The water supply in Broken Hill, New South Wales has been secured via a 270-kilometre pipeline from the Murray River at Wentworth, but surrounding towns will not benefit from the project.

Key points: The $500-million pipeline was announced in 2016 when Broken Hill was months away from running out of drinking water

The $500-million pipeline was announced in 2016 when Broken Hill was months away from running out of drinking water Groups are criticising the pipeline, saying Government should have focused on improving management of the Murray-Darling Basin

Groups are criticising the pipeline, saying Government should have focused on improving management of the Murray-Darling Basin WaterNSW says the town will be supplied entirely by water from the Murray River by April

Properties along the Darling River and the town of Pooncarie will not be connected to the pipeline, and will have to rely on a dwindling supply of water held in four temporary block banks.

The $500-million project was announced in 2016 after Broken Hill came within months of running out of drinking water, and will be commissioned today by the Deputy Premier John Barilaro and Member for Barwon Kevin Humphries.

"We've been able to finance and construct the largest piece of water infrastructure in rural NSW since the Snowy Hydro," Mr Humphries said.

Despite the improvement to Broken Hill's water security, many in the region argue the Government should have instead improved the management of the Darling River and Menindee Lakes.

"We've always had a secure water supply from the Darling," Broken Hill Mayor Darriea Turley said.

"We struggle when there's a drought but certainly that is the issue and the Government should have addressed these issues."

Tom Kennedy from the Darling River Action Group said taking Broken Hill off the Darling River would leave the Lower Darling River vulnerable.

"The Darling River won't need as much water coming down to have a guarantee of water for Broken Hill," Mr Kennedy said.

"So in essence there'll be less water coming down the Darling River and the Menindee Lakes will be drained a lot quicker."

'Government don't care about the lower Darling'

The Menindee Lakes, which have recently become known as the scene of mass fish kills over summer, have supplied Broken Hill with drinking water for decades.

Menindee and Wilcannia will remain reliant on the Darling River, which lead residents to believe the Government has given up on their stretch of the river.

"The Government don't care about the lower Darling — not one little bit," Menindee resident Karen Page said.

"They've sacrificed the health and wellbeing of the small towns for the Broken Hill pipeline," she said.

Like many Menindee residents who rely on the Darling River for household use, Karen Page has become dependent on carted water and water donations from kindly strangers.

Ms Turley said concerns have been validated by several scientific reports into the recent fish kills in Menindee.

"We are in drought now, but before that we had a water crisis in the Darling and we believed that was because there was over-extraction, which has now been proven," she said.

Full switch-on to take weeks

Water from the Murray River will slowly make its way into the Broken Hill water system from a storage tank at the local treatment plant.

"I expect over the next month or two there'll be a transition for domestic, commercial and industrial use," Mr Humphries said.

"That water will be coming from the new bulk water delivery system from the Murray."

WaterNSW spokeswoman Kate Thomson said in a statement the city would be entirely supplied with Murray water by April.

"Over several weeks residents will see an increase in the proportion of River Murray water flowing through their taps," she said.