Flood mitigation designs with respect to river ecosystem functions—A problem oriented conceptual approach

Abstract

We formulated five proposals to improve specifications of flood hazard reduction projects and five proposals to preserve the river ecosystem functions, based on literature and authors' experience. Starting from these, we established a conceptual approach using the notion of riverscape, with related function richness and bioassessment tools.We defined four riverscape types based on the gradient of artificialness, from type I (impervious bed) to type IV (less than 30% or no artificial bed). To apply our approach to dry dam designs, we individualized different parts of dry dams and characterized them by an ideal riverscape type, according to the hydraulic constraints of each part.Type I is unavoidable in the bottom outlet, and types I or II at the foot of the dam.Types III (30% -50% of artificial bed) and IV were recommended at upper and lower parts of the dam, according to the risk of bank erosion and need for bank reinforcements. The approach appeared efficient to help biologists and hydraulic practitioners work together, and find technical solutions complying with both flood protection and biodiversity preservation requirement.

Co-conception of integrated flood management solutions: riverscapes to facilitate dialog

“…However, in modest projects, the funds are limited and people often have little background of pluridisciplinarity. So, the issue is for each one to transmit the proper amount of knowledge to the others in an understandable and usable form (Poulard et al 2010). For discussions about the design to be fruitful, every specialist has to state his own constraints and understand the needs of the others: in biology, hydrology or civil engineering.…”

“…We propose a method to facilitate this co-conception, based on the defi nition of "riverscapes", formulated in the fi rst place for dry dams (Poulard et al 2010). …”

Bedeutung des Geschiebetransportes für die Planung von Hochwasserschutz- und Retentionsmaßnahmen in Talflüssen – Numerische Modellierung des Inns im Tiroler Unterinntal

“…Im Rahmen integraler, nachhaltiger und ökologisch verträglicher Planungsansätze werden sie mittlerweile gemeinsam mit anderen flussbaulichen und raumplanerischen Maßnahmen, beispielsweise der Schaffung ökologischer Ausgleichsflä-chen oder der Freihaltung von Flächen für die Hochwasserretention, betrachtet (Aufleger et al 2012;Geilen et al 2004;Poulard et al 2010;Zarn 2008 (1) Als Ergebnis der Sensitivitätsana-lyse wurden drei Szenarien definiert, welche ein Spektrum der im Hochwasserfall zu erwartenden Sohllagenän-derungen abbilden und mit welchen die morphodynamischen Änderungen für IST-und PLANzustand analysiert werden. Folgender Parametersatz wurde für alle Simulationen übernommen: θc = 0,047; kst = jeweils zeitlich konstant mit Werten entsprechend der Reinwasserkalibrierung; αL = 4000 und Lso = 15.…”

A decision-support methodology for assessing the sustainability of natural risk management strategies in urban areas

“…For instance, some effects and aspects seem to be significant but remain difficult to assess, particularly regarding the social and institutional dimensions (Lekuthai and Vongvisessomjai, 2001 cited by Poulard et al, 2010). Because some of the indicators are related to intangible concerns (e.g.…”