Highways England staff will be carrying out preliminary work over the next two months along the line of the proposed A585 upgrade work.
From June 17, staff will be carrying out ground investigations to help engineers understand the conditions on land near to the controversial road between Windy Harbour and Skippool.
It will also assess the nature of any archaeological features below the ground.
A spokesman said: “We expect this work to take approximately eight weeks.
“Site access and deliveries will be required at each area and will be managed with temporary traffic management – using either temporary lights or ‘stop’ and ‘go’ boards. Working hours for the team will be from 8am to 5pm Monday to Friday.”
The Planning Inspectorate is currently examining the application for the three mile by-pass dual carriageway.
Last month, Lancashire County Council highways officers submitted their own assessment of the scheme as part of the process to secure planning permission for the three-mile dual carriageway route.
They had concerns over potential traffic levels on other parts of the road network in the area if the bypass is built such as at Garstang Road East and Thistleton crossroads.