Instead of Levees, Plant Trees

According to new research, coastal forests greatly reduced the impact of the Japanese tsunami.

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Reuters

When a tsunami overtook northeastern Japan back in March 2011, water rushed inland more than 1 kilometer in some places. But not all areas suffered equally. According to new research out of Chiba University, areas with coastal forests actually experienced less flooding than those with levees and seawalls.

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As The Mainichi reports, Professor Yoshihisa Maruyama compared satellite imagery of coastal areas in Japan against official flood maps created after the tsunami. Places without coastal forests – even if they had levees in place – saw flooding from 700 to 1,000 meters inland. Areas with forests along and near the coastline only flooded about 400 to 500 meters in.

Maruyama studied a 13-kilometer section of coastline in the city of Asahi, in Chiba prefecture, and found that even building devastation was much less severe in areas with coastal forests.

These findings could be important for coastal areas all over the world. While the threat of tsunamis may be higher in the Asia Pacific, weather- or climate change-related flooding is a ticking time bomb in cities across the world. But what if diminishing the impacts of these devastating events could be as simple as planting a bunch of trees?

About the Author

  • Nate Berg is a freelance reporter and a former staff writer for CityLab. He lives in Los Angeles.