Stormwater discharge: An overlooked source of disinfection byproduct precursors

Wenyuan Yang; Chao Fang; Tom Bond; Xinmiao Luan; Rong Xiao; Zuxin Xu; Wenhai Chu

doi:10.1016/j.jhazmat.2023.132720

Stormwater discharge: An overlooked source of disinfection byproduct precursors

J Hazard Mater. 2024 Jan 5:461:132720. doi: 10.1016/j.jhazmat.2023.132720. Epub 2023 Oct 5.

Authors

Wenyuan Yang¹, Chao Fang¹, Tom Bond², Xinmiao Luan¹, Rong Xiao¹, Zuxin Xu¹, Wenhai Chu³

Affiliations

¹ State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
² School of Sustainability, Civil and Environmental Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK.
³ State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China. Electronic address: feedwater@126.com.

PMID: 37813036
DOI: 10.1016/j.jhazmat.2023.132720

Abstract

Discharge from the stormwater system is as an important pathway for contaminant transport, impacting the quantity and characteristics of dissolved organic matter (DOM) in surface water, and thus the formation of disinfection byproducts (DBPs) during downstream drinking water disinfection. In this study, DOM in stormwater pipes was characterized by size-exclusion chromatography, and the formation of 27 DBPs and halogen-specific total organic halogen (TOX) following chlorination was investigated. Overall, DOM in stormwater pipes was characterized by low molecular weight compounds and microbial-derived organics. Total DBP concentrations in chlorinated stormwaters were ∼1-15 times higher than in chlorinated surface waters. DBPs formed in stormwaters were dominated by trihalomethanes and haloacetic acids. Moreover, the DBP-associated toxicity of chlorinated stormwaters was ∼1-38 times higher than in chlorinated surface waters, and mainly due to the presence of large amount of haloacetaldehydes and haloacetonitriles. Sampling during a rainfall event suggested that stormwater discharge significantly increased DBP precursors in the surface water. The high formation and estimated toxicity of DBPs in stormwater discharge indicates this is an overlooked source of DBP precursors, posing a threat to the aquatic environment and potentially drinking water quality.

Keywords: DBP precursors; DOM characteristics; Disinfection byproducts; Stormwater pipes; Total organic halogen.