NYT: “Mayor Michael R. Bloomberg outlined a far-reaching plan on Tuesday to protect New York City from the threat of rising sea levels and powerful storm surges by building an extensive network of flood walls, levees and bulkheads along its 520 miles of coast. The mayor said the plan would initially cost about $20 billion, and eventually far more. The city would spend the money on fortifying infrastructure like the power grid, renovating buildings to withstand hurricanes and defending the shore, according to a 438-page report on the proposals.”