The Enquirer understands that Balfour Beatty, Vinci and VolkerFitzpatrick will shortly be receiving tender documents for the Ilford yard stabling project.
A winner will be announced next summer for the 38-month construction programme.
Work will involve building new berths for Crossrail trains of more than 200 metres in length.
A variety of maintenance buildings will also be erected as part of the transformation of the 12 hectare site.