George Leslie Ltd

Key Facts

  • Client: Scottish Water
  • Engineer: Jacobs
  • Conditions of contract: NEC 3 Option E
  • Contract value: £1.72m
  • Duration of works: February - September 2017

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Water Supply & Pipeline Work


The new Glencorse Water Treatment Works provides water into supply for the greater part of south Edinburgh, including Edinburgh City Centre, the Old Town, Canongate, Liberton, Prestonfield, and The Inch. Following commissioning into service, enhanced measures were required on the large diameter treated water trunk mains supply to increase resilience and reduce the risk of service disruption and flooding due to bursts.

One such measure was the installation of a new Pressure Reducing Valves (PRV) facility at the former Alnwickhill water treatment works site in Liberton. This solution involved a 20m x 15m x 5m deep excavation within a sheet-piled cofferdam within a confined construction site bounded by the main A701 route into Edinburgh and new-build housing to enable the construction of a large reinforced concrete chamber to house the new PRV system together with the ancillary pipework and supports, and including the MEICA and MCC kiosk requirements.

The main elements of work included:

  • Sheet-piled excavation around the live, 1m diam trunk main
  • Installation of six early-strength concrete pipe supports
  • 2 x hot-tap tee installations into the live1m diam steel main
  • 1000mm diam in-line valve installation to divert flows through PRV chamber
  • Installing by-pass pipework
  • Constructing the 8m x 6m x 4m deep R.C. PRV chamber
  • MCC Kiosk, hardware and software upgrades
  • Final commissioning of the new two-stage PRV system.

Successful completion of the project required careful working to maintain the integrity of the essential trunk supply main and minimising disturbance within this confined location.

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