Interestingly enough the BBC suggests that Westminster sources have confirmed that an agreement in principle had been reached but a deal on funding was not finalised. Considering that when the Welsh Government looked at this option it was binned on grounds of cost. One of the reason why, when Plaid was in government (between 2007 and 2011) that the M4 Gwent Levels relief road was dropped was that it was unaffordable.
During the botched consultation in the spring of 2012, the one option that made the most sense was the one that would have involved the grade separation of some junctions and partial or full closure of other junctions on the Newport A48 Southern Distributor Road (SDR) which should be a real alternative route to the M4. Price wise that would have come in at around £300m, this would be more affordable that the £ 1 billion pounds plus that any Gwent Levels M4 relief road would cost.
Plaid Cymru Economy and Transport spokesperson Jonathan Edwards MP said:
"Plaid Cymru when in government looked afresh at the needs of the M4 and Wales-England transport corridor under Ieuan Wyn Jones. This included the principle of tolling, which we rejected. We embarked on a programme of improvements, including the Newport distributor road and the rail electrification, which could alleviate congestion and meet both business and environmental objectives. These need to be fully rolled out as an alternative to a highly expensive, environmentally damaging brand new motorway. The proposal that such a motorway would be tolled in Wales is the worst of all scenarios as we need to attract business investment not put it off with a penalty charge for coming to Wales.
“Wales has a real need for useful infrastructure spending, linking all parts of our nation and increasing connectivity. Rather than tolls, what's needed is a swift implementation of the Silk recommendations and a Barnett floor so we can borrow effectively and efficiently to invest.
“But does anyone seriously think that charging motorists to cross the Severn Bridge and then charging them again to use the motorway a few miles later is going to make south Wales more economically competitive?
“The only other toll road in the UK is the M6 in the Midlands which has seen toll prices rise by 175% since it was opened but the number of users plummet. It has also done nothing to reduce congestion. The lack of any other toll road proposals shows what people think.
“Wales has a greater capacity for borrowing money because we don’t have as many debts due to PFI, but we have to make sure that this is invested in schemes which will pay their way both in the short and longer term for the economy and sustainability."
The Party of Wales former Transport Minister Ieuan Wyn Jones said:
“The reason that the M4 relief road was abandoned was not simply the issue of affordability at £1 billion but also the fact that I was advised that not only was the new relief road to be subjected to tolls, so was the existing M4 to be tolled. This was due to the evidence that had been gained during the operation of the M6 toll road which had never made any money. I came to the conclusion that it was simply unacceptable for motorists to have to pay tolls on the Severn bridges and on the existing M4 and new relief road. There was already significant complaints about the tolls on the Severn bridges and this additional burden on motorists and businesses could not possibly be justified. That is why I accepted my officials’ advice not to proceed with the relief road but to ease congestion around Newport by linking into the southern distribution road as an alternative route.”