The Highways England programme includes the construction of new storm drains as well as resurfacing and new road markings, including 550 new studs.
The work is expected to be completed by the end of April subject to suitable weather conditions, with a break between 24 and 29 March to minimise disruption at Easter.
Temporary traffic lights will operate 24 hours a day for the safety of crews and drivers.
Full road closures in both directions will also be required on some nights between 8pm and 6am, and at some weekends.
Project manager Peter Gee said:
Drivers should notice a significant improvement in the road conditions here when work is completed. In the meantime we aim to get the work done within a tight timescale and keep disruption to a minimum.
When the road is closed, diversions for HGVs and other vehicles will be clearly signed. Drivers are advised to use the A591 and the A595. This route is not suitable for HGVs which should use the M6 and A595.
Dates of closures will be announced nearer the time.
Members of the public should contact the Highways England customer contact centre on 0300 123 5000.
Journalists should contact the Highways England press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.