Georges River Flood Data August 5th-6th, 1986

This report details the flood gauging operation undertaken\r\non 5th and 6th August, 1986 and presents the data\r\ncollected for the Georges River catchment in Sydney.\r\n\r\nThe Georges River catchment area is approximately 960\r\nsquare kilometres and is shown in Figure 2.1. The main arm\r\nof the river begins its course near the Cataract Dam, and\r\nexits into Botany Bay. The main channel is joined\r\nthroughout its course by minor streams and creeks, and also\r\nby the Woronora River; which exits into the Georges River.\r\n\r\nThe catchment area comprises a large part of the south\r\nwestern urban area of the city of Sydney, and the floods\r\nthat have occurred in the catchment have at times caused\r\nsignificant damage to property.\r\n\r\nTo rationalise future development of the area in the face\r\nof potential flood threats, various numerical and physical\r\nmodels have been developed by both the University of N.S.W.\r\nWater Research Laboratory, and the Public Works\r\nDepartment's Manly Hydraulics Laboratory. The success of\r\nthe models in predicting the flooding characteristics of\r\nvarious flood events depend upon collecting specific flood\r\ndata over a series of floods· for model calibration and\r\nverification. To this end, all known information regarding\r\nprevious floods has been documented (Ref. 1), but there is\r\na need for more comprehensive flood data, especially for\r\nmajor floods.\r\n\r\nManly Hydraulics Laboratory's Data Collection Section was\r\nrequested by the Department's Rivers and Ports Branch to\r\nco-ordinate and undertake flood monitoring at various sites\r\nover the area which is being modelled. These monitoring\r\nsites appear in Figure 1.1. A previous report (Ref. 1)\r\ndetails the results of gauging of minor floods undertaken\r\nin 1978 and 1983.\r\n\r\n\r\nFlood gauging on the 5th and 6th August, 1986 was carried\r\nout by personnel from Manly Hydraulics Laboratory, Rivers\r\nand ports Branch and the Water Research Laboratory.\r\n\r\nThe general extent of the flooding can be seen in Plates\r\n1.1 - 1.3.\r\n\r\nThe current metering lines, flood gauge locations and\r\nautomatic recorder locations from which data was collected\r\nare as follows:\r\n\r\ni) Current metering/gauge observations at:\r\n\r\n1. East Hills Footbridge\r\n2. Milperra Road Bridge\r\n3. Mountbatten Bridge\r\n4. Lansdowne Bridge\r\n\r\nii) Automatic recorders located at:\r\n\r\n1. Milperra Bridge\r\n2. Cutler Road, Lansvale\r\n3. Liverpool. Weir.\r\n\r\nData collection from the Irelands Bridge current metering\r\nstation and the Scrivener Street auto recorder is also\r\nspecified under the Georges river flood data collection\r\nprogram, but inaccessibility to the bridge and equipment\r\nmalfunction respectively, precluded data collection from\r\nthese sites on this occasion.

本报告详述了1986年8月5日至6日开展的洪水测流作业，并公布了悉尼乔治河（Georges River）流域采集的相关数据。

乔治河流域面积约960平方公里，如图2.1所示。该河干流发源于卡塔拉克特大坝（Cataract Dam）附近，最终注入植物湾（Botany Bay）。干流沿途先后接纳多条支流与溪涧，其中沃罗诺拉河（Woronora River）亦注入乔治河。

该流域覆盖悉尼西南城区的大片范围，流域内历次爆发的洪水曾多次对当地财产造成严重损毁。

为应对潜在洪水威胁、合理规划该区域未来开发，新南威尔士大学水研究实验室（University of N.S.W. Water Research Laboratory）与公共工程部曼利水力实验室（Public Works Department's Manly Hydraulics Laboratory）已联合开发多款数值与物理模型。上述模型能否精准预测各类洪水事件的水文特性，取决于是否能针对多场洪水采集专项数据以用于模型率定与验证。为此，研究人员已将既往所有洪水相关资料整理归档（参考文献1），但仍需获取更全面的洪水数据，尤其是大型洪水的相关资料。

应公共工程部河道与港口分局的要求，曼利水力实验室数据采集组负责协调并开展研究区域内各监测站点的洪水监测工作，相关监测站点如图1.1所示。此前一份报告（参考文献1）已详述了1978年与1983年开展的小型洪水测流作业成果。

1986年8月5日至6日的洪水测流作业由曼利水力实验室、河道与港口分局以及水研究实验室的人员共同完成。

本次洪水的整体影响范围可见图版1.1至1.3。

本次采集数据涉及的现有流速测线、洪水水位站以及自动记录仪的布设位置如下：

一、 流速测量与水位观测站点：
1. 东希尔斯人行桥（East Hills Footbridge）
2. 米尔佩拉路大桥（Milperra Road Bridge）
3. 蒙巴顿大桥（Mountbatten Bridge）
4. 兰斯当大桥（Lansdowne Bridge）

二、 自动记录仪布设站点：
1. 米尔佩拉大桥（Milperra Bridge）
2. 兰斯维尔卡特勒路（Cutler Road, Lansvale）
3. 利物浦堰（Liverpool Weir）

爱尔兰桥（Irelands Bridge）流速测量站与斯克里夫纳街（Scrivener Street）自动记录仪的相关数据采集任务，原已纳入乔治河洪水数据采集计划，但本次作业中，前者因桥梁无法通行、后者因设备故障，均未能完成数据采集工作。