Ecological Assessment of the Impacts from Stormwater
Drainage into Ditton Road Bushland Sunnybank Hills
There has been inappropriate use of the Ditton Road Bushland, a small remnant forest of scribbly gum (Corymbia racemosa), and Queensland white stringybark (E. tindaliae), by the intrusion of a large stormwater runoff pipe from an adjoining multi-unit development.
This would appear to be a gross abuse of environmental best practice, that solves their development dilemma by dumping excess runoff into a small remnant, and should be challenged by BCC, who have again failed to provide adequate protection for bushland.
This would seem to be contrary to the Water EPP,.BCC Waterways Policy and Codes. It will increase waterlogging, weeds, litter and sediment. Best practice would be on-site treatment within the development which could include;
Council has failed in its duty to adminster its own policies and protect neighbouring bushland.
The accompanying photograph shows the level of intrusion across an access track and fire easement, tall scribbly gum, bloodwoods and stringybarks, and also has the unusual corkwood (Duboisia myoporoides), which will be affected by the increased runoff.
This impact will cause major changes in the water regime from higher soil moisture levels; and the increased water logging of the larger mature trees adjacent to exit points, may eventually suffer from varying degrees of dieback.
This area has well drained sandstone-derived soils. These soils are very prone to erosion of the top soils and leads to down slope sedimentation, as evidenced on track down the firebreak, and also on the storm water drain on Ditton Road (see photograph).
Some of the more notable plants that would be effected include corkwood (Duboisia myoporoides), forest boronia (Boronia rosmarinifolia), small herbs and ground cover plants such as Christmas orchid (Calanthe triplicata) and hyacinth orchid (Dipodium punctatum).