SURFACE WATER HYDROLOGY
Problem 1
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 10 year ARI using the software RORB.
Figure 1: Rural catchment with sub-catchments and respective areas.
Note:
- Make appropriate assumptions (and list these) regarding the impervious fraction of each sub- catchment area along with the initial losses and continuing losses;
- Use approximate reach lengths between nodes (and list these) noting that sub-catchment nodes are at the centroid;
- Use Ballarat IFD data (to be obtained from www.bom.gov.au) to estimate the runoff ;
- Obtain the runoff hydrograph from the entire catchment;
- 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.
- 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.
Problem 2
Download a copy of HEC-RAS software and its user manual (version 5.0). Complete the example application described in Chapter 4 of the HEC RAS User's Manual Version 5.0 (February 2016).
Submit all of the appropriate project files and results of your work for assessment.
Problem 3
Summarise your work for questions 1 and 2 in a brief report. This report should include an introduction, documentation of any assumptions made, and neatly present the important results. You must also provide a brief conclusions to your work. The report should be about 5 pages including examples of your results, all discussion, a conclusion and any references you may have made.