Megastructures

A historic and present look at Holland's efforts to hold on to their precious land from floods as a result of rising sea levels and climate changes. After a storm in 1916, the Dutch began a labor intensive construction of a Barrier Dam in 1923, stretching 30 km in length. It resulted in the reclamation of 165,000 ha of new land, and creation of a fresh water lake. However, in 1953, a combination of a hurricane and high spring tides caused the North Sea waters to force through the barrier and flood the Dutch coastline, resulting in the loss of over 1,800 lives and 47,000 livestock. The disaster resulted in Holland's creation of the 'Delta Project'. Costing billions of dollars, the project began in 1958. The project consisted of the construction of concrete dams, steel sea walls and retractable floodgates. Environmental considerations also led to the construction of the storm surge barrier in the Eastern Scheldt, one of the biggest in the world. It consists of 2 floating gates built on special docks. The vast gates are controlled by a computer system that allows the gates to be kept open but closes when a flood is imminent. Also presented are current emergency plans that include allocation of certain areas of land to be flooded during worse case flooding..

Behind the scenes of geothermal power complexes in California and Iceland, and a look at how scientists hope to expand its use by digging deeper into the Earth's crust.