Streamflow

Rivers carved much of the landscape we inhabit, they deposited fertile sediment on the floodplains that we farm, and in many places their flowing water provides power to generate the electricity that lights our homes. This lesson takes a closer look at how water flows through stream systems from small creeks to large rivers. We explain what happens to the water in a stream channel as it travels down the length of a stream from its source to its mouth. We break down how to interpret a Hjulstrom diagram and take a Google Earth tour of the Mississippi River to investigate how discharge changes along its length.
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[@ayanjha7thb802]

Nice teaching sir and madam. Tomorrow is my test and it made me understand. I have liked too

[@Ianhuntercrocker]

You guys rock. Thank you so much for making these videos.

[@hafezahmad3747]

Thank you so much

[@leighwooddudash8925]

It's not clear to me that velocity necessarily increases as you go from headwaters to mouth. Shouldn't that be discharge, not velocity? On the other hand, this is about the best explanation of Hjulstrom diagram I have seen.

[@StephenGSmithers]

Seems logical that velocity would decrease downstream as slope decreases, right? However likely this seems, the data tells a different story for most rivers. Check out this publication from the USGS: pubs.er.usgs.gov/publication/70184457

[@leighwooddudash8925]

Your discussion following that claim of higher velocity downstream is all about discharge, not velocity. You compare Minneapolis, St. Louis, Memphis, and New Orleans. The discussion of sediment grain size at about 2:00, which states big stuff at the headwaters and little stuff at the mouth, implies slower velocity downstream. Again, the discussion of the Hjulstrom diagram is great, better than I have been doing. I know the dynamics are more complicated for a system like the lower Mississippi River, but I want to keep it to the basics for my first-year geology students.

[@GeoscienceImaging]

Velocity of the water is determined by a number of factors. Maybe the most obvious is gradient; higher gradient = faster velocity. That would suggest that headwaters should have faster velocity than downstream areas where the gradient is lower. But there are other factors also: 1) roughness of the channel; 2) total water in the channel; 3) shape of the channel, and more. As you move downstream, these factors all change in ways that increase water velocity - channel gets smoother, more water in the channel, for example. The cumulative effects of these all outweigh the gradient as you go downstream, so in the end, average water velocity is faster downstream than it is upstream.

[@kevincole9062]

A large % of the erois does occure in the downstrean regions -cutbanks etc

[@kylespencer6461]

GEOL 101L anyone?