Drivers in and around Cornwall will have 25 National Highways road closures to watch out for this week.

And three of them are expected to cause moderate delays – with motorists facing waits 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 April 22 to 6am May 12, moderate delays (10-30 minutes): A30 eastbound, Chiverton exit slip road closed for Chiverton to Carland improvement scheme, diversion via A30 eastbound, exit at Chybucca, B3284, A3075.

• A30, from 8pm April 22 to 6am May 12, moderate delays (10-30 minutes): A30 westbound, Chiverton exit slip road closed for Chiverton to Carland improvement scheme, diversion via A30 westbound, exit at Scorrier, A3047, Wheat Busy loop, B3277.

• A38, from 7pm January 13 to 6am June 4, slight delays (under 10 minutes): A38 eastbound, Carkeel roundabout to Saltash Tunnel carriageway closed for sign erection works. Diversion via the B3271.

• 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 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 20 closures will begin over the next two weeks:

• A30, from 7pm May 5 to 6am May 8, slight delays (under 10 minutes): A30 both directions Loggans Moor to Treswithian carriageway closed for resurfacing. Diversion via Connor Downs.

• A30, from 9am to 3pm on May 6, slight delays (under 10 minutes): A30, both direction,s Longrock, lane closure for barrier/fence safety repairs.

• A38, from 7pm May 6 to 6am May 7, slight delays (under 10 minutes): A38 westbound, Trerulefoot to Lower Clicker convoy working for carriageway patching works.

• A38, from 8pm May 6 to 6am May 16, slight delays (under 10 minutes): A38 both directions Twelvewoods Roundabout to Turfdown Roundabout carriageway closed for resurfacing, diversion via A390, B3269, B3268 and Turfdown Road. HGV diversion via A30 and A388.

• A38, from 8pm May 7 to 6am May 8, slight delays (under 10 minutes): A38 both directions Carkeel roundabout to Liskeard Road two-way signals for sign erection works.

• A30, from 9pm May 7 to 6am May 8, slight delays (under 10 minutes): A30 both directions Newtown Roundabout to Chy-An-Mor roundabout, carriageway closed for National Grid works. Diversion via Longrock local roads.

• A30, from 7pm May 8 to 6am May 10, slight delays (under 10 minutes): A30 both directions Treswithian to Tolvaddon carriageway closures for maintenance works, diversion via A3047.

• A38, from 8pm May 8 to 4am May 9, slight delays (under 10 minutes): A38 westbound, Moorswater entry slip road closure for barrier/fence repair works, diversion via B3254, A390 to Island Shop.

• A30, from 9pm May 8 to 6am May 10, slight delays (under 10 minutes): A30, both directions, Temple to Four Winds - lane closures for safety barrier repair.

• A38, from 6.30pm May 10 to 8am May 11, slight delays (under 10 minutes): A38 eastbound, Carkeel roundabout to Saltash Tunnel carriageway closed for sign erection works, diversion via the B3271.

• A38, from 7pm May 10 to 8am May 11, slight delays (under 10 minutes): A38 westbound, Saltash Tunnel to Carkeel Roundabout -carriageway closed for sign erection works, diversion via B3271.

• A38, from 8pm May 11 to 5am May 12, slight delays (under 10 minutes): A38 eastbound, on approach to Tamar Bridge - lane closures for toll sign changes.

• A30, from 8pm May 12 to 6am May 14, slight delays (under 10 minutes): A30 both directions Highgate Hill exit slip roads, lane closure for structure inspections.

• A30, from 8pm May 12 to 6am July 5, moderate delays (10-30 minutes): A30 both directions Chiverton to Carland - carriageway closure for Chiverton to Carland improvement scheme, diversion eastbound, via A3075, B3285, B3288, re-join A30, diversion westbound, via B3288, B3285, A3075, re-join A30.

• A30, from 8pm May 12 to 6am May 15, slight delays (under 10 minutes): A30 both directions Loggans Moor to St Erth carriageway closed for drainage works. Diversion via B3301 through Hayle.

• A38, from 8pm May 13 to 6am May 14, slight delays (under 10 minutes): A38 eastbound, Moorswater exit slip closed for electrical works, diversion via A38, A390 and B3254.

• A38, from 8pm May 13 to 4am May 14, slight delays (under 10 minutes): A38, both directions, Carminnow to Turfdown - 2-way signals for electrical works.

• A30, from 7pm May 15 to 6am May 17, slight delays (under 10 minutes): A30 both directions Liftondown to Pennygillam - lane closure for horticultural works.

• A30, from 7pm May 19 to 6am May 22, slight delays (under 10 minutes): A30 both directions Tolvaddon to Avers, junction carriageway closed for maintenance works, diversion via B3047.

• A30, from 8pm May 19 to 6am May 21, slight delays (under 10 minutes): A30 both directions Innis Down - lane closure for Bypass Construction Scheme.

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