An independent report carried out into defects on the guided busway has supported Cambridgeshire County Council’s claim that the contractor, BAM Nuttall, is responsible and should pay for repairs.

The guided buswayThe guided busway

Members of the county council's general purposes committee will meet on November 29 to look at the independent engineer's report into the findings of investigations carried out jointly for the authority and BAM Nuttall.

The report, carried out by Capita, concludes that the defects represent a breach of contract by the contractor who designed and built the busway, and noted that additional defects could also require repair.

The paper to be put before councillors recommends that the defects should be rectified with initial costs for the work at £36.5 million and this, as well as legal costs, should be picked up by BAM Nuttall.

Councillors on the committee are being asked to agree that the defects are rectified as part of one programme rather than on a piecemeal basis as they deteriorate, which, it is estimated, would cost considerably more in the long run and cause more disruption to services.

Councillors are being asked to support a dual approach of seeking, if possible, to negotiate with BAM Nuttall while also starting legal proceedings.

The council believes the works could be carried out in sections to allow other parts of the busway to remain open while the defects are rectified.

According to the engineer's report, the principal defects include:

- Vertical and horizontal steps have developed at the joints between the precast track sections or 'ladders'

- The foundations of the guideway are moving differentially; and

- The concrete of the guideway is spalling (slivers of concrete breaking off corners) in numerous locations

Adrian Savory, operations director for BAM Nuttall, said: "I am really surprised that the council hasn't come to talk to us before publishing this latest report.

"BAM Nuttall is totally committed to ensuring that the busway performs as it should. If there is anything wrong with the busway for which BAM Nuttall is responsible, BAM Nuttall will put it right.

"We've told the council this many times and invited them to come to us to explain the basis for their concerns. BAM Nuttall would welcome the opportunity to discuss the latest report with the council."

The report comes following a lengthy legal dispute between the county council and BAM Nuttall which ended in 2013 with the latter agreeing to pay back £33million of the £147.7million project costs.

The parties had argued over who would be responsible for an overspend for the busway route between St Ives and Cambridge.

The initial contract was for 130 weeks of work, with the completion date on February 27, 2009, but the busway construction was not completed until April, 2011, and not open for use until August of that year as the county council raised concerns about defects.