Exploring urban runoff complexity: road-deposited sediment wash-off mechanisms and dynamics of constraints

• DOI: 10.2166/hydro.2024.022
• Publication Date: 2024-05-22T11:52:27Z
• Authors: Muhammad Faisal; Zai-Jin You; Muhammad Bilal Id...; Shoaib Ali; Noman Ali Buttar
• Keywords: urban runoff; Environmental Engineering; source; Urban Hydrology; Hydrological Modeling; Urban Stormwater Management and Sustainable Drainage Systems; 0207 environmental engineering; Urban Flooding; Information technology; 02 engineering and technology; Environmental technology. Sanitary engineering; Environmental science; Global Flood Risk Assessment and Management; Biology; TD1-1066; Urban Stormwater Management; Global and Planetary Change; Global Analysis of Ecosystem Services and Land Use; Ecology; Sustainable Drainage Systems; FOS: Environmental engineering; Hydrology (agriculture); Geology; Geomorphology; FOS: Earth and related environmental sciences; wash-off; T58.5-58.64; Surface runoff; particle grain size; Geotechnical engineering; FOS: Biological sciences; buildup; transport; Environmental Science; Physical Sciences; Sediment

ABSTRACT

To accurately figure out how much pollution comes from urban surface runoff and take steps to protect receiving water, we needed to fully understand how road-deposited sediments (RDS) wash off. Our research indicates that particles smaller than 100 μm imparted 59–73% of the wash-off load. Two instances of natural rainfall reduced the aggregate RDS mass by approximately 27–36%. On days without rain, the RDS particle shrank in size, but it became heavier after a downpour. The results showed that the source restricted the tiny particles washed off of RDS, while transport generally restricted the heavier particles washed off. We used 39 artificial rainfall events with different particle sizes to confirm our results on RDS wash-off. When compared to the heavier particles, tiny particles have a greater wash-off percentage, and when it comes to describing the wash-off mechanism, Fw values offer an inventive and insightful assessment. It has been assessed that tiny particles were source-restricted and this mechanism occurred during the initial stage, but heavier particles were transport-restricted and it occurred during the late stage.