Impact of Leaky Sewers on Groundwater Quality

摘要

Wastewater from defect sewers can affect,groundwater quality.An assessment of this environmental impact for a city of 50-000 inhabitants(Rastatt,SW Germany)was done using marker species distributions,condition monitoring of the sewer network,lab-scale analogy experiments,and specifically instrumented in-situ test sites near defect sewers.The studies revealed elevated concentrations of iodated X-ray contrast media(up to 360 ng/L amidotrizoic acid)and boron concentrations in the urban groundwater which are directly related to leaky sewers.Other common Pharmaceuticals could not be detected in the groundwater.Observation wells were installed based on the information from a sewer defect database.These wells focusing on specific sewer leakages show significant changes in groundwater quality parameters.