Likely to be enriched with nutrients when wet due to the surrounding land uses
Riparian vegetation consists of River Red Gums over woody weeds and native shrubs
Fine sediment present in the channel but no evidence of bank erosion
Area map
About the location
This creek is a small, first-order stream in the Southern Mount Lofty Ranges that flows for a few hundred metres in a northerly direction into the middle branch of Brownhill Creek, where it eventually joins the other branches to form the one channel towards the northern edge of Brownhill Creek Recreation Park. The monitoring site was located off Wyly Lane, about 1 km west from Crafers West. The major land uses in the 45 hectare catchment are remnant native vegetation and stock grazing, with smaller areas used for conservation, roads and rural residential living.
The creek was given a Fair rating because the site sampled showed evidence of moderate changes in ecosystem structure, and some changes to the way the ecosystem functions. There was evidence of human disturbance including nutrient enrichment promoting the large growth of aquatic plants at the site, and weeds dominated the understorey vegetation on the banks.
Findings
The 2 m wide creek was dry in both autumn and spring 2011. No macroinvertebrate or water quality data was consequently available for this site.
The sediments were dominated by detritus, silt and clay. Samples taken from below the surface were grey in colour and showed no evidence that the sediments were anaerobic or lacked oxygen. No sign of any bank erosion was noted during either inspection.
Over 35% of the channel was covered in rushes (Juncus) but no other aquatic plants or algae were evident at the site. The banks were well-vegetated with River Red Gums over a range of introduced woody weeds (blackberries and broom) and native shrubs (tea tree and wattles). The surrounding landscape consisted of well-vegetated hills dominated by introduced grasses used for sheep grazing.
Special environmental features
None detected.
Pressures and management responses
Pressures
Management responses
Insufficient natural water flows in the creek resulting from water extraction and climate variability (reducing ecological integrity).
Through water allocation planning the Adelaide and Mount Lofty Ranges NRM Board seeks to manage a sustainable water supply for the region so that there is enough water available for everyone (including the environment) even in drought conditions.
Large nutrient inputs to the creek from diffuse sources in the catchment (leading to extensive growth of algae and aquatic weeds)
The Adelaide and Mount Lofty Ranges NRM Board’s land management program encourages and promotes managing land to improve water quality. This includes working with industry and landholders to ensure efficient use of fertilisers and discuss ways to reduce runoff of nutrients into waterways.
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
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