Floodplain Management Study Spring Street Drain, Muddy Creek and Scarborough Ponds - Volume 1

#Objective\r\nThis Floodplain Management Study defines the nature and extent of the flood hazard in the three\r\ncatchments. It also identifies and assesses strategies and measures aimed at reducing the impact\r\nof flooding on both existing and future development, and measures to prevent future development\r\nfrom making flooding worse.\r\n\r\nThe results of this Floodplain Management Study are being used to prepare a Floodplain\r\nManagement Plan (FPMP). The objective of the FPMP is to establish a cost-effective floodplain\r\nmanagement strategy for the area and to recommend a programme for implementation of the Plan.\r\n\r\nThe Study Brief is attached as Appendix A.\r\n#What is in the Study\r\nThe Floodplain Management Study and Plan will not totally eliminate flooding. Flooding is a natural\r\nphenomenon which cannot be fully controlled by human works. In fact, excessive artificial controls\r\nare likely to be very costly and to have adverse environmental effects. Therefore the Floodplain\r\nManagement Study and Plan aim to provide a package of best management practices which give a\r\nbalance between reducing flood hazard and flood damages, allowing appropriate development, and\r\nprotecting and enhancing the environment of the floodplain.\r\n\r\nThis Report has been divided into the following sections:\r\n\r\n* __Section 1__: Introduction (page 1)\r\nEstablishes the context and basis for the plan.\r\n* __Section 2__: Background (page 5)\r\nDescribes the study process, including previous studies, and the background technical\r\ninformation which is available. It includes a review of the previous Muddy Creek Flood\r\nStudies.\r\n* __Section 3__: Existing Flood Behaviour (page 15)\r\nSummarises the available data and modelling results concerning flood behaviour.\r\n* __Section 4__: Social and Economic Impacts of Flooding (page 23)\r\nExamines the potential flood damages and other social and economic effects of flooding for a\r\nrange of flood events, including an extreme flood.\r\n* __Section 5__: Choosing the Designated Flood (page 28)\r\nDiscusses the issued to be considered by Council in choosing a designated flood for\r\nRockdale, and recommends that the 1% AEP flood be adopted.\r\n* __Section 6__: Available Floodplain Management Options (page 35)\r\nDescribes in broad terms the range of flood mitigation and other management works and\r\nother measures available to address the existing, future and residual flooding problems in the\r\nstudy area.\r\n* __Sections 7, 8 and 9__: Options for Management Areas (page 48)\r\nThese three sections describe in detail, for the Muddy Creek, Spring St Drain and\r\nScarborough Ponds catchments respectively, the feasible options and their likely benefits and\r\ncosts.\r\n* __Section 10__: Assessment of Management Options (page 86)\r\nReviews the financial aspects and the justification for the proposed management measures,\r\nidentifies priorities and possible sources of funding. These issues will be further addressed in\r\nthe future Floodplain Management Plan.\r\n* __Section 11__: References (page 90)\r\nTechnical detail which supports the main report is provided in the Appendices, in Volume 2.# 研究目标 本河漫滩管理研究（Floodplain Management Study）明确了三个流域内洪水灾害的性质与波及范围。同时，研究识别并评估了两类措施：一是旨在降低洪水对既有及未来开发项目影响的策略与手段，二是防止未来开发活动加剧洪水风险的相关措施。 本洪水泛滥平原管理研究的成果将用于编制《河漫滩管理计划（Floodplain Management Plan, FPMP）》。该计划的目标是为研究区域制定具备成本效益的河漫滩管理策略，并推荐计划的实施议程。 本研究任务书作为附录A附于本报告后。 # 研究内容说明 本河漫滩管理研究与计划无法完全消除洪水灾害。洪水属于自然现象，无法通过人类工程手段完全管控。实际上，过度的人工管控不仅成本高昂，还会对生态环境产生不利影响。因此，本研究与计划旨在提供一套最优管理实践方案，在降低洪水灾害与损失、保障合理开发，以及保护并改善河漫滩生态环境之间实现平衡。 本报告分为以下章节： * 第1章：引言（第1页）：确立本计划的制定背景与依据。 * 第2章：研究背景（第5页）：阐述本次研究的整体流程，包括既往相关研究情况，以及现有可获取的技术背景资料，其中包含对过往泥泞溪（Muddy Creek）洪水研究的回顾。 * 第3章：现状洪水特性（第15页）：汇总现有关于洪水演进与表现的相关数据及模拟结果。 * 第4章：洪水的社会经济影响（第23页）：针对包括极端洪水在内的各类洪水事件，分析潜在的洪水损失及其他社会经济影响。 * 第5章：指定设计洪水的选定（第28页）：论述地方议会在为罗克代尔（Rockdale）选定指定设计洪水时需考量的各项问题，并建议采用1%年超越概率（Annual Exceedance Probability, AEP）洪水作为标准。 * 第6章：可用河漫滩管理方案（第35页）：概要阐述可用于解决研究区域内现状、未来及残留洪水问题的各类洪水减灾工程及其他管理措施。 * 第7、8、9章：管理分区方案（第48页）：这三章分别针对泥泞溪、斯普林街排水渠（Spring St Drain）以及斯卡伯勒塘（Scarborough Ponds）流域，详细阐述可行的管理方案及其预期效益与实施成本。 * 第10章：管理方案评估（第86页）：梳理拟实施管理措施的财务可行性与合理性依据，明确实施优先级及潜在资金来源。相关议题将在后续正式编制的《河漫滩管理计划》中进一步探讨。 * 第11章：参考文献（第90页）：支撑本主报告的技术细节详见第2卷附录。