Operational flood management under large-scale extreme conditions, using the example of the Middle Elbe

Abstract

Abstract. In addition to precautionary or technical flood protection measures, short-term strategies of the operational management, i.e. the initiation and co-ordination of preventive measures during and/or before a flood event are crucially for the reduction of the flood damages. This applies especially for extreme flood events. These events are rare, but may cause a protection measure to be overtopped or even to fail and be destroyed. In such extreme cases, reliable decisions must be made and emergency measures need to be carried out to prevent even larger damages from occurring.Based on improved methods for meteorological and hydrological modelling a range of (physically based) extreme flood scenarios can be derived from historical events by modification of air temperature and humidity, shifting of weather fields and recombination of flood relevant event characteristics. By coupling the large scale models with hydraulic and geotechnical models, the whole flood-process-chain can be analysed right down to the local scale. With the developed GIS-based tools for hydraulic modelling FlowGIS and the Dike-Information-System, (IS-dikes) it is possible to quantify the endangering shortly before or even during a flood event, so the decision makers can evaluate possible options for action in operational mode.

Hydrological simulation of extreme flood scenarios for operational flood management at the Middle Elbe river

“…For this IC, a large-scale and taskspecific stochastic-conceptual precipitation-runoff (SCPR) model was developed. Distributed daily input of the IC was derived by interpolation of observed precipitation depths (inverse-distance Kron et al, 2010) shows the reach of the Middle Elbe river which was chosen as case study area of the joint research project to which the work of present paper contributed. method) and temperatures (modified nearest-neighbour method with altitude gradients) to a 5 × 5 km grid.…”

“…These hydrological simulations contributed to the joint research project "Operational flood management under large-scale extreme conditions, using the example of the Middle Elbe" (funded by the German Ministry of Education and Research) with further sub-projects on meteorological, hydraulic and geotechnical (dike monitoring) issues. A summary of advancements and coupling of tools as well as interdisciplinary derivation and evaluation of extreme flood scenarios performed in this joint research project can be found in Kron et al (2010). Present paper emphasises the largescale hydrological simulation technique newly developed for the German part of the Elbe basin (see Sect.…”

“…Map of the Elbe basin upstream of the Elbe gauge Aken including the main Elbe tributaries and their catchments, selected gauges and the low mountain range in the intermediate catchment of the Elbe gauges Dresden and Aken. Detailed map in the lower part (provided byKron et al, 2010) shows the reach of the Middle Elbe river which was chosen as case study area of the joint research project to which the work of present paper contributed.…”

Spatio-topological network analysis of hydrological infrastructure as a decision support tool for flood mitigation in coastal mega-cities

“…These infrastructure components are often widely distributed within coastal cities (Hung et al, 2009) and connected spatially through waterways, creating a complex topology of networked systems (Barrat et al, 2004). As the real-time operation of flood control systems is crucial for mitigating the damaging impacts of floods (Shim et al, 2002), the inability to understand this network complexity may result in imprecise operational decisions leading to the failure of the hydrological infrastructure system during flood events (Akmalah and Grigg, 2011;Kron et al, 2010;Kundzewicz, 1999). This situation presents a significant problem in coastal mega-cities in which the consequent failure of the hydrological network exacerbates flood hazards, causing significant loss of life and damage to property worth billions of dollars (Brinkman and Hartman, 2008;Few, 2003;Ward et al, 2011).…”

“…Imprecise operational decision making during flood events may also lead to the failure of the hydrological network (Akmalah and Grigg, 2011;Kron et al, 2010), which in turn may result to a breakdown in other important infrastructure systems such as energy, transportation, and communication networks (Caljouw et al, 2005;Chen et al, 2005). Therefore, in designing a solution to improve real-time operational decision making in flood control systems, the capability to understand the interdependencies between hydrological networks and other critical infrastructure is crucial.…”