Want this question answered?
Because it is the land area that supplies water to a river system :)
a drain
The Gulf of Mexico
Lake Michigan
A storm drain will take the water from storms, and bring it to the closest river. This prevents flooding.
Runoff, river system
The Sea of Cortez.
It runs to a creek or river and dumps in there.
A water cycle :]
There are many water forms in Virginia. Some of these include Lake Drummond, the Chesapeake Bay, Toms Cove, the James River, the York River, and the Shenadoah River.
If by water system you mean a river system, then the Amazon River system of South America is the largest.
the hudson river