Sir David hopes to find new ways to cut congestion
An inquiry has started to examine the reasons behind major congestion on the A12 in Essex.
The study by the county council is thought to be the first of its kind to be held by a local authority into a major trunk route.
It is to be led by Sir David Rowlands, a former Permanent Secretary at the Department for Transport.
The council estimates traffic problems and delays on the A12 cost the county's economy about £250m a year.
The A12 is owned and operated by the Highways Agency and runs for 121 miles (195km) between London and East Anglia.
The inquiry will review the present and likely future performance of the A12.
It will look at ways of cutting congestion levels, taking evidence from those responsible for the running of the road and clearing accidents.
Sir David said: "This inquiry is a first of its kind in the UK and I commend Essex County Council for commissioning it to find a way this major trunk route can better serve its residents.
"I will now carry out a thorough investigation of the A12 with a view to recommending a way forward to relieve congestion in the future."
County council leader Lord Hanningfield said: "This inquiry has never been more timely with more than 40,000 homes due to be built along the corridor and the rapid expansion of two of Britain's biggest ports nearby putting the road under more pressure than ever."
The inquiry closing date for written evidence and comments from the public will be on 19 May and the final report will be released in July.