From an agricultural polder to a tidal polder.

In 1803 the Tongplaat was reclaimed with a surrounding dike as an island in the middle of the Biesbosch. The polder was used primarily as pasture land for hay production. Because of the wet nature of the polder caused by natural seepage, the polder became important for wading birds such as godwits and even ruffs for their breeding display. In the last century the polder became much drier through drainage and the pasture land was ploughed and turned into arable land. 200 years after the creation of the polder plans were made to convert this agricultural polder of some 101 hectares into a tidal fresh water nature area. This plan foresaw a lowering of the ground level and the creation of a creek connecting the Nieuwe Merwede with the Zuidgat. On 9^th June 2012 the work was completed and officially opened. After some 2 years of digging and earth shifting a final piece of the surrounding dike was broken open. The Dordtse Biesbosch was then enriched with an extra 101 hectares of nature.