Subject: River Simulation Posted: 7/15/2014 Viewed: 31696 times
Hi, I am doing a research in the Blue Nile river basin from Lake Tana in Ethiopia till Khartoum city in Sudan. I tried to simulate the flow at Eldeim station (gauge station) by choicing Inflow to Area - River - Streaflow Relative to Gauge (Absolute), after running the model. knowing that there are 13 triebutaries above this station. where I add headflow for each of these tributaries.
When I add the headflow for the first one (above lake Tana reservoir) this will remain till Eldeim station, whithout adding the other tributaries (12) for the simulation. Please advice
Dr. Devaraj de Condappa
Subject: Re: River Simulation Posted: 7/16/2014 Viewed: 31657 times
Dear Mohamed,
I am sorry, I don't understand your question. Would you mind to reformulate it?
Thanks!
Eng. Mohamed Abbas
Subject: Re: River Simulation Posted: 7/20/2014 Viewed: 31636 times
Dear, Devaraj
Many thanks for willing to help .. really I edit headflow data for each tributaries (i.e. 13 tributaries)all these tributaries join the main river at different locations including the first tributaries comprising the main river, But when I click a right click on the main river (after connection of all tributaries) and select edit data headflow I noticed the file was not the sum of all these tributaries but was only the first one at the head of the river that I edit it. Am I right, or there was an error.
Dr. Devaraj de Condappa
Subject: Re: River Simulation Posted: 7/20/2014 Viewed: 31626 times
Dear Mohamed,
Ok now I understand your question.
What you are seeing is normal. Headflow is the flow at the head of the river. So if you are looking at the main tributary the headflow is indeed the flow at the head (= beginning) of the river, the one you entered initially and WEAP does not change it.
What you are looking for is actually not the headflow but the flow downstream, after all the tributaries have joined the main river. This flow you can only view it in the Results view (ie WEAP has to run), under Supply and Resources > River > Streamflow. Make sure you select the result for the main river and select the node after the last tributary has joined the main river.
Kind regards,
Eng. Mohamed Abbas
Subject: Re: River Simulation Posted: 7/21/2014 Viewed: 31617 times
Dear, Devaraj
Thank you very much for your assistances.
Yours,
Mohamed
Miss Anum Dar
Subject: Re: River Simulation Posted: 7/24/2014 Viewed: 31532 times
Hi Devaraj,
I read your reply to Mohammed. I have a question, perhaps you can also help me. I have modelled a river in Alberta along with its tributaries and have also added the demand sites. Now I can see the results of water demand, supply requirement, unmet demand, coverage etc. but how can I tell anyone that this much amount of water is there in the river after satisfying all the demand sites? Is there an option in results to see the remaining water available in the river?
Anum
Dr. Devaraj de Condappa
Subject: Re: River Simulation Posted: 7/24/2014 Viewed: 31525 times
Dear Anum,
Yes you can see this with the same Streamflow results I told Mohamed to look at. On your schematic, look at the name of the nodes on the river that WEAP creates for each transmission link from the river to the demands. Then in the Streamflow results search for these nodes and there you can view the flow before and after these nodes.
Kind regards,
Miss Anum Dar
Subject: Re: River Simulation Posted: 7/25/2014 Viewed: 31497 times
Hi Devaraj,
Thanks for your reply. I have one more question: I have a demand site with the name "Petroleum" and it has sub-branches as shown below:
Now I want to provide water to these sub-branches by three different rivers. For more simplicity, I would say that I want to provide water to sub-branch "surface mining" and "atha" by Athabasca river, to sub-branch "peace" by peace river and to sub-branch "cold lake" by cold lake. Is there any option in WEAP to do it? I mean by giving percentages of how much the total annual activity of a demand site is to be met by which river?
Anum
Dr. Devaraj de Condappa
Subject: Re: River Simulation Posted: 7/26/2014 Viewed: 31491 times
Dear Anum,
Yes there is a way:
1. Connect your Petroleum water demand to all the water supply sources (Athabasca river, peace river and cold lake).
2. Right click on the transmission link from Athabasca river and select Edit Data > Maximum Flow Percent of Demand. Entere here the % you want and do the same for all the transmission links.
3. If you are quite familiar with WEAP, you can be fancy with the following options:
* you can enter a monthly % as a function of the sub-branch (i.e., surface mining, different in-situ categories);
* I would advise you to use the Expression Builder and use Branches to ask WEAP to use the values you entered for the 'Annual Activity level' and the 'Monthly Variation' of the sub-branches of the Petroleum water demand. Like this you just need to enter values in the sub-branches of Petroleum water demand and it will automatically reflect in the transmission links (e.g., you would consider scenarios where you are changing the Petroleum water demand);
* in any case, don't forget to check that at every time step the % you entered for Maximum Flow Percent of Demand sums to 100% accross all the transmission links.
I hope my explanations are clear enough. Please tell me if not the case.
Kind regards,
Miss Anum Dar
Subject: Re: River Simulation Posted: 7/29/2014 Viewed: 31458 times
Hi Devaraj,
I tried doing it in the way you told but was not successful. I have some confusion. The sector is:
Let's say for insitu, I want the water from the two river sources: Athabasca and Peace river. If I will use "Maximum Flow Percent of Demand" then do I have to calculate the percentage of each sub-sector (bitumen extraction and then its sub-sectors: surface mining and insitu and also Gas/Chemical Plants) in the petroluem sector for Athabasca and then put that percentage in the Maximum Flow Percent of Demand?? If yes, how will I calculate the percentage of each as it is annual acitvity dependent which keeps on changing every year?
I am not good with expression builder so I have no idea of how to utilize that in my case. Need your assistance.
Anum
Dr. Devaraj de Condappa
Subject: Re: River Simulation Posted: 7/30/2014 Viewed: 31452 times
Maybe in your case it is better that you create more than just one main water demand. I would advise you to do it based on the geographical location of each sub-category (e.g., one water demand for Bitumen Extraction, one for Surface Mining etc).
Kind regards,
Miss myat mon
Subject: River Simulation Posted: 2/6/2018 Viewed: 15265 times
Hello,
I would like to ask about my case. In my case, there have 5 stations from upstream to downstream along the river that I considering. I have temperature, rainfall and discharge data for each stations. I used the streamflow gauge and put discharge data for 5 stations. I would like to know about headflow of the river. How could I calculate and take the headflow from these data?
Thank You
Ms. Stephanie Galaitsi
Subject: Re: River Simulation Posted: 2/6/2018 Viewed: 15260 times
Dear Myat,
If you would like to use your temperature and precipitation data to produce the headflow of the river, you can use a hydrologic model. There are different types of hydrologic models in WEAP - you will pick which one you want when you build a catchment node and go to the data view. Note that you will need additional data too, although the additional data you'll need will depend on the hydrologic model that you select.
You can read about the models in the Help Menu, or the WEAP tutorial (available www.WEAP21.org/tutorial ) has a chapter about hydrology.
Ms. Jacquelin Montoya
Subject: Re: River Simulation Posted: 12/13/2019 Viewed: 11299 times
Dear Dr. Devaraj de Condappa,
I am trying to view the observed vs the simulated gauge, and have applied just the procedure you mentioned:
Supply and Resources > River > Streamflow
It appears correctly the observed gauge vs the simulated gauge or "Reach", for some rivers.
However, for the main river it appears only the observed data and not the simlulated ("Reach"). Could you please tell me with is the issue here?
Mr. Doug Chalmers
Subject: Re: River Simulation Posted: 2/5/2025 Viewed: 814 times
If you do not see both the modeled and observed streamflow in the results for Streamflow Gauge Comparison, then your results are either identical and overlapping, or you have values of 0 for one of the parameters. Check the Table view of the results to be sure.
Eng. Selam Sahlu
Subject: Re: River Simulation Posted: 3/10/2025 Viewed: 381 times
Dear Doug,
I encountered the same issue recently. When I view the results for the Streamflow Gauge Comparison near the head flow, the simulation shows zero. However, when I check the Streamflow Gauge Comparison further downstream, I see a non-zero value for the simulated flow. I used automatic catchment delineation to run the hydrological model.
I would be grateful if you could help me understand what might be causing this discrepancy and how to resolve it.
Best regards,
Selam
Mr. Doug Chalmers
Subject: Re: River Simulation Posted: 3/10/2025 Viewed: 370 times
Selam,
To diagnose the model, go to your streamflow results for your river, and select All Nodes and Reaches at the bottom. It is easiest to isolate the results to one timestep at a time. From here, you can see the nodes along your river where you have flow coming in or out. The names of these nodes correspond to where objects intersect your river- you can hover over the nodes in the schematic to see their names.
Is it possible that your inflows to your river occur slightly downstream?
-Doug
Eng. Selam Sahlu
Subject: Re: River Simulation Posted: 3/12/2025 Viewed: 326 times
Dear Doug,
Thank you for your response with constructive solutions. It helped me. However, I have some questions related to this.
As you recommended, I inspected the results for all reaches and nodes. I then noticed that both my headflow and the next reach have no flow. Additionally, the inflows to the river occur slightly downstream.
In our model, the upstream flow originates from a lake, with multiple tributaries contributing to its inflow. There is also a diversion structure for hydropower that extracts water from the lake, while the remaining flow continues toward the main river. A gauge is located at the lake's outlet to measure the flow entering the main river, which is the primary focus of my analysis.
My questions are as follows:
1. When delineating the catchment, I want to define a catchment that captures the flow from the lake. Where should I place the pour point to ensure accurate flow representation?
2. Where should I position the flow gauge for calibration?
3. How can I model the flow that is diverted for power generation?
4. Is it necessary to define headflow to model this system, or is catchment delineation sufficient for generating streamflow in the river?
I would greatly appreciate any guidance on these questions. Thank you!
Selam
Mr. Doug Chalmers
Subject: Re: River Simulation Posted: 3/18/2025 Viewed: 147 times
Selam,
To answer your questions-
1-2: You will want to place the relative location of your streamflow gauge object in relation to your other model objects the same in your model as in real life. In this case, it sounds that you would place the streamflow gauge just downstream of your lake and the hydropower diversion.
Assuming that the streamflow gauge is located very shortly downstream of the hydropower diversion, I would set your catchment pour point location at the streamflow gauge. Just make sure that your runoff/infiltration link bringing inflow from your catchment brings in the water above the hydropower diversion point. If there are any upstream demands, you would have to either place the runoff/infiltration link upstream of this point or build a separate catchment with a pour point immediately upstream of the upstream demand diversion.
3: If only some of your lake flow is used to generate hydropower, then I would build a diversion object off your river or reservoir at the lake location, then build a run-of-river hydro object on this diversion. The diversion may go back into your river downstream afterwards, depending on how this area is setup in real-life. In order to allocate flow through this object, you'll either have to enter an energy demand and energy demand priority into your hydropower object, or use a minimum flow object on your diversion.
4: Will your catchment cover the entire contributing drainage area to your lake? If so, then you can just use your catchment inflow (note that you'll have to calibrate the inflows). A headflow would be entered only if you have existing time-series data of inflows.
