A hypothetical map for a rural catchment near Ballarat, Victoria is shown in Figure 1. Your task is to estimate the runoff hydrograph at the outlet of the catchment for a 50 year ARI. Figure 1: Rural catchment with sub-catchments and respective areas. Note: ï‚· Make appropriate assumptions (and list these) regarding the impervious fraction of each subcatchment area along with the initial losses and continuing losses; ï‚· Use approximate reach lengths between nodes (and list these) noting that sub-catchment nodes are at the centroid; ï‚· Use Ballarat IFD data (to be obtained from www.bom.gov.au) to estimate the runoff ; ï‚· Obtain the runoff hydrograph from the entire catchment; ï‚· Check for time of concentration, tc, value and if it is unrealistic, adjust the K value in the model noting that the K value can be as high as 50 or 60. ï‚· Provide a graph of the hydrograph you obtain along with a tabular summary of your outputs. Refer to the RORB user’s manual for additional information. Catchment Complete the example application described in Chapter 4 of the HEC RAS User’s Manual Version 4.1 (January 2010). Submit all of the appropriate project files and results of your work for assessment. Problem 3 (4 marks) Summarise your work for questions 1 and 2 in a brief report. This report should include an introduction, document all of the assumptions made, neatly present the important results and also provide some conclusions to your work. The report should be between 5 and 10 pages including results, references etc.