English sea walls get wired to measure flood risk in real time
On the shores of Liverpool Bay, ‘WireWall’ device helps engineers mount a battle against the waves.
Jenny Brown is hoping for really bad weather. She is consulting tide tables, watching forecasts and rooting for strong westerly winds that would push the spring tide over the sea wall at Crosby, on Liverpool Bay, in the days around 21 March.
Brown, a physical oceanographer at the National Oceanography Centre (NOC) in Liverpool, wants to help local officials understand how much the ocean is breaching the sea wall — and how much they need to strengthen their flood defences.
To do that, she needs the waves to splash onto a device her team will bolt into the concrete sea wall. It’s a boxlike frame built of pipes, with wires strung between them like strings on a harp. When seawater slops over the top of the barrier, the wires will measure the volume and speed of the spray.
Such data are important to make sure that people strolling by the sea aren’t swept off their feet by big waves, and to help communities prepare for coastal flooding during storms. In the United Kingdom alone, at least £150 billion (US$197 billion) of property and 4 million people are at risk from coastal flooding. “Nobody’s going to make the call to shut a four-lane highway unless they’re really sure the conditions are likely to be hazardous,” says Tim Pullen, a coastal engineer at HR Wallingford, a civil-engineering company in Wallingford, UK.
By: Alexandra Witze/Nature News