Hydrol. Earth Syst. Sci., 24, 249–267, 2020 https://doi.org/10.5194/hess-24-249-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. A multi-environmental tracer study to determine groundwater residence times and recharge in a structurally complex multi-aquifer system Cornelia Wilske1,2, Axel Suckow2, Ulf Mallast1, Christiane Meier3, Silke Merchel4, Broder Merkel5, Stefan Pavetich4,6, Tino Rödiger7, Georg Rugel4, Agnes Sachse7, Stephan M. Weise1, and Christian Siebert1 1Department of Catchment Hydrology, Helmholtz Centre for Environmental Research, Halle (Saale), 06120, Germany 2CSIRO Land and Water, Urrbrae, South Australia, 5064, Australia 3Umweltbundesamt (UBA), Dessau-Roßlau, 06844, Germany 4Helmholtz-Zentrum Dresden-Rossendorf, Dresden, 01328, Germany 5Technische Universität Bergakademie Freiberg, 09599, Germany 6Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2609, Australia 7Department of Computational Hydrosystems, Helmholtz Centre for Environmental Research, Leipzig, 04318, Germany Correspondence: Christian Siebert (
[email protected]) Received: 30 August 2019 – Discussion started: 9 September 2019 Revised: 18 November 2019 – Accepted: 11 December 2019 – Published: 16 January 2020 Abstract. Despite being the main drinking water resource the groundwater were further indications of infiltration dur- for over 5 million people, the water balance of the Eastern ing the last 30 years. The combination of multiple environ- Mountain Aquifer system on the western side of the Dead mental tracers and lumped parameter modelling helped to Sea is poorly understood. The regional aquifer consists of understand the groundwater age distribution and to estimate fractured and karstified limestone – aquifers of Cretaceous recharge despite scarce data in this very complex hydro- age, and it can be separated into a Cenomanian aquifer (upper geological setting.