The firm would not identify its problem project but the Enquirer understands it is suffering major cost overruns on the Liverpool 2 container port development for Peel Ports.
A BAM/Van Oord joint venture won a £75m deal to help deliver the £300m terminal expansion at Seaforth two years ago.
BAM’s work involves constructing a 854m quay wall against a 10m tidal range, and installing ship to shore quay crane rails and supporting infrastructure.
The full extent of the firm’s woes on the on-going job were unveiled in latest accounts lodged at Companies House yesterday.
Chief executive Stephen Fox said benefits from group-wide measures to reduce risk in the business and be more selective about tenders had been sunk by the project.
Fox said: “Our increased scrutiny and selectivity of tendering and contract management has resulted in a strengthened performance across the business.
“However this good work has been offset by one extremely challenging contract, which has resulted in a significant loss for the company.”
He added: “The directors are deeply disappointed at having to report this and the project in question has obviously drawn a significant amount of management time.
“We now have this under control and during 2015, this contract will be substantially completed.”
He said that BAM Nuttall’s cash position had also been affected by the job but BAM had maintained liquidity of over £100m at the end of financial year.
In the year to December 2014, the firm’s turnover edged up 2% to £774m.
Fox said: “Elsewhere we have remained busy, with revenues growing and with our order book becoming less dependent on London and the South East.”