The New Bedford River, also known as the Hundred Foot Drain because of the distance between the tops of the two embankments on either side of the river, is a man-made tributary of the River Great Ouse in the Fens of Cambridgeshire, England.

The channel was created in around 1650 by Cornelius Vermuyden as part of a project to reclaim the lands of the Bedford Level that were reclaimed in the 1630s and deliberately flooded during the Civil War. The workers on the project were predominantly Scottish prisoners-of-war captured at the Battle of Dunbar.

Both this river and its "twin", the Old Bedford River, are named after Francis, Earl of Bedford who funded the construction of both rivers. The area between the two rivers (20m long, 1m wide) is above sea level and is flooded during winter. At Welney, these "washes" provide an ideal habitat for wildfowl and other birds, and the Wildfowl and Wetlands Trust has established a nature reserve here, the WWT Welney. A walking trail runs along its entire length.