Analytical probabilistic models for urban stormwater erosion potential

Analytical probabilistic models for urban drainage systems analysis have been developed at the University of Toronto since 1978. Towards the prediction of the erosion potential of stormwater, a new set of analytical probabilistic models is developed. The marginal probability distributions for peak channel velocity and the duration of a storm that the critical channel velocity is exceeded, termed exceedance duration are computed using derived probability distribution theory. Relatively close agreement exists between the derived marginal probability distributions for exceedance duration and continuous SWMM simulations at low return periods. It is these events of lower magnitude and higher frequency that are the most significant from an erosion standpoint.; Erosion potential is functionally dependent upon both exceedance duration and peak velocity and through future research effort, their joint probability density function may be a useful tool for screening or planning level analysis of an urban watershed.