%0 Journal Article %T A New Model for Simulating TSS Washoff in Urban Areas %A E. Crobeddu %A S. Bennis %J Applied and Environmental Soil Science %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/318765 %X This paper presents the formulation and validation of the conceptual Runoff Quality Simulation Model (RQSM) that was developed to simulate the erosion and transport of solid particles in urban areas. The RQSM assumes that solid particle accumulation on pervious and impervious areas is infinite. The RQSM simulates soil erosion using rainfall kinetic energy and solid particle transport with linear system theory. A sensitivity analysis was conducted on the RQSM to show the influence of each parameter on the simulated load. Total suspended solid (TSS) loads monitored at the outlet of the borough of Verdun in Canada and at three catchment outlets of the City of Champaign in the United States were used to validate the RQSM. TSS loads simulated by the RQSM were compared to measured loads and to loads simulated by the Rating Curve model and the Exponential model of the SWMM software. The simulation performance of the RQSM was comparable to the Exponential and Rating Curve models. 1. Introduction During high-intensity rainfall events, the discharge of untreated storm water and wastewater occurs into receiving waters when the capacity of combined sewer systems (CSSs) is exceeded. The combined sewer overflow events (CSOs) generate high concentrations of microbial pathogens, biochemical oxygen demand, total suspended solids, and other pollutants into receiving waters [1]. Minimizing the impact of watercourse pollution through intercepting the maximum amount of pollutant particles is of increasing concern to municipalities. Knowledge of the wet weather pollutograph seems essential in order to maximize sewer network pollutant interception in real-time management. However, it is difficult to predict the pollutograph associated with each pollutant. Total suspended solid (TSS) load is considered the main vector of runoff water pollution in urban areas [2, 3]. Consequently, a good estimation of water pollution can be given knowing the concentration of suspended particles in storm water [4]. The cycle of solid particles in an urban area is a complex process that involves solid particle buildup in the catchment during dry weather periods followed by solid particle washoff during wet weather periods. The most frequently used buildup models are asymptotic, most often derived from the Alley and Smith [5] exponential model used in the Storm Water Management Model (SWMM) software, but may also be linear [6]. The process of soil washoff in urban areas is often represented with conceptual approaches. The simplest conceptual model is the Rating Curve model [7, 8] that links %U http://www.hindawi.com/journals/aess/2011/318765/