Clyde River Floodplain Risk Management Study & Plan

Council received grant funding from the Australian Government's Preparing Australian Communities Program – Local Stream to undertake the Clyde River Flood Study and Floodplain Risk Management Study and Plan to investigate the flood risk within the catchment.

The primary study area is the 50km reach of the Clyde River from upstream of the Yadboro River confluence through the localities of Yadboro, Mogood, Morton, Brooman and Currowan to the southern boundary of the Shoalhaven City Council LGA at the confluence with the Currowan River.

This stretch of the Clyde River comprises of large areas of land owned by the NSW National Parks and Wildlife Service (NPWS) and State Forests of NSW, but with private land tenures along the river length. The focus of the flood study is predominantly privately owned land and public roads but investigating the full 50km reach length is necessary to better understand flow times and discharge relationships between different waterway crossings over the Clyde River. The catchment includes properties that quickly, for an extended period, become isolated due to inundation of existing low-level waterway crossings.

This project is being undertaken in accordance with the NSW Flood Prone Land Policy, the NSW Flood Risk Management Manual (2023) and in close collaboration with the NSW State Emergency Services (SES), the NSW Department of Climate Change, Energy, the Environment and Water (DCCEEW), and other agencies and stakeholders as required.

Council has engaged a consultant, Rhelm, to assist with the preparation of the Clyde River Flood Study and Floodplain Risk Management Study and Plan. This study will improve Council’s understanding of flood behaviour and impacts on the community, and better inform management of flood risk in the study area.

Project Objectives

The objective of this study is to improve understanding of flood behaviour and impacts, and better inform management of flood risk in the study area in consideration of the available information, and relevant standards and guidelines. It aims to provide an understanding of flood behaviour and consequences in the study area across the full range of potential flood events from frequent to extreme. It involves the consideration of the local flood history, available collected flood data, and the development of hydrologic and hydraulic models.

The project also allows testing and investigating practical, feasible and economic management measures to treat existing, future and residual flood risk. The Floodplain Risk Management Study will provide a basis for informing the development of a Floodplain Risk Management Plan. The plan will document the decisions on the management of flood risk into the future. The plan will also outline a range of measures to manage existing, future and residual risk effectively and efficiently, using the investigations undertaken as part of the Floodplain Risk Management Study. This includes a prioritised implementation strategy, that details how and when measures can be implemented.