Member for Cootamundra Steph Cooke said the announcement means the Wyangala Dam wall-raising will be fast tracked, guaranteeing water security for communities across the Lachlan Valley.

The project will increase the size of the current dam by more than 50 per cent - or 650 gigalitres.

"The Wyangala Dam expansion is vital for ensuring water security and flood mitigation for the towns and villages, industry, agriculture and horticulture across the region," she said.

"The NSW Nationals have fought tooth and nail to fast track these dam projects which will be a legacy to the people of NSW.

"We will have shovels in the ground by October for this historic project. Our communities have done it tough with the drought and COVID-19, but we are resilient and will look back knowing that we have been responsible for the recovery of our state's economy.

"Thanks to the improved water security for our prime agricultural regions, farmers will be able to produce food and vital exports that will play a crucial role in our nation's future."

Deputy Premier and Leader of the NSW Nationals John Barilaro said this is a game changer for the entire state, with water security the most important and vital resource for the people of NSW.

"Today's announcement means the Wyangala Dam wall-raising can be fast-tracked, improving long term water security sooner while creating immediate employment and economic benefit at a crucial time for regional NSW," he said.

"We have not seen this kind of water infrastructure build since the 1980's and not only are we creating local jobs but we are increasing vital water security across this state, and for me there's nothing more important than that."

At a funding announcement earlier in the year, Mr Barilaro said future generations would be disadvantaged if the project didn't go ahead.

"The time is now to build dams in NSW, to be bold in our vision for regional communities and take control of our future," he said.

"We are disadvantaging future generations if we don't learn our lesson in this drought and build more dams now."

Ms Cooke has also welcomed the news that local businesses can register their interest to work with WaterNSW on the Wyangala Dam project.

Minister for Water, Property and Housing Melinda Pavey announced earlier in the month that an online business portal for local businesses who were keen to be part of the $650 million damn wall raising project had been launched.

Ms Cooke said she encouraged local businesses to register.

"This is a fantastic economic opportunity for our communities, particularly at a time when other work might be slowing down," she said.

"This is an opportunity for businesses of all sizes, so I urge anyone who wants to be part of this project to register their interest. Be part of improving water security in the Lachlan Valley, and be part of this incredible infrastructure project."

Mayor of Cowra, Councilor Bill West, said raising the project was a unique opportunity for businesses.

"Wyangala Dam is an infrastructure asset with many elements soon to be established to increase the wall height," he said.

"These components will positively lend themselves to our local businesses being actively involved.

"There will be many projects available for local businesses to be considered for.

"One that I can think of immediately is the proposed relocation of Reflections Holiday Park.

"This is a unique opportunity for Cowra shire businesses to register their interest with Water NSW and be actively involved in what will be a significant project for the shire and wider community," he said.

Local business owners can register their interest online at www.waternsw.com.au/wyangalabusiness