Home irrigation from well water

[MarcIssan]

So I live in Udon and am planning my irrigation system.  I see the preferred pump is Grundfos MQ 45 so I'll go with that.  My question has to do with filtration.  I've had sprinklers in the USA in each of the last 8+ houses I lived in and every year it seemed I was removing nozzles and scraping sand, bugs, and other stuff from them and that was on city water.  What about here..are you running into plugging issues with the sprinklers or do you have some kind of particle filtration installed.  I plan to irrigate probably 1 rai total since the house, pool and outbuildings take up a bunch of space.

 

Thanks all for your comments. ThaiVisa is my go-to place to learn all kinds of stuff.

[bankruatsteve]

I'm in Udon and the main problem for us is the calcification in just about everything connected to water.  We have an irrigation system using small spray jets that continually need to be replaced/cleaned and re-circulated.  As for pump, depending on how you are irrigating and the source, you can get by with the smallest/cheapest pump.

[MarcIssan]

Thanks bankruatsteve.  That explains why, in an irrigation diagram I saw in a 2009 post, he had the well water for both the house and the garden pass through sediment filters and a softening system before going into two 2000 lt tanks.  I wondered if the hardness affected the irrigation valves and sprinklers and you answered that for me.

 

As for my setup. I'll have some sort of boundary wall around the property.  For the sides, I'm considering concrete posts well set in the ground, maybe even piles driven to the hard pan since my soil is 2-3 meters deep with sandy soil, then attach 10 foot pre-made chain link panels between the posts...then plant climbing and flowering leafy plants that eventually cover the voids with leaves and flowers of various colors.  Or I may plan dense shrubs along it that covers the chain link...I'm not sure.  Either way I need irrigation along the fence.  For the rest of the lawn area, I'll use adjustable rotating sprinklers spaced at 25 feet  more or less.  With the calcification issue, I will likely also run the well water through sediment and softening before it goes into the tanks.  

 

The plot is 50 meters by 75 meters and I'll want irrigation front and back.  Plus I think there is some sort of self filling float system for the salt water pool. And I'll need faucets placed around for hose attachments and for the organic vegetable garden I hope to have.

 

Looking at pump specifications I see the Grundfos MQ 45, for example,  has a volume of 19.9 gpm (75 liters per minute) holding at 65 psi and the Toro Prostream heads put out 3 gpm (11.7 LPM) max with 3/4 " pipe.  So at the high end I can drive 6 heads per station but should likely stick to 4 or 5.  As for the smaller sprayers, I don't have specs for them yet.  I'll need to plot out the layout on CAD.

 

I have read that wear on pumps mostly comes from start/stop so I am trying to figure out how to minimize that on the submersable well pump...the most costly one I'll have.  Maybe you can help there too.  I'm thinking of having 2-3 tanks for irrigation...mostly for storage in the case of a low water table.  (How deep is your well and have you ever run dry?)  Then have 2 more tanks for household use.  They may all be connected or they may not.  If all tanks are filled by the same well pump which pumps at the rate of 85 liters per minute, how can I set up my irrigation system so at the end of the watering cycle, the well pump comes on and runs until the tanks are full again rather than start/stop again and again as the irrigation pump (75 liters per minute) lowers the water table inside the tanks?

 

As you can see I am new to this whole thing having relied on municipal water for all the other irrigation systems I have designed and installed in my own homes.

 

Thanks for any suggestions you can offer.

 

 

 

 

 

 

[VocalNeal]

Your storage tanks will need a float switch(es) to activate the well pump. You throttle the well pump if worried about cycling but I am not aware that the cycling adversely effects pumps. Mitsubishi water pumps cut in and out all the time and the pump/motor outlasts the head tank.  The submersible pump should have a capacitor in the system somewhere to "soften" the start.

 

Level switches are usually one float on an integral electrical cable.  There are units with two floats one high, one low. Or single switches both with NO and NC contacts they just need to be wired up to suit.

 

Either like this

 

 

Or like this

 

 

In the latter case you simply adjust the string. Take either picture to the store and they will know.

 

Any decent shop like Thai Watsadu will have any number to chose from. Set the low one really low and then the tank will take longer to make up the difference between the two pumps.  Throttling both pumps with a ball valve will allow you to balance the system to your liking. 

[MarcIssan]

OK great.  I didn't know how the float switches worked.

 

Marc

 

[bankruatsteve]

You may want to try and test the sprinklers you plan to use at the pressures you mention.  All of the sprinklers I have bought in Thailand blow apart using most pumps.  Our irrigation pump (rated 200W but think that's power consumption vs. head) was the smallest I could find at Home Hub (B1200).  It pulls from a tank and runs continuously (best) when 3 lines are opened - each line has 25 or so small jet sprays (actually closer to a mist).  Each jet will put out a little under 1/2 liter/minute.  That's on 3/4" hose.

[MarcIssan]

Thanks for the heads up.  I haven't shopped for this yet, I'm still reading what others say about different brands.  And really I am 1 year away from moving in and more before I start landscaping.  I have used Rain Bird and Toro back home and at pressure of 60-80 lbs, they worked fine.  But again, I think the Thai shops might lean more toward cheaper brands...not sure.

 

I'll probably use 2 timers...1 each for front and back.  I usually irrigate at night or early AM and make sure only one line runs at a time.  I do 10 minutes shots every day rather than a huge soak 2 times a week or such.   I would think it best to size the station to closely match the pump and include as many heads as it takes to almost use the total volume pumped.

 

So did you install your system or have it done?  I plan to do everything myself except dig the trenches!

[simoh1490]

I have a well that is 15 metres deep and I use it solely to irrigate my garden through a series of sprinkler 13 heads spread across almost one rai using 1 inch PVC pipe, reduced to 0.5 inch at the outlets. The two biggest problems are 1) the amount of rust or in in the water which stains the walls and causes the sprinkler heads to sieze up, and 2) I run a 1 hp centrifugal pump which will only pull to about 9 or 10 metres, since I compete with local farmers for the water table I often have to water first thing in the morning when the farmers pumps have run out of overnight fuel by which time the water table has rebalanced. From 10 to 18 metres a jet pump is needed, beyond that a submersible pump is required.

 

If you have rust in your water (which is typical under 40 feet) and you intend to use a holding tank, you could filter out the rust with a stone cascade before the water goes in the tank, a bit ugly but effective. Otherwise, if your bore is say 15 metres, place your pick up tube/foot valve at 14 metres, that way you'll avoid the debris.

 

EDIT TO ADD: I just bought a Samson 1 hp pump from Global House, about 4.5k, very reliable.

[bankruatsteve]

7 minutes ago, MarcIssan said:

So did you install your system or have it done?  I plan to do everything myself except dig the trenches!

Me and the wife did it.  Not too hard since everything above ground (tree farm).  We used a product sold by Home Hub (forget the company name and can't find it now) that uses a 3/4" hose that appears robust and a plethora of sprinklers and fittings.  The only difficult part was unraveling the hose role without getting crimps.  Most of the sprinklers work by drilling a small hole and then screwing or push to fit.  200m of hose for B1100 (to wit) and the spray jets were cheap.  Hose connectors and other fittings varied in price but not expensive.

[MarcIssan]

One well that is about 8-10 meters lower elevation is at 45-50 meters I'm told.  He sells filtered water but I don't know how often he services his filtration system.  I'm told by someone in the area that wells run 60-100 meters nearby.  I am planning on a submersible pump anyway and there aren't any irrigating farmers nearby so there isn't much immediate competition for the water.

 

The irrigation systems I have installed used all PVC glued and dug in.  I've done one with the ABS pipe but I didn't like working with it.  It's easier if you have long runs to make but I'll have runs between heads of 10-25 meters,

 

As for the discoloration of everything water touches...that concerns me.  You know...new house, fresh boundary walls and driveway...I kind of want it to stay that way.

 

I think softening and filtering the water before filling the storage tanks is the way I'll go and draw from the same set of tanks whether for irrigation or showing.

 

Thanks for the comments.

[VocalNeal]

1 hour ago, MarcIssan said:

You know...new house, fresh boundary walls and driveway...I kind of want it to stay that way.

From my experience everything in Thailand 10 years old looks 20 years old. That or lots of work!

[kamalabob2]

Rain Bird quality drip sprinklers, pop up lawn sprinklers are in fact sold in Thailand. I bought these genuine Rain Bird garden and lawn watering sets in Buriram. They seem more robust and have less issues than a different brand I had bought in Thailand. The quality is on par with Netafim.

[canopy]

I was warned by a well driller the thing that kills submersible pumps are the voltage drops. During high demand periods of the day like early morning and evening the voltage delivered to your house can fall below 220 volts. It's a common phenomenon of Thailand. Couple that with the voltage drop on the cable going way down the well which may have been incorrectly sized to begin with and the pump is running on voltage way under its specifications.

 

If you want to prevent a pump from over cycling, a pressure tank can often be fitted. Grundfos for instance has many and their support will discuss your requirements and make a recommendation.

 

So for pump reliability: buy a good brand like a Franklin submersible, use a pressure tank to prevent short cycling, and understand and allow for the voltage drop to your house and the voltage drop to your pump.

 

[kannot]

On 4/1/2018 at 7:42 AM, canopy said:

I was warned by a well driller the thing that kills submersible pumps are the voltage drops. During high demand periods of the day like early morning and evening the voltage delivered to your house can fall below 220 volts. It's a common phenomenon of Thailand. Couple that with the voltage drop on the cable going way down the well which may have been incorrectly sized to begin with and the pump is running on voltage way under its specifications.

 

If you want to prevent a pump from over cycling, a pressure tank can often be fitted. Grundfos for instance has many and their support will discuss your requirements and make a recommendation.

 

So for pump reliability: buy a good brand like a Franklin submersible, use a pressure tank to prevent short cycling, and understand and allow for the voltage drop to your house and the voltage drop to your pump.

 

Grundfos  Tank 300 litres ,Franklin controller and Super  Hurricane  pump 1 HP uses  a Franklin motor all on 10mm copper  supply NYY cable  running 100metres  1  metre underground in HDPE piping to  2.5mm 4  core cable down the well shaft . Water tested in Bangkok has no iron and very clear. "  wells  one 80m deep the other 50m deep. Installed by myself as "cant trust anyone in Thailand syndrome"

Well water runs 100metres to main house thru 40mm hdpe, both pipes ( water electric) can be seen in the photo

Dead employee for scale.

Pressure switch ( Grundfos) and stainless manifold .

Got an identical second system from a  second well but using a smaller Grundfos  tank.

And  finally I have a  electric 1.5hp pump down by my lake  which can connect to the entire system for  irrigation which I  built recently  as well as  the   village   supply which has a  stainless mesh filter on to screen out the shells  snails dogs etc that seem to come down the pipeline.

Learnt years ago to  rely on myself here as  everything else is..................

[kannot]

On 5/17/2017 at 12:30 PM, MarcIssan said:

Thanks bankruatsteve.  That explains why, in an irrigation diagram I saw in a 2009 post, he had the well water for both the house and the garden pass through sediment filters and a softening system before going into two 2000 lt tanks.  I wondered if the hardness affected the irrigation valves and sprinklers and you answered that for me.

 

As for my setup. I'll have some sort of boundary wall around the property.  For the sides, I'm considering concrete posts well set in the ground, maybe even piles driven to the hard pan since my soil is 2-3 meters deep with sandy soil, then attach 10 foot pre-made chain link panels between the posts...then plant climbing and flowering leafy plants that eventually cover the voids with leaves and flowers of various colors.  Or I may plan dense shrubs along it that covers the chain link...I'm not sure.  Either way I need irrigation along the fence.  For the rest of the lawn area, I'll use adjustable rotating sprinklers spaced at 25 feet  more or less.  With the calcification issue, I will likely also run the well water through sediment and softening before it goes into the tanks.  

 

The plot is 50 meters by 75 meters and I'll want irrigation front and back.  Plus I think there is some sort of self filling float system for the salt water pool. And I'll need faucets placed around for hose attachments and for the organic vegetable garden I hope to have.

 

Looking at pump specifications I see the Grundfos MQ 45, for example,  has a volume of 19.9 gpm (75 liters per minute) holding at 65 psi and the Toro Prostream heads put out 3 gpm (11.7 LPM) max with 3/4 " pipe.  So at the high end I can drive 6 heads per station but should likely stick to 4 or 5.  As for the smaller sprayers, I don't have specs for them yet.  I'll need to plot out the layout on CAD.

 

I have read that wear on pumps mostly comes from start/stop so I am trying to figure out how to minimize that on the submersable well pump...the most costly one I'll have.  Maybe you can help there too.  I'm thinking of having 2-3 tanks for irrigation...mostly for storage in the case of a low water table.  (How deep is your well and have you ever run dry?)  Then have 2 more tanks for household use.  They may all be connected or they may not.  If all tanks are filled by the same well pump which pumps at the rate of 85 liters per minute, how can I set up my irrigation system so at the end of the watering cycle, the well pump comes on and runs until the tanks are full again rather than start/stop again and again as the irrigation pump (75 liters per minute) lowers the water table inside the tanks?

 

As you can see I am new to this whole thing having relied on municipal water for all the other irrigation systems I have designed and installed in my own homes.

 

Thanks for any suggestions you can offer.

 

 

 

 

 

 

soft water no good  for the plants  irrigation