How surface water flows in the US

[BillTre]

Found this map website.
Click on the map somewhere, and it will figure out the path surface water, from that point, would take, as it flows to the sea (or where-ever).
It also makes a 3D fly over if you click the path.

It doesn't show drainage basins, which would have been nice, but there are other maps that do that.

 

[fresh_42]

It doesn't show drainage basins, which would have been nice, but there are other maps that do that.

I dropped at a point in NM and it ended up in the desert!

 

[BillTre]

Some go to no outlet basins (like death Valley).
Some end at the border.
Some may dry up, wonder when they will show this for the Colorado?
Some can just be computed wrong. I got a map of drainage flows in S. Asia and found some errors in the ways the rivers were predicted.

Exchanged messages with the guy who made it and he corrected it and gave me a new copy. These things are computed from map data (GIS, I guess) and I guess errors can arise.

 

[fresh_42]

Some may dry up, wonder when they will show this for the Colorado?

I got the Colorado river when I dropped it in the mountains of Colorado. It's a nice toy, and all my checks were correct.

 

[BillTre]

It stops at the Mexican border, before it gets to the sea, because they don't do Mexico.

 

[fresh_42]

It stops at the Mexican border, before it gets to the sea, because they don't do Mexico.

Yes, but that's only a few miles. The US are easy. They have three parts (Atlantic / Gulf / Pacific), the Rockys are a drainage divide, and Gulf goes up to Canada due to the Mississippi and the Appalaches. Not that complicated.

 

[BillTre]

The area between E. India, Myanmar, China and Thailand is really interesting.
Four major rivers (Ganges, Irrawaddy, Mekong, and Yangtze), running in parallel, pretty close together.
I think this from slow changes in elevations and flow patterns as the India plate was shoved under Asia. Where the rivers come together like this, is the E. end of this plate's north moving edge.

 

[fresh_42]

The Great Lakes are obviously an endpoint. Someone should have told Hypophthalmichthys nobilis.

 

[BWV]

There a longer route than this?

https://river-runner.samlearner.com/?lng=-109.81844548931285&lat=43.69692874331534

 

[fresh_42]

The area between E. India, Myanmar, Chine and Thailand is really interesting.
Four major rivers (Ganges, Irrawaddy, Mekong, and Yangtze), running in parallel, pretty close together.
I think this from slow changes in elevations and flow patterns as the India plant was shoved under Asia. Where the rivers come together like this, is the E. end of this plates north moving edge.

I find Rhine and Rhone funny. Not only that they spell almost equal, but they also have their wellsprings pretty close (only a few kilometers). But one ends up in the North Sea, and the other one in the Mediterranean Sea. And a few kilometers more and you will find the Black Sea as a destination.

 

[anorlunda]

I find Rhine and Rhone funny. Not only that they spell almost equal, but they also have their wellsprings pretty close (only a few kilometers). But one ends up in the North Sea, and the other one in the Mediterranean Sea. And a few kilometers more and you will find the Black Sea as a destination.

It is indeed a fun toy. I did the same with the Erie Canal and the Champlain Canal in New York, because I know the exact locks where the water divides between the Hudson and St Lawrence Rivers are. The tool got them exactly right. As a bonus, the animated Ariel tour following the water down to the sea was fun to watch.

 

[anorlunda]

Another fun test. The Mosquito Lagoon in Florida (4,740 acres (1,920 ha), <1.5 m deep). The River Run tool correctly identifies that somewhere in the middle of that shallow lagoon is a water divide. Some water runs North to Ponce Inlet, and some water runs south to Sebastian Inlet despite the fact that there is no fresh water source for the lagoon. The lack of a water source, I would think makes it a difficult case. Very impressive.

Edit: Here's what makes the Mosquito Lagoon Case difficult. Consider the blue as salt water. The round part is the lagoon. The black arrows show tidal currents. In the ideal case, it seems indeterminate where a raindrop hitting the lagoon will go. But non-ideal differences in the size, shape, depth, and elevations of the paths may determine the fate of the raindrop in real life.

 

[fresh_42]

I think I will add it to my list. It's funny, scientific, and good enough, although it has some problems with the Great Lakes and the Mexican border, but which American hasn't.

 

[Astronuc]

Hudson

A bit of trivia on the Hudson River. It is a tidal estuary up to the first dam and lock (The Troy Federal Lock and Dam) between the towns of Green Island and Troy, NY. The Mohawk River joins the Hudson River in Cohoes, NY, just north of the Troy Dam & Lock. A nice webpage (from Suzanne Spellen of Troy) with some background.

http://www.spellenoftroy.com/blog/where-the-tides-end-in-troy-natch

Henry Ford's Ford Motor Company had a power plant there.

Edit/update - another piece of trivia from Spellen of Troy

The State’s Erie Canal lock system begins with Lock E2 in Waterford. There is no Lock E (for Erie) 1. Technically that’s the Troy Lock, aka Lock 1. The Champlain Canal technically starts in Waterford, above the lock, so the Waterford Lock on the Champlain system is called Champlain Lock 1, as it has been since 1817.

 

[DaveC426913]

:dons Debbie Downer hat:

This seems kind of cool, but does it give us any more information than a watershed map would?

I mean, an watershed map is nothing more than this app but with all possible routes already rendered, right And, while that my seem like lot of data on a single map, it's moot because every line of data is naturally well-behaved and distinct from its neighbours.

Though the flyover is pretty boss.

 

[anorlunda]

A bit of trivia on the Hudson River. It is a tidal estuary up to the first dam and lock (The Troy Federal Lock and Dam) between the towns of Green Island and Troy, NY. The Mohawk River joins the Hudson River in Cohoes, NY, just north of the Troy Dam & Lock. A nice webpage (from Suzanne Spellen of Troy) with some background.

http://www.spellenoftroy.com/blog/where-the-tides-end-in-troy-natch

Very true. I sailed it many times. The currents are strong. It's amazing that there is still 4.5 feet of tide at Troy, 150 miles from the sea. Henry Hudson had good reason to believe that he found the Northwest Passage.

However, the salt water almost never gets further north than Poughkeepsie.

 

[Astronuc]

However, the salt water almost never gets further north than Poughkeepsie.

True. Only during periods of drought, which has happened relatively recently.

In 1985 - https://www.nytimes.com/1985/08/25/nyregion/salt-in-hudson-imperils-poughkeepsie-water.html
Again in 1995, 2002, 2008, https://ny.water.usgs.gov/projects/dialer_plots/salt_front_1992-2012.jpg
https://ny.water.usgs.gov/projects/dialer_plots/saltfront.html
and more recently in 2016,
https://www.ldeo.columbia.edu/edu/k...2017/DITL Salinity Worksheet 2017 TEACHER.pdf
It seems to happen at least 1 in 8 years.

The salt front of the estuary, where the freshwater runoff meets the saline water, can range from the Tappan Zee Bay near Tarrytown/Nyack in the spring to Newburgh Bay in Poughkeepsie/Newburgh in the late summer or during droughts.

https://www.riverkeeper.org/hudson-river/basics/

 

[Baluncore]

This seems kind of cool, but does it give us any more information than a watershed map would?

In the natural world of rivers and lakes, probably not.
The difficulty arises when a surface gradient map used to define a watershed, becomes a transport connection diagram with cross-overs.
If you could find an aquaduct that crossed a river then the flow cross-over might confuse the algorithm.
https://en.wikipedia.org/wiki/Pont_du_Gard
https://en.wikipedia.org/wiki/Pontcysyllte_Aqueduct
https://en.wikipedia.org/wiki/Broad_Street_Bridge_(Rochester,_New_York)

https://en.wikipedia.org/wiki/Navigable_aqueduct
"There were 32 navigable aqueducts on the Erie Canal, constructed 1817–1825 in New York State, United States. "

 

[DaveC426913]

In the natural world of rivers and lakes, probably not.
The difficulty arises when a surface gradient map used to define a watershed, becomes a transport connection diagram with cross-overs.

I suppose. The Intracoastal Waterway (ICW) makes a connection (through locks) between Lake Michigan and the Mississippi River two separate watersheds.

 

[anorlunda]

:dons Debbie Downer hat:

This seems kind of cool, but does it give us any more information than a watershed map would?

Yes, the flyover gives us the path to the sea. A watershed map doesn't.

 

[DaveC426913]

Yes, the flyover gives us the path to the sea. A watershed map doesn't.

Not sure I follow. The flyover is prettier, but if you pick point on a watershed map, you can follow it all the way to the sea along its entire path.

 

[Baluncore]

The flyover is prettier, but if you pick point on a watershed map, you can follow it all the way to the sea along its entire path.

The ability to fly down the gradient and so map the stream flow from any point to a lake, or the sea, requires all the stream positions be known along with nearby surface gradients.

A watershed map shows the boundaries between different catchment areas. It does not need to show any streams, nor the position of the rivers. If the different catchment areas are coloured in differently then it will have lost all local directional stream flow information.

 

[anorlunda]

Not sure I follow. The flyover is prettier, but if you pick point on a watershed map, you can follow it all the way to the sea along its entire path.

No. The watershed map will not show all the brooks and creeks it follows to a major river. Nor can you see all the meanders of the streams and rivers on a watershed map. At least most watershed maps.

 

[Astronuc]

I like to find locations, like hill or mountain ridges where the flow from either side goes to different places. For example there is a ridge in British Columbia (maybe on the border with Alberta) where one side goes down to the Columbia River to the Pacific Ocean, and the other side drains to the Arctic Ocean (Athabasca-Mackenzie Rivers) and Hudson Bay (N. Saskatchewan-Nelson Rivers).

https://upload.wikimedia.org/wikipedia/commons/e/e4/Columbiarivermap.png
https://upload.wikimedia.org/wikipedia/commons/a/a9/Athabasca_Watershed-WCanada.png
http://www.ramp-Alberta.org/river/geography/basin+landscape.aspx
http://www.ramp-Alberta.org/river/geography/mackenzie.aspx

https://saskriverkeeper.ca/where-does-the-north-saskatchewan-river-come-from/
https://en.wikipedia.org/wiki/Saskatchewan_River
https://en.wikipedia.org/wiki/North_Saskatchewan_River
https://en.wikipedia.org/wiki/South_Saskatchewan_River
https://en.wikipedia.org/wiki/Nelson_River

Similar, there is a ridge, I believe in North Carolina, where the drainage goes north or northwest to the Nantahala and Little Tennessee Rivers to the Tennessee River, to the Ohio River, to the Mississippi River and ultimately the Gulf of Mexico. The drainage to the west or southwest (before turning S to SE) eventually goes via the Tullulah, Tugaloo and Savannah Rivers to the Atlantic Ocean. As I recall, the separation is a few thousand feet bwtween the two headwaters.

https://en.wikipedia.org/wiki/Standing_Indian_Mountain
https://www.americanrivers.org/river/little-tennessee-river/ - The Nantahala River, another tributary of the Little Tennessee, is a very popular whitewater paddling destination, and was home to the IFC World Freestyle Kayaking Championships in 2013.

https://en.wikipedia.org/wiki/Little_Tennessee_River

 

[Baluncore]

Watersheds can change catastrophically.

I am interested in the places where a young and enthusiastic stream approaches a major river with the possibility of the minor stream capturing the headwaters of the major river.

Finding rivers that have been captured is also interesting. Parts of those rivers now flow backwards, so tend to be very gentle, with many meanders.

 

[BillTre]

One of the reasons I find watersheds interesting is that evolving aquatic organisms are often restricted to watersheds. It is much easier for them to move to neighboring environments in the same watershed. It is much more difficult for them to spread to other areas not part of the watershed.

One watershed capturing part of another watershed is one way aquatic organisms can spread to other watersheds.
Transport of eggs in vegetation stuck on bird feet is another.