The M65 has reopened after an overnight closure overran by four hours this morning (November 29).
The westbound M65 was shut overnight between junctions 4 (Darwen, A666) and junction 3 (Blackburn, A674) due to resurfacing works.
Highways said the closure was due to be lifted by 6am, but due to "unforeseen circumstances", it remained closed until 10am.
It has since confirmed that resurfacing works overran "partly because of a dip in temperatures".
The lengthy closure forced commuters to be diverted during peak morning rush hour, causing delays of up to an hour.
But at 10am, Highways confirmed that the M65 has fully reopened. But the agency is warning of 'residual delays' due to ongoing congestion between junctions 6 and 3.
Highways England said it is currently investigating why the works were not completed on time.
A spokesman for Highways England said: "During overnight resurfacing last night and into this morning we weren’t able to complete the work and re-open the carriageway at 6am as planned.
"This was due to an unexpected shortfall in the amount of resurfacing material delivered to the site in rolling deliveries.
"As soon as this was discovered, we worked hard to ensure the likely over-run of the work was communicated to drivers throughout the morning using social media and bulletins to travel media.
"We are investigating exactly what went wrong to ensure this doesn’t happen again.
"We would like to apologise to anyone affected by the carriageway closure and also thank them for their patience while we arranged to finish the work."
The agency is asking anyone wishing to make a complaint to call 0300 123 5000 or email firstname.lastname@example.org