The landslide on Kings Highway.

The landslide on Kings Highway.

The normally two-hour trip between Canberra and Batemans Bay will take motorists more than four hours because of flooding and two land slips on the most common routes between the capital and the coast.

The Kings Highway will be closed until 5pm on Thursday as part of scheduled stabilisation works, but with the closure of Nerriga Road between Braidwood and Nerriga due to flooding, the only routes available to motorists were via Moss Vale or Cooma.

This meant a trip between Batemans Bay and Canberra would take more than four hours.

The landslide on Kings Highway.

The landslide on Kings Highway.

“Northbound vehicles will need to travel via Cooma using the Hume Highway, Monaro Highway, Snowy Mountains Highway and then onto the Princes Highway,” the Live Traffic NSW website said.

“Southbound vehicles will need to travel via Wilton on the Hume Highway, Picton Road and the Princes Highway.”

Both routes are suitable for all vehicles.

A NSW Roads and Maritime Services statement warned motorists Araluen Road would also be closed to all but local traffic, with proof of address required.

A spokeswoman said local authorities were hopeful Nerriga Road would be reopened on Wednesday afternoon, but would not be suitable for heavy vehicles.

Tuesday’s landslip on the Kings Highway was the second in 24 hours, and came after torrential rain, which included more than 100 millimetres at Braidwood and over parts of the south coast over Monday and Tuesday.

The Tuesday landslide – when more than 600 tonnes of rock and debris was dislodged – occurred on an area of the road where stabilisation work was already underway, following a 1400 cubic metre landslide on the road last year.

Safety barriers, which had been installed over the past few weeks, held back much of the debris from Tuesday’s slip.

Additional safety work included removal of boulders from above the highway, and the installation of rock bolts and netting along the slope.

The highway will partially reopen at 5pm on Thursday, when one lane will be opened for travel under the guidance of traffic control, an arrangement that will likely remain in place until early next week.

But the 31-hour closure of the highway after the latest slip comes as Nerriga Road, one of the most direct alternate routes to the coast, is also closed due to flooding.

A NSW Roads and Maritime Services spokeswoman told The Canberra Times on Tuesday the authority was working with Palerang Council to find alternate routes between Canberra and the coast.

She said there had been three landslips along a 580 metre stretch of the road since the 1950s, all along Clyde Mountain. 

Meanwhile, in Canberra, the ACT government has advised residents that the Oaks Estate crossing would reopen from 4pm on Wednesday, but would then be closed between 9.30am and 3pm on Thursday to clear debris.

Motorists were advised to exercise caution on all rural roads in the territory due to the wet weather and snow, as Point Hut Crossing, Boboyan Road, parts of Mount Franklin Road, and Angle Crossing all remained closed.