The Nationals Steph Cooke on Thursday announced the Coalition government would spend $200 million flood proofing the Newell Highway between Forbes and West Wyalong.

The national highway was closed south of Forbes for six weeks during 2016 floods and calls to flood proof it have been raised at every opportunity since then.

The work "to improve flood immunity" will involve raising the existing road level at key locations, the Member for Cootamundra's press release said.

"Drainage structures are an important part of road building to ensure water can flow away from the road," Ms Cooke said.

Ms Cooke said the significant investment would ensure the major highway is kept open during wet weather and improve protection against flooding.

“Previous flood events along the route have left locals stranded and unable to get to work, schools and access basic services, so this funding will help to safeguard against this ever happening again,” Ms Cooke said.

The news is not only significant for local communities, but also for travellers and freight network users from Brisbane to Melbourne.

Forbes Mayor Phyllis Miller says the Forbes community is "brimming with excitement over the announcement".

This major arterial road sees more than 3000 vehicle movements a day, a Forbes Shire Council press release said.

It is the highway life-blood between Melbourne and Brisbane, and one of the most productive freight corridors in Australia.

"The impact of the 2016 flood is still being felt by business in both of these towns. Estimated productivity losses for the 2016 flood stand at $150 million," Council's statement said.

"This major project will improve safety for motorists as well as build resilience against future flood events and will address the need for government to spend vast amounts of money in road maintenance and flood detours.

"Over a $1million worth of repair work (was) required after the last flood."

The NSW Legislative Assembly entered caretaker mode ahead of the March 23 election on Friday. It's understood the $200 million commitment would be carried out by a reelected coalition government.

“The ambitious task ahead for the Newell Highway reflects the continued strong investment in regional infrastructure and maintenance across the next five years," Ms Cooke said.

"Freight efficiency will be improved and significant job opportunities created.

“Roads and Maritime Services will consult heavily with our key stakeholders and work with the Forbes and West Wyalong communities through the development of the project to ensure all flooding impacts are considered along this length."