Many outside iowa hydrants

nicholas bonham-carter

In our cemetery, of 350 acres, there are 40, or 50 iowa hydrants for occasional irrigation. They all seem to have been piped in 1 1/2 galvanized iron pipe, and the pipes are starting to fail.
If we were to do a repipe, what material could we use as an alternative to copper which now has become so expensive?
As you can see from the map, we would not be restricted to a series layout, but could run many parallel lines, maybe with smaller diameter.--NBC

http://www.forestlawnomaha.com/Sections/CompleteCemetery2003.pdf

Jamie Hall

Is it the riser pipe that's failing? Or underground? If it's the risers, I'd use galvanized again. For the underground connectors, polyethylene...

Those Iowas are great gadgets. I have two on the farm here, six foot bury, Been there since... well, at least 50 years now!

nicholas bonham-carter

It's the supply piping. the riser only has water in it when the hydrant is on. I didn't know if pex pipe was approved for underground installations, or not.--NBC

SWEI

PEX or HDPE underground for sure. Rigid risers need isolation from the run pipes or they can wreak havoc when they get hit by a vehicle. We use break-off irrigation risers to offset from the underground run (tee) to the riser.

icesailor

Most irrigation systems in cemetery's use Poly Pipe. Because it is going to a place of unknown quality, you need a RPBF device. If the system has its own well, there are usually no holds barred.

Those "yard Hydrants" usually are leaking in the ground at the bottom of the shaft and you don't know it. The ends are usually rotted off where they connect to the brass bottom connector. If you find some rusted and rotten at the bottom, you are better off replacing them all because the act of trying to reconnect a bad one will usually break it.

Do you leave them on all winter during the cold months or are they shut off? If you drain them, you are better off to run new Poly Pipe lines with just plain risers with Back-Flow protected hose faucets and abandon the old systems. In the Fall, you blow out and drain the systems. No one is going to water their gravesites in January. Turn the system back on in the Spring when it starts to warm up. Don't worry about putting them down below the frost level. Any water left in the pipes can't do any expansion damage because the frost pressure is OUTSIDE and AROUND the outside of the pipe, pushing IN.

I've been to Equine Facilities that use frost free yard hydrants to get water for outside paddocks. If they start leaking in the underground faucet shut-off, water comes out the top, you get a huge free form ice sculpture, and then need a jackhammer to get through 3' of frost to fix the leak. Or shut the system off until Spring.

Not fun.

nicholas bonham-carter

I suppose we would use a 10 foot length of pipe on each side to stabilize them in the ground against accidental impact, or maybe a length of vertical pipe, driven down deeper. We definitely need to go below frost (48 inches)-blowing out several miles of pipe will be no fun!
The alternative may be to have a box in the ground shielding the top of the valve.--NBC

JUGHNE

Iowa or Woodford Hydrants
Nichols, you could check out www.jacobseninc.com , they are in Adair IA . They seem to be a good company that has a "Hydrant block " that anchors yard hydrants and gives a feed thru capability to the next hydrant, though only 3/4" is shown in their catalog. They have 6' buries that are actually about 9' long. Also they have HD PE pipe which has been used in our rural areas for at least 50 years. Personally I would go with the bronze insert fittings. They only show 1" poly pipe in the cat but they have gone the extra mile to get some weird fittings for me. Also you probably only use a few hydrants at a time and might have city pressure of +60 PSI so who knows what 1" might do for you.
Just an option/suggestion. Jugne

JUGHNE

PS: after 50 years it seems maybe time to change the yard hydrants also as backhoe/trenching in a cemetery could be a dicey job to do once, let alone come back to replace a hydrant onesie/twosie. Digger hot line probably won't give you much help with critical locations.

icesailor

nicholas bonham-carter said:

I suppose we would use a 10 foot length of pipe on each side to stabilize them in the ground against accidental impact, or maybe a length of vertical pipe, driven down deeper. We definitely need to go below frost (48 inches)-blowing out several miles of pipe will be no fun!
The alternative may be to have a box in the ground shielding the top of the valve.--NBC

Blowing out several miles of pipe is a walk in the park. It isn't even an issue. Then, remember, If the pipe buried in the ground is full of water, it is the area/soil around the pipe that freezes and applies equal pressure from the outside, in. The water inside can't push out and overcome the resistance of the frost soil. If the pipe is only half full of water, the ice has a place to go. I have never seen an underground irrigation pipe break because there was water in it that was buried in the ground. Maybe a riser at grade or above, That wasn't drained.

Are there any Golf Courses where you are that are irrigated? They have MILES of irrigation pipe buried in the ground. In the Fall, they come by with a wheeled air compressor and blow the whole system out. Where I used to live and work, there were three large golf courses. In the Fall, they just blew the water out with compressed air.

As far as the risers, if you use yard hydrants that stick up, you need to use a post to attach the pipe to. Be sure that the post is below the top. You are better off using flush units that are in a box in the ground.

Ask some company that specializes in golf course irrigation installation and maintenance what they do. Maybe they think that they can't drain it with air. In New England, that's how it is done.