Considering the water in the Wachusett Reservoir, what is the residence time of water in the reservoir? The Wachusett Reservoir holds 2 x 1011 liters. Assume steady state (the level and volume of the Reservoir is constant). Set up your equation in words before performing the calculation. Residence time = volume / (Flows in or Flow out at a steady rate) Volume = 2 x 1011 liters
Flows in (from b, since its stays constant) =0.325 km3 / yr
Residence time= 2 x 1011 liters / 0.325 km3 / yr