Loopholes in the current reclaimed water quality standards for clogging control during aquifer storage and recovery in China

This article presents a perspective on the current reclaimed water quality standards for clogging control during aquifer storage and recovery (ASR) in China. Water reuse and ASR in China are reviewed, and we examine how clogging contributes to the failures of ASR. We identify loopholes in current standards for clogging control. The threshold values of suspended solids and turbidity in these standards are effective for the prevention of clogging triggered by inorganic mineral suspended particles in regular recharge water sources (e.g., rainfall and floodwater). However, these threshold values are not low enough to prevent clogging when secondary effluent from wastewater treatment plants containing organic flocs of active sludge is introduced. Therefore, revision of current standards for clogging control is urgently needed.