Caledonia Water Alliance
Spring 2018

Aqueduct at Milltimber, as part of the delivery of the Aberdeen Western Peripheral Route

The W M Donald team is proud to have worked on many challenging projects that were part of the delivery of the Aberdeen Western Peripheral Route (AWPR). One of the challenges of this particular project was to divert the 800mm diameter gravity and 1200mm diameter pumped aqueducts that feed Aberdeen from the River Dee intakes at Invercannie Waterworks, Banchory.

At Milltimer the AWPR passes below the A93. A new overbridge was constructed on the A93 North Deeside Road. W M Donald carried out the temporary diversion of the 1200mm diameter aqueduct to facilitate construction of the new bridge and then relayed it over the new bridge deck with two 800mm diameter mains. Both the diversion and reinstatement over the bridge were carried out live, without disruption to Aberdeen’s water supply.

The brick gravity aqueduct which was constructed in 1866 was also diverted. This diversion comprised the construction of 1000mm diameter pipework below the AWPR in a syphon arrangement.

Key elements of this projects were:

  • Construction of complex cofferdam around existing aqueduct to facilitate ‘hot tap’ tee
  • Compliance with DOMS procedures
  • Interface with AWPR contractors
  • Maintaining flows in aqueduct