A £250million upgrade is transform Glasgow's water supply will help regenerate the city.

Major parts of the Greater Glasgow infrastructure are undergoing a vital transformation that is taking place largely out of sight.

Scottish Water is halfway through, what is the biggest investment in more than a century in the waste water infrastructure of Glasgow and it’s surrounding areas.

Much of the area's waste water system was built when Victoria was on the throne and is now in need of an upgrade.

Geoff Aitkenhead, Scottish Water’s asset management director, who launched the five year plan in 2013, said it would make the area’s waste water network “fit for the 21st century.”

At the centre of works is the biggest single project in the programme.

A £100m waste water or sewer tunnel called the Shieldhall Tunnel which will resolve large-scale water quality problems in the River Clyde and provide screening to overflows into watercourses.

It will also increase capacity and reduce pressure on the existing network by providing additional storm water storage.

The tunnel will also reduce the risk of flooding in Robslee Drive, Robslee Road, Robslee Crescent and Orchard Park Avenue in Giffnock and Aikenhead Road and Curtis Avenue in Mount Florida.

The Shieldhall Tunnel will be constructed between Queen’s Park and Craigton industrial estate via Pollok and Bellahouston parks.

It will be fives times as long as the Clyde Tunnel and the biggest waste water tunnel in Scotland.

It will be big enough to fit a double decker bus inside and with a storage capacity the equivalent to 36 Olympic size swimming pools.

Mr Aitkenhead said: “We’re making good progress with the biggest investment in Greater Glasgow’s waste water infrastructure in living memory.

“As we speak, we are pressing ahead with many key projects simultaneously across the area.

“The environment and communities throughout Greater Glasgow will benefit hugely from this because it will protect the natural environment and meet the needs of growth, economic development and regeneration.

"It will also support jobs and employment opportunities, including a number of apprenticeships.

“Some major projects have already been completed and the preparatory work for others is well under way.”

Dominic Flanagan, the project manager for the Shieldhall Tunnel project, said: “Being part of the Shieldhall Tunnel project is a once-in-a-lifetime work experience.

"While tunnelling projects are commonplace in large urban environments, this scale of tunnel is unlikely to be built again in Glasgow in my working lifetime.”

Other projects have included major environmental improvement work in Paisley, which will involve investment of £200,000 at two important parts of the town's wastewater infrastructure and an £820,000 project to reduce the risk of flooding at four properties in both Lethamhill Road and nearby Gartcraig Road in the Riddrie area of Glasgow.

Work is progressing every day on parts of the network right across Glasgow, West and East Dunbartonshire, Renfrewshire and East Renfrewshire.

An army of engineers are converting the ageing infrastructure into a modern and sustainable drainage system that will aim to improve the environment and biodiversity on the River Clyde and the rivers and streams flowing from it.

They hope it will also help tackle flooding, the effects of climate change and meet the needs of growth and economic development in the city and its neighbouring areas for generations to come.

The investment follows years of collaboration and studies by the Metropolitan Glasgow Strategic Drainage Partnership (MGSDP), Glasgow City Council and Scottish Canals.

A spokesman for Scottish Water said: “Without these improvements to our waste water infrastructure below ground, the Glasgow area would not be able to develop above ground in years to come”