By Christopher Flavelle
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The study points out that sea levels are expected to increase 1.3 feet by 2035, and as much as 2.6 feet by 2065. It proposes five options to protect the Navy Yard; four of those options entail surrounding most of site with a permanent wall, as well as pump stations to move whatever water makes it over or around the wall.
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The wall proposal also demonstrates the threat that climate change poses to Washington itself, and the difficulty of responding to that challenge. The Navy Yard is less than two miles southeast of the U.S. Capitol, and just east of the stadium where the play. The area is also home to new condominiums and office buildings, along with high-end shops and restaurants. The Naval Facilities Engineering Command document, dated Feb. 27, 2018, and based on a flood risk management study prepared for the Navy by the U.S. Army Corps of Engineers, found that a so-called 10-year storm -- one with a 10 percent chance of happening in any given year -- would cause seven feet of flooding at the Navy Yard. A 100-year storm would bring 10.5 feet, and a 500-year storm 14 feet of flooding.
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Larry Larson, a senior policy adviser with the Association of State Floodplain Managers, called it a “reasonable assumption” that a wall would make nearby structures more vulnerable to flooding. The important question, he said, is whether the Navy has analyzed what the impact would be to those other properties. If the Navy decided that a wall was too problematic, the study suggests its other options are limited. The only proposal that doesn’t involve a wall is to try to flood-proof existing buildings with a mix of waterproof doors and windows, elevating structures and other changes.
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