The average annual rainfall in an area is 60 cm The average

The average annual rainfall in an area is 60 cm. The average annual evapotranspiration is 35 cm. Thirty percent of the rainfall infiltrates and percolates into the underlying aquifer, the remainder is runoff that moves along or near the ground surface. The underlying aquifer is connected to a stream. Assuming there are no other inputs or outputs of water to the underlying aquifer and the aquifer is at steady state (neither gains nor loses water), what is the amount of baseflow contributed to the stream from the groundwater?

Solution

Water whic is perculated into acquifer will contribute to stream as base flow in the form of groundwater.

So given annaual rainfall = 60 cm

30% of rainfall infiltrates into aquifer so ground water accumulated in aquifer = .30*60=18cm

So ground water contributed to stream is 18cm