Tributary of the Congeratinga River, 1 km east from Second Valley
2011 Aquatic Ecosystem Condition Report
- Dry in autumn and spring 2011
- Likely to be enriched with nutrients when wet due to the extent of grazing in the catchment
- Riparian vegetation consists of introduced grasses and weeds
- Bank erosion and fine sediments characterise this ephemeral watercourse
About the location
Tributary of Congeratinga Creek is a small stream in the Southern Mount Lofty Ranges that rises east from Second Valley and flows north for a few hundred metres before discharging into Congeratinga Creek. The monitoring site was located upstream from ‘Stoney Creek’ off Main South Road, about 1 km east from Second Valley. The major land uses in the 69 hectare catchment are stock grazing and cropping, with minor areas used for roads and remnant native vegetation.
The creek was given a Very Poor rating because the site sampled showed evidence of major changes to both the animal and plant life inhabiting the stream, and a significant breakdown in the way the ecosystem functions. There was considerable evidence of human disturbance including severely degraded riparian habitats and bank erosion due to cattle damage.
The sediments were dominated by sand, clay and detritus, with cobble, gravel and silt also present. Samples taken from below the surface were grey in colour and showed no evidence that the sediments were anaerobic and lacked oxygen. Over 10 m of bank erosion was recorded during both surveys, attributed to cattle damage caused by stock accessing the bed of the stream.
A small growth of rushes (Juncus) was the only type of aquatic plant recorded from the site. The very narrow riparian zone consisted of introduced grasses and weeds, with no trees or shrubs remaining along the creekline. The surrounding vegetation was cleared grazing land with no trees visible in the local landscape.
Special environmental features
Pressures and management responses
|Livestock having direct access at the site and upstream (causing sediment erosion and adding excessive nutrients).||The Adelaide and Mount Lofty Ranges NRM Board’s land management program encourages and promotes managing land to improve water quality. This includes incentives for waterway and wetland fencing to exclude or limit stock from entering riparian zones.|
|Widespread introduced weeds in the riparian zone at the site and upstream (reducing habitat quality).||The Adelaide and Mount Lofty Ranges NRM Board has several pest plant (weed) mitigation and control programs. They work closely with landholders to control weeds on their property and to help stop the spread to other properties and waterways.|
|Limited riparian zone vegetation at the creek and upstream (reducing habitat quality, increasing sediment erosion).||The Adelaide and Mount Lofty Ranges NRM Board’s land management program encourages and promotes managing land to improve water quality. This includes incentives for revegetation programs around waterways and wetlands and stock exclusion as well as educating landholders about the importance of riparian vegetation in managing soil erosion.|
This aquatic ecosystem condition report is based on monitoring data collected by the EPA. It was prepared with and co-funded by the Adelaide and Mount Lofty Ranges NRM Board.