George Leslie Ltd

Key Facts

  • Client: Scottish Water
  • Engineer: Jacobs / AECOM
  • Conditions of contract: NEC Option A
  • Contract value: £1,600,000
  • Duration of works: June 2015 - Oct 2016

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Reservoir Working

Pundeavon Reservoir – Dam Breaching

Located in the hills above Kilbirnie, North Ayrshire, Pundeavon Reservoir was constructed in 1907 with a 20m high earth-fill embankment dam. No longer required for raw water supply, this project was to breach the dam, reduce the impounding embankment and thus decommission the asset.

Due to the volume of silt encountered during the reservoir draw-down, an innovative solution was developed to divert the large inflows from the surrounding catchment to ensure the safe discharge of flows into the watercourse.

This involved the construction of temporary bund embankments at the upstream reaches of the reservoir to capture the flows which were then released in a controlled manner through a 400m temporary bypass channel.

An 80m long, engineered channel incorporating two stilling ponds was then formed through the reduced level dam embankment to convey the inflowing compensation water safely through the old reservoir bed formation. The breaching itself involved the excavation of some 30,000cum of material which was used as infill to re-profile the wider reservoir basin.


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