There are now calls for the road to be returned to the taxpayer, with toll fees slashed.
Public ownership?Owned by Midland Expressway via parent company Macquarie Atlas Roads, Britain's first pay-as-you-go highway - the toll costs £5.50 for private cars and £11 for trucks - could even be renationalised, some are urging.
"If the M6 Toll cannot be made to work in terms of attracting more vehicles off the M6 then one solution is to take it into public ownership," Geoff Inskip, boss of Centro, the West Midlands transport authority, told the Independent.
"This would give us the option of setting a level of charge that does encourage through traffic," he adds. Macquarie Atlas is lumbered with the M6 Tollway concession until 2054. Most toll roads in the UK are constructed to deal with open stretches of water and bridges - but not the M6.
And why would anyone pay to use the M6 when traffic congestion is okay, helped in part by better up-to-date information from a satnav or other device? The Campaign for Better Transport claims traffic on the M6 has returned to pre-toll levels and most journeys are only marginally quicker than in 2003.
"Bad choice for motorists"
The news of the M6 failure comes at a sensitive time for the Government, torn over how to finance new UK road-building. For example, the Treasury is thought to be considering pushing ahead with a new M4 toll relief road in South Wales - but the Welsh Government has branded the idea unworkable.
Such a move could cost the Welsh Government £850m, reliant on repaying the cash with toll fees. Going on the M6 experience, that's going to be difficult. It also contrasts with the Scottish experience - there will be no new tolls for the new Forth Bridge.
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