Row over TfL's £18m Coulsdon bypass

Only five of the six shortlisted contractors have returned tenders for the £18m Coulsdon bypass in south London, according to client Transport for London (TfL). Confusingly, all six firms pitching for the scheme insist they have returned bids.

But CJ understands one firm - believed to be Alfred McAlpine - has pulled out of the tender process because of a row over box-jacking techniques.

Sources say the company has quit the race because of the client's tight specifications relating to the single-span box structure, which will allow the new road to pass under Smitham railway station.

An insider claimed: "The firm was worried that TfL's specifications on space, technique and hydraulics suggested only one method - the patent of another rival bidder - could be used."

It is understood that TfL specified the John Ropkins method - most recently used by Edmund Nuttall on a £6m scheme at junction 15A of the M1.

There is speculation that the client's strictures have resulted in only one conforming bid from the five bidders now left in the race.

But a TfL source claimed: "None of the five has been disqualified because of a non-conforming tender. Let's say that all the bids conform in different ways - we are looking at alternatives as well."

TfL is still running the rule over the five remaining pitches. Balfour Beatty, Costain, Nuttall, Skanska, Hochtief and Alfred McAlpine are the six hopefuls originally selected to bid for the job.