Sump pump discharge pipes noisy

[ctuck]

This weekend, I rerouted my sump pump discharge to another side of my house (it was discharging to the driveway and causing issues). When I filled the basin with the garden hose to test the discharge, the water in the pipes is very noisy and making swooshing and glugging sounds for 1-2 minutes after the pump has turned off (think of the sound if you turn a 2 liter bottle completely upside down and try to empty it that way).

I think I did something incorrect in my run (see attachments). Should the 12 ft run be sloping up instead of down? Should I be using 90 degree sweep elbows instead of the 90 degree elbows I'm using?

Some other info:

• Yes, I have a check valve installed in the basin right next to the pump
• Why not run horizontal straight out? If you look at the other pictures, I have to make the run rise about 1ft to go above my garage door.
• I chose to make the run go down 5ft on the interior wall for aesthetics. The alternative is an ugly pipe exterior pipe running 5 ft.

I'd appreciate any advice on what I can do to improve this run. Ideally, I'd like to keep most of the run and fix some patches, but if I need to scrap it and start over for better noise control, I'm open to that also.

 

[Terry]

I would have used sweep fittings for that. Every 90 there is a sharp right angle bend.

They also make these in white PVC
When pumping water with a pump, I have the check valve near the pump.

 

[Sponsor]

 

[Reach4]

You have a check valve, right? Fairly close to the pump is best. You don't want water from the pipe going back into the pit. The exception is that you drill a 3/16 hole in the pipe in the pit before the check valve. That will squirt water, and it is best if you angle the drill to direct the squirting down. Maybe a working check valve will help a lot of that.

An air admittance valve or vacuum breaker at the peak might help. I am not sure. That would let the downstream water exit without gurgling. I think the normal AAV is not made for that high of pressure.

Instead of 90s, you could use 45s.

 

[Sylvan]

This is why I use Cast Iron with long sweeps "the quiet pipe"

 

[ctuck]

Reach4, Yes, I do have a check valve - it's screwed directly on to the pump and then has a flexible coupling that you tighten with a screwdriver to attach to PVC so I'd have to move the check valve higher to make that work. I'll put this on my list to try.

I'll also try some of the long sweep 90s.

From my plan attached here - is it ok to have the 12ft run being sloped downward, or should I be sloping up for this run / horizontal until the exterior wall?

 

[Reach4]

Reach4, Yes, I do have a check valve - it's screwed directly on to the pump and then has a flexible coupling that you tighten with a screwdriver to attach to PVC so I'd have to move the check valve higher to make that work. I'll put this on my list to try.

The reason that little hole is recommended by the pump makers is that if the pump pumps completely dry, water could be prevented from coming in by the air. The little hole lets air out and lets the water rise into the impeller. Read your instructions for the pump, and see what that says.

From my plan attached here - is it ok to have the 12ft run being sloped downward, or should I be sloping up for this run / horizontal until the exterior wall?

You can slope either way, but you can get the gurgling as the water on the downslope tries to get out.

Those are also called vacuum relief valves. They recommend that you install them in an upright position.

 

[Chucky_ott]

I agree with Reach. Drilling a 3/16" hole in the pipe just after the pump may fix your issue.

As you stated, when the pump shuts off, the water remaining in the pipe tries to flow out. But since air can't replace the water that flows out, you get the gurgling sound similar to an inverted pop bottle.

The 3/16" hole might allow enough air to get in the pipe as the water flows out, preventing the gurgling.

Of course, drilling a hole will mean that some water will flow out when the pump runs. But it will flow in the sump pump, where it will be pumped out again.

And if it doesn't work, no harm, no foul.

 

[ctuck]

Thanks for the suggestions - will try the easy ones first and see what happens.

 

[Chucky_ott]

I'm not entirely convinced that the 3/16" hole will work since you probably need the air to come in closer to the highest part of you pipe. Sort of like how a vent prevents a p-trap from siphoning. The vacuum relief valve at that location might work better but I have no experience with them.

Frankly, I'm not sure why you would need the check valve at the pump discharge. Sure, whatever water is left in the pipe will flow back in the sump, but that should be way less volume than the sump content, no?

I don't have a sump pump but I do have an effluent pump in my septic tank. The instructions for that pump stated not to put a check valve. Whatever liquid remains in the pipe once the pump shuts off simply flows back in the septic holding tank. Whether this impacts your setup would depend on the size of your sump pit and the volume of water required between cycles.