 From the beginning, there were tensions between those who wanted to use the rivers for navigation and those who wanted to use them for drainage, to the extent that when Denver Sluice was demolished by an extremely high tide in 1713, the towns of Cambridge and Thetford petitioned against its reconstruction.However, a more serious problem for the Burnt Fen area was the steady shrinkage of the land surface as the water was removed from the peat soils, and the blowing away of the light soil as it dried out.Water could no longer flow by gravity from the land into the rivers.