title: Integrated modelling to assess long-term water supply capacity of a meso-scale Mediterranean catchment.
abstract: Assessing water supply capacity is crucial to meet stakeholders' needs, notably in the Mediterranean region. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500 km(2), France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need first to understand the processes controlling the evolution of water resources and demands in the past to latter evaluate future water supply capacity and anticipate the tensions users could be confronted to in the future. A modelling framework is proposed at a 10-day time step to assess whether water resources have been able to meet water demands over the last 50 years. Water supply was evaluated using hydrological modelling and a dam management model. Water demand dynamics were estimated for the domestic and agricultural sectors. A water supply capacity index is computed to assess the extent and the frequency to which water demand has been satisfied at the sub-basin scale. Simulated runoff dynamics were in good agreement with observations over the calibration and validation periods. Domestic water demand has increased considerably since the 1980s and is characterized by a seasonal peak in summer. Agricultural demand has increased in the downstream sub-basins and decreased upstream where irrigated areas have decreased. As a result, although most water demands were satisfied between 1961 and 1980, irrigation requirements in summer have sometimes not been satisfied since the 1980s. This work is the first step toward evaluating possible future changes in water allocation capacity in the catchment, using future climate change, dam management and water use scenarios.
authors.affiliation: UM2-UMR HydroSciences Montpellier, Place E. Bataillon, 34395 Montpellier Cedex 5, France. lila.collet@um2.fr
authors.forename: Lila
authors.initials: L
authors.lastname: Collet
authors.forename: Denis
authors.initials: D
authors.lastname: Ruelland
authors.forename: Valérie
authors.initials: V
authors.lastname: Borrell-Estupina
authors.forename: Alain
authors.initials: A
authors.lastname: Dezetter
authors.forename: Eric
authors.initials: E
authors.lastname: Servat
mesh_terms: D000383:Agriculture / Q000379:methods* / Q000706:statistics & numerical data; D057231:Climate Change; D005544:Forecasting; D005602:France; D008962:Models, Theoretical; D045483:Rivers; D012621:Seasons; D058438:Water Cycle; D014872:Water Movements; D014881:Water Supply
keywords: AWD; Aggregation Function; Agricultural Water Demand; Climate variability; DWD; Domestic Water Demand; F(agg); Integrated modelling; NSE; NSE(lf); Nash–Sutcliffe efficiency criteria; Nash–Sutcliffe efficiency criteria during low-flows; River Hérault; VE; VE(m); Volume Error; WD; WRA; WSCI; Water Demand; Water Resources Availability; Water Supply Capacity Index; Water demand; Water resources; Water supply assessment; mean Volume Error