Irrigating uphill?

[throwaway]

In the spirit of tapping into the impressive knowledge base here, and asking another long tail question that isn't easily answered by google or TV search, here is my inquiry of the week. Can I semi-automate irrigation of the garden?

My property is a hill, and there is about a 10 foot steep vertical climb from the hose bibb to the garden area. Although I haven't been able to find town code for backflow prevention, it seems that anytime the emitters are above the supply, you run the risk of backflow if water pressure were to drop. Google-fu says the only reliable way to prevent black flow on grades is a $300+ RPZ style that would need a plumber to install

For now the plan is to mulch and hand water as needed. I thought about putting a rain barrel at the top of the hill, but there wouldn't be enough pressure for a normal drip system (and I prefer not to run mosquito hotel). Or I could set up a top off system for a tank in the basement, run some PVC from a pump on a timer with a really good head through the wall and up into the garden area. Maybe that's a solution in search of a problem though. Are there other options? There has got to be a better way.

[FourOaks]

I believe you need a vacuum breaker as well as a simple back flow preventer. When the water shuts off, any remaining water in the line should gurgle out at the vacuum breaker.

[Worth1]

Do you intend to just use a water hose for this?
If so just use what is called hose bib vacuum breaker at the faucet and you are good as gold.
There is no need for a fancy reduced pressure assembly or back flow preventer that costs hundreds of dollars.

Any time you use underground piping it gets a little more complicated but even then you dont need the fancy stuff if you know what to buy.
So lets forget the barrels and so on and just talk about pipe and hoses so I can help you.

I know just about anything you need to know about what is called water cross connections.
Worth

[Worth1]

I am going to go ahead and discuss the types you can use and where.

A reduced pressure assembly is for any system that my have other contaminates injected into it like fertilizer or chemicals.
If the pressure on the head end is lower than the down stream end it dumps out a valve in the middle.
These are the ones you see on street corners sometimes that are huge.
I use this type at home.
The draw back is they have to be above grade with the dumb opening 12 inches above the soil.
The back flow preventer is more like a double check valve but it isn't the same thing.
They can be underground

Both of the above have test ports.
Then you have a slew of different types of vacuum breakers.
Some you can test some you cant.

Then there are automatic anti siphon valves.
If you use these you dont need any of the above.
The drawback is they have to be 18 inches higher than the highest water emitter.

What you DONT want to do is put any one of these down stream of a reduced pressure assembly.
For one there is no need to.

Worth

[throwaway]

Worth,

Intention was to run a hose above ground from a splitter on the bibb (https://www.plumbingsupply.com/image...th-shutoff.jpg) to the drip system and bury the drip line/emitters under the mulch.

So the vacuum breaker valves should still trip if say, a hydrant is opened nearby and my municipal pressure drops?

[Worth1]

Originally Posted by throwaway

Worth,

Intention was to run a hose above ground from a splitter on the bibb (https://www.plumbingsupply.com/image...th-shutoff.jpg) to the drip system and bury the drip line/emitters under the mulch.

So the vacuum breaker valves should still trip if say, a hydrant is opened nearby and my municipal pressure drops?

Any time the supply pressure is lower than the down stream pressure the water from your hose lows out the vacuum breaker.
One thing you could do if you were inclined to do so would be to put the vacuum breaker at the end of the hose at the top of the hill on a pole or something.
But I see no reason.
The breaker doesn't (trip) like an electrical breaker.
The most it will have to do is overcome that 4.33 psi you uphill head pressure is at 10 feet.

[BigVanVader]

They also make subsurface dripline now that is pressure compensating. My garden is on a downhill slope and this stuff http://www.rainbird.com/LANDSCAPE/pr...ipline/XFS.htm can be buried, never gets clogged and has built in pressure compensating (idk if that is the proper terminology) but in short it keeps the bottom of my garden from getting waterlogged.

[Worth1]

Originally Posted by BigVanVader

They also make subsurface dripline now that is pressure compensating. My garden is on a downhill slope and this stuff http://www.rainbird.com/LANDSCAPE/pr...ipline/XFS.htm can be buried, never gets clogged and has built in pressure compensating (idk if that is the proper terminology) but in short it keeps the bottom of my garden from getting waterlogged.

The city of San Marcos Texas now requires that you use this stuff if your yard is on a certain slope.
Instead of above ground sprinklers.
This is to keep water from running off down hill.

If you use this stuff you better use a darn good filter before it as you would any drip system of it will get clogged up.
Mine is on a 200 mesh filter.

[throwaway]

Worth,

Does that mechanism ever foul? Would you/could you clean out the AVB every so often?

[Worth1]

Originally Posted by throwaway

Worth,

Does that mechanism ever foul? Would you/could you clean out the AVB every so often?

I have no idea if it does or not but if it does it will fail on the safe side i would think.
I had one on a hose bib for years and it never failed.
It did drive me nuts because if I wanted to turned the water down on the hose so I got a trickle it leaked out the vent holes due to no back presser.

Even though I am a huge proponent of back flow prevention I find some of it to be over the top.
But they have to account for every idiot and thing out there.

Lets say you are filling up a barrel of fertilizer and it takes awhile.
You stick the end of the hose in the barrel and walk away.
The water main breaks at this same time.
Now your barrel of water is being sucked into the main water supply, maybe.
To keep this from happening just use the air gap method like your sinks are.

[kurt]

The P trap stops any back flow for simple gravity systems.Can be used as a vessel to carry enough water to prime a non self priming pump for well water.Its clever use as the water seal for the methane gas from non sanitary (crap/urine pipes,emitting to th e sky's via vent stack to roof) have long been used.A cistern(think water tower cityscape)could bee used in con★★★★★★★★ with minimal city pressure on a simple water timer.Just throwing this out with the brief existing conditions you supplied.Good Luck.

[Cole_Robbie]

I would think that you would want the header line at the top of the hill.

If you have a tank of standing water, mosquito dunks are good for plants anyway, kills nematodes and larvae.

The pump you would want is a shallow well jet pump. They are about $180. They typically need a dedicated 15 amp circuit.

[throwaway]

So I'm trying to think through your posts. Kurt, your idea is a tank at the top of the hill, municipal water pressure to push water to the tank, pressure from the supply pushes water through the irrigation system, and a p-trap somewhere along the line from the water supply to break any backflow? Cole's, your idea is water tank at the top of the hill, pump sits in the tank or the house to fill the tank and provide pressure?

[kurt]

All solutions will require some mock type experiment,grab some materials,inexpensive aquarium pump,old hoses,igloo cooler,there are some diagrams from earlier post(will find).adjust size flow to your regimin,now be adjustable after initial tests.Here in my hood it costs 400 bucks for 30 ft deep irrigation,another 50 for forty plus foot drinking water well.

[Cole_Robbie]

The tank would only be for a low-pressure system. You should have plenty of municipal pressure out of the hose, enough to skip the tank if you want. I use drip tape, which requires a pressure reducer, to 10-12 psi. Out of the hydrant, my city water is usually 30-40 psi.