A REVIEW OF THE EFFECTS OF SEWER LEAKAGE ON GROUNDWATER QUALITY

In: Water and environment journal, Band 17, Heft 1, S. 34-39

Abstract

ABSTRACTExfiltration (of sewage into the ground from faults in ageing sewerage networks) has been recognised for many years but has never been quantified. It was considered that this leakage did not pose a groundwater‐contamination threat because it was assumed that pathogens in sewage would either die off or be attenuated before reaching the groundwater level.This paper identifies why sewers have faults that could allow sewage exfiltration where the sewer is above a groundwater resource. Because of a lack of UK data on sewage exfiltration, research work in Germany is discussed and analogies are made between the sewerage networks of the two countries.Until recently, it has not been possible to positively identify sewage contamination of groundwater because of other pollutants and potential sources within an urban environment. The development of sewage‐fingerprinting techniques has overcome these difficulties and provides conclusive evidence of sewage contamination of shallow and deep groundwater resources in researched areas. Studies of groundwater recharge and total solute loadings allow quantification of sewage exfiltration reaching the groundwater within the Midlands conurbation. The paper concludes that urban aquifers are potentially more vulnerable to microbiological contamination from leaking sewers than has previously been assumed.