The Chancellor's autumn statement earlier this month contained lots of proposals to boost spending on infrastructure but, not surprisingly, canals did not feature highly.

One man thinks it should have. David Weight, associate director at engineering consultants Aecom, has proposed a multi-purpose canal stretching from the Scottish border to the outskirts of London. The waterway could provide a number of sustainability services right along its length.

The main one would be transporting water from the north to the south. The south east of England is both one of the driest and the most populous region in the UK, while eastern England is even drier and its agriculture sector requires lots of water for irrigation. By 2030, the UK needs to produce 50% more food than it does today, according to the government, and we will need 30% more fresh water. In the longer term, the canal could be extended north of the border to give access to Scottish water as well.

"This is a concept that should be looked at seriously," added Paul Hammett, national water specialist at the National Farmers Union. "In the long term, we have a real challenge in finding enough water to be able to continue to grow our food."

The idea is not new – in 1942 JF Pownall proposed a Grand Contour Canal that would use gravity to transport water from one end of the country to the other, avoiding the need to use expensive and energy-intensive pumping equipment.

Transporting water without the need for pumping is one of the key features of Weight's scheme, and he claims the canal would be more efficient and more resilient than smaller-scale, piecemeal water transfer projects..

Weight acknowledged "there could be major problems with obstruction, crossings and planning," but pointed out that the canal could be used for a number of other purposes, ranging from flood relief to tourism. These include putting a high voltage cable underneath the canal to transport another of Scotland's plentiful resources – renewable energy – to the south east's centres of demand. As well as saving money by providing an alternative to undersea cables, it would also make the cables secure against metal thefts, allow them to be water-cooled, avoid having to put them in the corrosive marine environment and keep the cables out of sight while still having easy access to them, Weight asserted.

The canal could also carry data cables, which would allow data centres to be sited in Scotland where they could make use of the country's wind and hydro-electric power, as well as having to spend less on power to keep their servers cool because of the lower temperatures at higher latitudes.

And with Drax, Britain's largest power station, planning to convert three of its coal-fired generating units to run on biomass, the canal can help there, too. "It would be ideal for transporting biomass from northern Scotland, where there is a big afforestation programme, to Drax, Eggborough and Ratcliffe on Soar power stations, helping them to cut their emissions," Weight said.

The waterway could also act as a conduit for district heating, using waste heat from those same power stations and it could even help to reduce flooding by acting as a run-off in times of heavy rainfall, said Christopher Cook, senior research fellow of the Institute for Security and Resilience at University College London.

The canal remains a proposal at the moment, and a number of further studies are needed to establish the various business cases. The scheme would certainly not be cheap – Aecom estimates that a 10m-15m-wide canal would cost somewhere between £12bn and £20bn. "Funding is a big challenge," said Simon Bamford, head of water at the Canal and River Trust. "And of course, this is something that would cut through communities and the countryside."

We have already seen the opposition to large-scale projects with the HS2 rail scheme, but Cook believes that a canal scheme could face less opposition. "People do not want to live next to HS2, Runway 3 (at Heathrow) or the M99, but they do want to live next to water." The canal would provide tourism and recreation benefits as well as acting as a haven for wildlife and biodiversity. And while one of the reasons people oppose HS2 is the threat of a fall in house prices, a canal, by contrast, may lift land values, Weight said.

The plan may not need public funding because of the number of different services it could provide. However, given the wide range of different organisations that could be involved, including water companies, transmission operators, data centres, forestry companies and a whole slew of local authorities, it would need government support to make it happen.

However, not everyone is in favour. "The fundamental problem this idea seeks to address is valid – the south east and eastern England face growing populations and a changing climate that will put pressure on water resources," said Ciaran Nelson, head of communications at Anglian Water. "But that is not a problem that is restricted to just those regions."

In recent years, the north west of England and Scotland have experienced their own water shortages, he pointed out. "It also overlooks the existing interconnectivity that exists within and between different regions. We would do much better to improve connectivity between water companies – it would be far more cost-effective and easy to implement."

Nonetheless, the government is cautiously encouraging of the plan. A spokesperson for the Environment Agency said: "We are also always pleased to see other organisations highlighting new thinking and stimulating innovation into the water sector." However, it warned: "Water is heavy and costly to move across long distances, and transferring water through canals and rivers can cause damage to the environment so proposals for new transfers need careful consideration."

"Of course, it is not without its challenges," said Bamford, "but if no-one came up with these ideas then nothing would ever happen."

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