Have a weird Septic issue

[PILOON]

My field is about 20 ft higher than my tank.
One piece of advice I followed was to install a back flow valve in the pump outlet line but also to drill a small (like 12") hole in that valve. The reasoning being that the down rush of the pipe full of liquid could actually damage the pump motor.
Also due to the rocky terrain it was almost impossible to bury the pump line below the 4" frost depth and the leak hole in the valve insured that the line was normally dry.
This has worked just fine for over 24 years.

My main concerns are our frequent power outages that could prevent pump from maintaining safe levels in my septic tank. Once during a prolonged outage the pump float switch got tangled and the pump just kept running non stop, (now since rectified).
I also installed a second float switch that warns of an overfilled (failed pump) situation.

LOL worst pump fails always seem to occur in the coldest days of winter. We once needed to build a fire over the access in order to thaw the lid free.

 

[plowhog]

You can find the exact difference using a garden hose. Run a garden hose from the manhole to the septic tank. Start slowly filling it with water on the high end (gravity fed.) Water will be coming out of the lower end. Raise up the lower end until the water no longer comes out nor goes back in. That's the height of the other end.

 

[lzicc]

Piloon, I hate these issue's, but at least it is warm out. This could have happened in the dead of winter. There is an inline backflow valve in the system.

plowhow, I would need to get a good 300' of hose to do that if I am understanding you correctly. If I do that, how do i find out the difference, would i measure the length of the hole that I lifted up?

 

[lzicc]

I have a rotary laser level with a grading stick. I should be able to use that to find the elevation difference, it will just take some time.

 

[wagne223]

To confirm, the city sewage is uphill from the tank maybe about 20'. This is common around here since the city sewage happens to be available at a higher elevation. The leach field was elevated also. It hasn't rained for about week now. I've been checking the tank and it is filling up again. I can hear the pump running, but I am wondering if the pipe that goes to the city sewage may be either blocked or broke. The pump ran all night and the tank level did not go down. BTW, I did replace the pump with a new one when this all started. I am going to try to snake the 1 1/2" line to see how far I can get. What would be a good way to find out the exact elevation different of the septic tank and the city sewage manhole? I'm guessing at 20'. I would like to get a better idea. I found an Iphone app, but it was flaky.

You are on the right track. There is a restriction somewhere.
A 1/2 HP grinder pump at 20 feet of head, will pump around 1300 gallons per hour or about 21 gallons per minute. There is no way your pump should be running continuously.

There will be at least one check valve in that line.
You cannot simply snake the line.

Check valves can stick or become clogged.


If you are not sure what you have, you will need to start digging.
If your not up for it call a plumber.

You are going to burn up your pump if it continues to run against that much resistance plus all the electricity your wasting.

 

[Tractor Seabee]

You can find the exact difference using a garden hose. Run a garden hose from the manhole to the septic tank. Start slowly filling it with water on the high end (gravity fed.) Water will be coming out of the lower end. Raise up the lower end until the water no longer comes out nor goes back in. That's the height of the other end.

He may need a pretty high ladder. A theodolite and the math tables and it can be calculated the way a surveyor would do it. Today it is all electronic and computerized. In the long run; guessing is probably good enough. The elevation difference is not his basic problem anyway. Basics; he needs to know how his line feeds into the utility manhole. If a check valve is stuck open he may be draining other sewage back into his tank. I have seen stranger things in my lifetime.

Ron

 

[Tractor Seabee]

You are on the right track. There is a restriction somewhere.
A 1/2 HP grinder pump at 20 feet of head, will pump around 1300 gallons per hour or about 21 gallons per minute. There is no way your pump should be running continuously.

There will be at least one check valve in that line and possibly a backflow preventerr.
You cannot simply snake the line.

Check valves and backflow preventer can stick or become clogged.

In commercial applications, a backflow preventer must be inspected and tested every year.

Not sure about residential.

If you are not sure what you have, you will need to start digging.
If your not up for it call a plumber.

You are going to burn up your pump if it continues to run against that much resistance plus all the electricity your wasting.

New one on me; never seen a BFP in a sewer line. That's what a check valve does. But stranger things have happened.

Ron

 

[lzicc]

There is a back flow inline on the vertical part of the pipe where it comes up from the pipe. I disconnected after the back flow and water was coming out really good, so I think that is ok. There has to be a clog between the manhole and where the pipe leaves the septic tank. Or the pipe is crushed which i find hard to believe. It looks like schedule 40 pipe and of what I can tell, it's buried about 3' down. Once the rain subsides, I am going to measure the distance so I have a better number of how far the manhole is from the septic and also check elevation. This way I have some real numbers to go by. I am going to get a 100' 3/8" snake and try to push it through the 1 1/2" pipe. There should be no resistance unless there is a blockage. Of what I can tell, there should only be 1 elbow close to the tank that I have to snake past. Other than that, it should be a straight line to the manhole.

You are on the right track. There is a restriction somewhere.
A 1/2 HP grinder pump at 20 feet of head, will pump around 1300 gallons per hour or about 21 gallons per minute. There is no way your pump should be running continuously.

There will be at least one check valve in that line and possibly a backflow preventer.
You cannot simply snake the line.

Check valves and backflow preventer can stick or become clogged.

In commercial applications, a backflow preventer must be inspected and tested every year.

Not sure about residential.

If you are not sure what you have, you will need to start digging.
If your not up for it call a plumber.

You are going to burn up your pump if it continues to run against that much resistance plus all the electricity your wasting.

 

[lzicc]

When I pulled the manhole cover, there are only 2 lines that go into it and 1 line that goes out. The manhole was empty other than my line pumping water in. It wasn't pumping very fast though, it was more like a heavy trickle. The neighbor has the other line in the manhole. He kicked his pump on and it was pumping at least 5 times faster than mine. It was gushing through.

My roof is about 20' up from my septic. I could put my rotary laser level on top of the roof, then walk up the hill to the manhole with my laser receiver and wait for it to go off. I could mark the spot on the ground and go from there.

He may need a pretty high ladder. A theodolite and the math tables and it can be calculated the way a surveyor would do it. Today it is all electronic and computerized. In the long run; guessing is probably good enough. The elevation difference is not his basic problem anyway. Basics; he needs to know how his line feeds into the utility manhole. If a check valve is stuck open he may be draining other sewage back into his tank. I have seen stranger things in my lifetime.

Ron

 

[wagne223]

New one on me; never seen a BFP in a sewer line. That's what a check valve does. But stranger things have happened.

Ron

You are correct sir, I confused myself.

Been happening a lot lately.......