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Name: Dan B.
Status: Educator
Age: 30s
Location: N/A
Country: N/A
Date: June 2004

What are the advantages of increasing the diameter of 3/4" diameter water pipe to 1" diameter water pipe? Typically, the main water supply comes in on a 3/4" diameter pipe. Plumbers seem to tee off the 3/4" diameter pipe and increase the size of the pipe to 1" diameter for irrigation systems. What is the reasoning behind this? Does the volume, pressure, and or flow rate change to benefit irrigation systems?

This sounds like a plumbing and building code problem. A large pipe will flow more water than a smaller. I assume that builders and water supply people have decided that 3/4" is adequate for most uses. For irrigation, which involves long distances, it is wise to go up to 1" to minimize any further loss in flow. Of couse, 1" throughout would be better than a mix of 3/4" and 1".

Bob Erck

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