A MASSIVE engineering project is to be launched to completely overhaul the huge Haweswater Aqueduct, which runs through the heart of South Lakeland.

The multi million project, one of the largest ever to be to be undertaken in United Utilities’ history, has been necessitated by age of the underground pipeline, which runs for 67 miles from the Cumbrian reservoir to a water treatment works north of Manchester.

United Utilities has confirmed that some work has already taken place in the Kendal area, but the scale of the whole project is so large a huge amount of preliminary survey work, planning and tendering is to be undertaken before the main pipe replacement work can go ahead.

The aqueduct, which is underground for most of its length, has long been regarded as an incredible feat of engineering.

It transports water from the reservoir deep in the Lake District fells, initially through Longsleddale then further south, eventually reaching Manchester.

The construction of the aqueduct followed the creation of Haweswater Reservoir by a then controversial scheme to dam the valley of Mardale.

The flooding of the valley meant the picturesque and historic villages of Measand and Mardale Green were lost beneath the rising waters when the dam came into operation.

Hundreds of people were forced to leave their homes and 97 bodies were transferred from the graveyard and reinterred at Shap.

Work on the aqueduct was started in 1935 and was completed in 1955, and is capable of carrying 570 million litres a day, with much of the pipeline of such a wide diameter it is big enough to walk or drive down.

And in a much feted feat of engineering, the aqueduct is so designed that the weight of the water over the 550 metre drop from Haweswater Reservoir sucks the water under a number of river valleyss, meaning the operation is in effect a huge syphon.

However, such a huge and lengthy structure has required constant maintenance over the years.

In the autumn of 2013, 80 specialist engineers, who were at the time dubbed ‘aquanauts,’ descended into the vast tunnel and then were transported along it using special buggies in a two week survey, cleaning and repair operation which caused no disruption to the public.

The process was repeated in 2016, this time on a larger scale with around 450 people involved.

But the latest planned overhaul looks set to dwarf those projects.

And the fact that the water supply must be maintained at all costs means closing off the flow is not an option, making the project extremely challenging from an engineering standpoint.

“It’s a massive undertaking,” said United Utilities’ director of strategic programmes Neil Gillespie

“Although we have an initial design, we’re also talking to construction firms and financial institutions to assess the options for how the scheme could be built and financed.”

A United Utilities spokesperson said the project was of such a huge scale that at this stage it was difficult to go into any detail with regard to any disruption the work may cause, though it was hoped it would be minimal.

The spokesperson confirmed that geotechnical and environmental surveys were getting under way along the route of the pipeline, from Kendal to Manchester, to help the water company firm up its design for the work to come.

However, initial work has been proceeding in the Kendal area for some time without any major problems, though some minor road closures have resulted during survey work due to safety considerations.

“This section near Kendal will take us until late 2020 to complete, and then we will be reinstating the fields until the following year,” said construction manager John Dawson.

“We will be installing more than 800 pieces of pipe, each up to 14m long and 1.6m across. We started laying the pipes in April and already 170 sections are in the ground.”

The main construction project is scheduled to begin in 2023 and will take around 10 years to complete.