The influence of climate and land-cover scenarios on dam management strategies in a high water pressure catchment in North-east Spain

The water management of Boadella-Darnius reservoir (NE Spain) has been analysed for the period 1971-2013 to understand the different strategies applied in the past. Streamflow has been projected under climate conditions included in the Third Report on Climate Change in Catalonia (TCCC) and under land-use change scenarios. We have simulated Darnius-Boadella reservoir inflow (2021-2050) using the Regional Hydro-Ecologic Simulation System (RHESsys) with two objectives: (i) to analyse the impact of climate and land-use changes on the water resources of the basin and (ii) to analyse the different plausible strategies of water management at mid-term period (2021-2050). Results reveal a clear negative trend in dam inflow (-34.7%) since it was built in 1971. The simulations obtained with RHESsys show a similar trend at mid-term (2021-2050) with -31.1% under climate and land-use change conditions. Considering the ecological minimum flow outlined by Catalan Water Agency (ACA) and the possible dam inflow decrease, different water management strategies are needed to mitigate the effects of the expected climate change.