Water and salt drives are linked because both systems maintain blood osmolality and sodium concentration.

“The Thirst for water and the desire for salt are much more tightly linked because um the purpose of both systems is to maintain the composition of the blood At Its Right concentration so you you want to have the right osmolality the blood which you can just think of in simple terms as sort of the the total concentration of all the salts um uh it's a little more complicated than that but it doesn't really matter and uh uh uh you also specifically need to maintain the sodium concentration at the right level”