First Flush Stormwater Runoff in Urban Catchments: A Bibliometric and Comprehensive Review

• Published in: Hydrology 2022-04, Vol.9 (4), p.63
• Main Authors: Maniquiz-Redillas, Marla, Robles, Miguel Enrico, Cruz, Gil, Reyes, Nash Jett, Kim, Lee-Hyung
• Format: Article
• Language: English
• Subjects: Best management practices; Bibliometrics; Catchment area; Catchments; Climatic conditions; comprehensive review; Contingency; diffuse pollution; Environmental conditions; Environmental monitoring; event mean concentration; first flush; Geographical distribution; Geographical locations; Hydrology; Keywords; Land use; mass first flush; Nonpoint source pollution; Pollutants; Pollution control; Pollution monitoring; Pollution sources; Rain; Rainfall; River networks; Runoff; Storm runoff; Stormwater; Stormwater management; Stormwater runoff; Trends; Urban areas; Urban catchments; Urban runoff; Urban watersheds; Water pollution; Water quality
• ISSN: 2306-5338; 2306-5338
• DOI: 10.3390/hydrology9040063

First flush is a phenomenon in stormwater runoff that has been considered a topic of great interest in the field of nonpoint source pollution. Despite several attempts to define the first flush quantitively, the specified characteristics of the phenomenon vary among sources. To address these uncertainties, a bibliometric and comprehensive review on published articles related to first flush was conducted. A corpus of 403 research articles was obtained from the Scopus database, which was then parsed using the CorText Manager for the bibliometric analysis. The study examined quantitative definitions of first flush from various sources; climate and topographic characteristics of monitoring and experimental sites where the studies on first flush were performed; the sample collection methods applied; the first flush values obtained on the studies and how it influenced the nonpoint source pollution in urban watersheds. A network map, two contingency matrices, and a Sankey diagram were created to visualize the relationship of significant keywords related to first flush, as well as their co-occurrences with journals, countries, and years. It was found that the strength of the first flush effect could vary depending on the geographical location of the site, climatic conditions, and the pollutants being analyzed. Therefore, initial rainfall monitoring, runoff sampling, and water quality testing were seen as critical steps in characterizing the first flush in urban catchments. Furthermore, the characterization of first flush was found to be significant to the selection of best management practices and design of low-impact development (LID) technologies for stormwater runoff management and nonpoint source pollution control.