https://waterdata.usgs.gov/ provides a map where you can select local rivers and lakes and see their water level and other data.
Be aware, not all waters are in there - as not all have either sensors or readings or they are simply e.g. privately hold.
How ever - especially for e.g. rivers like the Colorado with it's ever changing water levels due to all the damns and water redirection, this is interesting and helps to see patterns.
With the current very wed winter here on the west-coast it also helps to get an idea of the water levels on some reservoirs and how they changed, this is important as these levels have gone up tremendously for most reservoirs here - what also means a lot of trash suddenly on the water (what was left behind on the shorelines by stupid people) and also a lot of bush and other stuff is now beneath the water line - it might make access to the shoreline easier or harder as well.
Of course, just an example on why this data is interesting.
Hope you find this helpful.
Florian Rossmark
Germany / USA - Carp Angler
