Foreshore Management Plan for the Swan River Estuary in the Western Suburbs of Perth
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Foreshore Management Plan for the Swan River Estuary in the Western Suburbs of Perth For the Western Suburbs Regional Organisation of Councils (WESROC) Seashore Engineering Pty Ltd 25 May 2016 Report SE018-01-Rev0 Document Control Index Author Date Review Date Comment Draft A T. Stul 3.11.2015 Incomplete draft. M. Eliot Excluding sections for CoN, ToMP and Whadjuk Heritage. Sections provided to 14.12.2015 Draft B T. Stul 16.12.2015 V. Cusack 21.01.2016 95% draft T. Stul 8.2.2016 M. Eliot Revised ES. Executive Summaries Draft C T. Stul 28.2.2016 M. McPherson (ToMP) 11.03.2016 Complete draft A. Head (ToC) 9.2.2016 restructured D. Norgard (SoPG) 3.3.2016 M. Goodlet (CoN) 10.03.2016 V. Cusack (WESROC) 16.03.2016 S. Lloyd (Parks and 26.04.2016 Wildlife) Rev 0 T. Stul 25.5.2016 V. Cusack 15.05.2016 Disclaimer (1) The document articulates foreshore management and adaptation approaches recommended by Seashore Engineering. The report is intended to inform, not dictate, future management approaches implemented by foreshore managers. It does not replace the management and decision-making process used by Local Government Authorities (LGAs) that may be influenced by community consultation, financial priorities and the broader scope of LGA management responsibilities. If an LGA selects an alternate management pathway for a site than documented in this report, it is recommended to also update the planned monitoring, capital and maintenance requirements. The opinions contained within the report do not necessarily represent the views of the Department of Parks and Wildlife Rivers and Estuaries Division. (2) From 1 July 2016, any reference to the foreshore managed by the City of Subiaco should be read as managed by the City of Perth following enactment of the City of Perth Act 2016. SE018-01-Rev0 WESROC FMP 20160525 i EXECUTIVE SUMMARY The Western Suburbs Regional Organisation of Councils (WESROC) includes the Towns of Claremont, Cottesloe and Mosman Park, the Shire of Peppermint Grove and the Cities of Nedlands and Subiaco. WESROC works as a voluntary partnership on projects across, or on shared boundaries, and to address cross-boundary regional issues. This Study was commissioned by WESROC, and co-funded with the Department of Parks and Wildlife Rivers and Estuaries Division, to obtain a regional management plan for the 16.1km of estuarine foreshore managed by the councils. The Town of Cottesloe is the only council without estuarine foreshore and therefore not involved in the project. The WESROC foreshore is experiencing problems with erosion and river wall collapse. Estuarine vegetation restoration programs have had varying success. Since 1985, foreshore management in the WESROC area has typically been reactive and on a small scale. Many of the structures installed prior to 1985 by the Public Works Department have reached the effective end of their structural life and require either major repair or changes to management practices. Many of the foreshores have previously been modified by dredging and reclamation, including sand placement to form recreational beaches. Extensive retreat since the mid-1980s has coincided with a policy shift away from dredging. The foreshore has been further impacted by extended periods of high water levels, a number of severe storms and year-to-year variations in the prevailing weather systems, with response also impacted by the extensive previous modifications. This WESROC foreshore management plan (FMP) has been prepared to assist local governments protect and enhance riverbanks. It is intended to assist planning for foreshore structure maintenance, renewal and capital works over a range of time-scales and to help forecast funding needed to undertake the works. The plan attempts to reduce the reliance upon reactive management. Proposed present and future management required consideration of existing management and adaptation pathways, with an aim to develop and improve foreshore resilience. Management recommendations are required at an asset level to facilitate successful delivery of on-ground projects. Approach Physical evidence regarding foreshore dynamics was considered through a vulnerability framework over three time frames. This allowed focus on different elements of management, nominally being: < 5 years which provides a risk management context, by considering the present state of the foreshore and sensitivity to acute events; 5-25 years which indicates management pathways, considering dynamics, life-cycle of existing stabilising structures and actions to increasing foreshore resilience; and > 25 years which provides an adaptation strategy, considering uncertainty related to future management choices and longer-term process variability. Scenarios considered over this scale indicate potential pathways to improve foreshore resilience. Use of the three time frames supported identification of conflicts or constraints between short to medium- term management actions and medium to long term plans or options. Information in this foreshore management plan included actions to improve foreshore resilience over the three time frames, monitoring requirements, issues to be resolved and works that may constrain long term strategies. The study used the segment-scale spatial framework used by the Department of Parks and Wildlife Rivers and Estuaries Division (Parks and Wildlife), with 26 segments in the WESROC area, facilitating ease of communication for Riverbank funding applications. SE018-01-Rev0 WESROC FMP 20160525 ii A key outcome of the evidence-based assessment of dynamics was recognition that much of the observed change was related to previous modifications to the foreshore and existing structures. Within this context, a deeper understanding of the historic decision-making and apparent consequences was developed to support the interpretation of appropriate future interventions. WESROC Foreshore Management and Adaptation Themes Key local themes identified as prevalent along the WESROC foreshore include: Insufficient maintenance; Reactive management; Structures reaching the end of their functional life; Foreshore resilience issues related to surface drainage and irrigation; Trampling by pedestrians and vessel launching/retrieval; Conflicting uses and values; Continued foreshore response to historic works; and The need for improved communication with other stakeholders for foreshore management, asset maintenance and planning, including the Water Corporation and leaseholders. Issues identified relevant to State Government Anticipated foreshore management requirements for WESROC indicate a number of significant issues that are difficult to address at a Local Government level, but may have potential for better or more efficient management through the involvement of State Government agencies. It is recommended that WESROC should engage in strategic discussions with the appropriate organisations, and where appropriate, actively lobby for support using its leverage as a collection of councils. Five challenges were identified with recommendations to address each included below. Interactions with private ownership Existing foreshore management is constrained by interactions with private ownership of land or assets near the foreshore. On foreshores with alternating public and private foreshore ownership, the transfer of stresses due to discontinuous foreshore management obscures responsibilities for management and cost- sharing and potentially causes litigious situations. The issue for private ownership landward of a narrow foreshore reserve is that owners may expect that the LGA will protect their properties at public expense, particularly where it is deemed to provide public foreshore access. Management of these foreshores is further restricted by existing funding arrangements for stabilisation works, which exclude management of privately-owned foreshores. This issue extends to other foreshores around the state and therefore it is recommended that WESROC liaise with the Western Australian Local Government Association (WALGA) regarding up-to-date and effective practices related to private foreshore ownership issues, including a clear understanding of legal positions and obligations. Recommendation: Legal clarification should be sought by WESROC on the relative obligations of LGAs for foreshores with interactions with private ownership and their capacity to obtain funding to support protective efforts (such as Special area rates under Section 6.37 of the Local Government Act 1995). Ceding and vesting of privately-owned foreshore Ceding and vesting of privately owned land by the Western Australian Planning Commission (WAPC) to form a foreshore reserve is triggered by the subdivision process, and often results in high maintenance costs for an LGA due to access constraints and piecemeal treatments; with no improved foreshore access for the public. This is particularly relevant to potential ongoing costs for the City of Nedlands, Town of SE018-01-Rev0 WESROC FMP 20160525 iii Claremont, Town of Mosman Park, Parks and Wildlife and the WAPC. Presently, WAPC will continue to cede land and vest it with an LGA through the subdivision process, and in the context of the Metropolitan Region Scheme (MRS) and Section 152 of the Planning and Development Act 2005. This is supported by the Parks and Wildlife Policy SRT/EA2 on Foreshore Reserves. One possible outcome to reduce this issue is to conduct an MRS amendment at the scale of WESROC. Other LGAs along the Swan and Canning Rivers, as well as coastal LGAs, are similarly