Coastal communities face a $400-billion tab over the next 20 years to protect their shores from rising sea levels, according to a June 20 report from the Center for Climate Integrity and the engineering firm Resilient Analytics. The report says 50,000 miles of coastal barriers will have to be built by 2040. Jacksonville, Fla., New York City, Virginia Beach and Galveston, Texas, will have the biggest seawall tabs. But the report doesn’t tell the whole tale. While floodwalls have a 100% proven track record worldwide, “enhanced climate data projections, as well as integrated planning principles and systems engineering, continue to refine the flood protection options cities have, blending gray and green strategies and working with nature rather than against it,” says Edgar Westerhof, U.S. Flood Risk & Resiliency Lead for Arcadis.