 The Land Drainage Act 1930 changed the administrative bodies responsible for drainage, and the Corporation effectively became an Internal Drainage Board.In 1941, the Corporation ceased to be, and its powers and responsibilities were split between the Trent River Catchment Board and the River Ouse (Yorkshire) Catchment Board.Despite this change, the management of the area continued much as before, with official records stating that the Catchment Board acted as the Corporation of the Level of Hatfield Chase, even though it no longer existed legally.