WaterNSW has announced it will prosecute five people over alleged water theft on the Barwon-Darling.

The legal action was launched after media revelations last year.

The authority says prominent irrigator Peter Harris and his wife Jane Harris, who own a major cotton farm in the state's north-west, are accused of taking water when the flow conditions did not permit it, and breaching licence and approval conditions.

Charges have also been laid against cotton grower Anthony Barlow, Frederick and Margaret Barlow.

The Barlows are accused of pumping during an embargo and pumping while metering equipment was not working.

WaterNSW is also investigation other alleged water thefts in the Barwon-Darling and other areas, and says it will update the public on those matters soon.

Chief of the National Irrigators Council Steve Whan said the allegations should not reflect negatively on the entire industry.

“They're obviously two irrigation families out of what the ABS says is 9,500 irrigation businesses on the Murray Darling Basin,” Mr Whan said.

“One of the things that the rest of the irrigators around Australia would want to say is don't judge them all on the basis of accusations against a couple.

“And remember those accusations still need to be proven.”

The Menindee Community Water Consultative Group says the maximum penalty of about $247,500 should be higher.

“Not just a slap on the wrist and told you can't do it anymore,” the group’s chair Karen Page said.

“I say pay big time, have their water entitlements taken off them.”