Sydney Water Corporation Review of Environmental Factors – Bargo Wastewater Scheme Appendix C Ecological Impact Assessments Ref: 433990 January 2013 Final Sydney Water Bargo Wastewater Scheme Ecological Impact Assessment January 2013 This Ecological Impact Assessment (“Report”): 1. has been prepared by GHD Pty for Sydney Water; 2. may only be used and relied on by Sydney Water; 3. may only be used for the purpose of determining the Review of Environmental Factors for the Bargo Wastewater Scheme (and must not be used for any other purpose). GHD and its servants, employees and officers otherwise expressly disclaim responsibility to any person other than Sydney Water arising from or in connection with this Report. To the maximum extent permitted by law, all implied warranties and conditions in relation to the services provided by GHD and the Report are excluded unless they are expressly stated to apply in this Report. The services undertaken by GHD in connection with preparing this Report: x were limited to those specifically detailed in section 1.1 and sections 3.1 and 3.2 of this Report; x were subject to the survey considerations discussed in section 3.2.3 of this Report The opinions, conclusions and any recommendations in this Report are based on assumptions made by GHD when undertaking services and preparing the Report (“Assumptions”), including (but not limited to): x that the Proposal description, including construction methods and mitigation measures described by Sydney Water is accurate and complete x That the Proposal Footprint provided by Sydney Water is accurate and that the proposal will not result in any impacts on the natural environment outside of this area GHD expressly disclaims responsibility for any error in, or omission from, this Report arising from or in connection with any of the Assumptions being incorrect. Subject to the paragraphs in this section of the Report, the opinions, conclusions and any recommendations in this Report are based on conditions encountered and information reviewed at the time of preparation. GHD expressly disclaims responsibility for any error in, or omission from, this Report arising from or in connection with those opinions, conclusions and any recommendations. 1 21/21291/184033 Bargo Wastewater Scheme Ecological Impact Assessment Contents 1. Introduction ......................................................................................................... 1 1.1 Proposal description ........................................................................................................ 1 1.2 Terms and definitions ...................................................................................................... 2 1.3 Site location and layout ................................................................................................... 2 2. Legislative context .............................................................................................. 4 2.1 NSW legislation ............................................................................................................... 4 2.2 State Environmental Planning Policies ............................................................................. 5 2.3 Commonwealth legislation ............................................................................................... 6 3. Methods .............................................................................................................. 8 3.1 Desktop assessment ....................................................................................................... 8 3.2 Field surveys ................................................................................................................. 10 4. Existing environment ......................................................................................... 12 4.1 Landscape context ........................................................................................................ 12 4.2 Flora ............................................................................................................................. 12 4.3 Fauna............................................................................................................................ 16 4.4 Conservation significance .............................................................................................. 22 5. Potential impacts ............................................................................................... 27 5.1 Measures to avoid direct impacts................................................................................... 27 5.2 Direct impacts during Construction ................................................................................ 29 5.3 Indirect impacts during construction ............................................................................... 33 5.4 Operational impacts....................................................................................................... 35 5.5 Cumulative impacts ....................................................................................................... 37 5.6 Key Threatening Processes ........................................................................................... 37 6. Mitigation measures .......................................................................................... 40 6.1 Avoidance of impacts .................................................................................................... 40 6.2 Mitigation of impacts ...................................................................................................... 40 6.3 Offsetting of Impacts...................................................................................................... 43 7. Assessments of significance ............................................................................. 44 7.1 Identification of affected threatened biota....................................................................... 44 7.2 Impacts on threatened biota listed under NSW legislation .............................................. 45 2 21/21291/184033 Bargo Wastewater Scheme Ecological Impact Assessment 7.3 Impacts on MNES ......................................................................................................... 45 8. Conclusions ...................................................................................................... 46 References ................................................................................................................ 48 Table Index Table 1 Key to likelihood of occurrence for threatened biota 9 Table 2 Survey effort 11 Table 3 Vegetation communities recorded in the study area 14 Table 4 Declared noxious weeds of the Wollondilly LGA recorded during the field survey 15 Table 5 Identified constraint classes 28 Table 6 Key threatening processes 38 Table 7 Fauna species list 1 Table 8 Flora species list 1 Figure Index Figure 1 Proposal footprint and ecological constraints (northern section) 2 Figure 2 Proposal footprint and ecological constraints (southern section) 3 Figure 3 Threatened biota and habitat features (northern section)20 Figure 4 Threatened biota and habitat features (southernsection)21 Appendices A Species Lists B TSC Act Assessment of Significance C EPBC Act Assessment of Significance 3 21/21291/184033 Bargo Wastewater Scheme Ecological Impact Assessment 1. Introduction GHD Pty Ltd (GHD) has been engaged by the Sydney Water Corporation (Sydney Water) to undertake a Review of Environmental Factors (REF) for the proposed Bargo Wastewater Scheme (subsequently referred to as the ‘proposal’ for the purposes of this report). The proposal aims to provide improved wastewater services to the subsidised service area of Bargo. The preferred servicing strategy is a pressure sewerage collection system within the Bargo village, transfer of the wastewater to a new WRP located north of Bargo and effluent management via sub-surface irrigation. This Ecological Impact Assessment has been prepared as a supporting document to the REF. It assesses the potential for impacts on ecological values, with particular emphasis on threatened ecological communities, populations and species listed under the NSW Threatened Species Conservation Act 1995 (TSC Act) and Fisheries Management Act 1994 (FM Act), and Matters of National Environmental Significance (MNES) listed under the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act). Mitigation measures to ameliorate potential impacts of the proposal are included in Section 7 of this report. 1.1 Proposal description The proposal footprint is shown in Figure 1 and 2. The proposal would provide a reticulated wastewater service to existing, unsewered urban properties within the subsidised service area of Bargo. The preferred servicing strategy for the Bargo wastewater scheme would involve a pressure sewer collection system for each property with transfer from a new Wastewater Pumping Station (WWPS) via a 2.3 km transfer main to a new Water Recycling Plant (WRP) located 1 km north of Bargo (Figure 1). Following treatment at the WRP, effluent would be discharged via sub-surface irrigation to a land application area. The proposal would include: on-property pressure sewerage system (PSS) equipment to eligible properties within the subsidised service area approximately 16.2km of pressure reticulation a barometric loop approximately 14m high (near the existing reservoir site) a gravity trunk main approximately 1km long connecting the reticulation