Due in 24hours

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.

Note:

1. Make appropriate assumptions (and list these) regarding the impervious fraction of each sub-catchment area along with the initial losses and continuing losses;

2. Use approximate reach lengths between nodes (and list these) noting that sub-catchment nodes are at the centroid;

3. Use Geelong IFD data (to be obtained from www.bom.gov.au) to estimate the runoff ;

4. Obtain the runoff hydrograph from the entire catchment;

5. 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.

6. 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. Software can be downloaded from: http://www.harconsulting.com.au/software/rorb/

Problem 2

Complete the example application described in Chapter 4 of the HEC RAS User’s Manual Version 4.1 (January 2010) ** this document will be provided.

Software can be downloaded from: http://www.hec.usace.army.mil/software/hec-ras/downloads.aspx

Problem 3

Summarise your work for problems 1 and 2 in a brief and professionally presented report. This report should include an introduction, a summary of all assumptions made, neatly present the important results and also provide some conclusions to your work. The report should be no more than about 5 pages in length.

** Include in your report some discussion around the limitations of both HEC RAS and RORB and suggest some alternative hydrological modelling software that could be used to solve similar types of problems. Specifically include some discussion on the REALM software and also the

Source Software.

REALM - http://www.depi.vic.gov.au/water/water-resource-reporting/surface-water-modelling/resource-allocation-model-realm

SOURCE - http://www.toolkit.net.au/tools/Source%20(public%20version)

Submissions must be made in electronic form