Map of the Intersecting Streams catchment showing waterways, wetlands and locations of water for the environment deliveries made in 2019–20.

The watering aims identified in the Intersecting Streams Annual Environmental Watering Priorities for the 2019–20 water year under dry to very dry conditions were assisted by wetter conditions in early 2020 that resulted in natural flows.

Unlike regulated catchments, the management of water for the environment in the Intersecting Streams catchment is largely reliant on improving outcomes from unregulated or natural flows in the rivers. The aim is to balance flows in the rivers to meet the needs of instream ecosystems and support floodplains and wetlands.

In 2019–20 the Commonwealth Environmental Water Holder identified priority actions to guide the management of their portfolio of water licenses for this system, subject to river flows.

In the Narran system licensed water entitlements aimed to:

  • support replenishment flows to maintain habitat at Narran Lakes
  • support flows to maintain and, where possible, improve habitat and support naturally triggered waterbird breeding
  • support flows that replenish refuge waterholes for native fish in the Narran system.

In the Warrego system licensed water entitlements aimed to: 

  • supplement natural flows that provide connectivity between the Warrego and Barwon–Darling rivers
  • balance water needs between the Warrego River floodplain and Darling River, facilitated by the operation of water management structures on Toorale National Park and State Conservation Area.

Due to extended dry conditions in the Intersecting Streams catchment, the Intersecting Streams Annual Environmental Watering Priorities 2019–20 (AEWP) did not expect connectivity to occur to the Darling River. If rainfall occurred and licenses were activated, the priorities of the AEWP were to:

  • replenish waterholes for native fish habitat
  • direct water to Narran Lake
  • maintain extent, improve condition, and promote recruitment of vegetation in the catchment.

These priorities included all rivers within the Intersecting Streams catchment.

Between February and April 2020, a total of 1442 gigalitres flowed past St George in Queensland and into the Culgoa, Birrie, Bokhara and Narran rivers. This large inflow from the Balonne increased resilience and replenished habitat throughout the river systems. Traditional Owners who were monitoring the Narran Lakes suggested it was primed for a bird breeding event.

Rainfall in March 2020 activated the Commonwealth’s licenses for Toorale National Park and State Conservation Area (Toorale). The Commonwealth Environmental Water Holder contributed 16.2 gigalitres of the 45-gigalitre-flow that reached the Darling River from the Warrego.

More than 11,000 hectares of floodplain at and around Toorale was inundated. The flows connected the Darling River with the floodplain via the Talowla channel for the first time since 2010. NSW National Parks and Wildlife Service (NPWS) observed brolga chicks in the national park.

Unregulated Commonwealth entitlements in the Moonie River were activated in early 2020, contributing about 4.5 gigalitres of water for the environment.

Monitoring by the Murray–Darling Basin Authority, Commonwealth Environmental Water Office, and NPWS found that some AEWP outcomes were met in early 2020, including:

  • replenishment of waterholes and refuges throughout the Intersecting Streams and the Barwon–Darling catchments
  • significant inflows to Narran Lakes
  • recovery of some riparian and wetland vegetation.

Boera Dam at Toorale.

Work on the Water Infrastructure Project at Toorale National Park and State Conservation Area (Toorale) has been ongoing throughout 2019–20, led by the Department of Planning, Industry and Environment.

The project involves removing, modifying or decommissioning existing water infrastructure on Toorale to support environmental outcomes.

The largest instream barrier on Toorale, Peebles Dam, was removed in October 2019. Floods down the Warrego River since then have flowed unimpeded through this reach to the Darling River.

The next stage of the project will involve modifications to infrastructure at Boera, Homestead and Booka dams.

Designs for Boera and Homestead dam works have been finalised and a comprehensive environmental assessment completed and approved.

The project involves modifications to 4 dams that were constructed across the Warrego River to support agricultural practices associated with the former Toorale Station. These dams were initially installed as part of property improvements during the late 19th century, primarily to increase floodplain watering and grazing capacity, and in later years store water for irrigation. Historic management of the flows on Toorale using the existing infrastructure has created high conservation value aquatic and wetland habitats. However, it has also reduced instream connectivity and created barriers to fish movement within this reach of the river. The aim of the project is to:

  • increase water flow capacity through the lower reaches of the Warrego River and into the Darling River for downstream environmental benefits
  • improve fish passage
  • protect and maintain environmental, cultural and historic values.

For more information, visit the Toorale Water Infrastructure Project webpage.