CVEN6005 Advanced Hydraulics And Hydrology :
CVEN6005 Advanced Hydraulics And Hydrology Assignment Brief – Part 1
|Unit||CVEN6005 – Advanced Hydraulics & Hydrology|
|Assignment Weight||25% of unit|
|Issue Date||w/c 27th February 2023|
|Due Dates||23:59, 22nd April 2023 (Part 1A) 23:59, 6th May 2023 (Part 1B)|
|Group Size||Maximum 2 students per group Students completing individually should only attempt Tasks 1-3 and 6-7|
|Staff Member||Johan Vandamme ([email protected])|
Advanced Hydraulics Scenario:
As part of the ongoing development of a large regional town, a drinking water network needs to be analysed and expanded (Part A). In addition, the stormwater design and subsequent flood risk needs to be established (Part B).
There are two submission events for this assignment:
Part A Submission Requirements:
- A brief report (max page count = 6 pages) as a single PDF file – submitted to turnitin
- Your EPAnet model (.net) file – uploaded to the Bb submission page
Part B Submission Requirements:
- A brief report (max page count = 12 pages) as a single PDF file
For both reports, the file should have standard (25.4mm) margins, minimum font size 11. The maximum page count includes any appendices, contents page and/or cover page, but excludes references. Scanned hand calculations, where deemed appropriate, should be neat and clear, and properly signposted (defining variables, equations and solutions where needed). Diagrams must be numbered, clearly captioned and appropriately referenced in text. Written text should be accurate and succinct, with minimal ambiguity or inaccuracy.
Failing to meet the submission requirements detailed above will result in a lower mark being awarded than that suggested by the rubrics given in the assignment.
Late Submission Penalty:
Late submissions will be have 5% removed if submitted from 1 minute to 24 hours after the deadline. Beyond this, an additional 10% is removed per additional day the assignment is overdue. An assessment more than seven (7) calendar days overdue will not be marked and will receive 0%.
This submission assesses the following unit learning outcomes:
- Design and evaluate the hydrologic principles associated with water resources engineering
- Analyse, appraise and design water distribution networks using a variety of industry appropriate methods
Assessment criteria and marking distribution and Engineers Australia competencies addressed The total assessment mark awarded is made up of the marks awarded to each element within the assignment brief. Weightings and marks are given for each section.
Each item of the assessment aligns with certain EA competencies to be demonstrated. Other competencies may be demonstrated by completion of the task in addition to those noted.
|Item||Engineers Australia competencies 1 and (if appropriate) Level of Learning 2||Excellent standard (meets all expectations set out below)||< Competency range > Highest Lowest||Unsatisfactory standard (fails to meet minimum expected)|
|Part A – Water Delivery||Conceptual Understanding Specialist Knowledge Problem Solving Use of Techniques Communication Creativity||Accurate and appropriate analysis Well written and clearly communicated results Design and discussion offering optimised suggestions and clear evaluation of ideas||Inaccurate analysis Poorly written, with unclear communication and badly presented results Design proposals not evaluated or considered against the scenario|
|Part B – Stormwa ter Manage ment||Conceptual Understanding Specialist Knowledge Problem Solving Use of Techniques Systematic Use 3.2 Communication||Accurate and appropriate analysis Well written and clearly communicated results Design and discussion offering optimised suggestions and clear evaluation of ideas||Inaccurate analysis Poorly written, with unclear communication and badly presented results Design proposals not evaluated or considered against the scenario|
Part A (35% of Assignment, Due 22nd April)
An urban area, shown in Figure 1, has some of a water network already built. The condition of the PE pipes can be assumed to be very good, and the steel pipes are known to have a roughness of 0.1mm.
The network is fed by a gravity main 4km to a tank (Tank 1), from which the water is pumped into the network by a variable speed pump (Pump 1). The reservoir has a water age of 8 hours. Due to the complexities of modelling a variable speed pump in EPAnet, the approach taken should be to characterise the pump by a single point pump curve of (150Ls-1, 30m), followed by a pressure reducing valve with a maximum pressure of 35m. The tank has a reduced level of 8m, with a 2m maximum depth and a 22m diameter.
Figure 1 – Existing Water Supply Network
The network demands are shown in Table 1. The flows are split into domestic and industrial flows, where domestic values (𝑄d) given are averages of the daily demand, and industrial values (𝑄i) are peak flow requirements. All nodes shown in Table 1 have a reduced level of 10m.
Table 1 – Network Node Demands (L/s)
The network will need to be expanded by including the following large demand nodes. The new nodes will have a demand depending on your student numbers, as shown in Table 2 – New Network Node Demands (L/s)Table 2. You should ignore the greyed out nodes for your student numbers combination.
|Sum of the last digit from each student ID number1|
|Node||Reduced Level||Node Demand||0 − 7||8 − 12||13 − 18|
Table 2 – New Network Node Demands (L/s)
- Using the EPANET model (available on Bb), identify the issues with the current network, given the expected service provisions are:
- Minimum pressure head of 13m at the nodes (for all times)
- Maximum pressure head of 35m at the nodes (for all times)
- Maximum water age at the nodes of 30hrs
Although the parameters of the network are correct (pipe, nodal values, etc.), the model settings may need to be adjusted to ensure the output of the model is accurate.
- Develop the network to include the required nodes in Table 2 and to overcome any of the issues found in Task 1. You should aim to minimise alterations to the current network but can replace or remove pipes if needed.
No additional source is available, but other tanks can be added to the network if deemed appropriate. You cannot change the pump / pressure reducing valve settings, but may install additional pump(s) using the same combination.
- The client is worried about the possibility that Tank 1 may be contaminated with some toxin. Model the water toxicity (for your finished network in Task 2) at the nodes, if the tank contains 100mg/L of toxin. You may assume that the source is not contaminated, nor is there any initial toxin in the pipe network. Guidelines prohibit a level above 0.2mg/L in the water supply.
The EPANET (.NET) file for Task3 must be uploaded as part of your submission.
It is vital that you use the same node labels as in Figure 1. The accuracy of your report depends on the values provided against nodes being labelled the same as nodes in the figure.
1 If working as an individual, sum the last 2 digits of the ID number.
|Task 1 (7%)||Task 2 (16%)||Task 3 (12%)|
|HD (>80%)||EPAnet model is correctly and efficiently set-up, calibrated and the results are presented clearly. Issues with the current service levels are shown for all the network using an accurate, steady-state model.||Proposal of an excellent design that meets the requirements and maintains the network service levels presented in a cost effective manner. Design is fully analysed across a steady state time period, using a completely accurate, reliable model. Discussion of how the design solves the identified problem(s) and clear evidence of other rejected design ideas.||The full extent of the toxin is modelled through the water network using an accurate, steady state model. The time of the contamination is explored to find a worst-case occurrence. All instances of nodes being above guidelines are identified, and discussion offers additional insight to the modelling method and issues.|
|D (70%- 79%)||EPAnet model is correctly set-up and the results are presented clearly. Issues with the current service levels are shown for all the network using a mostly accurate, steady-state model.||Proposal of a good design that meets most of the requirements across the time period. Design is fully analysed across a steady state time period, using a mostly accurate, reliable model. Discussion identifies the advantages and disadvantages.||The full extent of the toxin is modelled through the water network using an accurate, steady state model. Most instances of nodes being above guidelines are identified. Discussion offers additional insight to the model.|
|C (60%- 69%)||EPAnet model is correctly set-up and the results are presented clearly. Most of the issues with the current service levels are shown for the network.||Proposed design meets the requirements (though perhaps very inefficiently), with a brief evaluative discussion and a mostly accurate, reliable model.||The full extent of the toxin is modelled through the water network using a mostly accurate model. Most instances of nodes being above guidelines are identified.|
|P (50%- 59%)||EPAnet model has been run over a time period that highlights some of the network issues.||Proposal suggests a design that should feasibly meet requirements, though the model may lack accuracy in places.||Model offers some insight and at least some of the above guideline levels are identified.|
|Fail (<50%)||EPAnet model is not run in a manner to provide meaningful output.||Designs do not meet requirements, and/or model accuracy is inadequate.||Toxin is not accurately modelled through the network or output is unclear.|
Part B (65% of Assignment, Due 6th May)
A small airport is being constructed in an undeveloped area. The schematic of the area is shown in Figure 2. The drainage from this airport needs to be designed.
Figure 2 – Schematic of Development
The requirements for the development are that all the impervious surfaces (apron, runway, and building) is to be collected into a retention basin located in the schematic shown (the basin lines up with the South end of the runway). This basin will drain into a river.
The terminal building sheds water from the South to the North edge. Downpipes are spaced every 30m. The capacity of the roof gutters and downpipes (roof plumbing) are outside the scope of this design.
The concrete apron has surface drains spaced according to Table 3, with one of the drains aligned exactly in the centre of the apron.
The runway must shed across its width, and can drain to a swale on one or both sides. The entire site slopes according to the gradient in Table 3, sloping from North to South. You should assume that the runway will follow the site gradient.
Both the runway and the apron are sealed concrete.
|Sum of last digit from each student number1||Roof Gradient||Centre-Centre distance for surface drains in concrete apron||Gradient across site||Maximum (Peak) Discharge|
|0 − 6||4%||80𝑚||0.4%||200𝐿/𝑠|
|7 − 11||2%||60𝑚||0.6%||250𝐿/𝑠|
|12 − 18||1%||40𝑚||0.8%||300𝐿/𝑠|
Table 3 – Site Details
- Design the drainage layout for the site. You will need to choose direction, size (diameter) and gradient of any pipe(s). The cross-section of the swale(s) parallel to the runway will also need to be designed. Gradients and sizes should be calculated for this task for a 20% AEP storm.
- Design the retention pond and outlet structures to ensure that all duration storms (of a 20% AEP) are able to be maintained on site with a maximum discharge as seen in Table 3.
The outlet structure should consist of a single orifice (rectangular or circular) with invert level at the permanent storage level, and an overflow weir provided at a higher elevation. You should specify these levels relative to the reduced level of the southern end of the runway (which is the lowest drained point on the site).
You will need to use hydrological modelling (e.g. Modified PULS), and produce graphs of peak discharge vs. storm duration and water quality volume vs. storm duration for all 20% AEP storms.
|Task 4 (10%)||Task 5 (20%)|
|HD (>80%)||A clear, effective layout that clearly offers economic viability and a brief rationale justifies placements and gradients. Critical times are calculated accurately and presented well. Sizes and gradients are accurate and the design clearly passes the required flow (20% AEP) efficiently and with minimal excavation.||Pond design and outlet sizes are appropriate, with clear explanation for any contentious decisions, and references to scenario where required. Outlet structure meets the flow limit in all cases. Routing methods are clearly explained, with fully accurate, appropriate and relevant methods of routing, including accurate inflow patterns, appropriate relationships between 𝑄 and 𝑆, as well as switching between combined and single outlet. Graphs presented are fully accurate.|
|D (70%- 79%)||A clear and effective layout with appropriate rationale. Critical times are calculated accurately, for the most part. Appropriate sizing and gradients result in acceptable flow conditions.||Pond design and outlet sizes are appropriate. Outlet structure meets the flow limit in all cases. Routing methods are clearly explained, with mostly accurate, and appropriate methods of routing. Graphs presented are accurate.|
|C (60%- 69%)||A functioning layout. Critical times are considered accurately at least once. Sizing and gradients are mostly appropriate.||Pond design, sizes and outlet structure are designed to clearly meet the requirements of the brief. Graphs are mostly accurate, and routing method is explained, though ambiguously at time.|
|P (50%- 59%)||A functioning layout. Gradients, whilst functional, require excessive excavation.||Pond is big enough to maintain the flows from a design storm. Outlet shows some clear indication of meeting the SRD in some storm events. Routing methods are identified.|
|Fail (<50%)||A poor layout that offers incomplete drainage, and/or values (DN and/or gradients) are mostly inaccurate or omitted.||Pond and/or outlet design clearly flawed, or errors in the design result in significant over/under design.|
As part of the planning for the airport, the client needs to present a flood study for the river that the airport drains into. The local authority are worried about a storm event causing flooding of a critical road – where the river passes under the road through a culvert. You need to model this storm to determine if the road is at risk of overtopping.
Figure 3 – Sketch of River and Drain (NOT TO SCALE)
The cross section of the river and the drain are constant and can be seen in Figure 4. The drain can be considered as a straight channel. The river has a constant gradient of 0.2%, and the drain has a constant gradient of 0.8%. The junction between the drain and the river is such that the bank station (top left point) is equal for the river and the drain. The roughness of all the river channel beds can be considered as 0.030 and the drain as 0.035.
The culvert should be considered a ‘tapered inlet throat’ rectangular culvert which is approximately 25m long and has a roughness of 0.05.
Distances and gradient of the river and drain are given in Table 4.
|Sum of last digit from each student number1||A||B||C||D||E||Drain Gradient|
|0 − 9||400m||1.8km||4m||0.7m||3.4m||0.01|
|10 − 13||600m||1.6km||3.5m||1.0m||2.5m||0.01|
|14 − 18||300m||1.4km||3m||0.8m||3.0m||0.015|
Table 4 – Dimensions of river and drain (in m) and gradient (unitless)
Figure 4 – Shape of River, Drain and Culvert
- The Annual Maxima historical flow rate in the river is uploaded to Blackboard (the file is listed in Table 5). You must analyse this flow rate record and demonstrate an appropriately chosen and fitted probability distribution. Having fitted the appropriate distribution, you must determine the flow rates that can be expected in the extreme flow environments of 20% AEP, 10% AEP and 1% AEP.
|Difference between the last digit of each student number1||File Name|
|0 − 1||StreamFlow01.txt|
|2 − 4||StreamFlow24.txt|
|5 − 9||StreamFlow59.txt|
Table 5 – File name for Stream Flow data
- You must develop a model of the river. Using your solutions to Tasks 5 and 6, you must develop a HEC-RAS (or similar) model that can predict the maximum water height (Headwater and Tailwater) and the time this occurs after the start of the storm at the culvert. You can assume that the river runs at a constant flow rate for the duration of the model, and the drain will vary as per the solution to Task 5 (if completing this assessment as an individual, us the sample data on Bb).
You should produce at least 1 graph showing the water height and flow rates plotted against time for the 20% AEP storm event. Higher marks will also need to consider the 10% AEP and 1% AEP storms. You will also need to explain how you modelled this, briefly documenting key decisions and identifying any assumptions, limitations, etc.
|Task 6 (10%)||Task 7 (25%)|
|HD (>80%)||The correct probability distribution is selected, with an accurate and appropriate analysis against a number of valid distributions. The discussion indicates concerns regarding the accuracy and/or validity of the analysis, suggesting appropriate margins of error or tolerances. The distribution is correctly fitted and the flow rates are accurately determined.||A robust and accurate unsteady-state flow model has been completed with HEC- RAS, and the results of water height are clearly displayed and discussed for all inflow from both river and drain of 20%AEP, 10% AEP and 1% AEP storms. The modelling method, including boundary and initial conditions, as well as any assumptions used, are correct, discussed and briefly considered as a source of error.|
|D (70%- 79%)||A valid probability distribution is selected, with a fair analysis against a number of distributions. The discussion indicates concerns regarding the accuracy and/or validity of the analysis.||An unsteady-state flow model has been completed with HEC-RAS, and the results (of water height) are produced with reasonable accuracy and are clearly displayed and discussed. River flow is considered for 20% AEP and at least one other storm, with the drain inflow considered for at least 20% AEP.|
|The distribution is correctly fitted and the flow rates are accurately determined.||The modelling method, including boundary and initial conditions, as well as any assumptions used, are discussed.|
|C (60%- 69%)||Flow rates are calculated by analysing the data against a probability distribution. Some discussion indicates why this probability distribution was used.||HEC-RAS (or another method) has been used, and reasonably accurate height values are given for the 20% AEP storm – despite limitations on the modelling methodology, which may be steady state only.|
|The model/method is discussed and the limitations are identified and discussed.|
|P||Flow rates are calculated to the correct magnitude, with a||HEC-RAS (or another method) has been used, though the accuracy of the method is|
|(50%-||method that stands to reason, though perhaps fails||limited. The report offers a prediction of the river height, though the accuracy is|
|Fail (<50%)||Flow rates are not calculated, or are calculated but are wildly inaccurate.||Weak modelling fails to offer meaningful predictions of the river height.|