Open River Network and Hydropower Cascade Modelling: A Python Framework for Integrated Hydrological Modelling and Simulation of Regulation Dynamics

We present Open River Network and Hydropower Cascade Modelling, a Python-based framework implemented in Jupyter Notebooks for integrated analysis and simulation of hydrological dynamics within river networks and hydropower dam cascades. The river network model supports data input from gridded datasets and time series observations for lumped and distributed hydrological modelling to simulate river discharges across subbasins in the river basin. A lake routing routine based on a modified Puls method has been incorporated, allowing integration of lake bathymetry and stage-discharge relationships. River routing employs kinematic wave routing based on 1D Saint-Venant equations to route discharges between river reaches. Calibration routines are embedded within the framework, supporting simple global shuffled optimisation algorithms and evolutionary algorithms. Building on the river network model, the hydropower cascade model includes two submodules: (i) a river network analysis module that computes the dynamic degree of regulation by hydropower dams, resulting downstream inflow alteration, and local degree of regulation introduced by each dam in the cascade; and (ii) an operational cascade module that implements user-defined reservoir regulation rules for long-term scheduling and short-term operational flexibility of both storage and run-of-river hydropower cascades, with a lag function to preserve the hydraulic connection between dams. This modelling framework provides a comprehensive hydrological analysis of heavily regulated river basins with multiple dams. Furthermore, it supports the simulation of operational and regulation dynamics across regulated hydropower cascades within river networks. This work has been conducted as part of the Interreg Aurora’s RE-HYDRO project.