Annual environmental water priorities in the Macquarie catchment

The resilience of wetland plants and recovery of native fish populations will be the focus of managed watering events targeting the Macquarie Marshes and mid-Macquarie River this year.

Priorities for 2018–19

In 2018-19, the management of water for the environment will focus on enhancing the resilience of wetland vegetation in the Macquarie Marshes and supporting the recovery of native fish populations in the mid-Macquarie River.

Since December 2016, rainfall in the catchment and lower floodplain has remained well below average. In the year ahead, the Bureau of Meteorology forecasts drier than average conditions across the region.

Water managers will target a 20,000-hectare area of the Marshes to improve habitat health, provide feeding opportunities for waterbirds, support the recovery of native fish and the wetland food web, and replenish groundwater systems.

If drought conditions persist, the aim will be to avoid critical losses and maintain refuge sites.The approach is part of a three-year strategy, developed in consultation with the Environmental Water Advisory Group. It will allow water managers to carry over water for use in future years should dry conditions continue.

The amount of water available is unlikely to increase, so carryover will be used to meet the needs of the Macquarie system. However, the management of water for the environment provides flexibility to respond to natural events that may occur during the year.

Further details on watering priorities for 2018–19 can be found in the Annual Environmental Watering Priorities 2018–19 (PDF 3.6MB).

Highlights from 2017–18

Natural floods in spring of 2016 provided a strong foundation for water managers to build on in 2017–18.

 In April-May 2017, 26.6 gigalitres of water was delivered into the Macquarie Marshes to further enhance soil moisture. Larger reed beds and lagoons retained standing water over the winter period.

More than 100 gigalitres was used to inundate core semi-permanent areas, including reedbeds, water couch, mixed marsh and river red gum forests. Between July and December 2017, two flows totalling approximately 135 gigalitres of environmental water were delivered to the Macquarie Marshes.

Water manager Paul Keyte said some of the significant ecological outcomes included an initial ’pre wet‘ flow delivered between July and August 2017. This flow successfully primed the system, improving water efficiency and boosting standing water in the channels and shallow groundwater systems, resulting in a larger than expected area being inundated. Sinclair’s and Louden’s lagoons were fully replenished.

‘A main flow to the Marshes between August and November 2017, inundated semi-permanent wetland vegetation communities including reedbeds, water couch and mixed marsh and river red gum forest’, Mr Keyte said

‘Less than 70 pairs of white Ibis, were observed breeding in one colony. Waterfowl, including swans, darters, pied and little black cormorants, also bred as expected, in low numbers.

‘The flow also supported conditioning, breeding and dispersal of native fish, including Murray cod and golden perch in the mid-Macquarie River and lower Macquarie River channels.

‘The lower Macquarie River received approximately 22 gigalitres of outflow below the Marshes and it is estimated about 5 gigalitres entered the Barwon River’, he said.