Interim measure for Lake Hawthorn
28 April 2016
A low-level environmental watering of Lake Hawthorn is underway as an interim measure to help retain a refuge for thousands of waterbirds.
Up to 1 gigalitre (GL) of environmental water will be delivered through existing irrigation infrastructure over coming months.
The aquatic plants on the lakebed are an important food source for the thousands of waterbirds and shorebirds currently found at the lake.
"This watering is intended to partially fill the lake as there are few saline wetlands in the local area that can feasibly receive environmental water to provide the conditions these waterbirds need," Mallee Catchment Management Authority (CMA) Chair Sharyon Peart said.
"These birds need shallow and saline areas to wade and feed, which is different to the habitat provided by the Murray River and freshwater wetlands."
Ms Peart said there was no guarantee environmental water would be delivered to the lake in future years.
"We are in the process of working with the local community to set long-term environmental objectives that will guide the management of this site. These priorities, together with water availability, seasonal conditions and the significance of the environmental values at this site in relation to others in northern Victoria will determine if Lake Hawthorn is prioritised to receive water in the future," she said.
Environmental water being delivered to Lake Hawthorn has been provided by the Victorian Environmental Water Holder (VEWH).
The VEWH Chair, Denis Flett, said the VEWH Commission had approved the addition of Lake Hawthorn to Mallee environmental watering sites, in response to the influx of birds to the site earlier this year.
"Dry conditions and the arrival of many waterbirds to the site in January 2016 has caused Mallee CMA to reconsider management of the lake and request inclusion of Lake Hawthorn into Victoria's environmental seasonal watering plan," he said.
"The site is now providing a refuge for waterbirds and shallow watering of the lake bed in autumn will maintain suitable levels for bird habitat.
Mr Flett confirmed that strategic environmental water management meant that enough water was available to provide for all northern environmental watering priorities in 2015-16 and some carryover into 2016-17.
The delivery of water to the lake will not compete with irrigation demands as irrigation water will be delivered first, followed by environmental water.
Ms Peart noted the blue-green algae outbreak in the Murray River would be closely monitored and, if blue-green algae levels increase and pose a risk to Lake Hawthorn, the watering will cease for as long as required.
"This watering recognises the environmental value saline wetlands have in our semi-arid landscape," Ms Peart said.
Mallee Catchment Management Authority
M: 0404 088 090