The River Tyne is 73 miles (118km) long and starts as the North Tyne, rising above the commercial forestry plantations of Kielder in the southern Cheviot Hills, and the South Tyne, rising in the remote uplands of the North Pennines near Garrigill. They join at Watersmeet just west of the market town of Hexham. Flowing east the river passes under the only bridge to survive the 1771 flood at Corbridge, and on to the tidal section and the start of the heavily urbanised areas of Newcastle and Gateshead the river is most famous for. Here it flows under a series of iconic bridges and on past the modern day Port of Tyne, the Fish Quay and out through the man-made harbour to the North Sea.
The catchment encompasses huge contrasts – the densely-populated urbanised stretches of Newcastle and Gateshead bear little resemblance to the remote and barren sheep-grazed hills of the North Pennines, or the extensive commercial forestry plantations of Kielder and the largest man-made lake in Europe. The entire catchment covers an area of 2,936km2 and contains 2,733miles(4,399km) of waterways in total.
History of the Tyne
The history of the River Tyne, and the industry that relied upon it, is well documented in scientific papers and books. What follows is a brief summary of some of the features of the history that drives some of our projects and ways of working.
The Tyne’s origins
The River Tyne started to cut its course about 30 million years ago. The land mass of Britain was rising from the sea, in which chalk rocks had been laid down during the previous Cretaceous period, providing the eastward-tilting ‘proto-landscape’ upon which the River Tyne began to carve its valley, entirely removing the softer cover of chalk rocks.
The river profile shows several deviations from the ‘ideal’ smooth decline of gradient, for example the steep section of the North Tyne at Warden Gorge compared to the much flatter upstream sections. When base level falls, rivers adjust by cutting down into their bed from the coast and working upstream. The influence of base level is also recorded in the lower reaches of the Tyne where excavations and drilling for the A1 motorway bridge foundations revealed a buried bedrock valley some 35m below current sea-level on the south side of the river. On the Tyne, these base level changes may equally be the result of glacial erosion, deposition or river diversion. These changes in base level and river gradient are critical to the way the river works now.
Shaping of the Tyne’s landscape
Natural river and glacial processes have helped shape the present landscape of the Tyne valley. Continuing fluvial processes have formed and modified the river channel and created habitats for river flora and fauna, whilst in the more modern era the processes themselves have been modified by changing land use and river engineering.
In the twentieth century, the slowly-operating natural processes were interrupted for several decades when gravel companies extracted large amounts of gravel from the river bed (2.2 million tonnes in 1922 rising to 106 million tonnes by 1968) as the use of concrete increased. The Tyne was a particularly attractive source for gravel, being a gravel-bed virtually from source to tidal limit and close to urban Tyneside. As a result the configuration and ecology of the river was greatly altered, as well as destabilising its structures.
The natural flow of the rivers and tributaries in the South Tyne were interrupted and diverted for the mining activities of washing, dressing, smelting and hushing. An interesting legacy is the metal and mineral content left in the mines, which still make their way through the river system. These metal-rich shingles create a unique habitat on which only specialised metal-loving plants can grow. Calaminarian Grasslands are protected SSSI features in our landscape.
Through the early years of the industrial revolution, Newcastle and other towns suffered incredible squalor and filth. The devastation of cholera epidemics in the mid-nineteenth century provided the impetus for the development of sewerage systems which transferred pollutants to the estuary. A potent mix of untreated domestic waste and effluents from Tyneside industry gradually deprived the river of oxygen and combined to form an environment toxic to most river life.
The first glimmer of environmental concern came in the twentieth century. The first surveys of dissolved oxygen, a key indicator of river health, were carried out from 1912 to 1931. Total depletion of dissolved oxygen was recorded on 16th October 1912. In 1933 the Joint Committee of the local authorities on Tyneside and the Tyne Fishery Board issued a report describing conditions in the estuary as “nauseating and thoroughly objectionable” … “the saturation point when untreated sewage can be discharged with safety into the estuary has been reached and passed.”
World War II interrupted the progress of cleaning up the estuary, but in 1958 the Tyneside local authorities started to examine possible schemes for sewage disposal. Following an objection by Associated Lead Manufacturers on behalf of the local Hayhole Works, a revised plan for the land-based sewage treatment works at Howdon at a cost of £46 million was given the go ahead in 1971. Although the historic driver for the scheme was water quality, the biggest impact of the Howdon treatment works is the regeneration and redevelopment of the banks of the Tyne, with positive economic and social consequences.
Just as these improvements were being achieved at the tidal end of the catchment, great changes were taking place towards the headwaters of the North Tyne. In the 1960s, water resource planning predicted a need for over a million cubic metres a day by 2001. In 1968 the National Rivers Authority concluded that the only way to meet this projected need was a river-regulating reservoir. The Kielder Scheme was born.
Kielder Water on the River North Tyne has a capacity of nearly 200 million cubic metres and covers an area of 10km2. The dam is 52 metres high and 1,140 metres long. It incorporates a hydro-electric generation plant. Since its completion in 1981 the scheme has changed the river flows and profile of the North Tyne.