Drought experiment: environmental flows resurrect irrigation country by Alex Nicol
GroundCover™ Issue: 45
IT PROVED to be an eye-opening experiment. When in irrigation season 2001- 02 the Murray Wetlands Working Group offered environmental flows to landholders, it got 10 takers. There was something like 250 ha of country involved and 600 ML of water. This year the group already has applications for water from 50 landholders and in the words of the chairman, Howard Jones, "we've got to be careful that we don't outgrow our resources" .
The country revived by those environmental flows is lignum swamp, flood runners and black box swamps that might not have seen water for 20 out of 30 years. The results have been astounding.
Coordinator Trish Alexander says in that first year the seemingly dead black box flowered, river red gums germinated and a whole variety of wetland plant life came back. "We got ribbon weed, spike rushes, lilies, the lignum flowered and all this has set seed," she said. "Then we got the animal life - birds, including some rare migratory birds, frogs breeding and in some places we've got the Southern Bell Frog back."
None of this comes as a surprise to Howard Jones. He's had the experience of seeing the Moira Lake in the Barmah Forest dried out three times in the last eight years with amazing results.
"You would have thought that all of the vegetation would have been killed off, but the draining and the periodic flooding have brought a whole range of life back to the country.
"Egrets, for example, have quite a short life span and there were occasions when they weren' t being given a chance to nest at all. Now, you can look across the country, particularly up around the Wakool wetlands, and see dots of country coming back. We're even starting to see brolgas poke their heads up, not many, but some. There's tremendous potential."
From a purely practical point of view, the return of birdlife promises more natural insect control while the wetlands provide an environmental filtering system.
The environmental flows are delivered to the properties through Murray Irrigation Ltd's infrastructure. That organisation has driven the project with an aggressive advertising scheme and, in Mr Jones's words, "has come in for criticism from some who don't want to see change, but they've worn that". Once on the property it's the farmer's responsibility to get the water to the wetlands.
Ms Alexander says that can mean digging small channels or otherwise channelling water. Irrigation season 2002-03 saw 3,600 ML diverted to environmental use across 572 ha. In the worst irrigation season in memory, just how did those irrigators feel about sending that precious water down the channel?
"I think the tough season helped," says Ms Alexander. "They couldn't use the water for their crops anyway, but all of the growers involved were excited about the results on their place. It wasn't just a clump of dead and dying trees down the back.
Region North, South, West