goMURra (Cross-border management plan for innovative and sustainable management of the border Mura and for improvement of flood risk management) – Optimisation of measures at the border Mura using innovative numerical simulations

The interruption of the sediment continuum and the channelisation of the river led to a strong morphological impairment and to a deepening of the river bed in the section of the Mur at the state border between Austria and Slovenia (border Mura), which resulted in ecological and technical problems. At the same time, the border Mura is embedded in Austria's second largest continuous alluvial forest and is connected to the Drava and the Danube downstream without a continuum interruption, so that this section has great ecological potential. In the basic water management concept for the Grenzmur from 2001, bank erosion was attributed an important role for the success of restoration measures; however, in a subsequent measure implemented, this only occurred to a limited extent, which reduced the general effectiveness of the measure. Within the framework of the EU Interreg SI-AT project goMURra, a new management plan with proposals for restoration measures is being developed, which are further developed and optimised with regard to their river morphological effects. This requires a numerical simulation of the hydrodynamics and morphodynamics and, in order to reconstruct the relevant processes such as bank erosion as a function of different types and variants of measures, corresponding development work on the numerical simulation tools. In order to design realistic measures for in-depth testing by means of numerical simulation, simplified tools for estimating space requirements are applied in advance. Finally, an adaptive model application should lead to optimised implementation variants of different types of measures, which serve as a basis for the implementation of effective restoration projects within the management plan.