WASHINGTON — Galveston, Texas, is betting on the Ike Dike, a proposed 60-mile storm gate named after the raging hurricane that walloped the island and the rest of the Houston area four years ago, leaving more than 70 people dead and $30 billion in damage.

Norfolk, Va., is trying to strengthen its string bean of a storm-drainage system that can’t absorb mild flooding from high tides, much less days-long deluges from hurricanes or nor’easters.