A trial run begins today to see if the River Ouse could be used to transport sewage sludge.

Anglian Water uses tanker lorries to transport waste to its treatment works at Clenchwarton, near King's Lynn.

But officials believe barges could do the job instead – cuttting the number of lorries on roads around the plant, in Clockcase Lane.

Powerful tugs will leave Cathedral Marina in Ely this morning, towing a large pontoon.

Over the next two days, they will travel down the river, via Queen Adelaide and Littleport, until they reach the tidal Ouse at Denver Sluice.

The flotilla will then enter the tidal river, via Denver Lock, tomorrow afternoon, before continuing down-stream to King's Lynn. On reaching Lynn, tomorrow evening, the pontoon and tugs will moor up at Boal Quay.

Anglian water spokesman Ciaran Nelson said the company was serious about its plans and would be consulting river users about them.

'One of the issues we face with this as a potential solution to the number of tankers on the roads is there are so many consultees,' he said.

He added it was hoped that the trial run would answer some of river users' questions about the company's proposals.

Consultees include marinas, the Environment Agency and the Port of King's Lynn.

Anglian Water hopes shipments could begin by 2015 if the trials are successful. The firm will also need to carry out some alterations to its works at Ely and Clenchwarton, to enable the sludge to be pumped out to the barges.

Sludge is a by-product of the sewage treatment process, which is turned into biogas and fertiliser.

Up to 60 lorries a day deliver it to the works at Clenchwarton – which is also near the river, meaning sludge could also be brought to Lynn by water.

Barges and sailing vessels called lighters were used to carry freight inland from King's Lynn before the coming of the railways.

They were also used to transport sugar beet to the former factory on the river near Ely, and loads of gault from Roswell Pits to strengthen the Ouse floodbanks.