Drivers in and around the Forest of Dean will have eight National Highways road closures to watch out for this week.

And one of them is expected to cause major delays – with motorists facing a holdup of at least 30 minutes. Another four will cause moderate delays of between 10 minutes and half an hour.

The latest expected works list, with notes from National Highways, shows that eight closures are due to start over the next two weeks:

• A40, from 9am November 27 to 4pm December 15, slight delays (under 10 minutes): A40 both directions Huntley. 2-way signals for private residence boundary wall repair.

• M48, from 7pm December 4 to 6am December 6, moderate delays (10-30 minutes): M48 eastbound, junction 2 to 1 Severn Bridge - carriageway closure for structure maintenance. Diversion via M4 Prince of Wales Bridge.

• M48, from 7pm December 4 to 6am December 6, slight delays (under 10 minutes): M48 westbound, junction 1 to 2 Severn Bridge lane closure for structure maintenance works.

• M50, from 9pm December 4 to 6am December 5, moderate delays (10-30 minutes): M50 eastbound, jct four to 2, carriageway closure for barrier safety repairs, diversion via local authority network.

• M48, from 7pm December 6 to 6am December 8, slight delays (under 10 minutes): M48 eastbound, junction 2 to 1 Severn Bridge - lane closure for structure maintenance.

• M48, from 7pm December 6 to 6am December 8, moderate delays (10-30 minutes): M48 westbound, junction 1 to 2 Severn Bridge carriageway closed for structure maintenance works. Diversion via M4 Prince of Wales Bridge.

• A40, from 9pm December 11 to 6am December 14, moderate delays (10-30 minutes): A40 eastbound and westbound, Marstow to Wilton roundabout, carriageway and lane closure due to resurfacing works, diversion via local authority Network.

• A40, from 10pm December 11 to 6am December 13, severe delays (more than 30 minutes): A40 eastbound and westbound, Lea to Huntley carriageway closures for maintenance, Light vehicle diversion via local road to Mitcheldean and A4316, HGV diversion via A40, A449, M50 and A417.

National Highways is responsible for maintaining motorways and major A-roads, so closures of smaller roads will not be included in their schedule.