Jan Adriaansz Leeghwater was a Dutch hydraulic engineer whom masterminded the land reclamation program along the flooded coast of the Netherlands. Leeghwater’s technique relied on heavy use of windmills to drain and pump water from the land. This involved the construction of polders—low-lying tracts of land that form an artificial hydrological entity—enclosed by embankments known as dikes and requiring drainage by pumps to maintain the water table within it from rising above the dikes. The land reclamation provided new fertile land and large-scale industrial processing of the products, which, in combination with shipping, gave rise to an unprecedented period of prosperity in the region known as the Dutch Golden Age. With this new wealth, the art of painting flourished, and a new class of wealthy merchants commissioned architects to build fine houses.

Leeghwater was born as Jan Adriaanszoon. Only later did he adopt the name Leeghwater, from laag water or low water. 

Sources

• Cleveland, Cutler (Lead Author); Peter Saundry (Topic Editor). 2008. "Leeghwater, Jan Adriaansz." In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth September 15, 2006; Last revised June 19, 2008; Retrieved March 22, 2009]. 
• Wikipedia Contributors, Jan Leeghwater, Wikipedia The Free Encyclopedia, Accessed 22 March 2009.