Cornwall's motorists will have 21 road closures to avoid nearby on the National Highways network this week.

And three of them are expected to cause delays of between 10 minutes and half an hour.

The latest expected works list, with notes from National Highways, shows that five closures already in place are expected to carry on this week:

• A30, from 8pm September 25 to 5am October 30, slight delays (under 10 minutes): A30 between Carland Cross and Mitchell traffic signals for Chiverton to Carland improvement scheme.

• A30, from 8pm October 23 to 6am October 30, slight delays (under 10 minutes): A30 Chiverton Cross roundabout lane closure for Chiverton to Carland improvement scheme.

• A38, from 7pm October 25 to 6am November 4, slight delays (under 10 minutes): A38 both directions Saltash Tunnel to Carkeel Roundabout carriageway closed for sign erection works. Diversion via the B3271.

• A30, from 4am September 23 2023 to 6am March 23 2024, slight delays (under 10 minutes): A30 both directions Carland Cross to Mitchell contraflow for Chiverton to Carland improvement scheme. Variable speed restrictions.

• A30, from midnight, September 1 2020 to 6am March 28 2024, slight delays (under 10 minutes): A30 Carland Cross to Chiverton Cross improvement scheme.

And a further 16 closures will begin over the next two weeks:

• A30, from 7pm October 30 to 6am November 3, slight delays (under 10 minutes): A30 both directions Chiverton Cross to Carland Cross carriageway closures for Chiverton to Carland improvement scheme, westbound, diversion via A3058 from Summercourt, A392 and A3075 to Chiverton Cross. Reverse for eastbound.

• A30, from 7pm October 30 to 6am October 31, slight delays (under 10 minutes): A30 both directions St Erth to Canonstown - two-way signals for carriageway reconstruction/renewal works.

• A30, from 10pm October 30 to 5am October 31, slight delays (under 10 minutes): A30 both directions Avers to Scorrier - lane closures for safety barrier repair.

• A30, from midnight, October 31 to 5am November 13, slight delays (under 10 minutes): A38 Plymouth to Bodmin and A30 Bodmin to Penzance used by GWR Railway Replacement Buses for Plymouth to Penzance route.

• A30, from 9.30am October 31 to 3.30pm November 2, slight delays (under 10 minutes): A30 eastbound, Kennards House lane closure for BT works.

• A38, from 8pm November 1 to 4am November 2, slight delays (under 10 minutes): A38 westbound, Menheniot lane closure for barrier repairs.

• A30, from 9pm November 1 to 5am November 2, moderate delays (10-30 minutes): A30 westbound, Callywith to Carminow Cross carriageway closure for electrical works, diversion via A38 to Turfdown Roundabout, u-turn back to A30.

• A30, from 8pm November 2 to 6am November 3, slight delays (under 10 minutes): A30 Newtown roundabout to Varfell traffic signals for road markings.

• A30, from 8pm November 2 to 6am November 3, slight delays (under 10 minutes): A30 westbound, Five Lanes, lane closure for barrier repairs.

• A30, from 8pm November 3 to 6am November 6, slight delays (under 10 minutes): A30 both directions Chiverton Cross to Boxheater (B3285) weekend carriageway closure for improvement scheme, diversion via A3075 and B3285.

• A38, from 7pm November 6 to 6am November 10, slight delays (under 10 minutes): A38 both directions Saltash Tunnel to Carkeel Roundabout carriageway closed for sign erection works. Diversion via the B3271.

• A30, from 8pm November 6 to 6am November 9, moderate delays (10-30 minutes): A30 westbound, Highgate to Mitchell carriageway closure and convoy working for road markings, diversion via A39, A392, A3058 and A3076.

• A30, from 9pm November 7 to 6am November 8, slight delays (under 10 minutes): A30 both directions Hayle Bypass carriageway closure for surveys, diversion via B3301 through Hayle.

• A30, from 8pm November 9 to 6am November 11, moderate delays (10-30 minutes): A30 eastbound, Mitchell to Highgate carriageway closure for road markings, diversion via A3076, A3058, A392 and A39.

• A30, from 7pm November 13 to 6am November 14, slight delays (under 10 minutes): A30 eastbound, Mitchell two-way slip road traffic signals for Cornwall Council works.

• A38, from 8.30pm November 13 to 6am November 18, slight delays (under 10 minutes): A38 both directions Dobwalls to Turfdown carriageway closed for routine maintenance. Diversion via A390, B3269, B3268 and Turfdown Road.

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