Any irrigation “experts” in the house?

Help Support CattleToday:

Lisagrantb

Well-known member
Joined
Feb 10, 2020
Messages
185
Reaction score
117
I need some input on options for an irrigation system.

I currently have a 5500 gpm electric driven pump mounted on a barge. The pump is submerged and it pumps up and over a levee that's about 30 feet tall and down the other side and into an irrigation flume. The net elevation change from pump to discharge is about 10-15 feet. I'm having to relocate the entire setup thanks to the state moving a bridge. Since I have to move the entire system I'm looking at ways to improve the setup. One thing I would like to do is get the pump off the barge and onto land so maintenance isn't a problem and fear of the barge sinking. The contour of the ground isn't the best, the pump will need to be about 10-15 feet above water level and I'm not sure if I could ever get it primed. I have another diesel 20" pump at another location that I use an ac compressor to pull vacuum with and get it primed but it's only 5 feet above the water. So I guess my question is what are my options on setting up this system. I'm having to move the pump farther down and the problem is it's not a nice sloping grade to the water, it's about a 10' bluff bank
 

Attachments

  • B4A9A913-5E1A-48B9-AC07-694C41346C12.jpeg
    B4A9A913-5E1A-48B9-AC07-694C41346C12.jpeg
    1.1 MB · Views: 22
  • 37FEF477-2F9C-4063-8FAD-AF97F48AF116.jpeg
    37FEF477-2F9C-4063-8FAD-AF97F48AF116.jpeg
    1 MB · Views: 22
  • 4EA2FAC0-CCF6-455B-B769-3EAD26843363.jpeg
    4EA2FAC0-CCF6-455B-B769-3EAD26843363.jpeg
    1.2 MB · Views: 22
Im not an irrigation person but I have designed and moved a lot of fluids with pumps. Call the mfg or maybe some one who sells pumps and get the specs. They will tell you exactly how that pump should be set up, they can usually calculate all your friction, flow, etc.

I can not see what kind of pump it is in the picture. If you can get a better picture, mfg & serial we can probably look it up online.

My guess is they put it as close to water level as possible for priming and have it floating to maintain that distance as the water level goes up and down. In theory, if you have the pump on solid ground and the level went down far enough in the pond you could lose prime.

There are pumps that won't do that but they likely built it like that for a reason and not just to make you miserable. 😄
 
It's a single stage pump. At this point I'm just looking at this from the 10,000 foot level, what my options are and any ideas. I'm not against a new pump or anything else for that matter just want it dependable and functional.
 

Attachments

  • VTIOM.pdf
    3.3 MB · Views: 11
It's a single stage pump. At this point I'm just looking at this from the 10,000 foot level, what my options are and any ideas. I'm not against a new pump or anything else for that matter just want it dependable and functional.
I understand now. Sorry. Didn't see it was a submerged pump. That makes sense why it's on a barge.

Definitely need a pump company to see your specs and price your options out. That's what I would do.

My guess is that is that style pump is cheaper than other options but I could be wrong.

Hopefully some one else can help.
 
I need some input on options for an irrigation system.

I currently have a 5500 gpm electric driven pump mounted on a barge. The pump is submerged and it pumps up and over a levee that's about 30 feet tall and down the other side and into an irrigation flume. The net elevation change from pump to discharge is about 10-15 feet. I'm having to relocate the entire setup thanks to the state moving a bridge. Since I have to move the entire system I'm looking at ways to improve the setup. One thing I would like to do is get the pump off the barge and onto land so maintenance isn't a problem and fear of the barge sinking. The contour of the ground isn't the best, the pump will need to be about 10-15 feet above water level and I'm not sure if I could ever get it primed. I have another diesel 20" pump at another location that I use an ac compressor to pull vacuum with and get it primed but it's only 5 feet above the water. So I guess my question is what are my options on setting up this system. I'm having to move the pump farther down and the problem is it's not a nice sloping grade to the water, it's about a 10' bluff bank
Dear Lisa,

I don't know if is necessary a barge. We use that with big reservoirs. This pics is a small bridge for suction tube. Is good you install a retention valve with by pass, is easy to prime the pump with the water retained inside the pipeline.
 

Attachments

  • IMG_20220626_131306.jpg
    IMG_20220626_131306.jpg
    558.1 KB · Views: 10
I started thinking about something like that except inverted. I'm sure there is a name for it but what if I installed something like a dry hydrant with a large say 36" pipe and mounted the pump and motor in that. I could use my existing pump and motor and just get a column long enough for the pump to reach the water, in my case about 15'. My current column is 4' now. That wouldn't require priming because the pump will be submerged and it will be on land so no barge.
 
Im not an irrigation person but I have designed and moved a lot of fluids with pumps. Call the mfg or maybe some one who sells pumps and get the specs. They will tell you exactly how that pump should be set up, they can usually calculate all your friction, flow, etc.

I can not see what kind of pump it is in the picture. If you can get a better picture, mfg & serial we can probably look it up online.

My guess is they put it as close to water level as possible for priming and have it floating to maintain that distance as the water level goes up and down. In theory, if you have the pump on solid ground and the level went down far enough in the pond you could lose prime.

There are pumps that won't do that but they likely built it like that for a reason and not just to make you miserable. 😄
Brute, I have a question about my current setup.

The setup I have now I pump up and over a levee that's about 25' from water level to top of levee and back down about 15' for a total net head for the pump of about 10'. There is an air break at the top of the levee to prevent siphoning. The problem is when the pump is running the air break is still sucking air or under a vacuum and this air is carried to the discharge. This is a 12" 5200 gpm@41' head pump and everything stays 12" to the discharge. Total pipe length is about 300' with the high point (the levee) about in the middle. My thoughts are that either the pipeline was designed wrong or the pump is underperforming or maybe some weird venturi effect at the air break.
What are your thoughts.
 
Change your air break. It should be designed to open to allow air flow but a soon as line is full of water it closes.
 
That's the problem, it never gets full. Water never comes out, it's only a vacuum at that point in the line
 
Brute, I have a question about my current setup.

The setup I have now I pump up and over a levee that's about 25' from water level to top of levee and back down about 15' for a total net head for the pump of about 10'. There is an air break at the top of the levee to prevent siphoning. The problem is when the pump is running the air break is still sucking air or under a vacuum and this air is carried to the discharge. This is a 12" 5200 gpm@41' head pump and everything stays 12" to the discharge. Total pipe length is about 300' with the high point (the levee) about in the middle. My thoughts are that either the pipeline was designed wrong or the pump is underperforming or maybe some weird venturi effect at the air break.
What are your thoughts.

So an air brake is not a part we used. We mechanically shut things in and in a lit of cases a vaccum was our friend. Take that in to account with what I type.

Sounds like your air brake valve basicall lets air in to the discharge line to alleviate the vaccum through your pump. It's trying to almost keep the pipeline at atmospheric pressure so the pump does the work going up and gravity and the pump take it down the other side.

When that air brake opens it will also allow water to flow back from the peak, through the pump, in to the reservoir, to some extent.

My solution for that would be a check valve right off the discharge of the pump. That would prevent a back flow to the reservoir and store that water in the line from the peak to the discharge of the pump. If you did that you could put a bypass around it to your suction and basically use it to prime your pump by circulating the water in your discharge.

I think that is what Isia Company is describing, also.

Please get with some one to help design that. I would hate to steer you wrong and cost you a lot of money or even worse, some one get hurt.
 
All it is is a hollow plastic ball inside a cage. When water pushes the ball up it seals the opening when water pressure goes to zero or negative the ball falls down opening the port and allowing air to enter the pipe. Thanks
 
This is how it works but mine just has about a 2" ball as the float
 

Attachments

  • B327950E-3CDC-4BD3-9FB6-9F000B8AA78A.jpeg
    B327950E-3CDC-4BD3-9FB6-9F000B8AA78A.jpeg
    412.1 KB · Views: 4
there will ALWAYS be suction at the top of the loop (unless you restrict your discharge), I don't think that air break is doing any good, manual valve up there for when you want to drain it, check valves at the pump should be enough, it can't siphon since the discharge is higher than the water level in the pond
 
I think you may be correct. One problem I have is there isn't a check valve in the system and that break is the only thing preventing siphon from the discharge to the reservoir. If that's the case then a manual valve would work and I would just open it before stopping the pump. The motor has anti rotation built in so if anything happens while I'm not there the worst that will happen is it will siphon about 50,000 gallons out.
 
I need some input on options for an irrigation system.

I currently have a 5500 gpm electric driven pump mounted on a barge. The pump is submerged and it pumps up and over a levee that's about 30 feet tall and down the other side and into an irrigation flume. The net elevation change from pump to discharge is about 10-15 feet. I'm having to relocate the entire setup thanks to the state moving a bridge. Since I have to move the entire system I'm looking at ways to improve the setup. One thing I would like to do is get the pump off the barge and onto land so maintenance isn't a problem and fear of the barge sinking. The contour of the ground isn't the best, the pump will need to be about 10-15 feet above water level and I'm not sure if I could ever get it primed. I have another diesel 20" pump at another location that I use an ac compressor to pull vacuum with and get it primed but it's only 5 feet above the water. So I guess my question is what are my options on setting up this system. I'm having to move the pump farther down and the problem is it's not a nice sloping grade to the water, it's about a 10' bluff bank
I'm, not an expert, only an electrical engineer. If it were my project and a new bridge was going in and they wanted my barge gone and pump up 15 feet higher....I too would be concerned about priming and maintaining that prime. That said, I would check and see how much rate-flow i really needed....can i get away with 2,000. gallons per minute for a longer duty cycle to make up 5,500 gallon per minute? The reason i'm asking that need for flow rate and duty cycle is my solution would be (get rid of the single large pump and priming nightmare altogether) and put a long steel pipe across the shore and use multiple stainless steel deep well submersible pumps at 300 to 500 gallons/minute. You might find you only need five of them....and if one fails after 6 year....you're only down 1/5th a fraction of water....and they're fairly inexpensive too. A stringer of submersible pumps is what I would do. No barge, no singular fail point pump, no expensive contractors needs...just a low hung metal support pipe for all the submersibles to hang from and hoses/ PVC piping up. That's me...Mr. Cheap, simple, hidden (pumps) and redundant system....keep your money in your bank account, land holdings or in gold/silver.
 
You don't have a problem priming your submersible now correct?

You only need a prime option if you switch pumps to some thing mounted on shore and run a suction line off in the reservoir.

I would add a check valve and a manual valve. If the check is working properly there would be no need to close the manual and no chance of forgetting to open it before starting the pump.

Any time you add valves down stream of a pump consider a high pressure shut off just in case.
 
Correct, not a problem priming. I just thought there should not be a vacuum at the high point with the pump running but as pointed out there is no restriction in the line (valve on the discharge end) that there would be a vacuum unless something created a large enough back pressure to put a little pressure at the high point.

I was thinking that if I could get the entire pipe 100% full then the siphon effect would lower the head pressure and increase pump efficiency. If the pipe isn't full at the top you loose the siphon and it's the same as discharging at the top of the system or in this case the levee. Am I wrong?
 

Latest posts

Top