Drivers in and around Cornwall will have 23 National Highways road closures to watch out for 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 four closures already in place are expected to carry on this week:

• A30, from 8pm June 23 to 6am August 2, moderate delays (10-30 minutes): A30 eastbound, Temple Tor to Bolventor - lane closure and convoy for carriageway resurfacing works. Westbound, central gap closure near Temple, diversion via A30 westbound to Temple Tor, junction and return.

• A38, from 8pm February 25 to 6am August 9, slight delays (under 10 minutes): A38 westbound, Saltash Tunnel to Carkeel Roundabout -carriageway closed for sign erection works, diversion via B3271.

• A38, from 7pm June 11 to 6am August 16, slight delays (under 10 minutes): A38 eastbound, Carkeel roundabout to Saltash Tunnel carriageway closed for sign erection works. Diversion via the B3271.

• A38, from 6am January 14 to 8pm September 19, slight delays (under 10 minutes): A38 eastbound, Carkeel roundabout to Saltash Tunnel - narrow lanes including 30mph speed restriction and layby closures for sign erection works.

And a further 19 closures will begin over the next two weeks:

• A30, from 8pm July 14 to 6am July 26, moderate delays (10-30 minutes): A30 eastbound, Chiverton to Carland - carriageway closure for Chiverton to Carland improvement scheme, diversion via A3075, B3285, B3288, re-join A30.

• A30, from 8pm July 14 to 6am July 19, slight delays (under 10 minutes): A30 westbound, Bolventor to Temple - lane closure for carriageway resurfacing works.

• A30, from 9am July 15 to 4pm July 17, slight delays (under 10 minutes): A30 both directions Longrock Bypass - lane closure for survey works.

• A30, from 7pm July 15 to 6am July 16, slight delays (under 10 minutes): A30 westbound, Mitchel exit and entry slip road closed for white lining, diversion for exit slip westbound to Carland Cross and return, diversion for entry slip eastbound to Fraddon and return.

• A30, from 7pm July 15 to 6am July 16, slight delays (under 10 minutes): A30 westbound, Victoria exit slip road closed for white lining, diversion westbound to Highgate and return.

• A38, from 7pm July 15 to 6am July 16, slight delays (under 10 minutes): A38 Bodmin to Liskeard, traffic lights for structure inspection.

• A30, from 7pm July 18 to 6am July 19, slight delays (under 10 minutes): A30 eastbound, Cannaframe exit and entry slip roads closed for white lining, diversion for exit slip road eastbound to Five Lanes and return, diversion for entry slip road westbound to Bolventor and return.

• A30, from 7pm July 22 to 6am July 23, slight delays (under 10 minutes): A30 westbound, Highgate exit slip road closed for white lining, diversion westbound to Fraddon and return.

• A38, from 7pm to 11.59pm on July 22, slight delays (under 10 minutes): A38 Glynn Mill House, traffic lights for BT.

• A38, from 8pm July 22 to 6am July 25, slight delays (under 10 minutes): A38 Both directions Tideford to Landrake two-way signals for electrical works.

• A30, from 8pm July 22 to 6am July 24, slight delays (under 10 minutes): A30 both directions Loggans Moor to St Erth two-way signals for electrical works.

• A30, from 7pm July 23 to 6am July 25, slight delays (under 10 minutes): A30 Both Directions Crowlas to St Erth multi way signals for white lining.

• A38, from 8pm July 23 to 6am July 25, slight delays (under 10 minutes): A38 eastbound, Moorswater exit slip road closure for inspection/survey, diversion to Liskeard and Return.

• A30, from 7pm July 24 to 6am July 25, slight delays (under 10 minutes): A30 westbound, Lewannick to Five Lanes - lane closure and convoy working for white lining.

• A30, from 7pm July 25 to 6am July 27, slight delays (under 10 minutes): A30 Both Directions Longrock to Crowlas multi way signals for white lining.

• A30, from 8pm July 25 to 6am July 26, moderate delays (10-30 minutes): A30 eastbound, Carminow Cross exit slip road closed for carriageway resurfacing works. Diversion via A30 eastbound to Cardinham and return to exit at Callywith.

• A30, from 7pm July 28 to 6am August 28, slight delays (under 10 minutes): A30 both directions Loggans Moor to Treswithian carriageway closed for resurfacing. Diversion via Connor Downs.

• A30, from 7pm July 28 to 6am July 31, slight delays (under 10 minutes): A30 both directions St Erth to Canon's Town traffic signals for Wildanet works.

• A30, from 10pm July 28 to 6am July 30, slight delays (under 10 minutes): A30 westbound, Highgate Hill exit and entry slip roads closed for Virgin Media works. Exit slip diversion via A30 westbound to Fraddon and return to exit. Entry slip diversion via A30 eastbound to Victoria and return.

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