Summary - City of Gosnells

SummaryiiiCanning River system) and exacerbate adverse environmental impacts. The importance of the restoration ofthe hydrological regime of the area is particularly highlighted by predictions of continuing rainfall decline inthe region and the threat that this poses to regional biodiversity.RecommendationsThis survey provided significant new information about the natural values of the MKSEA that should beconsidered in the planning process. However, there are major shortfalls in the current understanding of thebiological, ecological and physical processes (such as the hydrological maintenance of wetlands; thereproductive strategies, demography and genetics of threatened flora species; and the use of the area by faunaand their migration patterns) and in the definition of the basic habitat requirements of the Threatened Floraand the Threatened Ecological Communities of the area. There have been no threshold values defined for keyvariables (such as the ecological water requirements of Threatened Flora Species and Threatened EcologicalCommunities) that should form the basis of any assessment of the potential effects of various planningscenarios on the important conservation values of the area. Further study into these aspects would berequired to ensure that the proposed rezoning and development of the MKSEA will not contribute to thefurther degradation and loss of environmental values in the MKSEA, BFS 387 and BFS 53.The current survey identified and mapped areas of high conservation significance that should be excludedfrom development and proposed a number of general recommendations to assist in the prevention of some ofthe ongoing current and anticipated degradation and loss of conservation values in the MKSEA, BFS 387and BFS 53. These recommendations (Section 7.1) include the urgent need to implement recovery actions formost of the Threatened Flora Species populations in the MKSEA and the Bush Forever Sites; theenforcement of native vegetation clearing regulations and wetland conservation measures; and theidentification and control of existing land uses that are currently impacting on groundwater quality. Anumber of changes to the management categories of wetlands in the MKSEA are recommended. Appropriatebuffer zones around Conservation and Resource Enhancement Category Wetlands and Ecological LinkageCorridors between high conservation value areas within the MKSEA, BFS 387, BFS 53, the Darling Rangeand Canning River are also proposed and mapped.Three major recommendations are presented below that summarise the most important conclusions of thecurrent survey with regard to the proposed development in the MKSEA.Recommendation 1Given the significant conservation values within and adjacent to the proposed MKSEA and the potential forthese values to be adversely impacted by the proposal, the City of Gosnells is advised of its obligation torefer, for assessment, the proposal to re-zone and develop these rural lands to:• The Federal Department of Environment, Water, Heritage and the Arts (DEWHA) under the statutoryrequirements of the Federal Environmental Protection and Biodiversity Conservation Act, 1999; and• The Western Australian Environmental Protection Authority under the statutory requirements of theWestern Australian Environmental Protection Act, 1986.Recommendation 2The City of Gosnells is advised that further detailed studies are required to understand the hydrogeology ofthe highly water-dependent ecosystems of the MKSEA and the Greater Brixton Street Wetlands and toprovide the data required to remediate the hydrological regime of the area. The scope, methods and lowintensity of the current wetlands survey and the water monitoring programme recently commissioned by theCity of Gosnells are considered insufficient to adequately map the major wetland boundaries, to characterisethe factors that maintain important conservation wetlands in the area and to define the environmental waterrequirements of the remnant native vegetation. Detailed mapping of the Muchea Limestone aquifers of thearea and an invertebrate study of the active Muchea Limestone mound spring in the MKSEA (and possiblyTauss, C. and Weston, A.S. (2010). The flora, vegetation and wetlands of the Maddington-Kenwick Strategic Employment Area.A survey of the rural lands in the vicinity of the Greater Brixton Street Wetlands. Report to the City of Gosnells, W.A. Version 18.04.10