receiving rivers. This paper presents a methodology for the assessment of the hydrologic alteration caused by WWTP discharges, which is later applied to the Manzanares River (Central Spain), allowing the quantification of the flow alteration generated by the 7 WWTP which give service to Madrid city (3.8 million inhabitants). Results of the analysis show: (1) the ability of the proposed methodology to characterise the modification of flow patterns due to WWTP discharges; (2) the importance of assessing such changes when evaluating the environmental impact of treatment plants; (3) the relevance of designing preventive and mitigation measures which maintain the ecological integrity of river ecosystems in the receiving channels