The commission was called in to investigate following complaints from council staff over how the contract was awarded in 2008.

A report published today criticises the council for how the tender process was handled and makes a series of recommendations to improve future procurement.

The report highlights how the council’s director of technical services met with Colas in the pre-tender period and how he failed to declare a personal relationship with a Colas representative until after the contract award.

The commission also found that Colas quoted a rate for electrical work which was 1/50th that of rival bidders.

The Colas bid involved electrical subcontractors being paid directly by the council which would have added an extra £1.495m to the winning price.

The report stated: “The estimated additional £1.495m would not have increased the tender price above that of the next lowest tenderer.

“However, the subsequent variation to the rates for electrical works casts doubt on the robustness of the tender evaluation process.

“Officers have accepted that procedures need to be amended for future contracts in this respect.

“In addition, there is evidence that the contractor has from the inception of the contract struggled to secure a financial return on the contract.

“Information provided to me, and an external independent review report in June 2010, confirmed that this was the case.

“This calls into question the effectiveness of the council’s assessment of unusually low rates.”

For a copy of the full report click here