Spennymoor, County Durham
The 30-inch South Derwent Trunk Main that crosses the River Wear had become exposed following river bank erosion after heavy rainfall. There was concerns that further rainfall and flooding would continue to erode the ground and put pressure on the scour pipework and thrust blocks, resulting in major failure of the Trunk Main.
Esh-Stantec was appointed to undertake the emergency repairs and the solution involved reshaping the river to redirect the flow, as well as the construction of a rock armour wall to form a new river embankment to protect against further erosion.
The scheme involved:
· Construction of a reinforced concrete slab over the Brancepeth Beck.
· Installation of a 320m stone access road.
· Construction of a concrete protection slab over the 30-inch water main.
· Installation of temporary cofferdam using 700 no.1 tonne sand and gravel bags.
· Importing and installation of rock armour protection.
· Importing and placing of backfill behind the rock armour.
We liaised closely with the nearby farm to ensure that they always had access and our deliveries didn’t conflict with their activities. We also had to liaise with Northern Power Grid to obtain approval to go underneath their overhead lines. Throughout the duration of the works we worked closely with the Land Agent for the Brancepeth Estate and had frequent visits from various Environment Agency departments.