George Leslie Ltd

Key Facts

  • Client: Scottish Water
  • Engineer: Aecom
  • Conditions of contract: NEC Option C
  • Contract value: £1,385,000
  • Duration of works: Feb - Nov 2014

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Wastewater Treatment Works

Echt Wastewater Treatment Works

Design & Build of a new wastewater treatment works to provide increased capacity in the system to enable development growth in the surrounding area.

Echt WwTW was refurbished in 1994 with further work being done on the inlet in 2005. The works comprise: inlet works with screening, primary tanks, biological filter, humus tanks and pebble bed clarifier. Treating ‘Formula A’ flows, the new works were built adjacent to the original smaller works, which were decommissioned following relocation of the existing Haigh screen and transfer of flows.

Key elements:

  • Relocation of the existing Inlet Screen
  • 2 x 60,000 litre septic tanks
  • An 11.5m biofilter with p.c. walls
  • 6m diam humus tank
  • Effluent pumping station and outfall
  • New power supply, MCC & kiosk
  • 1km of 125mm final effluent HPPE rising main to Gormack Burn
  • New 4m wide road & hammerhead for turning articulated tankers

The environmental impacts from the construction of these works were small and of short duration, namely the storm water overflow into the burn adjacent to the site and the final effluent rising main pipeline laid through the adjacent trees, with the following items given due consideration.

  • Restricted site access via single-track road off the B9119
  • With the site surrounded by bushes, trees and a nearby burn, with potential for providing a suitable habitat for nesting birds, red squirrels or bats, badgers and otters a protected species survey was carried out prior to the start of construction.
  • Tree clearance took place early in the contract before the nesting seasons.
  • Conformity with the CAR Engineering Licence, ensuring that all outfall or burn bank works were restricted to the summer months.

Significant Risks Mitigated:

  • Abandoned pipelines and overhead power
  • Confined space workings
  • Work adjacent to water course
  • Unchartered site services
  • Dealing with existing structures previously modified




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