Tarro Rail Bridge restrictions to be lifted 'sooner than expected'

FOUR LANES of traffic are expected to again flow over the Tarro Rail Bridge from Thursday morning after critical repairs.

Restrictions on the stretch of New England Highway have been causing traffic chaos but are expected to be lifted for the morning commute, weather permitting.

That includes opening the two outside lanes to traffic, returning the reduced speed limit to normal, and allowing restricted heavy vehicles back onto the bridge.

It comes after the first stage of "critical repairs" was carried out, after Transport for NSW prioritised getting the bridge back to normal operations as quickly and safely as possible.

The last of the essential work to get the restrictions lifted will be done tonight, as long as rain holds off.

Crews carried out urgent repairs at Tarro. Picture by Transport for NSW

The Bureau of Meteorology (BOM) has forecast a "mostly sunny" Wednesday, but rainfall could start later in the evening.

"A final inspection will occur immediately after the completion of the work before motorists and the freight sector will regain access to all four lanes of the bridge," a Transport for NSW spokesperson said.

"Further non-urgent works will be completed at a later stage."

The later works will be done during the night to minimise the effect on motorists.

Additional passenger train services between Newcastle and Maitland were scheduled to meet increased demand, and are set to continue for an extra week.

Left, The outside lanes are closed on Tarro Rail Bridge, right, banked traffic earlier this week. Pictures by Live Traffic NSW

Transport for NSW chief operating officer Roger Weeks said the lifting of restrictions would offer "welcome relief" to Hunter travellers and the freight sector.

"The lifting of restrictions on Tarro Rail Bridge have come sooner than expected," he said.

"We acknowledge the impacts these restrictions have had while Transport for NSW work crews completed these critical repairs over the past week.

"We thank the community for their patience and understanding while we have worked on the repairs to return the bridge to normal operating conditions."

The two outer lanes of the Tarro Rail Bridge, between Newcastle and Maitland, were suddenly closed earlier this month, and a 60 kilometre per hour speed limit was put in place, due to a structural issue.

Commuters have faced traffic chaos at peak hours since the snap changes.