Looking for irrigation leak?

Question

I am the superintendent at a golf course and I have an irrigation leak at 180 gal. per min. I know it is in a swamp that is filled with cattails, so it is hard to walk through it, I was wondering if anyone has any ideas on how to locate it. I dumped 11 gal. of dishsoap into the system, but never saw bubbles. I am looking into Fluorescein dye to dump into the system, to see it in the water of the swamp, if anyone knows if that is a good idea or knows where to buy it, how much it costs or how much I would need let me know.

Answer 1

They sell the chemical that makes water look blue at places like tractor supply for about US$38 per gallon. It only takes about a quart to turn an entire large pond blue. If you dump it into you system you need to be watcing the swamp as it comes through as it will disperse rapidly through the water.

Pet Smart sells it too.

http://www.ponddye.com/ $49

Answer 2

180 gallons per minute?  A leak of that size should look like Old Faithful.  Find and fix it and your swamp will probably be gone.

Is the line actually buried in the swamp?  If so, finding it is one thing, fixing it is something totally different.  How are you going to dig it up and when you do, how are you going to fix a pipe that's at the bottom of a water filled hole?  Pipe of any sort doesn't stretch well and to get the line above the water, you'll have to dig up a tremendous amount of line.  Even if you do get it up and repaired, if there's much air in the line, it'll float.    

Is there any way to trench in new line around the quagmire?  Even if it is quite a bit further, the cost involved with sloshing through water and muck and possibaly dewatering the hole is going to be very, very expensive.  If relocation is at all feasible, why spend a bunch of time and money finding the leak only to find it's financially impractical to repair?  If you really must repair the old line, compression fittings can be used on PVC and PE pipe even while underwater.  If metal pipe, try a saddle clamp.

Answer 3

rebury it around the swamp

how would you fix it in the swamp anyway?

Answer 4

Given that it is a golf course I'm sure you have the available capital to replace what is obviously an aging section of line. Polyethylene pipe is less expensive than the time/ labor and chemicals that you will need to find and repair the leak, which seems rather large. Those losses must affect the downstream pressure of your irrigation heads so you will eventually incur other costs, especially as the season heats up. Also keep in mind that your assumption of where an unknown leak is though logical, is still an assumption. If you shut that particular branch down for a short time and find that your water meter no longer registers your loss, then you narrow it down and the probability goes up. If you can then shut down that branch after the swamp in question and the meter indicates a huge drain, you can assume the break is in the area between the two shut off points, but that is all you can assume. One thing my Professor (engineering) was always very fond of repeating was that if you are (working) on something and find that after the work is done that there is a problem (something broke), you should immediately go back over what you have done as the cause will invariably be there. So, given a schematic of the irrigation system, go back and look at any work done anywhere near the line in question. Even the most innocent item needs to be considered. A heavy backhoe ripping out a stump (as an example) might compact the soil over a line, pushing the line into a large, sharp rock and weakening it or breaking it. Could have happened a week before the problem was noticed. It may not be where you think and a sink hole may be forming as the flow goes to groundwater. That may or may not eventually show in the swamp. Your soap may take a week or month and suddenly turn up but the size of the loss indicates it will probably be too diluted to see, and that would also be the case with dyes; it will be too dilute and take longer to appear than you expect if at all.

Solution: Unless you are absolutely sure of the swamp you need to install if you have not already, isolation valves before the swamp and after the swamp. If you shut the line off before the swamp and have no loss on the meter, then it is after. If you then shut off the line after the swamp and you have a loss that large, then you know you are right. Replace the whole line and put it in a location that allows you to service it. The cost for polypropylene is nothing compared to messing around with the foolish thing. If it breaks and age is a consideration, replace it instead of fixing it as it will go again and Murphy's Law and it's corollaries regarding golf course irrigation state implicitly that the line will break at the worst possible time in the most inaccessible spot, and will cause you to get sued by a customer, and/ or environmentalists, and/ or the state and federal government. Then you get fired and caddy until you retire, a broken and angry groundskeeper.

Answer 5

IN MISSISSIPPI--CAT TAILS GROW IN WATER--SO I WOULD HOOK UP AN AIR COMPRESSOR TO THE SYSTEM---APROX 30 LBS OF AIR PRESSURE  .  EQUAL S  100 LBS OF WATER PRESSURE--SCHEDULE 40  PVC PIPE IS TESTED  AT 200 LBS PSI --- SO IF YOU PUT 60 LBS OF AIR INTO THE SYSTEM IT WOULD STILL BE SAFE-- IF THE LEAK IS IN THE POND --YOU OUGHT TO SEE A LOT OF    BUBBLES COMING FROM THE AREA--  ALL THE DYE YOU PUT IN THE SYSTEM IS GONNA TELL YOU THE LEAK IS IN THE POND-- BUT NOT WHERE THE LEAK IS--  AIR   BUBBLES WILL LET YOU KNOW ABOUT WHERE IT IS--DEPENDING ON HOW  MANY  SPRINKLER HEADS  IS ON  THIS LINE --YOU MAY HAVE TO CAP THEM  ALL OFF--THIS WAY THE AIR HAS ONLY ONE PLACE TO  COME OUT--AND THAT WILL BE WHERE THE LEAK IS---HOPE THIS HELPS