River Tees - Alterations

Alterations

In the early 19th century the river was straightened, thus saving money and time in navigation. Between Stockton-on-Tees and Middlesbrough, the river previously meandered first south and then north of its current channel. Two "cuts", known as the Mandale Cut and the Portrack Cut were made to straighten its course. Before these cuts were made, the journey by sailing barge from Thornaby to Middlesbrough, allowing for tides and other factors, could take as long as the journey from the mouth of the Tees to London. The Mandale Cut was the shorter of the two, at about 200m, with the Portrack Cut being considerably longer, although the northern meander it removed was smaller than the southern meander. Neither meander is visible today, except for the flow of Stainsby Beck into a waterway which is marked on maps first as "The Fleet" and then "Old River Tees". The current Tees Barrage is close to the site of the Mandale Cut.

Since the cuts were made, the river has continued to undergo alterations on its bed and banks to make it deeper and more navigable. The channel has been made considerably narrower by dumping ship's ballast and ironworks slag along the former banks, increasing the scouring due to its natural flow. Maps made prior to 1900 show that between Stockton and Middlesbrough the river flowed in a channel up to 330 yards (300 m) wide in places, with many shoals and sandbars. The modern channel varies between 110 yards (100 m) and 220 yards (200 m) or even a bit more.