Assessing the effects of land cover change in runoff processes with RHESSys: a case study in the Waterford River Watershed, Newfoundland and Labrador, Canada

Abstract

Evaluating the current state of hydrologic processes in urban and semi-urban areas is an essential part of ensuring the sustainable management of water and preventing emergencies of extreme events. This study evaluated the effects of land use and land cover (LULC) change on runoff processes in the Waterford River Watershed (WRW), located in the eastern part of the province of Newfoundland and Labrador (NL), Canada. The Regional Hydro – Ecological Simulation System (RHESSys), a GIS-based hydro-ecological model, was used in a new urbanistic approach to simulate the effects of increasing impervious land as well as reducing urban green areas. The increase in hypothetical peak flows had a direct relationship with the reduction of pervious areas in the watershed. The most sizeable flow increases were observed in the periods of April to May and October to December. This study emphasizes the importance of using a prominent network of green and pervious structures or water retention areas when allocation for residential and commercial land increase.