Flows highlight efficient water management
The 2018 watering of the internationally significant Gunbower Forest has highlighted the importance of efficient and effective water use.
Only 48 of the allocated 82 gigalitres was used to irrigate the forest, and most of it was water that had already been used to meet environmental needs in the Campaspe and Goulburn rivers upstream.
Also, about 40 per cent of the water delivered to the forest flowed back into the Murray River, to be used again downstream.
“That is efficient use of water in anyone’s language,” North Central Catchment Management Authority (CMA) Program Delivery Executive Manager Tim Shanahan said.
“The decisions around water use in the forest were based on local conditions, local community feedback and results of monitoring the forest’s response to the water.
“But it wasn’t only the forest that benefited. Our important native fish populations were given a boost too, with vital food and nutrients coming off the floodplain and back into our creeks and rivers in spring when they needed it most.”
Mr Shanahan said managing the allocated Gunbower flows meant managing within a system that puts people first.
“When it came to the water delivery, farmers received water down the Gunbower Creek before the environment” he said.
“During irrigation season in our catchment, the forest accessed water only after irrigators did.
“That is why we started the watering in winter. Once the irrigation season arrived, inflows dropped dramatically from 700 megalitres to an average of 200 megalitres a day into the forest.
“Like farmers, we know it’s important to use water when it’s available, and state and federal authorities had the water available.
“We then adapted the flows in response to a dry spring and high irrigation demand. Interestingly, modelling showed that despite the dry period, without regulation the forest would still have received water in spring.
Efficient water usage and good management is only part of the Gunbower story. Getting bang for the buck is also important.
“The understorey vegetation in the red gum forests and box woodlands is in the healthiest condition it has been since we began monitoring it in 2005, though it still has some way to go towards making a full recovery,” Mr Shanahan said.
“Those trees provide shelter, feeding and nesting habitat for animals, and the forest is also home to more than 50 rare and threatened plants and animal species.
“Thousands of waterbirds are now foraging and roosting, and we have also discovered colonies of waterbirds nesting in new areas.
“That’s important for the local economy as well as the forest, bringing tourism and recreation opportunities as well as providing important places for cultural connection to the country.
“The overall health of the forest is slowly improving. Restoring the forest from more than a century of changed flooding patterns is going to take time.
“Water for the environment is the life support of Gunbower Forest. It is providing Mother Nature with a much-needed helping hand and helping build resilience if dry conditions continue.”
The Gunbower Forest Flooding for Life project is delivered by the North Central CMA in partnership with Goulburn-Murray Water, Murray-Darling Basin Authority, the Commonwealth Environmental Water Office, the Victorian Environmental Water Holder, DELWP and Parks Victoria. It is part of The Living Murray program, a joint initiative of the New South Wales, Victorian, South Australian, Australian Capital Territory and the Commonwealth governments, coordinated by the MDBA.