George Leslie Ltd

Key Facts

  • Client: Noddsdale Hydro Ltd
  • Engineer: Inter Hydro Technology of Kendal
  • Conditions of contract: NEC3
  • Contract value: £275,000
  • Duration of works: July 2010 – October 2010

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General Civil Engineering, Renewables & Environmental

Noddsdale Hydro Scheme

This contract was for the construction of a new hydro-electric generating system to replace one originally constructed in 1927 at Noddsdale Estate, Brisbane Glen Road, Largs, Ayrshire.

The replacement scheme was commissioned by the Estate to provide a long term revenue stream through the provision of ‘green’ electricity to the National Grid.

All of the work was carried out in a controlled manner with great emphasis placed on ensuring the Estate’s visitors, residents and local farmers enjoyed safe unencumbered access to the lands affected by the construction of the scheme.

The works comprised construction of a new intake works at the head of the scheme incorporating a ‘V’ notch plate to maintain a permanent compensation flow to the Noddsdale Burn, with all remaining flows available to be diverted over the intake weir wall into 260lin.m of 250mm diam HDPE butt welded black pipe.   From the intake works the flow is transferred to the existing reservoir for storage until required to drive the new turbine.

The reservoir has an outlet bellmouth 2.50m below spillway level, approximately 150m above the turbine, and a scour pipe 1.50m below the intake. The scour outlet was buried in silt that had been collecting from 1927 and George Leslie Ltd was charged with removing this from the reservoir and depositing this to a designated storage area within the Estate. Some 4,700 tonnes of silt and debris was removed from the reservoir floor during the course of the contract and the scour pipeline was cleaned and its operation reinstated. An air valve and strainer has been built into the pipeline, 20m downstream of the reservoir intake to facilitate emptying the pipeline and clearing the strainer.

From the reservoir a further 900lm of continuously welded 250mm dia HDPE pipe was laid to a gradient falling at 1 in 6 to the new purpose built power house constructed to house the turbine generator. The residual flow then drops into the tailrace below the turbine and discharges, through the reinforced concrete outfall headwall, back to the Noddsdale Burn. The power from the generator is then carried to an existing National Grid connection point 25m from the power house.

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