1 million gallons per day is equivalent to how many cubic feet per second?

• A. 0.5 cfs
• B. 1.0 cfs
• C. 1.55 cfs
• D. 2.0 cfs

Answer: (C)

To convert 1 million gallons per day (MGD) to cubic feet per second (cfs), we can use the conversion factors for gallons and time.

1 million gallons is equivalent to 1,000,000 gallons. To convert gallons to cubic feet, we know that 1 cubic foot equals approximately 7.48 gallons. Therefore, the conversion of 1 million gallons to cubic feet can be calculated as follows:

1,000,000 gallons ÷ 7.48 gallons/cubic foot ≈ 133,681.41 cubic feet.

Next, since we are converting a daily flow rate into a per second flow rate, we need to convert days to seconds. There are 86,400 seconds in a day (24 hours × 60 minutes × 60 seconds).

Thus, to find the flow rate in cubic feet per second:

133,681.41 cubic feet ÷ 86,400 seconds/day ≈ 1.55 cfs.

This calculation reveals that 1 million gallons per day is equivalent to approximately 1.55 cubic feet per second. Therefore, the correct answer is that 1 million gallons per day is approximately equal to 1.55 cfs.