Jeff, Great question. The water levels are the heads at position of the screen. The water flows down and up, so there must be a vertical hydraulic head gradient. This causes the heads at depth to differ from the water table. The downward flow in upland areas causes the head in deep piezometers to be lower than the water table, for example. Larry
For an aquifer (subsurface flow), it is not clear to me how the formation (medium through which the water flows) plays a role in the calculation of total hydraulic head. How does the calculation of total hydraulic head for, say, a clay soil aquifer differ from that of a sandy soil aquifer? Is there no obstruction to flow as a result of the soil type, e.g. a clay soil rendering more obstruction than a sandy soil, thereby impacting upon the value of the hydraulic gradient? My question may have to do with the velocity head in groundwater (will it be approx 1 m per day in both clay and sandy soils?)
Thank you so much for this video, it really helped me understand the concept. However I do have a question, if the well screen in Well B was closer to the surface, would the elevation head change and if so why would it do that? Thank you.
This is a great and informative video.
From the Faculty of Agriculture and Environment, Rehovot, Israel,
Thank you!
Excellent run through. Looking forward to watching your other videos.
This was fantastic. Thank you very much. Out of curiosity, at 20:10, why don't all the well levels match the water table?
Jeff, Great question. The water levels are the heads at position of the screen. The water flows down and up, so there must be a vertical hydraulic head gradient. This causes the heads at depth to differ from the water table. The downward flow in upland areas causes the head in deep piezometers to be lower than the water table, for example. Larry
Thank you very much for all the efforts of making all these awesome video tutorials !!
Very well explained, finally understood the meaning of hydraulic head, thank you :)
For an aquifer (subsurface flow), it is not clear to me how the formation (medium through which the water flows) plays a role in the calculation of total hydraulic head. How does the calculation of total hydraulic head for, say, a clay soil aquifer differ from that of a sandy soil aquifer?
Is there no obstruction to flow as a result of the soil type, e.g. a clay soil rendering more obstruction than a sandy soil, thereby impacting upon the value of the hydraulic gradient?
My question may have to do with the velocity head in groundwater (will it be approx 1 m per day in both clay and sandy soils?)
Can you say that hydraulic head is the energy per unitweight of water?
excellent video!
Thank you! This video helped me with my final assignment.
Thank you so much for this video, it really helped me understand the concept. However I do have a question, if the well screen in Well B was closer to the surface, would the elevation head change and if so why would it do that? Thank you.
how would you know the value of Ep to find z ?
How do we pick the datum?
The datum is arbitrary. Usually you would pick the datum below the heads you want to characterize, so the head values are positive.
Thanks!
And what are the answers to the 4 practice problems at the very end?
Thank you sir
thanks a lot