Removal of antimicrobial resistance (AMR) in surface flow constructed wetlands with different upstream treatment flowsheets
Constructed wetlands (CWs) have been widely adopted for secondary/tertiary treatment as the final safeguard of natural waters. Among various types of CWs, surface flow constructed wetlands (SFCWs) resemble natural wetlands most closely and feature designs such as wet meadows and marshes. However, their effectiveness in removing microbial micropollutants, specifically antimicrobial resistance (AMR), has not been well studied. Moreover, we hypothesize that the iron residues from upstream chemical dosing for phosphorus removal could initiate excessive reactive oxygen species (ROS) production in the rhizosphere area and significantly benefit the removal of AMR. This study aims to evaluate the long-term performance of AMR removal in applied SFCWs and assess the impact of different upstream treatment flowsheets. The experimental sites include one secondary treatment SFCW (~1.4 ha) from Wales and two tertiary treatment SFCWs (~1 ha) from England. The discharged water quality has met the discharge limits, and the AMR measurement results will be presented at the conference.