A simple model of flow-rate attenuation in sewer systems. Application to urban stormwater source control

- A top-down approach is proposed to model “soft” city-scale stormwater solutions.
- An empirical model of flow-rate attenuation in the sewer system is developed.
- The attenuation model is used to test the effectiveness of source control regulations.
- Which regulation is the most effective depends on the position in the catchment.
- Simple models can improve stormwater management strategies at the city-scale.

SummaryIn urban stormwater management, “soft” solutions are being widely applied, including stormwater source control. However, no specific resource-effective model is available to assess their effects at the city-scale. As a consequence, source control regulations are often based on simplistic hydrologic assumptions. In this paper, we apply a top-down modeling approach to this problem, and we develop a simple model of flow-rate attenuation in the sewer system, using a numerical empirical approach. Then, we apply the model to source control regulations, assessing which type of regulation is more effective depending on relative positions in a catchment. We show that a model requiring only two types of information about a catchment (concentration time and pluviometry) can provide relevant information on source control effectiveness. This information could be helpful, for example, to define a stormwater zoning.