Here are the answers to practice problem No. 5.1. What is wrong with the calculation of the average daily flow?Answer: I did not consider the drainback each time the pump ran. It is approximately 14 gallons each time so:64 gallons – drainback of 14 gallons = 50 gallons actually delivered to the system.Total flow then becomes: 640 cycles x 50 gallons/cycle = 32,000 gallons deliveredAverage daily flow becomes: 32,000 gallons ÷ 120 days = 267 gallons/day2. Would that change what you think about how this system is operating?Answer: Now the average daily usage is less than the design flow for the system; since
