River Tees - Geography

Geography

It drains an area of 708 square miles (1834 square km) and subsumes no important tributaries. Before the reorganization of the historic English counties, the river formed the boundary between County Durham and Yorkshire. In its lower reaches it now forms the boundary between the ceremonial counties of County Durham and North Yorkshire, while in the highest part of its course it forms the boundary between the historic counties of Westmorland and Durham. The head of the valley, whose upper portion is known as Teesdale, has a desolate grandeur, surrounded by hills, some exceeding 2500 feet (762 m), and bleak moorland. This area is part of the North Pennine Area of Outstanding Natural Beauty, recently designated a geological Europark, the first in the UK. In the headwaters is the Cow Green Reservoir constructed to store water to be released in dry conditions to supoport industrial need for water on Teesside.

A succession of falls or rapids, where the river traverses a series of hard black basalt rocks, is called "Cauldron Snout". From immediately below this to its mouth, the Tees forms the boundary between the traditional counties of Durham and Yorkshire almost without a break, although since 1974 much of it lies wholly in Durham. The dale becomes bolder below Cauldron Snout, and trees appear, contrasting with the broken rocks where the water dashes over High Force.

The scenery becomes gentler and more picturesque as it descends past Middleton-in-Teesdale (Durham). This locality has lead and ironstone resources. The ancient town of Barnard Castle, Egglestone Abbey, and Rokeby Hall, well known through Sir Walter Scott's poem, are each passed; and then the valley begins to open out, and traverses the rich plain east and south of Darlington in sweeping curves.

The course of the valley down to here has been generally east south east, but it now turns northeast and, nearing the sea, becomes an important commercial waterway, with the ports of Stockton-on-Tees and Middlesbrough on its banks. It passes through the Tees Barrage between these ports, turning tidal downstream from the barrage.

Teesport is built on reclaimed land on the south side of the Tees estuary below Middlesbrough.