Likely to be enriched with nutrients when wet due to the surrounding land uses
Riparian vegetation limited and consisting of a few native gum trees over introduced grasses
Site resembles more of a wetland habitat than a channelised stream or drain from the region
Area map
About the location
Reedy Creek-Wilmot Drain is a small drain in the lower South East with a catchment area of about 14 square kilometres. It flows in a north-westerly direction where it eventually discharges into Drain L.
Reedy Creek-Wilmot Drain is an artificially constructed drain where the primary function is to remove surface water and draining saline groundwater to improve agricultural productivity in the region (Department for Water 2010). Given its artificial character, the drain is not expected to be in a highly rated aquatic ecosystemcondition, although it does provide significant habitat for many aquatic species in the region.
The major land uses are grazing and cropping, and there are also patches of remnant native vegetation in conservation parks and adjoining swamp habitats. The monitoring site was located in the upper reaches of the drain off Jorgensons Road, about 28 kilometres north-east from Beachport.
The drain 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 and instream habitat.
Findings
The 18 metre wide creek was dry in autumn and spring 2014, so macroinvertebrate and water quality data were not available for this site.
The sediments were dominated by living and dead detritus, with smaller amounts of sand, gravel and pebble also present. No significant areas of bank erosion were noted and the only animal droppings seen near the edge of the drain were from kangaroos.
The only aquatic vegetation seen in the channel were a few small introduced dock plants (Rumex); no signs of any dried algae were seen during the year, as typically occurs in drying drains in the region, indicating that this drain rarely holds water.
The narrow (<5 metres wide) riparian zone consisted of a few gum trees and wattles over introduced grasses. The surrounding vegetation at the site included areas with native eucalypt and acacia woodland and cleared lands used for grazing sheep and cattle.
Special environmental features
None detected.
Pressures and management responses
Pressures
Management responses
Livestock having direct access (causing sediment erosion and adding excessive nutrients).
Drains have been constructed since the 1860s as an engineering solution to support agricultural development and it is South Eastern Water Conservation and Drainage Board practice to lease drain reserves for grazing in certain circumstances. Not all drains are subject to grazing and leases for grazing are only approved following an engineering and environmental assessment. Lease conditions require the lessee to fulfil pest plant, pest animal and CFS management requirements, thereby relieving the Board of these responsibilities.
Limited riparian zone vegetation (reducing habitat quality, increasing sediment erosion).
The South Eastern Water Conservation and Drainage Board has undertaken a limited revegetation program at key locations, and has the ability to undertake further revegetation works when resources allow. Revegetation at biological hotspots is recognised as a mechanism to reduce nutrient input and soil erosion, and can be undertaken if it does not impede access for management and maintenance.