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Stormwater runoff from a homogeneous residential area in Windsor, Ontario, was studied over a 1 year period of time. Hourly grab samples were taken and analyzed for 21 constituents. Seasonal and annual concentration data are reported along with the most significant correlations among constituent concentrations. Other influences on runoff quality are discussed. Rainfall for all 25 storms was measured, and discharge was measured for 13 storms. The discharge data and rainfall data were used to generate runoff hydrographs for 9 storms without measured hydrographs. The hourly discharges and concentrations were used to calculate loadings on an annual and seasonal basis. The loadings' variation on an hourly basis is listed. The results of an empirical analysis of the average annual loadings contained in percentage amounts of annual runoff are reported. Significant correlation was found between the preceding two variables for all constituents whose loads were calculated. A comparison is made between annual loadings of stormwater runoff and raw sewage for biochemical oxygen demand and total suspended solids and orthophosphates.

Very few urban storm water runoff studies have produced quantitative pollutional loadings and those that have cover a narrow range of parameters. This study produced qualitative values ranges of values and mean values on a seasonal and annual basis for nineteen physical chemical and bacteriological parameters. In addition the rainfall and runoff quantities were recorded and thence the quantities of the pollutants in pounds per acre per season were determined. Although the concentration of a pollutant at a given point in time is meaningful the total quantity produced is in many cases more meaningful when total pollutional loads reaching a receiving water are needed. Such information has been available for some time with respect to treatment plant and industrial waste effluents. However with respect to urban storm runoff the information is very sketchy. It is in answer to such a need that this research was conducted.