Storm Surge Barrier

A storm surge barrier is a large movable floodgate structure built across a waterway to prevent a storm surge or an unusually high spring tide from flooding the populated area it protects, typically forming part of a wider flood-defense system that also includes floodwalls and levees. The Oosterscheldekering in the Netherlands, roughly nine kilometers long, is the largest storm surge barrier in the world, and the Thames Barrier near London is the second-largest movable flood barrier; other major storm surge barriers protect New Orleans, Venice, and Saint Petersburg. Smaller, sometimes temporary versions can also be built around individual buildings rather than an entire city, and traditional stopgap measures such as sandbags have increasingly been supplemented by faster-to-deploy modular and water-filled barrier systems. No single clean origin date or inventor is established in the source consulted, since storm surge barriers developed as an application of ordinary floodgate engineering to coastal defense over many decades.