First flush in a combined sewer system

Trends in long daily rainfall series of Lombardia (northern Italy) affecting urban stormwater control

“…These rainfall events are proper for this analysis also because the precipitation height of both these storms is equal to the corresponding daily precipitation. Experimental rainfall data, flow rates and concentrations of some pollutant parameters at the outlet of the sewer system are presented in Barco et al (2008). Numerical simulation of the catchment-sewer network was carried out using US EPA Storm Water Management Model.…”

Assessing the water quality benefits of green infrastructure stormwater control measures.

“…According to the National Stormwater Quality Database, first flush concentrations of TSS, COD, TDS, total copper, total lead, total zinc and TKN are significantly higher than the composite sample collected during the entire rain event (Maestre and Pitt 2005). It has also been considered that GI control and BMPs focusing on treating the first flush runoff will be a more economical approach for reducing pollutants from the stormwater (Barco et al 2008).…”

Gross solids from combined sewers in dry weather and storms, elucidating production, storage and social factors

“…Thus deposition is more likely in upstream reaches (Staufer, 2011). This behaviour is also influenced by bed slope (although some authors report no mean daily storage in steep upstream catchments (Barco et al, 2008)), the buoyancy of sewage solids and duration of the pulse. The typical diurnal dry weather flow profile will only be observed downstream after convolution of numerous flushing events over the catchment.…”