Final Report Summary - RESCUE (River flood Embankments Subject to Climate change: Understanding Effects of future floods and novel ‘low-carbon’ adaptation measures)
Adaptation measures to address flood risk are a priority at European level. Flood defence embankments are and will remain the major asset in a flood defence system and they are therefore one of the major focus of flood risk management agencies. Key steps in the adaption process are
i) Assessing hazard of embankment failure
ii) Identifying adaptation options.
Hydro-mechanical models for the stability flood river embankments subject to flood are traditionally based on the assumptions of steady-state through-flow and zero pore-pressures above the phreatic surface, i.e. negative capillary pressures (suction) are ignored. RESCUE aims to introduce a stepchange in the approach to the assessment of embankment stability by considering more realistic transient flow conditions establishing upon a flood and taking into account the effects of suction on the hydro-mechanical response of the embankment. This allows for flood duration, antecedent flood, and antecedent precipitation incident to the embankment to be taken into account.
The aim of the RESCUE project is to develop an approach to assess the impact of climate-induced floods on stability of existing river flood embankments, at both local and regional scale, and to explore low-carbon remedial adaptation measures. The approach includes strategies for geotechnical characterisation assisted by field monitoring, real-time monitoring to support emergency management, and ‘accessible’ tools for numerical modelling of the embankment stability conditions.
Adaptation strategies are centred on the concept of suction-reinforced flood embankments, i.e. suction is considered an untapped natural reinforcement that can be successfully exploited to strengthen the embankments. In this respect, vegetation is considered a remedial measure in the sense that it promotes the generation of suction via evapotranspiration.
The approaches developed by RESCUE were validated against the case study of the Adige River embankment made available by the Agency for Civil Protection in Bolzano, Italy.