Cornwall's motorists will have 19 road closures to avoid nearby on the National Highways network this week.

And two of them are expected to cause moderate delays – with drivers facing waits 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 15 closures will begin over the next two weeks:

• A30, from 7pm July 7 to 6am July 8, slight delays (under 10 minutes): A30 eastbound, Mitchel and Summercourt entry and exit slip roads closed for white lining, diversion for entry slip roads westbound to Carland Cross and return, diversion for exit slip roads eastbound to Fraddon and return.

• A30, from 7pm July 7 to 6am July 8, slight delays (under 10 minutes): A30 westbound, Cannaframe exit and entry slip road closure for carriageway resurfacing, exit slip diversion via - A30 westbound to Bolventor, junction and return eastbound and exit at Cannaframe junction, entry slip diversion via - A30 eastbound to Trewint and Rejoin A30 westbound, at Fivelanes junction.

• A38, from 7pm July 7 to 4am July 8, slight delays (under 10 minutes): A38, both directions, Tideford West End - 2-way signals for the carriageway - reconstruction/renewal.

• A30, from 8pm July 7 to 6am July 12, slight delays (under 10 minutes): A30 eastbound, Fraddon to Highgate, lane closure for electrical works.

• A38, from 8pm July 7 to 6am July 9, slight delays (under 10 minutes): A38 eastbound, Dobwalls, lane closure for barrier works.

• A30, from 8pm July 7 to 6am July 8, slight delays (under 10 minutes): A30 eastbound, Avers exit slip road lane closure for BT works.

• A30, from 8pm July 8 to 6am July 9, slight delays (under 10 minutes): A30 eastbound, Two Bridges - lane closure for electrical works.

• A38, from 9pm July 9 to 6am July 10, slight delays (under 10 minutes): A38 Landrake, traffic lights for installation of new average speed cameras.

• A38, from 8pm July 10 to 4am July 11, slight delays (under 10 minutes): A38 eastbound, Island Shop to Lower Clicker - lane closure for barrier/fence safety repairs.

• 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 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.

• A30, from 8pm July 16 to 6am July 19, slight delays (under 10 minutes): A30 westbound, Bolventor to Temple - lane closure for carriageway resurfacing works.

• 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.

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