George Leslie Ltd

Key Facts

  • Client: Scottish Water
  • Engineer: CH2M - MWH
  • Conditions of contract: NEC Option C
  • Contract value: £8.5m
  • Duration of works: May 2012 - September

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Wastewater Pipelines, Tunnels & Shafts

Shieldhall 1 UID Programme

An 18 project Design & Build programme of work to reduce the frequency of unsatisfactory intermittent discharges (UIDs) from combined sewer overflows (CSOs) on the main sewer network on the south side of Glasgow to reduce the environmental impact on the River Cart tributary of the Clyde.


Outline solution development involved extensive investigation to confirm ground conditions and verify the location of existing services with each discrete project solution verified under the holistic drainage area catchment model to ensure mutual compatible & interdependency.


Typically each discrete project comprised upgrading & upsizing of the existing sewer and the construction of a large attenuation chamber with screened overflow outfall pipeline to the nearby watercourse.


Challenges included:

  • Pipelaying and chamber construction in busy suburban main roads with extensive & complex traffic management
  • Deep construction in variable ground conditions
  • Careful stakeholder management in sensitive residential areas

News updates


The overall project involves the off-site fabrication and installation of a new linkspan structure at Oban Ferry Terminal for client Caledonian Maritime Assets Ltd (CMal).

12th February 2019

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GL return to the Sound of Kerrera

GL making a return visit to the Sound of Kerrera off Oban, to undertake substantial repairs to the breakwater which suffered collision damage following an altercation with a workboat earlier this year.

14th December 2018

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Polmadie Bridge official opening……..

Michael Matheson MSP and Cabinet Secretary for Transport, Infrastructure and Connectivity covered all his portfolios at the official opening of the new Polmadie Footbridge giving pedestrian and cycle transport access,

18th September 2018

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George Leslie Ltd, Blackbyres Road, Barrhead, Glasgow, G78 1DU  |  |  +44 (0)141 881 9131