First Flush of Organics in Highway Runoff

Abstract

Stormwaters from three highway sites were monitored over two wet seasons for organics, Chemical oxygen demand, oil and grease and polyaromatic hydrocarbons (PAHs) were measured. The sites exhibited a first flush in most cases for most parameters. The mass first flush ratio (the ratio of the normalized transported mass of pollutant to the normalized runoff volume) generally was above 1.8 for the first 25% of the runoff volume, and in some cases as high as 2.8. Dissolved PAHs were generally at or below detection limits. Mass emission rates for particulate PAHs are reported. The results suggest that best management practices (BMPs) that address the initial runoff can have greater effectiveness than other types of BMPs.

Road sediment, an underutilized material in environmental science research: A review of perspectives on United States studies with international context

“…This notion of "first flush", presented by Sansalone's research group, has also been extensively applied internationally in stormwater management. Some researchers found this effect on highways (e.g., Gupta and Saul, 1996;Sansalone and Buchberger, 1997b;Lau et al, 2002;Ma et al, 2002), whereas others did not (Barrett et al, 1998). Li et al (2005) found that approximately 40% of road sediment particles were mobilized with the first 20% of water volume from runoff.…”

“…Retention ponds, including bioretention systems, and permeable pavements have also led to a reduction of stormwater runoff parameters such as total suspended solids (TSS) (e.g., Ahiablame et al, 2012 and the references therein), which would include road sediment pollution particles and thus help protect aquatic systems. This area has been well investigated (e.g., Gupta and Saul, 1996;Sansalone and Buchberger, 1997b;Lau et al, 2002;Ma et al, 2002), and Li et al (2006) recommended that capturing the first 20% of runoff, by volume, would potentially remove 40% of the total particulate load (from calculated particle mass). This would remove a majority of the metals investigated, and thus lead to reduced deposition in stormwater.…”

A new modeling approach for estimating first flush metal mass loading

“…One of these was first flush (FF) characterization, carried out jointly by the Department of Civil and Environmental Engineering at the University of California, Davis (UCD) and Los Angeles (UCLA) campuses. The FF characterization study has been ongoing since 1998 and several aspects of FF characterization have been published in Ma et al (2002); Lau et al (2002); Kayhanian et al (2002).…”

Mass Loading of First Flush Pollutants with Treatment Strategy Simulations

“…Major issues examined include water quality and litter characteristics, correlations among contaminants, mass emission rates, a meaningful definition of the first flush phenomenon, first flush of organics, pollutant buildup and wash-off models, sampling strategies, particle size distribution, and toxicity. Some aspects of these research topics have been presented at national conferences and others have been submitted to or are published in peer-reviewed journals (7,10,(15)(16)(17)(18)(19)(20). The focus of this study is to perform various treatment simulations to demonstrate the benefits associated with treating the largest possible fraction of early runoff.…”