North Somerset's motorists will have seven road closures to avoid nearby on the National Highways network this week.

And two of them are expected to cause severe delays – with drivers facing waits of at least 30 minutes. Another two will cause moderate delays of between 10 minutes and half an hour.

The latest expected works list, with notes from National Highways, shows that one closure already in place is expected to carry on this week:

• M5, from 4pm July 30 to 5pm September 30, slight delays (under 10 minutes): M5 northbound, junction 21 exit slip - two-way signals for electrical works.

And a further six closures will begin over the next two weeks:

• M5, from 9pm August 26 to 6am August 30, slight delays (under 10 minutes): M5 northbound, junction 19 to junction 18 lane closures for bridge maintenance.

• M5, from 8pm August 28 to 6am August 30, moderate delays (10-30 minutes): M5 southbound, junction 21 exit slip road closure for resurfacing, diversion southbound to junction 22 and return.

• M5, from 10pm September 2 to 5am September 3, slight delays (under 10 minutes): M5 northbound, junction 21 - carriageway closed between the exit and entry slip roads to facilitate diversion for M5 northbound, junction 19 to 18 Avonmouth Bridge closure, diversion for traffic wanting to travel to junction 18 or further north to follow A370 eastbound, A4 Portway, re-join M5 northbound, at, junction 18, Access to junction 20, junction 19 and Royal Portbury Dock ONLY to re-join M5 immediately.

• A4, from 10pm September 2 to 5am September 3, severe delays (more than 30 minutes): M5 southbound, junction 18 to 19 Avonmouth Bridge carriageway closure for inspections, diversion southbound, via A4 Portway, A370, A38 re-join M5 at, junction 22, southbound, traffic to junction 19 Royal Portbury Docks diversion via A4, A370, B3128, B3129, A369 to junction 19.

• A4, from 10pm September 2 to 5am September 3, severe delays (more than 30 minutes): M5 northbound, junction 19 to 18 - carriageway closure for inspections, diversion via exit M5 at, junction 21, A370, A4 Portway, re-join M5 at J18. Access to junction 20, junction 19 and Royal Portbury Dock ONLY remain on M5.

• M5, from 9pm September 8 to 6am September 9, moderate delays (10-30 minutes): M5 southbound, junction 20 exit slip road closure for drainage, diversion southbound to junction 21 and return to junction 20.

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