# What Is the Maximum Flow of Water for Different Diameter Pipes?

**The maximum flow of water for a 2-inch steel pipe is 45 gallons per minute, while the maximum flow of water for a 24-inch steel pipe is 18,000 gallons per minute.** The maximum flow of water for an 8-inch steel pipe is 1,600 gallons per minute.

Water traveling through a 2-inch steel pipe moves at a velocity of 4.3 feet per second and features a head loss of 3.9 feet for every 100 feet traveled. Water traveling through a 24-inch steel pipe travels at a velocity of 14.4 feet per second, experiencing a head loss of 2.1 feet for every 100 feet traveled. Water traveling through an 8-inch steel pipe moves at a velocity of 10.3 feet per second and experiences a head loss of 3.8 feet for every 100 feet traveled.

Additional maximum water flow values are: 75 gallons per minute for a 2.5-inch steel pipe, 130 gallons per minute for a 3-inch steel pipe, 260 gallons per minute for a 4-inch steel pipe and 800 gallons per minute for a 6-inch steel pipe. Also, a 10-inch steel pipe has a maximum flow potential of 3,000 gallons per minute, while a 12-inch pipe has a maximum flow potential of 4,700 gallons per minute.