Naracoorte Creek, northeast from Naracoorte
2009 Aquatic Ecosystem Condition Report
- Dry in autumn and spring 2009.
- Likely to be at least moderately enriched with nutrients when wet due to the surrounding land uses.
- Riparian vegetation limited and consisting of a few gums over introduced grasses.
- Moderately eroded banks with some silt deposits in the channel.
About the location
Naracoorte Creek is a large stream in the lower South East that has a catchment area over 750 km2. The creek rises as two branches in western Victoria to the south of Bringalbert that eventually join together to form the one channel about two kilometres west of Kybybolite in South Australia. The creek then flows in a westerly direction through Naracoorte and a series of ephemeral lakes, including Lake Ormerod, before discharging into the upper part of Drain E. The major land uses are grazing and cropping.
The monitoring site was located in the mid to lower reaches on Cadgee Road, about six kilometres north-east of Naracoorte.
The creek was given a Fair rating because the site sampled showed moderate changes in ecosystem structure and some changes to the way the ecosystem functions. There was evidence of human disturbance, including poor riparian habitat, bank erosion and fine sediment deposition.
The creek was dry in autumn and spring 2009, so macroinvertebrate and water quality data were not available for the site inspected.
The sediments were dominated by clay, detritus, sand and silt; samples taken from below the surface were not blackened and appeared to be well aerated. A moderate amount of bank erosion (10-50 metres) was noted due to stock damage and silt deposits to five centimetres deep were recorded from the middle of the channel.
The only aquatic plant growing in the channel and on the water’s edge were a few patches of Common Reed (Phragmites). Introduced terrestrial grasses dominated the vegetative cover in the channel.
The very narrow riparian zone consisted of a few gum trees over introduced grasses. The surrounding vegetation at the site was grazing land with little remnant vegetation remaining in the landscape.
Special environmental features
Pressures and management responses
|Drought||Through ground and surface water allocation planning and the South East Regional NRM Plan water affecting activity permit process the NRM Board seeks to manage water for environmental, social and economic purposes in a range of climatic scenarios.|
|Livestock have direct access at the site and upstream, causing sediment erosion and adding excessive nutrients (which leads to habitat disturbance, algal growth and aquatic weeds).||The South East NRM Board supports targeted projects that provide opportunities for landholders to access grants for fencing for stock exclusion from time to time for priority catchments.|
|Limited riparian zone vegetation at the site and upstream, providing minimal buffer protection from catchment landuses (reducing habitat quality).||The South East NRM Board assists landholders to access targeted grant opportunities for revegetation and ecosystem protection when funding is available. The Board also works closely with landholders consistent with the Board’s Regional Pest Management Plan to control weeds on their property and to assist in halting their spread to other properties.|