History and background of the Welney Washes

The Ouse Washes is a linear 2,513.6 hectares (6,211 acres).

The site lies between the Old Bedford River in the north-west and the New Bedford River in the south-east. The Washes were created as a flood storage area and are often under water in the winter. This is part of flood and water management in this area of the Fens.

The creation of the Washes

Between 100,000 and 10,000 years ago, the sea level in eastern England was about 30 metres (98 ft) lower than at present. As the ice retreated during the Mesolithic, the sea level rose, filling what is now the North Sea. It brought the Norfolk coastline much closer to its present line. Coastal woodland was drowned by the returning sea. The woodland degraded to peat which overlaid deposits of marine clays and created the Fens.

Pre-18th century

Before the seventeenth century the Fens of eastern England were tidal marshland. They frequently flooded and were suitable for little more than summer grazing. 

In 1630, King Charles I granted a drainage charter to the 4th Earl of Bedford and his Adventurers. The Dutch engineer Sir Cornelius Vermuyden was engaged to complete the project. 

It was Vermuyden's idea to create a huge temporary floodwater storage area, surrounded by rivers. He cut another new channel, the Hundred Foot/New Bedford River. By constructing high 'barrier' banks on the outer sides of the enclosing rivers, and lower inner banks, the water could flow during flood conditions on to the land between them. The water was held until river flows and tidal conditions were low enough to allow drainage back into the rivers.

This creation of a 6,000-acre floodplain or reservoir, is commonly known now as 'The Ouse Washes'. Originally it was called the Hundred Foot Washes and is still known as that by many.