This report presents the results of the investigation of flooding in the Burrangong Creek catchment at Young, which has been prepared for Young Shire Council (YSC) with the support of the Office of Environment and Heritage (OEH). The Flood Study provides the basic information on present day flooding conditions for the Floodplain Risk Management Study & Plan (FRMS&P) which is the next stage of investigation in the NSW Government’s Policy for the development of flood prone lands and is presented in a companion report (L&A, 2014). A Data Review and Collection Report (L&A, 2013a) was previously prepared to identify gaps in the data base available for the Flood Study.

The study objective was to define flood behaviour at Young for flood frequencies ranging between 5 and 200 year Average Recurrence Interval (ARI), as well as for the Probable Maximum Flood (PMF). Young is situated in the headwaters of Burrangong Creek, part of the Bland Creek system which drains the southern portion of the Lachlan Valley and flows into Lake Cowal. The total catchment area of Burrangong Creek is 77 km2 at the Sewage Treatment Plant (the downstream extent of the study area), which is located about 2 km downstream of the town.