Subject: Problem specifiying groundwater inflow to river Posted: 2/28/2017 Viewed: 1518 times
I'm having an issue simulating groundwater discharge to the main river in my area.
I currently have it set that the headflow into my river is a constant volume of water per month from one groundwater node, which works fine.
However, when I try to simulate any other discharge from a groundwater node into a lower reach of the river, I get a number of error messages, and numbers that make no sense in my results.
To test what was going on, I reverted back to the last version that worked, and specified an inflow of 0 into a lower section of my river from a groundwater node. This caused a similar set of errors, even though mathematically it shouldn't have made a difference.
Is this a known bug with the software? Is there any work around?
Thanks for any insights.
Subject: Re: Problem specifiying groundwater inflow to river Posted: 3/1/2017 Viewed: 1011 times
Can you tell me a little bit more about the system you're trying to simulate? Does the groundwater come from pumping activities (humans pump up the groundwater), or does it come from an aquifer that naturally seeps water into the river basin?
Have you set it up in WEAP with a groundwater node attached directly (no transmission link) to the different river reaches (e.g. Below River Headflow)?
What error messages are you getting?
Subject: Re: Problem specifiying groundwater inflow to river Posted: 3/16/2017 Viewed: 1012 times
I'm having same situation. In my city, seasons are well defined, so I'm trying to keep the groundwater giving water during the dry season. However, I couldn't do this.
Subject: Re: Problem specifiying groundwater inflow to river Posted: 5/1/2017 Viewed: 1004 times
Do you mean that you want the groundwater to only supply water during the dry season? How have you tried to do this so far?
Subject: Re: Problem specifiying groundwater inflow to river Posted: 6/20/2017 Viewed: 496 times
Yes. During the dry season, the only supply water comes from groundwater. So I have created a transmission link from groundwater (A) to catchment (X), and a runoff/infiltration from this catchment (X) to groundwater (A).
Subject: Re: Problem specifiying groundwater inflow to river Posted: 6/21/2017 Viewed: 492 times
In your first post, you referred to a city, but now you are referring to a catchment. Does the catchment have demand (have you modeled irrigation?). And since we are discussing the catchment now, does it receive water during the dry season?
Subject: Re: Problem specifiying groundwater inflow to river Posted: 7/19/2017 Viewed: 247 times
In my project, a city is supplyed from just one reservoir. So I am trying to model the cacthment envolves this reservoir. In first, I have just created in Weap the main river, because there is a stream gauge in this river near reservoir.
Then, I have created transmission links and runoff/infiltration links to model.
It is a protected area, and there is not agriculture, so the only demand comes from city. As I said before, during the dry season, the only source to river comes from groundwater (water table).
This city does not use groundwater.
Thank you very much.
Subject: Re: Problem specifiying groundwater inflow to river Posted: 7/20/2017 Viewed: 238 times
If the city does not use the groundwater, there are a couple reasons this could be:
1) The city has adequate supply during the dry season from the reservoir.
To check: Look at the city's "Unmet demand" in results - does it have unmet demand during the dry season? Also check if the reservoir is empty during the summer months
2) The groundwater node is empty - is it connected to the same catchment that is supplying the river?
To check: In results, look at the "storage" of groundwater over time.
One way to solve this problem, provided there is adequate water in groundwater, is to specify that during the dry season the city prefers to take from groundwater. You can program this into the "supply preference" of the transmission links to the demand site, using the Monthly Time-Series Wizard. But it would be even better if the supply availability modeled in the groundwater and the reservoir were correct so that the model would already be forced to replicate the real world supply preferences.
Topic "Problem specifiying groundwater inflow to river"