Channel Shallowing as Mitigation of Coastal Flooding

Journal of Marine Science and Engineering

Philip M. Orton⁴  Stefan A. Talke²  David A. Jay²  Larry Yin⁴  Alan F. Blumberg⁴  Nickitas Georgas⁴  Haihong Zhao¹  Hugh J. Roberts¹  Kytt MacManus³ 

[1] ARCADIS, 630 Plaza Drive, Suite 100, Highlands Ranch, CO 80129, USA; E-Mails:;Department of Civil and Environmental Engineering, Portland State University, Post Office Box 751, Portland, OR 97207-0751, USA; E-Mails:;Center for International Earth Science Information Networks, Columbia University, PO Box 1000, 61 Route 9W, Palisades, NY 10964, USA; E-Mail:;Davidson Laboratory, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, USA; E-Mails:

关键词: storm surge;    flooding;    tides;    adaptation;    wetlands;    bathymetry;    hurricane;    Hurricane Sandy;    Jamaica Bay;    New York City;   

DOI  :  10.3390/jmse3030654

来源: mdpi

【 摘 要 】

Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean Low Water; (3) shallowing only the narrowest part of the inlet to the bay. These three scenarios are deliberately extreme and designed to evaluate the leverage each approach exerts on water levels. They result in peak water level reductions of 0.3%, 15%, and 6.8% for Hurricane Sandy, and 2.4%, 46% and 30% for the Category-3 hurricane of 1821, respectively (bay-wide averages). These results suggest that shallowing can provide greater flood protection than wetland restoration, and it is particularly effective at reducing “fast-pulse” storm surges that rise and fall quickly over several hours, like that of the 1821 storm. Nonetheless, the goal of flood mitigation must be weighed against economic, navigation, and ecological needs, and practical concerns such as the availability of sediment.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.