Grizzly bears use water to drink like any mammal or life form would. They also eat water in the food they eat like fish which they catch in water, because fish can't live without water. Grizzlies tend to stay by water, because that is where most of there other food is too. The other food may be berry plants that need water to grow and nuts that grow on trees that need water to survive.
Grizzlies use water to stay clean too. They use the water they hunt in also to keep them clean. If the water has a strong current they just stand a they clean that way and if the water is still they swim around to clean. They sometimes may lick themselves, to keep clean, if a large enough body of water is not around.
Grizzlies also play in the water. They play-fight, splash each other, and swim around in the water. They may also just mess around in the water. This is how Grizzlies use water.