“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.
The Katfish Reach Project is a joint partnership with the community and Government agencies to deliver the following objectives;
- Improving floodplain and wetland health
- Managing water to create a more natural cycle of flooding and drying
- Increasing native fish numbers
- Improving native fish movements and flows through the removal of barriers
- Improving the health of native plant communities
- Controlling pest animals and weeds
- Improving habitat for native animals including threatened species
- Recognising the importance of traditional Aboriginal culture and European heritage
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.
Stone Weir within the Katfish Reach site (Photo: DENR)
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.