Coastal cities trial floating parks to absorb tidal surges

Four port authorities on the North Sea coast have installed anchored, buoyant platforms planted with reeds and dune grass along stretches of seawall that flood most winters.

The platforms rise and fall with the tide rather than resisting it, and early monitoring suggests they cut wave energy reaching the wall behind them by close to a third during the season's first serious storm.

Engineers caution that a single storm season is not proof of concept, but say the design's main advantage is cost: retrofitting existing walls is far cheaper than replacing them outright.