TUFLOW Hydraulic Modelling

TUFLOW Hydraulic Modelling

Mid-Semester Assessment Task (Week 5)

6534010059400

www.tuflow.comwww.tuflow.com/forumwiki.tuflow.comTable of Contents-2438401378585Student Name:Student ID:4000020000Student Name:Student ID:Contents TOC o "1-3" h z u Contents PAGEREF _Toc106891239 h 1-11Background PAGEREF _Toc106891240 h 1-21.1Introduction PAGEREF _Toc106891241 h 1-21.2Subject Study Area PAGEREF _Toc106891242 h 1-21.3TUFLOW Flood Model PAGEREF _Toc106891243 h 1-32Assessment Tasks PAGEREF _Toc106891244 h 2-52.1Task 1 Design Event Model Update and Output PAGEREF _Toc106891245 h 2-52.2Task 2 Future Climate Change Assessment PAGEREF _Toc106891246 h 2-62.3Task 3 General Hydraulic Modelling Questions PAGEREF _Toc106891247 h 2-83Marking Breakdown PAGEREF _Toc106891248 h 3-11

BackgroundIntroductionThis course has two set assignment tasks for the semester.

Assessment 1 has been scheduled for Week 5. It tests key concepts taught during the Week 1 to Week 4 tutorials.

Assessment 2 has been scheduled for Week 10. It covers knowledge gained from Week 1 to Week 9, though with a greater focus on the material from Week 5 onwards.

Subject Study Area

A new model location has been provided for this assessment. The hypothetical catchment for this assessment is a tidally influenced floodplain and riverine system. A TUFLOW model of the lower catchment has already been developed for the study. The model includes two ocean water level (tide) boundaries and two external catchment inflows. For this assessment the major inflow is called Main River. The smaller inflow is called Tributary Creek.

TUFLOW Flood ModelA TUFLOW model of the study area already exists, available from the following location: Week_05_AssessmentTUFLOW.

This model has been modified from a Floodplain Management Association benchmark dataset for the purpose of this course (https://wiki.tuflow.com/index.php?title=FMA_Challenge_2). It has been selected specifically because it has been configured to allow modellers to use it without requiring a formal licence. The model will only run licence free if the following model commands remain unchanged:

Demo Model == ON is specified in the TCF

The domain Origin == 1640, 885 and Orientation Angle == 0.0

Cell Size == 30; and

Grid Size (x,y) == 9720, 18305

DO NOT change any of these commands. Doing so will compromise the Demo Model licence free state.

Similarly, it is necessary that the model coordinate reference system remain as NAD27 / California Albers EPSG:3309 for the Demo Model licence to function.

Note: Although the source data is based on information from Californian, the model uses SI units (i.e. metres, not feet).

The project model has been configured to run the 1% Annual Exceedance Probability (AEP) and Probable Maximum Flood (PMF) events. The TUFLOW Control Files (TCF) for these events are found in the Week_05_AssessmentTUFLOWruns folder and titled:

1% AEP event = AS_Q100_Base_001.tcf

PMF event = AS_QPMF_Base_001.tcf

A batch file (_run_AS_001.bat ) has been provided to run these simulations consecutively. The model should each take approximately 15 minutes to complete their simulation on an average performance computer.

Note: Annual Exceedance Probability (AEP) refers to the probability of a flood event occurring in any year. The probability is expressed as a percentage. For example, a large flood which may be calculated to have a 1% chance to occur in any one year, is referred to as a 1% AEP event. In the media, flood events are often referred to by their 1 in X chance of occurring. The list below translates numerous AEP events to 1 in X chance terminology:

0.5% AEP = 1 in 200-year chance flood event. Very Rare flood event classification

1% AEP = 1 in 100-year chance flood event. Rare flood event classification

2% AEP = 1 in 50-year chance flood event. Rare flood event classification

5% AEP = 1 in 20-year chance flood event. Rare flood event classification

10% AEP = 1 in 10-year chance flood event. Frequent flood event classification

The Probable Maximum Flood (PMF) is the largest flood that could reasonably be expected to occur in a catchment based on the Probable Maximum Precipitation (PMP). The theoretical definition of the PMP is the greatest depth of precipitation for a given duration meteorologically possible for a given storm size area at a particular location, with no allowance made for long-term climatic trends

The provided batch file requires the following folder structure to function. Please duplicate this structure on your computer. Do not move the Software folder to a different location. It will break the specified path to the TUFLOW executable in the provided batch file.

48268413609855Source: BMT

0Source: BMT

Assessment TasksBased on the information above and the knowledge you have gained by undertaking the tutorial workshops to date, complete the assessment tasks below. Document your results in the fields / area provided. Also provide digital files of your results when requested (provide ONLY the files requested, not the entire modelling project folder).

Task 1 Design Event Model Update and OutputModels have already been created for the 1% AEP and PMF events. Additional boundary condition input has been provided for numerous other events in the Boundary_Condition_Data.xlsx file within the Week_05_AssessmentData folder.

Update the flood model and simulation batch file to run the 10% AEP, 1% AEP and PMF flood events.

Run the three design flood events and answer the following questions:

Attach your 10% AEP event simulation TUFLOW Log File (*.tlf) with your assessment submission. This file will be reviewed to confirm whether you have updated the model correctly for the 10% AEP event simulation.

So the assessor can easily locate the requested file, list its name here:

(Value = 3 Marks)

Report the maximum flood flow for the Plot Output locations already included in the model:

Table SEQ Table * ARABIC 1Maximum Flood Flow Results (m3/s)

Location 10% AEP Event 1% AEP event PMF event

PO3 PO4 List results to zero decimal place. Rounding mistakes will be marked wrong

(Value = 6 Marks)

Report the maximum flood level for the Plot Output locations already included in the model:

Table SEQ Table * ARABIC 2Maximum Flood Level Results (m)

Location 10% AEP Event 1% AEP event PMF event

PO3 PO4 List results to one decimal place. Rounding mistakes will be marked wrong

(Value = 6 Marks)

Assessment Advice

When updating the TUFLOW simulation files, a logical and consistent naming convention is useful to maintain clarity when many (sometimes tens to hundreds of simulations) are needed to complete a project). AS_Q010_Base_001.tcf would be a logical name to label the new simulations you are creating.

The TUFLOW Log File (*.tlf) will be written to the TUFLOW/Runs/log folder

Refer to Week 4 notes for boundary condition update information.

Refer to Week 2 for Plot Maximum / Minimum result information within the <run id>_POMM.csv files.

If you alter the provided folder structure it will break the executable path reference in the provided batch file. You can create your own batch file based on information from the TUFLOW Wiki: https://wiki.tuflow.com/index.php?title=Run_TUFLOW_From_a_Batch-fileTask 2 Future Climate Change AssessmentCouncil has requested a climate change assessment be completed. 2050 climate change projections for this study area have been defined by:

0.4m increase in sea level (downstream tide boundary); and

10% increase in catchment flow (upstream flood inflows).

Create a new version of the 1% AEP event model by updating the models boundary conditions to accommodate for the above climate change projections. Update your batch file and run the simulation to answer the following questions.

Attach your TUFLOW Log File (*.tlf) with your assessment submission. This file will be reviewed to confirm whether you have updated the model correctly for the 2050 climate change event simulation.

So the assessor can easily locate the requested file, list the names here:

(Value = 4 Marks)

Report the maximum flood flow for the Plot Output locations already included in the model:

Table SEQ Table * ARABIC 1Maximum Flood Flow Results (m3/s)

Location 1% AEP Event 2050 Climate Change

PO1 PO2 PO7 List results to zero decimal place. Rounding mistakes will be marked wrong

(Value = 3 Marks)

Report the maximum flood level for the Plot Output locations already included in the model:

Table SEQ Table * ARABIC 2Maximum Flood Level Results (m)

Location 1% AEP Event 2050 Climate Change

PO1 PO2 PO7 List results to one decimal place. Rounding mistakes will be marked wrong

(Value = 3 Marks)

Plot Outputs are a useful TUFLOW feature for plotting time series results for post-simulation analysis to better understand the flood behaviour and communicate assessment findings to stakeholders. Load your existing climate and 2050 climate change 1% AEP event results into QGIS and present a TUFLOW Viewer graph displaying the timeseries water level results at Location PO3.

An example plot is presented below (note, this is for a different location and event to the scenarios targeted in this question).

Tip: After opening the result dataset in QGIS and TUFLOW Viewer, select the <simulation>_Plot_P in the QGIS Layer Panel. It contains the point object reporting the water level information at Location PO3. Also select, Timeseries = Level from the TUFLOW Viewer Result Type options.

(Value = 2 Marks)

Task 3 General Hydraulic Modelling QuestionsIf a TUFLOW model does not initialise successfully list the seven-step process how to debug errors.

(Value = 7 Marks)

Describe the difference between grid (*.asc or *flt) results and map output (*.dat or *.xmdf) results.

(Value = 4 Marks)

List the file extensions for the following TUFLOW Control Files:

TUFLOW Control File =

Geometry Control File =

ESTRY Control File =

TUFLOW Boundary Control File =

(Value = 4 Marks)

TUFLOW requires all GIS file inputs use a consistent GIS Projection / Co-ordinate Reference System (CRS). Define what a GIS Projection / Co-ordinate Reference System (CRS) is?

(Value = 2 Marks)

By default, every grid cell in a TUFLOW model will be set as active, thus TUFLOW will allow water to flow anywhere within the extents of the 2D domain (depending on the topography and hydraulic conditions). To reduce output file sizes and simulation run times, permanently dry inactive areas can be removed from the computations using TUFLOW Code commands:

What is the "Code value for active cells?

What is the "Code value for inactive cells?

(Value = 2 Marks)

Mannings n is used to define landuse roughness in a flood hydraulic model. Using the resources referenced in the Week 3 tutorial notes, define Mannings n values for the following vegetation examples:

Vegetation Description Image Mannings n value ?Overbank vegetation consists of tall truck trees, no low branches, or shrubs. Tree spacing of approx. 8 metres Answer:

Irregular mountain creek with flexible understorey plants, few vines or woody shrubs. Answer:

(Value = 2 Marks)

When a modeller is developing a flood model choosing an appropriate 2D cell size is an important decision. The 2D cell size should be sufficient in the area of interest to adequately represent the scale of topographic features and flow phenomena being modelled. Using the resources referenced in the Week 3 tutorial notes, if flow within a channel is a key hydraulic feature being modelled, how many grid/mesh elements should be defined laterally across the channel?

(Value = 2 Marks)

Marking BreakdownQuestion Maximum Available Marks Marks

1 3 2 6 3 6 4 4 5 3 6 3 7 2 8 7 9 4 10 4 11 2 12 2 13 2 14 2 Total / 50