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About
the project
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The vision for the Katfish Reach Project is "A healthier and more productive aquatic and floodplain ecosystem that everyone can enjoy."
The Katfish Reach Project is hoping to provide the community with a visible demonstration that the health of the river and its floodplain, and the plants and animals (notably native fish) that depend upon these habitats, can be restored to better condition through coordinated actions that address the major threats. |
Key objectives
Achievements
Proposed actions
Project reports
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The key objective for Katfish Reach is to create an adaptive hydrological system to enhance native fish and improve floodplain health.
The following on-ground actions are proposed:
• Construct environmental regulators to enable flooding of the floodplain at low river flows;
• Increase in-stream flow and facilitate fish passage by modifying or replacing existing structures;
• Temporarily dry The Splash and Eckert Creek north and south arms while maintaining flow through Eckert and Sawmill Creeks; |
Stone Weir within the Katfish Reach site (Photo: Bill Doyle).
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• Improve wetland management of Ngak Indau, Katarapko Island, Horsehoe lagoons and Gerard Wetlands;
• Secure the nationally threatened Murray hardyhead fish population at the Berri Evaporation Basin by managing drainage water.
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| Achievements |
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Floodplain watering... since 2004 various wetlands and floodplains within the Katfish Reach site have received water to promote environmental flow for ecological benefits. Below is a list of wetlands and floodplains to receive water for environmental flow:
| Wetland / floodplain |
Years when environmental water received |
| Ngak Indau |
2004, 2005, 2006 & 2009 |
| Piggy Creek |
2005 & 2006 |
| Katarpko Creek Wetland |
2005, 2006 & 2010 |
| Carpark Lagoons |
2005, 2006 & 2009 |
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Vegetation
within Carpark Lagoons prior to environmental watering, 2009 (Photo: DENR)
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Vegetation
within Carpark Lagoons after environmental watering, 2020 (Photo: DENR) |
Wetland monitoring... to determine management options and assess the outcomes of environmental watering, monitoring programs have been established at the wetlands, including Ngak Indau, Piggy Creek, Katarapko Creek Wetland and Carpark Lagoons. The monitoring program records data for fish & tadpoles, water quality and groundwater, water birds, frogs, trees and vegetation.
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New inlet and outlet structure for the Ngak Indau wetland... during the 2009 filling of the Ngak Indau wetland the existing outlet structure was undermined thus destroying its ability to hold water within the wetland. A new outlet structure was required to enable the floodplain vegetation surrounding the wetland to be flooded at pool level.
The new outlet structure was completed in June 2010 due to funding received from the South Australian Murray-Darling Basin Natural Resources Management Board, and has increased the area of inundation from 10Ha to 21.4Ha when environmental water becomes available. The long term benefits of the new outlet structure for the wetland includes:
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Construction on the new outlet structure for Ngak Indau wetland (Photo: DENR) |
• Improve the health of existing riparian and aquatic vegetation;
• Provide conditions favourable for regeneration;
• Improve the quality of the surface water when inundated;
• Provide conditions favourable for waterbirds, native fish and amphibians. |
Gerard (Indigenous) trainee 1 year baseline monitoring program... through the Aboriginal Lands Trust, The Murray-Darling Basin NRM Board and DENR, an opportunity arose where six Gerard trainees were taught river and wetland ecological monitoring techniques. Commencing September 2009 DENR Wetland Ecologist worked with the Gerard trainees on a monthly basis undertaking a baseline survey at five sites selected along The Splash which occurs on both National Park and Aboriginal Land Council land.
The trainees were taught monitoring techniques for water quality, small and large bodied fish identification, River Red Gum and Black Box tree condition monitoring, vegetation monitoring, and groundwater monitoring techniques.
A new inlet
structure was also installed by SA Water through a Living Murray grant
to increase water flow and improve fish passage.
A copy of the report can be viewed in project reports.
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| To create an adaptive hydrological system to enhance native fish and improve floodplain health, the following four on-ground actions are proposed: |
1. Remove barriers to fish movement and increase waterway spring flows.
The removal or modification of six in-stream fish and flow barriers throughout Katfish Reach will increase in-stream flow and facilitate fish passage (see map).
A concrete vertical slot fish-way will be placed on the new overshot regulator at the inlet of Eckert Creek. The Katarapko Stone Weir will be lowered by 340mm to allow river flows greater than 5,000 megalitres per day to overtop the Weir. The Weir will also be fitted with a rock fish ramp. |
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The present barriers significantly restrict flow down both the Eckert Creek System and Katarapko Creek. A number of these barriers also stop fish movement at low flows. The new and modified structures will improve the ability to stimulate conditions suitable for breeding of large bodied fish such as Murray Cod and Callop. |
2. Promote environmental flows to improve floodplain health.
An environmental regulator will be constructed at the mouth of The
Splash in conjunction with smaller regulators at the mouth of Piggy and
Sawmill Creeks. The environmental regulators will enable 1,000 hectares
of Eckert Creek floodplain to be flooded at low river flows by
diverting water from upper Lock 4 pool level.
River regulation and drought have
significantly reduced the numbers and height of flood events, impacting
on the health of waterways, wetlands and the floodplain. Vegetation,
fish, waterbirds and frogs have all been affected by the reduced
floodplain flooding.
3. Vary water levels to improve wetland health.
To improve wetland health, the following management options are proposed:
• Restore the Katarapko Island Saline Water Disposal Basin by replacing or modifying the existing hydrological structures to improve inundation duration and frequency during a natural flood event;
• Relocate the Eckert Creek Widewater irrigation and domestic water supply pumps to enable the lowering and raising of the wetland's pool level;
• By utilising the proposed Eckert Creek system in-stream structures, The Splash and Eckert Creek Northern and Southern Arms can be temporarily dried while maintaining flow through Eckert and Sawmill Creeks;
• Reinstating a hydrological regime that is similar to the natural water variation will benefit plants, fish, frogs and waterbirds creating a healthier aquatic ecosystem. |
4. Secure the nationally threatened Murray hardyhead fish population.
A small population of this nationally threatened fish species is
located in the Berri Saline Water Disposal Basin. Through the
management of limited irrigation drainage water volumes, the present
habitat site (1.9ha) will be secured and an additional habitat site
(14ha) created within the salinity range to favour the species.
Reduced irrigation drainage water inflow into the Berri Saline Water
Disposal Basin has resulted in the majority of the Basin drying out
during the summer months.
The Berri Murray hardyhead are one he last remaining populations of
this salt tolerant native fish within the Murray Darling Basin. |
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