The works, which will supply Edinburgh and parts of north Midlothian with fresher, clearer drinking water, is being built underground at Glencorse, near Flotterstone.

Residents in Loanhead, Bilston, Damhead, Seafield and the Bush Estate will benefit from the new works, which are scheduled to be completed in 2010 and come on line in 2011.

Latest technology

The new WTW will replace the Victorian works at Fairmilehead and Alnwickhill in Edinburgh.

Scottish Transport, Infra-structure and Climate Change Minister Stewart Stevenson officially marked the start of the building work, which uses the latest in environmental technology to ensure the WTW blends in with the local countryside.

Mr Stevenson said: "The Glencorse works will incorporate all the best thinking in terms of reducing energy use and the latest technology, while delivering higher quality water for Edinburgh and the surrounding area."

Scottish Water chairman Ronnie Mercer added: "This is a landmark day for our customers.

Green roof

"This premier project will continue to protect public health by supplying safe drinking water from a more modern treatment works.

"Thanks to modern filtration this clearer, fresher, drinking water will look and taste better for decades to come."

For the past 18 months, Scottish Water has worked closely with the community to ensure disruption during construction and the final works meet local approval.

World first

This included fitting a "green" roof, made of grass and sedum, to ensure the works blend in with the countryside.

The diverted rainwater will create a new wetland habitat for birds.

In a world first, a temporary mobile pipe manufacturing plant will be constructed, near Bilston, which will reduce lorry journeys by 75 per cent.

An on-site turbine will supply a third of the Glencorse plant's energy needs.

For full story, see The Advertiser, October 9, 2008