Septic drain field problem

[MichaelSen]

I have a problem with my septic drain field - water is being pumped out of the sand filter tank and it's getting to the manifold, but it's not going into the drain field, so the water level in the tank stays the same. I had the laterals jetted and scoped to confirm that at least one line was clear all the way to the ball valve (and that ball valve is open). Still, no water comes out of any of the 5 laterals. The techs claim that the pump is underpowered because the previous Zoeller N-137 died and was replaced by an N-152 which has lower GPM. But it still pumps a lot of water and there's a lot of water pressure all the way to the ball valves.

Does anyone have any ideas of what might be the issue and what to try next? I find it hard to believe that it's the pump because the rate isn't THAT much lower than the N-137, and the water isn't even trickling through. And it's going to cost $1500-$2000 to replace the pump - without knowing if it's even causing the problem.

Specs
N-137 0.5 HP
GPH @ 0 feet 5580
GPH @ 5 feet 5400
GPH @ 10 feet 4500
GPH @ 15 feet 3480
GPH @ 20 feet 2160

N-152 0.4 HP
GPH @ 0 feet 4140
GPH @ 5 feet 4140
GPH @ 10 feet 3660
GPH @ 15 feet 3180
GPH @ 20 feet 2640

 

[Twowaxhack]

It’s stopped up. Clean the pipes out

 

[Twowaxhack]

Or your field is saturated and there’s no where for the water to go. You’ll need to start at one end of your system and work your way to the other.

 

[MichaelSen]

Thanks for responding. The pipes were cleaned recently.

What I'm having a hard time understanding is this... The current pump specs don't look that much lower than what is suggested and the water gets pumped out of the tank and into the main line with a lot of volume and pressure. I scoped all of the lines and they are clear. There is a 100 ft lateral that is downhill from the manifold. I scoped it all the way to the ball valve. The ball valve looks open. I ran the pump while watching the ball valve through the scope and didn't see any water coming though the valve. If the water is being pumped into the manifold and the ball valve is open, shouldn't there be at least some water coming through?
My plan is to have the septic company excavate and uncover all the ball valves and cut into the pipes, if necessary, to track where the water is is being blocked from entering the ball valve. Is that a good strategy? It sounds better than replacing the pump and hoping it'll fix the problem, right?

When the pump is on, the water gushes out of the cut end of the manifold pipe (see video : VID_20230801_121714478.mp4). If it's a pump issue, would the water be coming out with that much pressure?

 

[Twowaxhack]

If it worked with the replacement pump at one time and now it doesn’t then either the pump is bad ( not performing to full capacity )or your system is stopped up.

You’ll have to figure out which.

 

[MichaelSen]

If it worked with the replacement pump at one time and now it doesn’t then either the pump is bad ( not performing to full capacity )or your system is stopped up.

You’ll have to figure out which.

It didn't work when the pump was replaced last September and hasn't worked since. The tech said it's probably the drain field and that I need to have it jetted. The people who jetted it said it's probably the pump

 

[Twowaxhack]

It didn't work when the pump was replaced last September and hasn't worked since. The tech said it's probably the drain field and that I need to have it jetted. The people who jetted it said it's probably the pump

It’s probably the pump.

 

[MichaelSen]

That's a possibility, but as I mentioned earlier,
when the pump is on, the water gushes out of the cut end of the manifold pipe (see video : VID_20230801_121714478.mp4). If the pump is bad, would the water be coming out with that much pressure?