Some areas below sea level will be indefensible as ocean’s rise due to climate change. Following the example of the Dutch Delta Works, some places will be guiding rather than holding back floodwaters. New Orleans plans a combination of levees, some with breeches to let waters flow through. Giving up may be hard to do, but letting go and letting water in can prove a cost savings in the long term with environmental bonuses to the surrounding communities.
In Great Britain, the Medmerry Managed Realignment Project was finished this week. It protects the Manhood Peninsula in the English Channel by opening 452 acres of land as a basin for floodwaters and changes hundreds of years of building and rebuilding barriers breached 14 times since 1994 to creating a natural area visitors can enjoy. The acreage turns to tidal marsh and will become a huge wildlife refuge managed by the Royal Society for the Protection of Birds. It will include bike trails, walking paths and observation points.
There were costs involved in acquiring the land, but the maintenance of the old barrier required constant trucking in of shingles at an annual cost of three hundred thousand pounds. Damages from one breech alone in 2008 severed the only access road causing businesses over five million pounds in losses.
See also InClimate 304, 228, 224, 194, 161, 149, 86, 77 (Progressive Dutch & Climate) Nov. 1 (Floodplains) Aug 17 (Mekong Mississippi River Commissions) Aug. 13 (Too much, too fast, too intense water Toronto) July 14 (2 “Once in a Century” European Floods) June 11 (Droughts & Floods) May 30 (Permeable Paving) Mar. 28 (Dutch Delta Works Lets Water In) Mar. 19
http://thinkprogress.org/climate/2013/11/05/2893261/flooding-medberry-managed-reallingment/