Cornwall's motorists will have 18 road closures to avoid nearby on the National Highways network this week.

And one of them is expected to cause moderate delays – with drivers facing a wait of between 10 and 30 minutes.

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

• A30, from 8.30pm April 15 to 6am April 24, slight delays (under 10 minutes): A30 eastbound, Longrock Bypass carriageway closure for resurfacing, diversion via minor road through Longrock.

• A30, from 8.30pm April 15 to 6am April 24, slight delays (under 10 minutes): A30 westbound, Longrock Bypass carriageway closure for resurfacing, diversion via minor road through Longrock.

• A30, from 11am February 12 to 6am April 27, slight delays (under 10 minutes): A30 eastbound, Longrock Bypass lane closure for resurfacing.

• A30, from 7.30pm February 12 to 6am April 27, slight delays (under 10 minutes): A30 westbound, Longrock Bypass lane closure for resurfacing.

• A30, from 7pm January 21 to 6am May 3, slight delays (under 10 minutes): A30 westbound, Two Bridges exit and entry slip road closures for South West Water works. Picnic site and toilets will be closed, exit slip diversion via A30 westbound to Plusha, B3257 and minor road to Lewannick, entry slip diversion via minor roads to Plusha. Traffic wanting to travel eastbound, on the A30 will be diverted via Fivelanes.

• A30, from 7pm March 10 to 6am May 3, slight delays (under 10 minutes): A30 westbound, Lewannick exit slip road closure for South West Water works, diversion via A30 westbound to Plusha, B3257 and minor road to Lewannick.

• A30, from 4am September 23 2023 to 6am June 9 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 June 9 2024, slight delays (under 10 minutes): A30 Carland Cross to Chiverton Cross improvement scheme.

And a further 10 closures will begin over the next two weeks:

• A38, from 7pm April 22 to 6am June 1, 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 7pm April 22 to 6am April 26, slight delays (under 10 minutes): A30 eastbound, Scorrier to Boxheater (B3285) and westbound, Boxheater to Chiverton Cross carriageway closures for improvement scheme, eastbound, diversion via Blackwater, B3277, A3075 and B3285, westbound, diversion via B3285 and A3075.

• A30, from 7pm April 24 to 6am April 27, slight delays (under 10 minutes): A30 westbound, Liftondown to Launceston lane closure for horticulture.

• A38, from 8pm April 25 to 6am April 26, slight delays (under 10 minutes): A38 Tideford traffic signals for National Grid works.

• A30, from 7pm April 26 to 6am April 29, slight delays (under 10 minutes): A30 eastbound, Scorrier to Boxheater (B3285) and westbound, Boxheater to Chiverton Cross weekend carriageway closures for improvement scheme, eastbound, diversion via Blackwater, B3277, A3075 and B3285, westbound, diversion via B3285 and A3075.

• A30, from 8pm April 29 to 6am April 30, 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 9am to 4pm on May 1, slight delays (under 10 minutes): A30 both directions Longrock Bypass - lane closure for survey works.

• A30, from 7pm May 1 to 6am May 4, slight delays (under 10 minutes): A30 both directions Loggans Moor to Treswithian closed for general maintenance works. Diversion via minor road through Roseworthy and Connor Downs.

• A30, from 7pm May 6 to 6am May 10, slight delays (under 10 minutes): A30 both directions Scorrier to Boxheater (B3285) carriageway closures for improvement scheme, eastbound, diversion via Blackwater, B3277, A3075 and B3285, westbound, diversion via B3285, A3075, Blackwater and A3047 to Avers junction.

• A30, from 8pm May 6 to 6am May 9, slight delays (under 10 minutes): A30 both directions St Erth Roundabout to Loggans Moor Roundabout closed for general maintenance works. Diversion via B3301 through Hayle.

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