How long the Mo.S.E. barriers will be effective in protecting all urban settlements within the Venice Lagoon? The wind setup constraint

• Published in: Coastal engineering (Amsterdam) 2021-09, Vol.168, p.103923, Article 103923
• Main Authors: Mel, Riccardo A., Carniello, Luca, D'Alpaos, Luigi
• Format: Article
• Language: English
• Subjects: Climate change; Flood management; Mo.S.E. system; Venice Lagoon; Wind setup
• ISSN: 0378-3839; 1872-7379
• DOI: 10.1016/j.coastaleng.2021.103923

The last IPCC report highlights that, along the present century, sea level rise driven by climate change will exacerbate the flooding frequency in coastal areas. Among others, the Venice Lagoon is one of the most vulnerable because of the presence of worldly famous historical urban settlements. To face this, a mobile flap gate system (Mo.S.E.) is nearly completed and has already raised across the lagoon inlets under testing phase to protect Venice from flooding. However, relative sea level rise and the wind setup effect during the closure of the lagoon, pose relevant management challenges such as timing and frequency to operate the barriers. In the present work, we first highlight some issues related to the management protocol currently adopted. We suggest a new strategy that optimizes the gate operation by identifying the shortest duration of closure that simultaneously prevents the flooding of all urban settlements within the lagoon. The new strategy is then used to estimate the Mo.S.E. management considering the last 20-year-long tidal record, but also for investigating different scenarios of relative sea level rise. The analysis we propose proves that the enhanced wind setup constraint will lead the Mo.S.E. system to fail in controlling all flood events starting from a relative sea level rise of +0.40 m. In addition, wind setup will increasingly often produce long and repeated closures, requiring further measures to combine flood protection, port and industrial activities and the conservation of the lagoon ecosystem. •New method for the management of the Mo.S.E. barriers.•Wind setup enhances the duration of closure of the lagoon.•Climate change will rapidly increase duration and frequency of the closures.•Future challenge to combine flood protection with economic and environmental issues.•The Mo.S.E. barriers will fail in controlling any flood event starting from a relative sea level rise of +0.40 m.