CVEN3501 Assignment 2

CVEN3501 - WATER RESOURCES ENGINEERING ASSIGNMENT 2

ASSIGNMENT DUE: 21st MAY 2014, 5:00PM

Please submit in box marked Fiona Johnson on the 3rd floor opposite Room 309 in the Civil and Environmental Engineering Building, with a cover sheet that has your name, student number and workshop class.

Ensure that you show your working and/or summaries of the data that you have used for the calculations. State any assumptions that are required.

Penalty for late submission is 10% per day.

You have been asked to determine design flows for a project located in Thora, NSW (Latitude = -3026', Longitude = 152 47', Elevation = 50 m AHD). The location shown in Figure 1.

The flows from two catchments are to be considered. The first is the full Bellinger River catchment that drains to Thora. There is a streamflow gauge located on the river at Thora. The second catchment is a local sub-catchment draining to the project site. The locations of the main catchment and sub-catchment are shown in Figure 2.

Part 1 (10 marks) a) Using the recorded flow data at the Thora Gauge (spreadsheet on Moodle

and location shown on Figure 2) undertake a Flood Frequency Analysis for the Bellinger River at Thora catchment to determine the peak flow in the 2% AEP flood event.

b) On the log paper (available from Moodle) plot the observed Annual Maximum Series flood values and the design values for the 50%., 20%, 10%, 5%, 2% and 1% AEP events. (Note if you choose do this plot in Excel you must make sure that you use a probability scale for the x-axis. This is different from a log scale.)

Part 2 (5 marks)

A bridge is to be constructed at the outlet of a 27.97 km2 sub-catchment at Thora. This bridge is to be designed for a 2% AEP event. Using the Probabilistic Rational Method, what flow should the bridge designers use?

Part 3 (5 marks)

There are three main software programs used by industry to analyse flood flow in catchments. The programs are: XP-RAFTS, RORB and WBNM. User manuals for each of these programs have been uploaded to Moodle along with some other resources. Based your knowledge from the course lectures, the resources

CVEN3501 Assignment 2

available on Moodle for this assignment and any other sources of information you think are useful:

List the information/data you would need to be able to model the Thora sub-catchment in one of these software programs.

Provide explanations for how each piece of information/data is used or why it is required.

The information/data requirements are not the same for all software so make sure that you are clear in your answer which software you are discussing. Your answer to this question should not need to be longer than half a page long and can be in point form.

Figure 1: Location of Thora (red point)

CVEN3501 Assignment 2

Figure 2: Catchment for Bellinger river and sub-catchment at Thora