Editing River Little Ouse (section)

==Origins==
A distinctive feature of the headwaters of the Little Ouse and the Waveney is the [[valley]] in which they flow; the Little Ouse flows westwards while the Waveney flows eastwards. The valley is broad, cutting through [[boulder clay]] to the north and to the south, but is crossed by a flat sandy feature at Lopham Ford, between [[South Lopham]], Norfolk and [[Redgrave, Suffolk]]. Here the two rivers rise, barely {{convert|160|yd|m}} apart, at an altitude of around {{convert|85|ft|m}}. The B1113 road crosses the valley on the sandy bank, known as The Frith, and which is the only crossing of the Norfolk border which is on dry land. To the east are the [[wetland]]s of [[Redgrave and Lopham Fens]], while to the west is Hinderclay Fen. The whole area overlays a thick bed of [[chalk]].{{sfn |West |2006 |p=1}}

The geological features of a large through valley, but no large river, are unusual, and were first recorded by Rev. Osmond Fisher in 1868, a keen geologist who thought the features were related to glaciation, but failed to convince the geologists of the 1870s. More recently, Prof Richard West carried out a detailed field study of the area between 2002 and 2007, and his work was published by the Suffolk Naturalists' Society in 2009. He concluded that the valley was caused by the runoff from a large glacial lake, which eventually melted, leaving the valley as it is today, with the sands of the lake bed becoming the sands of the [[Breckland]], a large area of [[gorse]]-covered sandy [[heath (habitat)|heath]] that spans the border between Norfolk and Suffolk.{{sfn |West |2006 |pp=4-5}}<ref>{{cite web |url=http://www.lohp.org.uk/our-area/geology-and-landforms |archive-url=https://web.archive.org/web/20170622225305/http://www.lohp.org.uk/our-area/geology-and-landforms |archive-date=22 June 2017 |url-status=dead |title=Geodiversity in the Little Ouse Headwaters |publisher=Little Ouse Headwaters Project |access-date=7 October 2017}}</ref>

The downstream end of the Little Ouse has changed much over the centuries. In the Fens and Norfolk Marshland, it was quite possible for the course of a river to change as the result of a flooding episode so it is not surprising to find that the Great Ouse used to enter The Wash by way of the Old Croft River, the Wellstream and [[Wisbech]] (the Ouse beach). The modern lower Great Ouse was then the lower part of the Little Ouse. On this occasion, the change was artificial. The 17th century drainers under [[Cornelius Vermuyden]] dug the [[Old Bedford River]] between the Great Ouse at [[Earith]] and what had hitherto been the Little Ouse at [[Denver, Norfolk|Denver]]. A link was made for the Great Ouse between Littleport and the Little Ouse at Brandon Creek, and both the drainage and the navigation were directed towards [[King's Lynn]] rather than Wisbech.{{citation needed|date=October 2017}}