Twenty gauges will be installed to better monitor water flows in response to flooding at Menindee, according to the New South Wales government.
Several homes were inundated and dozens remained at risk after authorities failed to predict the large flows that spilled into Menindee Lakes from December into January.
According to authorities, this was at least partly due to unmeasured water from Taylawalka Creek re-entering the system.
NSW Water Minister Kevin Anderson confirmed the installation of the first five Commonwealth-funded hydrometric stations was underway at Wilcannia, Bourke, Walgett, Quambone and Brewarrina.
"These gauges provide live information on flows coming down rivers," he said.
"This information is shared with other agencies, including the State Emergency Service and Bureau of Meteorology."
The Taylawalka is a floodplain near Wilcannia, which runs adjacent to the Darling River.
It flows roughly once a decade following heavy rainfall in the catchment area further north.
According to a Water NSW spokesperson, there are several types of gauges.
"The basic stream gauge is a staff gauge post [pictured above] or series of them up the river bank, used to read the water level in a repeatable way," he said.
"To get more timely information, more sophisticated instruments are installed into a shelter at the top of the bank, ideally above flood levels, and sensors to read water level or water quality are plumbed down the bank to sit in the water when the stream is flowing.
"These automated measurements are then sent by telemetry to a central database where they are captured and made available for use."
The Water NSW spokesperson said a well maintained stream gauge can last "a very long time" and there were sites along the Darling that had been in operation for more than 100 years.
"These locations are most valuable because it allows historical comparisons," he said.
Price of installation
The spokesperson said the cost for both installation and maintenance varied between units, due to their requirements and location.
"A typical gauge might cost in the vicinity of $40,000 to $60,000 to install," he said.
"The operation of them also depends on the complexity of the site, including what data is collected, how often it needs servicing, the labour cost, and the cost of replacement parts.
"For a river flow site, it will on average cost around $15,000 a year to operate.
"Some sites cost less and others can cost far more due to factors like the number of times it needs to be visited, and how remote it is."
Locations limited
Water NSW said there were 12 sites in the Darling system south of Bourke, prior to the Darling River, that reached the Menindee Lakes network.
This included gauges at Wilcannia and on the Talyawalka.
"[They are] at the same point to calculate the total flow of the Darling River system at that point," the spokesperson said.
"Locations for the effective measuring of flows between Menindee and Wilcannia will be limited due to the landscape of the river in this area."
NSW Water Minister Kevin Anderson said the Department of Planning and Environment was considering feedback on the location for the remaining 15 gauges.
