The word for this is confluence.
canal, channel, water course, waterway, aqueduct.
waterways
The two main waterways in the midwest are the Mississippi and Missouri Rivers.
self join
The waterways in Amsterdamn are called canals. The three main canals are called Herengracht, Prinsengracht, and Keizersgracht and they form belts around the city, which is called Grachtengordel.
To graft
A canal.
they called it shnuffeh
A Bayou.
a watermone
quien sabe
when two monomer sugars such as glucose join together they are known as a disaccharide
Eutrophication