Year: 2010
Type: conference-paper
Abstract: Stormwater quality is receiving increased scrutiny to reduce ecological degradation of urban \nwaterways. In order to predict the fate of key contaminants in stormwater runoff, a model applicable to \nthe local conditions in Christchurch is necessary. We are developing a model to estimate contaminant \nsources, transport and fate, which will help decision makers ascertain best structural and management \npractices to reduce contaminant loading to urban waterways. Necessary input parameters include \ncoefficients for contaminant build-up and wash-off functions that describe the deposition during \nantecedent dry days and dislodgement during a rain event. To derive these parameters, we constructed \nthin boards of different street materials (e.g. asphalt, concrete), which were exposed at various \nlocations within a University of Canterbury carpark over a nine day period before being placed under a \nrainfall simulator to collect surface runoff. Our experimental results showed that asphalt retains more \ncontaminant particles compared to concrete surfaces. Spatial variability of contaminant distribution \nwithin the carpark was high. First flush TSS wash-off concentrations from concrete boards, for \nexample, ranged from 63 to 164 mg/L. Similar variability was also observed for copper and lead \nconcentrations from both concrete and asphalt boards. Variation was attributed to factors such as the \nnumber and type of vehicles parking over the boards. The application of this experimental data to \nparameterize our initial model resulted in predictions that seemed realistic and are comparable to \nmeasured TSS and copper concentrations in stormwater.
Language: English
Subfield: Environmental Engineering
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W91609175