Development of an Explicit Water Level Pool Routing Method in Reservoirs

Abstract

Local regulations control the additional runoff produced by urbanization processes. Sustainable urban drainage systems can mitigate the issues associated with increased runoff by employing infiltration basins, detention ponds, wet ponds, and constructed wetlands. Traditionally, the Water Level Pool Routing Method, which relies on an implicit calculation scheme, has been used to calculate outflow hydrographs in reservoirs. In this research, an explicit scheme for the Water Level Pool Routing Method has been developed. The proposed model is applied to a case study where the reservoir has a surface area of 9.12 hectares. The influence of weir width and the discharge coefficient is also analyzed. Additionally, the variation in time step does not significantly affect the response of the proposed model, demonstrating its adequacy as a novel method. The proposed model is compared to the traditional method, yielding similar results in an analyzed ornamental reservoir (low percentage reduction in peak flow). However, a case study with experimental data reveals that the proposed model provides better accuracy than the traditional method. In addition, the proposed model is more efficient as it reduces computational time compared to the implicit scheme (conventional method). Finally, the proposed model is simplified for small watersheds by applying the rational method for computing an inflow hydrograph.