Impact of sea level rise on tide gate function

Area of Science:

• Environmental Science
• Hydrology
• Climate Science

Background:

• Tidal communities face increasing flood risks due to climate change-induced sea level rise and land subsidence.
• Flood prevention infrastructure, such as tide gates, is crucial for low-lying coastal areas but can be compromised by rising sea levels.
• Existing tide gates regulate water flow, closing during high tides and opening during low tides to manage flooding and drainage.

Purpose of the Study:

• To assess the impact of rising mean sea level elevations on the effectiveness of tide gates in preventing upstream flooding.
• To model a specific tide gate system and its associated drainage area in the New Jersey Meadowlands.
• To identify critical sea level thresholds that exacerbate flooding scenarios.

Main Methods:

• Development of a coupled HEC-RAS and HEC-HMS model for a tide gate structure and its upland drainage area.
• Simulation of various sea level rise scenarios to evaluate tide gate performance.
• Analysis of hydraulic impacts on tide gate functionality under elevated mean sea level conditions.

Main Results:

• Model predictions indicate a significant reduction in tide gate effectiveness with rising sea levels.
• Simulations show that sea level rise will lead to longer-duration and deeper flood events in the modeled area.
• A critical sea level elevation threshold was identified, beyond which flooding impacts become dramatically worse.

Conclusions:

• Sea level rise poses a substantial threat to the functionality of tide gates and the resilience of tidal communities.
• The New Jersey Meadowlands faces dramatically worsened flooding scenarios if critical sea level thresholds are crossed.
• Urgent adaptation strategies are needed to mitigate the severe impacts on living standards and economic activities in densely populated coastal regions.