Flood Proofing Cities

London: Solution
In the 1970s, the so-called Thames Barrier, seen here, was built across the river to protect London from the kind of disastrous flooding that last occurred there in 1953 (when Holland also flooded) and took over 300 lives. But scientists say that the defense the barrier provides is gradually declining, and it may not be able to continue to block rising tides past the year 2030. Officials have charged a commission with finding a longer-lasting solution, and a proposal is under consideration to build a more extensive, 10-mile gated barrier along the Thames.