Water is life, they say. Without it all things parish. This is also true of deer. But how much water deer require on a daily basis to sustain life depends on weather conditions and other factors. The most common consensus is the amount also varies seasonally. During the spring when forage is lush and plentiful deer require less water, taking it in from what they eat. During summer when air temperatures heat up and foliage lushness is dissipating the need for daily water intake often increase, especially during periods of drought. The same is often true during the fall and hunting season.
Although I have no scientific data to substantiate it, my personal belief is that deer are naturally drawn to water and will have at least one reliable water source within their home range. It might be a lake, a farm pond, a river, creek or small seepage or spring. It might not be used daily, but deer know it is there and will use it as needed. It is also my personal belief deer, especially mature bucks, like to bed close to water, particularly during warm weather