The Engineering Design team were engaged in the development of a Rising Main at Lochar Moss Landfill Site. The requirement was for a pumping main to transfer contaminated surface water and landfill leachate from Lochar Moss to the public sewer network.

Client: Dumfries and Galloway Council Project Value: £320,000 Completion Date: 2004

The chosen route followed the A709 Dumfries – Lockerbie road. This choice was determined by the location of an outfall point to the sewerage system acceptable to Scottish Water and access to land for construction and maintenance.

A 1000m length of the A709 is built on peat. There were concerns that trenching the road would cause failure of the pavement structure and hence directional drilling techniques were employed.

The same directional drilling techniques were used to pass beneath both the A75(T) and the access to a recently constructed retail park. In both cases disruption to traffic during construction and damage to the road surface had to be minimised.

The total length of 110mm Ø pumping main was 2553m of which 1839m was constructed by directional drilling. In addition there was 111m of 150mm Ø gravity sewer together with a 5m deep wet-well equipped with twin submersible pumps to deliver the consented flow rate of 4l/s (350m3/day) against a static head of 12.882m.