An industrial film that shows the construction, opening and extended use of the Derwent Reservoir in County Durham. The film includes the opening of the reservoir by Princess Alexandra in July 1967 and then goes on to examine the reasons for building it and some of the technical innovations and difficulties that had to be developed or overcome, by the civil engineers. A windswept view of Derwent Reservoir opens the film. A memorial stone set in a stone wall commemorates a nearby Friends...

An industrial film that shows the construction, opening and extended use of the Derwent Reservoir in County Durham. The film includes the opening of the reservoir by Princess Alexandra in July 1967 and then goes on to examine the reasons for building it and some of the technical innovations and difficulties that had to be developed or overcome, by the civil engineers. A windswept view of Derwent Reservoir opens the film. A memorial stone set in a stone wall commemorates a nearby Friends meeting house and the preaching of George Fox. Title: Derwent Reservoir Title: 18th July 1967 Princess Alexandra arrives by limousine to officiate at the opening ceremony of the reservoir. She joins a number of dignitaries on a covered platform, decorated in blue and white. The princess announces over a microphone that the reservoir is open. A military band provides a fanfare, and the princess goes on to speak to some of the men on parade. An overhead view shows the princess accompanied by a dignitary walking across a concrete footway above the main reservoir structure. The Princess’s speech accompanies the pictures. General view of the finished reservoir and its associated buildings and landscaped surroundings. People walk around the reservoir. A solitary man, Mr McClellan who is a key figure in the project, stops to look at the views near the reservoir. His voice provides more commentary, and the film goes on to show one of the buildings (Mill Shields Mill) which was lost in the flooding of the landscape. General views follow of the landscape. A series of maps show the proposed location of the reservoir. A project manager, on camera, gives an explanation regarding the decision process. Another gives information on the geological structure of the proposed site. Excess water in the clay has to be drained, so that the ground will take the weight of the new dam. Views show special drilling equipment being deployed to drill 4475 hundred ‘sand drains’ in the ground that will be filled with sand and gravel. The commentary states that the weight of the dam will squeeze the clay and the water will be dispersed into the drains and gives details of this part of the project. To create an embankment which is needed for the reservoir, a diagram shows that the river needs to be diverted in order to construct this. The film records the building of a tunnel to divert the river. A dragline excavator prepares the land for the construction of an outlet channel. On camera, one of the project managers talks about the difficulties of this part of the project, when more excess water had to be removed using special techniques. The film shows the pumps and other apparatus which had to operate for 24 hours to create the dry conditions needed to continue building. General views show excavators and trucks working on the channel. A screening plant washes and grades locally excavated material used to make the concrete. Lorries deliver the sand and gravel to the plant. They then take the washed and graded material to the concrete plant. The concrete is distributed to various parts of the project site. A small railway delivers tubs of concrete by gravity to where it’s needed. More views show the outlet channel being completed. A bulldozer, moves water and silt to the river diversion channel, and begins filling it in. Once the river’s new route has been established, the construction of the dam embankment goes ahead. On camera, project managers outline the problem of water escaping under the dam. Clay is used to line a special cutting to resolve the problem. The cutting is shown under construction where half a million cubic yards of spoil was removed, and replaced with rolled clay and backfill. A plan and one of the project managers explain more of the project. Water was removed from the sides of the channel to stop the sides of the cutting collapsing General views follow of heavy earth moving equipment scouring the landscape. The clay water barrier is checked by test drilling at various stages during construction. A man operates a special apparatus to check a sample of the rolled clay. Again, on camera, a manager outlines this aspect of the project. General views show heavy earth moving equipment at work shaping the landscape. At its peak the total vehicle fuel consumption on the site was a 5000 gallons a day. Tyre replacements were also particularly expensive. The machines at this stage work into the night, including a number of excavators working in the gloom with headlights on. General views show progress of the dam construction. Drainage ‘mattresses’ are constructed to help water dispersal. Commentary outlines this process. Commentary continues as technicians deploy special pressure test equipment to check on the stability of the dam during construction. One of the technicians places one of 200 measuring sensors in the fabric of the dam. Workmen lay 26 miles of nylon tubing in the trenches which is connected to sensors. These tubes will be connected to gauges housed in a specially built chamber. A construction worker checks an array of gauges and a piece of electrical apparatus. This apparatus showed that after an initial rise in pressure, the drainage systems were working correctly. Bulldozers create the reservoir embankments which covers the core of the construction. 180,000 concrete blocks are made on site to prevent wave damage to the reservoir. Workmen make special moulds to make the blocks, then fill the moulds with concrete. A crane lifts one of the blocks after the mould is removed, men brush the block clean then put it to one side. General views show the blocks being put in position on the banks of the reservoir. Because of the colour of concrete used in the blocks, the visual effect of the finished area is of a sandy beach. General views show work in progress to plug the diversion channel. Men work in hot and difficult conditions to get concrete to where it’s required. Water runs through the area they are working. Pipes that take water from the reservoir are laid, showing workers wading through water. General views show trenches dug into the landscape near the reservoir to take pipes to a water treatment plant at Mosswood a small hamlet nearby. General views show the construction of the treatment plant. General views show the finished buildings of the reservoir, dam and surrounding landscape, the river running freely, and a view across the new lake. Water splashes up against the concrete blocks on the sides of the reservoir. A lorry parks with its load of farmed fish, mainly brown and rainbow trout that will stock the reservoir. The commentary states that 45000 trout were used to stock the reservoir. 10,000, rainbows and 35000 brown trout. A man plants saplings in scrubland adjacent to the reservoir. A total of 20,000 are planted. General views show some of the men involved in the construction and project work. Commentary outlines the need to keep the men up to date with the project progress, and the problems all of those involved with the project have had. General views show the site buildings, after the main work has finished, looking like an abandoned town, and more of the reservoir and its buildings. Pipework runs through concrete tunnels. In a control room a man presses a button on a switchbox and water is released from the dam. Aerial views follow of the reservoir. Mr McClellan speaks to camera about the importance of the treatment of water after being stored in the reservoir. Small sailing boats are seen on the reservoir, as Mr McClellan continues saying that the pollution risks from such activity is minimal. Aerial views show boats on the reservoir. Title: This film was made for, the Sunderland and South Shields Water Company and the Durham County Water Board. Credit: A Gulliver Films Production