interbasin

adjective

in·​ter·​ba·​sin ˌin-tər-ˈbā-sᵊn 

variants or less commonly inter-basin

: between, relating to, or involving two or more basins (see basin sense 3)

Interbasin transfers are simple in concept … For example, if the Sabine River basin in East Texas has an abundance of water, it makes sense for a drought-stricken region of the state to purchase water from the Sabine basin.

—Paul Workman

Word History

First Known Use

1872, in the meaning defined above