[Music plays and an image appears of a split circle, and photos move through of CSIRO activities in either side of the circle, and then the circle morphs into the CSIRO logo]
[Image changes to show a black screen with white text: CSIRO acknowledges the Traditional Owners of the lands, seas and waters of Australia, specifically the Garawa, Gangalidda, Waanyi, Kukatj, Lardil, Yangkaal, Kaiadilt, Wakabunga, Nguburinji, Kalkaadoon, Mitakoodi, Mayi-Kutuna, Mayi-Thakurti, Mayi-Yapi and Mayi-Yali Peoples as Traditional Owners of the lands, seas and waters of the Southern Gulf catchments, We acknowledge their continuing connection to their culture and pay our respects to their Elders past and present]
[Images move through to show trees lining the banks of a river as the camera pans up into the sky, water running over rocks, and then an aerial view of a river running between trees, and text appears: The Southern Gulf catchments, Queensland and Northern Territory]
Narrator: CSIRO, Australia's national science agency, has assessed the risks and opportunities of developing water resources in Northern Australia's Southern Gulf catchments.
[Image changes to show the Earth and the camera zooms in on the map to the top of the border between the Northern Territory and Queensland with four catchment areas mapped out, and text appears: Southern Gulf catchment area – 108,200Km², Gulf of Carpentaria, Northern Territory, Queensland]
The Southern Gulf catchments span nearly 11 million hectares across the Northern Territory and Queensland.
[Image shows the map highlighting rivers and white dots pinpointing towns, and then varying blue colours fill each of the four catchment areas on the map, and text appears: Gununa, Karumba, Normanton, Burketown, Doomadgee, Gregory, Lawn Hill, Camooweal, Mount Isa, Cloncurry]
They include the Settlement Creek catchment, the Nicholson catchment, the Leichhardt catchment, Morning Inlet and the Wellesley Island groups.
[Image changes to show cattle staring at the camera, and text appears: Value of grazing industry - $240 million per year]
Most of the study area is used for grazing cattle.
[Image changes to show an aerial view of a mining town, and then the image changes to show another view of the mining town]
Mining takes up less than 0.05% of the area, but its annual value is more than 100 times that of grazing.
[Image changes to show an aerial view of the mining town as the camera pans towards it, and then the image changes to show an aerial view of a town as the camera pans over it]
The only large urban centre in the study area is Mount Isa, with a population of 18,000.
[Image changes to show a fishing boat sailing, and then the image changes to show an aerial view of a 4x4 towing a caravan along an outback dirt road]
Other major industries include fisheries in the Gulf of Carpentaria and tourism.
[Image changes to show an aerial view of mountainous bushland as the camera pans over it, and text appears: Indigenous Peoples make up 27% of the population]
Indigenous peoples have continuously occupied and managed the Southern Gulf catchments for tens of thousands of years.
[Image changes to show another aerial view of mountainous bushland, and text appears: 12% of the land is under Aboriginal freehold tenure as the camera pans up]
They hold significant rights and interests in land and water resources.
[Image changes to show a map with the four catchment areas, the camera pans out part of the catchment areas turn purple, and then Cambrian Limestone aquifer is mapped out in orange]
The study area contains extensive lowland alluvial clay plains as well as upland regions including the Barkly Tableland underlain by the Cambrian Limestone aquifer.
[Image changes to show an aerial view of a tree lined river]
The two largest rivers in the Southern Gulf are the Nicholson and the Leichhardt.
[Image changes to show an aerial view of two rivers lined by trees join together, and text appears: Median annual discharge into the Gulf of Carpentaria, Nicholson River – 1,873 GL, Leichhardt River – 1,211 GL]
Altogether, Southern Gulf catchments make up around 6% of the average yearly discharge into the Gulf of Carpentaria.
[Image changes to show an aerial view of a tree lined river as the camera pans along the river]
The Gregory River, a major tributary of the Nicholson, is an important perennial river in the region.
[Image changes to show a river with banks lined with trees as the camera pans along the river]
Both the Gregory and Lawn Hill Creek, a popular tourist destination, receive groundwater discharge from the Cambrian Limestone aquifer.
[Images move through to show a large dam wall, an aerial view of the dam wall as the camera pans left, and then an aerial view of a river, and text appears: Leichhardt catchment surface water entitlements – 105.7GL/year]
With five large reservoirs in its catchment serving high value industries and the city of Mount Isa, the Leichhardt is one of the more heavily regulated rivers in northern Australia.
[Image changes to show a pelican swimming, and then the image changes to show a young crocodile sunning itself on a log in the river]
Though not pristine, the Southern Gulf catchments have many unique characteristics and valuable ecological assets.
[Images move through to show waterlilies, a close view of a lily flower, an aerial view of a wide river, and then an underwater view of seagrass, and then an underwater view of a dugong swimming]
These include wetlands, creeks and rivers, mangroves, salt flats and reefs, as well as seagrass habitats for dugongs, green sea turtles and prawns.
[Images move through to show a wide view of female using a shovel, the shovel head digging into dirt and then lifting up the dirt, and then the female crouched holding the dirt in her hands]
With irrigation the Southern Gulf catchments have a climate suitable for a wide range of crops and forages.
[Image changes to show the female’s cupped hands full of dirt slowly trickling off her hands]
The opportunities and risks of developing irrigation vary between the major rivers.
[Image changes to show a map with a black border around a section of land, and then the camera zooms in on a river and white dot pinpoints a town with red highlighting sand, and text appears: Doomadgee]
Along the Nicholson River are 23,000 hectares of red, sandy and loamy soils, suitable for irrigated vegetables.
[Image changes to show an aerial view of open bushland as the camera pans over it, and then the image changes to show another aerial view of open bushland]
The sandy soils present challenges for off stream water storage, and tree crops would not be viable due to the risk of flooding.
[Image changes to show a map with black borders around the four reservoirs partially highlighted with purple and dots pinpoint towns, and text appears: Gununa, Karumba, Normanton, Burketown, Doomadgee, Gregory, Lawn Hill, Camooweal, Mount Isa, Cloncurry]
The extensive Armraynald Plain, which flanks the Gregory and Leichhardt rivers, has some of the largest expanses of grey cracking clay soils in northern Australia.
[Image changes to show an aerial view of dried grass plains, and then the image changes to show a ground view of the dry grassy plain, and text appears: Over 1 million hectares of grey-cracking clay soils]
These soils are suitable for broadacre irrigated cropping and as a location for off stream water storages.
[Image changes to show a map with a black border around a section of land on a river and a white dot pinpoints a town with green highlighting friable soil along the river, and text appears: Kajabbi]
In the Leichhardt catchment there are 100,000 hectares of friable soils suitable for irrigated horticulture.
[Images move through to show, a large gum tree on a hill with a female walking past it, dirt on a shovel and a hand holding some dirt, an aerial view of dry grass plains, and then a close view of grass]
Next to these, and up to one kilometre from the river, are heavier clay soils suitable for irrigated broadacre cropping and off stream water storage.
[Images move through to show an aerial view of a treelined river, a bird’s eye view of a tree lined river, and then a view from the water looking at a bank lined with trees, and text appears: 150GL of surface water could irrigate 12,000 ha of land]
Overall, it is physically possible to extract up to 150 gigalitres of surface water in 75% of years across the Nicholson and Leichhardt catchments.
[Image changes to show a view of the river through tree branches, and then the image changes to show a close view of water flowing over river debris]
Extracting this amount would reduce the median annual discharge from these two catchments to the Gulf of Carpentaria by 5%.
[Image changes to show an aerial view of a dirt road as the camera pans up, and then the image changes to show an aerial view of solar panels in the bush, and text appears: 30GL of groundwater could irrigate about 4,000 ha of land]
Groundwater systems across the Southern Gulf catchments have the potential to supply approximately 30 gigalitres of water per year.
[Image changes to show the solar panels beside a metal tripod in the bush]
There are currently 3.5 gigalitres of existing groundwater entitlements.
[Images move through to show an aerial view of bushland as the camera pans down, a ground view of the bush, and then a close views of crop seed heads, and text appears: Potential increase in irrigated land – 0.01% to 0.15% of study area, Potential increase in economic value – from $1m to more than $190 per year]
If developed to the upper limits of what is physically possible, the area of land under irrigation would increase from less than 0.01% to 0.15% of the study area. The total economic value of irrigated agriculture has the potential to increase from less than $1 million to over $190 million.
[Images move through to show an aerial view of an outback town beside a river, another aerial view of the town, and then a truck driving on a bridge crossing over a river lined with trees]
Studies show that additional income from mining, fishing, grazing and irrigation industries in regions such as this flows disproportionately into non-indigenous households.
[Image changes to show an aerial view of a mining town]
Concerted action by all stakeholders would be needed to deliver equitable benefits.
[Image changes to show an aerial view of a town, and then the image changes to show a reservoir with a dam wall]
The nature and scale of any water resource development depends heavily on community and government values.
[Images move through to show a bird’s eye view of the dam wall of the reservoir, a river lined with trees, and then a mountainous view of bushland, and text appears: http://csiro.au/southerngulf]
How any potential development is undertaken and managed in practice will have implications for environmental outcomes including water quality. No change in land use or water resource development is also a valid outcome. To find out more about these assessments, visit our website.
[Music plays as image changes to show a close view of long dry grass, and text appears: CSIRO is not a development proponent, This assessment aims to detail the resources of the catchment and examine how they might be used, All findings are made public to allow governments, communities and prospective developers to determine, for themselves, the best way forward based on their respective values]
[Image changes to show the CSIRO logo with text: CSIRO, Australia’s National Science Agency]
