BasinMaker 3.0: A GIS toolbox for distributed watershed delineation of complex lake-river routing networks.

Hydrological modelling efforts tend to ignore the impacts of lakes or explicitly simulate the behavior of only the largest lakes in a watershed as deriving information required to explicitly represent thousands of lakes is difficult. We introduce an open-source GIS toolbox (BasinMaker) that can efficiently build vector-based hydrological routing networks including an arbitrary number of rivers and lakes, with attributes (e.g., network topology, subbasin and lake geometry, channel characteristics) that provide the inputs required for hydrological routing models. BasinMaker functionality is demonstrated to build two high-resolution vector-based lake-river routing products each defining a collection of routing networks across large regions: the North American Lake-River Routing and Ontario Lake-River Routing Products. Each includes all lakes over 10 ha identified in the HydroLAKES dataset. BasinMaker is unique in terms of lake representation and is especially helpful for modelers who need to explicitly represent numerous lakes in their watershed simulation models.