How many million gallons are equivalent to 318 acre-feet?

To determine how many million gallons are equivalent to 318 acre-feet, it's essential to understand the conversion factor between acre-feet and gallons. One acre-foot is defined as the volume of water required to cover one acre of land to a depth of one foot, and it is equivalent to 325,851 gallons.

To convert acre-feet to gallons, you multiply the number of acre-feet by the number of gallons per acre-foot:

318 acre-feet × 325,851 gallons/acre-foot = 103,984,707 gallons.

Now, since the question asks for the equivalent in million gallons, we divide the total gallons by 1,000,000:

103,984,707 gallons ÷ 1,000,000 = approximately 104 million gallons.

Thus, the correct answer reflects this conversion. This understanding of volume conversion is crucial for anyone working in water resource management, as it helps to accurately assess and convey water quantities in different measurement units, which is often necessary in reports, analyses, and daily operational planning within water treatment and distribution systems.