I've wondered about this for years. Looking out at
an irriagated field, I see concrete pipe, about 1-3
feet in diameter sticking up anywhere from 4 to 8
feet. What is it for?

On Jun 24, 10:21*am, Jim Stewart wrote:
I've wondered about this for years. *Looking out at
an irriagated field, I see concrete pipe, about 1-3
feet in diameter sticking up anywhere from 4 to 8
feet. *What is it for?

I am guessing the irrigation water is piped and not in open irrigation
canals and ditches. The pipes serve the same purpose as the vent pipes
in your house: they prevent vacuum locks and allow the water to flow
freely through the pipe. They are called "stand pipes" for obvious
reasons. If there is sufficient volume and pressure at the head end of
the pipe, the stand pipes are not necessary, but where land is flat,
the pressure at the head end is quickly dissapated.

Here in Central Oregon, the irrigation water flows rapidly down hill
and until recently the water was all in open canals and ditches.
Lately, the irrigation companies have been piping the canals to save
water lost to leakage and evaporation. The pressure in the pipes is
enough that some users don't need to pump the water anymore and use
the pressure from the pipe. In other cases, the irrigation companies
have installed electric power generation station to use the excess
pressure to generate and sell electric power.

Hope that is the correct answer to your question. Where are you seeing
the stand pipes? Also, concrete pipes don't rust and rile bullets
don't do much harm.

Paul

In article , wrote:
I've wondered about this for years. Looking out at
an irriagated field, I see concrete pipe, about 1-3
feet in diameter sticking up anywhere from 4 to 8
feet. What is it for?

Ask over in misc.rural -- I'm sure you'll get an answer there.

On Thu, 24 Jun 2010 10:21:08 -0700, Jim Stewart
wrote:

I've wondered about this for years. Looking out at
an irriagated field, I see concrete pipe, about 1-3
feet in diameter sticking up anywhere from 4 to 8
feet. What is it for?

Where I saw those the land is really flat and those are connected to
the higher elevated canals. Really neat watching crop dusters crab
around them.

SW

Jim Stewart wrote:
I've wondered about this for years. Looking out at
an irriagated field, I see concrete pipe, about 1-3
feet in diameter sticking up anywhere from 4 to 8
feet. What is it for?

Pressure relief and vacuum relief. If you suddenly shut off the the
water down stream the water hammer effect
can damage the pipe. The stand pipe is a pressure regulator of sorts.

Bill K7NOM