Relocation of Roman snails held up work on the £30m bypass and flood alleviation scheme.
The project will serve residents of the new 750-home Bishop's Stortford South estate, St James' Park.
The stretch between the Tesco and Stansted Road roundabouts will be closed for several days and traffic diverted through the town centre.
The incident happened on the northbound carriageway between junctions 6 (M25) and 7 (Harlow).
Essex Highways is due to meet a landowner on site to discuss ditch clearance to prevent further flooding of the main B1383.
Residents say flooded B1383 closure is down to poor maintenance of blocked drains and not the River Cam bursting its banks, as county council says.
Week-night work to renew lighting to begin Monday December 14 and end in mid-April, with a break over Christmas and New Year.
The measures are part of a drive to make travel safer over the festive period as families take advantage of an easing of Covid-19 restrictions.
The spur roads at junctions 9 and 9a will be shut from Friday evening to Monday morning for vital repairs to carriageway surface.
Contractors will be carrying out remedial works and resurfacing between the Stansted Road and Tesco roundabouts this weekend.
Opponents describe restrictions as “buffoonery” – Cllr Woodward says joining in formal consultation is more effective than venting on social media.
Vehicles blocking paths were in the top five of people’s complaints to Herts county councillor Eric Buckmaster.
Villagers with placards line A1060 to draw attention to speeding motorists and to call for speed cameras to be installed.
County council has shut South Street to through traffic, imposed one-way system in Newtown Road and closed Apton Road junction with Potter Street.
Herts County Council scheme would bring in restrictions including 20mph limits in south-east quadrant of Sawbridgeworth.