Ok, understood.
If the leak isn’t in the piping system then it’s in the tank.
Isolate the leak then plan a course of action. Either repair or replace.
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Baffling rainwater catchment tank problem
- Thread starter JThomas
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If the leak isn’t in the piping system then it’s in the tank.
Isolate the leak then plan a course of action. Either repair or replace.
I had a customer once that kept getting highbwater bills and one morning I went to check for a leak and found a water hose ran from the neighbors yard and the neighbor was filling his swimming pool.
I’ve had many customers where the neighbors would use their water when the neighbors knew they would be gone. Wash cars, pressure wash, filling pools, etc.
Kids will also leave water hose on them someone will happen by and turn it off.
So there are many ways people lose water
I’ve had many customers where the neighbors would use their water when the neighbors knew they would be gone. Wash cars, pressure wash, filling pools, etc.
Kids will also leave water hose on them someone will happen by and turn it off.
So there are many ways people lose water
JThomas
Member
Depending on the level of your cistern compared to the house, even with the pump off you may have enough static pressure that any leak might siphon water out of the tank. Also, some appliances like clothes washers use the pressure of the water to keep their solenoid valves closed, so if the water pressure drops low enough they can pop open. [My clothes washer leaked in this manner for months all over the downstairs while the house was closed up for hurricane season!]. I'd suspect that the reason you aren't seeing any leaks is that the water is all going out into your septic system. Get a plastic water meter with a 0.1 gallon per pulse output and monitor your usage, I think you'll be surprised.
The installer of the tank thought a suction line to an unused pump might be siphoning water out of the tank, but it turned out the line was disconnected where it went down inti the tank, so siphoning was impossible. There is still the other suction line that is currently in use. It goes over the tank wall, down to ground level, up a bank, along a very slight incline to the pump house. All above ground and easily inspected. If there was a leak in this line, the pump would lose prime, which it does not. What happens to the siphoned water after it reaches the pump?
During a hard rain, water runs under the shed door, perhaps 15 gallons. The water disappears in less a day, but the muddiness remains for 2-3 more days. Not so the perimeter of the tank, which appears as dry as the surrounding soil. Where is the 2000-4000 gallons
JThomas
Member
Unfortunately, none apply.I had a customer once that kept getting highbwater bills and one morning I went to check for a leak and found a water hose ran from the neighbors yard and the neighbor was filling his swimming pool.
I’ve had many customers where the neighbors would use their water when the neighbors knew they would be gone. Wash cars, pressure wash, filling pools, etc.
Kids will also leave water hose on them someone will happen by and turn it off.
So there are many ways people lose water
JThomas
Member
No irrigation.You may have an irrigation head siphoning the tank with the pump off.
No irrigation.
Turn the pump off AND a valve off at the pump to determine the tank is leaking or not. You need to eliminate the possibilty of siphoning
I’ve posted this before, but you need to isolate the piping from the tank and then determine where your leaks are.
I’d also verify how much water I was receiving and install a water meter on the outlet so you can monitor use. You may be using more than you think
When the totality of your findings don’t make sense ........you’re either interpreting them wrong or you’ve not performed the tests correctly.
When the totality of your findings don’t make sense ........you’re either interpreting them wrong or you’ve not performed the tests correctly.
JThomas
Member
Depending on the level of your cistern compared to the house, even with the pump off you may have enough static pressure that any leak might siphon water out of the tank. Also, some appliances like clothes washers use the pressure of the water to keep their solenoid valves closed, so if the water pressure drops low enough they can pop open. [My clothes washer leaked in this manner for months all over the downstairs while the house was closed up for hurricane season!]. I'd suspect that the reason you aren't seeing any leaks is that the water is all going out into your septic system. Get a plastic water meter with a 0.1 gallon per pulse output and monitor your usage, I think you'll be surprised.
thanks for the reply. The top of the catchment tank is below the pump shed, so siphoning would have to defy the laws of physics, or at least the old "water seeks it's own level".
wpns
Well-Known Member
OK, that's good to know. Are all the other plumbing lines above the level of the top of the catchment? I don't have a good feeling for how your system is laid out, so I'm mostly just guessing, and using my own experiences to guide my guesses.thanks for the reply. The top of the catchment tank is below the pump shed, so siphoning would have to defy the laws of physics, or at least the old "water seeks it's own level".
When you turn the pump off when you are away, and you turn it back on when you return, does it run to ge the pressure back up, or does it hold pressure?
If I was on the jobsite this would have already been “ case closed “ .
The tank has an intermittent leak, the piping, the occupants have used the water.
Now which one is it ? Valves and water meters would determine that for me over a period of time.
It’s as hard as you make it.
The tank has an intermittent leak, the piping, the occupants have used the water.
Now which one is it ? Valves and water meters would determine that for me over a period of time.
It’s as hard as you make it.
JThomas
Member
OK, that's good to know. Are all the other plumbing lines above the level of the top of the catchment? I don't have a good feeling for how your system is laid out, so I'm mostly just guessing, and using my own experiences to guide my guesses.
There are pressure lines going to two different locations--a house that is above the tank and the pump, and a a shed
that is also a dwelling. The latter is below both tank and pump. We turn the pump off when not needed, then turn it on for showers and to do dishes. It runs to build pressure.
When you turn the pump off when you are away, and you turn it back on when you return, does it run to get the pressure back up, or does it hold pressure?
JThomas
Member
{UPDATE]I do have valves that shut off any suction lines that might permit siphoning (if the tank wasn;t lower than the lines and the pump). Seeing as how thewater level stayed at 18 inches, I went ahead and put in 6000 gallons, So far, the level is staying there. Why doesn't it leak out like it did before? I also dug little holes about 14" apart all the way around the perimeter of the tank, figuring moisture from a leak would wet the holes near the leak, We'll see.Thanks for the reply. I don't have an irrigation system yet. Just household usage of maybe 20 gallons per day. No running toilets and no pressure line leaks. no signs of a big (or small) leak anywhere. The soil around the perimeter of the tank is dry, aside from what might be expected from recent rain. 2000 gallons a day is a lot of water to just lose.
JThomas
Member
If I was on the jobsite this would have already been “ case closed “ .
The tank has an intermittent leak, the piping, the occupants have used the water.
Now which one is it ? Valves and water meters would determine that for me over a period of time.
It’s as hard as you make it.
What makes a leak intermittent? One time it leaks down to 6 inches, the next time (fresh water) down to 18 inches, and the next time (fresh water) it is holding steady at 48 inches. What happened to the lower leaks?
JThomas
Member
The tank is below the suction that goes to the pump house (except where it goes into the tank. No irrigation.You may have an irrigation head siphoning the tank with the pump off.
The tank is below the suction that goes to the pump house (except where it goes into the tank. No irrigation.
I don’t think you have a leak. I think someone used the water.
That’s where a water meter in-line would tell the story. You don’t have that......so you get to guess and go through a lot of trouble to determine what’s going on.
Good-luck with it
JThomas
Member
I agree. we now have 6000 gallons in the tank and it's holding steady at that level. what the hell?Sounds like your tank has a leak.
That’s the only other way for water to leave the tank if the pump is not running.
That means you didn’t have a leak. The water was used by someone.I agree. we now have 6000 gallons in the tank and it's holding steady at that level. what the hell?
Install a water meter and next time you have a problem it’ll be easier to figure out.
JThomas
Member
Ok, understood.
If the leak isn’t in the piping system then it’s in the tank.
Isolate the leak then plan a course of action. Either repair or replace.
Right now the level in the tank is holding an inch below the 6,000 gallon mark (added water). If the leak is in the liner, then it took a vacation. The man who installed the tank still thinks it's being siphoned out. I pointed out the fact that the top of the tank is below the pump house and he said he has seen a siphon work uphill. That would mean almost seven feet to the top of the tank, then down to ground level, then up an eight foot bank, then 100 feet along a slightly uphill pipe, then three feet up to the pump, through the pump (pump off in this scenario because we have lost oodles of water with the pump turned off), then it would go out through a pressure line to the house (very slightly uphilL) where it will encounter a leak capable of losing 83 gallons per hour. But why wouldn't the water just stay put-- with no force acting to move it? Besides, if the water was going out of a big pressure line leak (pump on), the pressure would drop at the kitchen sinks, which it does not.
Anyway, I've ordered a water meter (as many have suggested), so that should give a clearer picture. Should be installed in a couple of days.
JThomas
Member
Thanks for the reply. I don't have an irrigation system yet. Just household usage of maybe 20 gallons per day. No running toilets and no pressure line leaks. no signs of a big (or small) leak anywhere. The soil around the perimeter of the tank is dry, aside from what might be expected from recent rain. 2000 gallons a day is a lot of water to just lose.
UPDATE: installed a water meter, as many have suggested. 15 gallons leaving the tank for the day. Probably typical except for laundry days. Water level holding at close to 6,000 gallons. Leaving pump on.
