Roadworks are planned for vital transport routes in Hertfordshire next week, the Highways Agency has revealed.

Welwyn Hatfield Times: Hatfield TunnelHatfield Tunnel (Image: Archant)

The M1 Junction 6a will be closed for electrical work at the southbound link road to the clockwise M25, between 10pm and 5am, on Monday, October 20.

A clearly signed diversion route will be in place via the M25 junction 20.

M25 Junctions 25 to 27 will be speed limited for “major improvement” works to take place.

Narrow lanes and a 50mph speed limit will be in place on both carriageways between Junctions 25 and 27, with a free recovery service operating 24 hours a day.

There will be additional lane and slip road closures required.

The clockwise entry slip road at Junction 25 will be closed overnight, between 10pm and 5.30am, for two nights from Friday 24 October.

Work on Friday night will start at 11pm.

A clearly signed diversion route will be in place via junction 24.

The clockwise exit slip road at junction 26 will be closed overnight, between 10pm and 5.30am, for three nights from Monday 20 October. A clearly signed diversion route will be in place via junction 28.

On the A1(M) Junctions 4 to 2 (Hatfield Tunnel), will close for a road survey.

The southbound carriageway will be closed overnight, between 10pm and 5am, for three nights from Tuesday, October 21.

A diversion route will be in place via the A1001.

A1(M) Junction 4 will have “carriageway sweeping” taking place.

The northbound exit slip road will be closed overnight, between 10pm and 5am, on Monday, October 20.

A diversion route will be in place via Junction 6.

A spokesman said: “The Highways Agency is working with the industry and road users to reduce the risks of working on the roads.

“For the safety of road workers and all road users, when you are approaching roadworks keep within the speed limit – it is there for your safety.

“Get into the correct lane in good time – don’t keep switching.

“Concentrate on the road ahead, not the roadworks.

“Be alert for works’ traffic leaving or entering roadworks.

“Keep a safe distance – there could be queues in front.

“Observe all signs – they are there to help you.”