Questions and answers about using pipe tees as septic tank inlet or outlet baffles or tees to prevent inlet our outlet sewer line clogging.

This article series explains the requirements for septic tank inlet tees and septic tank outlet tees and explains why the length of the tee extensions is important to prevent septic tank or septic piping clogging and to protect the life of a drainfield.

Septic Tank Tee Questions & Answers

Here are answers to questions posted originally at SEPTIC TANK TEES - please be sure to check out the types of tees and baffles, problems, and solutions discussed there.

On 2017-05-17 by (mod) - found the outlet tee floating in tank

When the tee has fallen off (Use the on-page search box at the top or bottom of this page to find our article on SEPTIC TANK TEES for details) then solids have been pushed into the drainfield: just how much was pushed and for how long determines how much damage was done.

The tee needs to be securely in place; if friction doesn't do it then use a sealant on clean dry surfaces, even silicone caulk might work though butyl may work better.

On 2017-05-17 by Deborah

I recently had our septic pumped which we do every 2 years. Our system is 29 years old and still in great shape. This time however, upon pumping he found the outlet tee floating in tank. He thought it might have fallen off during opening of the cement tank lid.

This is an old system that has a olastic outlet tee that you just push into place. It does not twist on as the new ones do. The man pushed it back into place and then told us that it should be fine. We still are worrying that it could fall off again at any time and ruin our drainfield .

Any suggestions?

Can it be glued back to secure it once in place or even use some wooden screws to screw it into place to secure it?

No damage to drainfield. Everything looked good.

On 2017-05-12 by (mod) -

The actual septic tank outlet opening is normally lower than the inlet opening - else sewage wants to back up and block the sewer line between septic tank and building. So a septic tank tee that is inserted into the tank outlet, of same dimensions as the tee inserted into the tank inlet will have its top a bit lower than the inlet tee.

As long as the septic tank OUTLET opening itself is lower than the INLET opening, and as long as septic tank tees are sufficiently above the top of the normal top of the floating scum layer, then the tee top height differences probably won't have an effect on septic tank operation.

On 2017-05-12 by Anonymous

Does the outlet tee have to be lower than inlet tee from house? Because the way tee was put back on makes it about 4" higher than when septic was originally installed. Is this acceptable

On 2017-05-10 by (mod) -

If possible I would suggest extending the T upper is so that is well above the top of the floating scum layer. That will reduce the risk of sending more solids to your drain field.

On 2017-05-10by Anonymous

Had septic pumped and discovered outlet tee was in floor of tank. Plumber said looked like settlement had caused tee to pop off.

He glued tee back on and said it is now about 12" from top because of how he had to install, but ideally should be about 16". He ran water out of outlet before putting tee on and said it didn't seem to be a problem with distribution box. Is it acceptable what he did or am I in for problems later

On 2017-04-07 by (mod) -

Yes; both an inlet and outlet tee or baffle are standard to avoid solid clogs of the inlet or outlet piping to and from the septic tank.

On 2017-04-07 by Dave

Do I need an inlet T it seems to clog up once or twice a year

On 2017-04-07 5 by (mod) re: inlet & outlet tees or baffles are indeed needed in septic tanks

Yes; both an inlet and outlet tee or baffle are standard to avoid solid clogs of the inlet or outlet piping to and from the septic tank.

On 2017-04-07 by Dave

Do I need an inlet T it seems to clog up once or twice a year

On 2017-04-03 by Margarita Villalobos

The outlet tee broke due to tank settled so a good amout of soil entered the tank...Should I be concerned since we fixed the tee and it was only dirt ?

PS...black water is coming out sprinklers...

On 2016-10-11 by Sags

What will happen if the Purifying Septic Tank outlet be close? Is it affect the work of the septic tank? How long before the septic tank be full?

On 2016-09-30 by Joe W

Hello,
I have 6, 1000-3000 septic tanks that service RV sites and cabins. I treat and stir and take care of all tanks. Recently, according to my septic guy, and it was obvious, a drain field failed. It could take no more 'stuff'. That 1000 gal tank serviced 12 RV sites well. It was rare for all the sites to be full at the same time.

How we 'fixed' this was leaving that tank there, then digging and laid pipe and connected into an second existing line. The old outlet pipe remained.

So.....This second, very lightly used line has 4 RV sites (basically no one using them) and 1 cabin that is rented on weekends, etc....

Since we did this the cabin gets invaded with odor. Now, yes, there were some cabin ventilation/plumbing issues which we corrected. Installed 3 Studor Vents. The Shower did not have a P trap and the drain vent did not go all the way up to the grate in the side of the cabin.

2004 cabin, poor craftsmanship. AND, the cabin is the last drain/edifice on a line with what is now 17 RV sites all going into a 1500 gallon tank. Since the connection, there has been no visible change or odor to that tank.

It handles the extra. Gas is escaping through the cabin side vent now (not particularly where I want it wafting over). Never before, anywhere, have we had an odor problem like this. The cabin now does not have odor, but the gasses are still present and I need to determine where they are coming from.

My thoughts are......let's go back to that first tank....the old drain pipe is still there, running into a failed drain field which (I believe) is eminenting gasses as things break down.

Could they be traveling back up to the tank? Then following flow down the new Line, past the cabin? There is no gas smell in the 2nd tank and it's in good condition. Or....that 1st tank is just sitting there, full of stuff.

We cannot detect gas there, just sewage. Basically just the water makes its way to the second tank. I understand certainly is not the preferred method of solving the whole issue. We went on advise of a septic guy, in the middle of a busy camping season, with a limited budget.

We needed a fix. So, if the gas is coming from that original drain pipe, should I cap it? Will eventually half the Park explode? Could it not be coming from there? If so, where?

Aside, the new connecting pipe (50ft long) does traverse over top of the original failed drain field. Is gas following the void created by digging for the new pipe?

Why now/where is this gas coming from? And how can I safely control it? Maybe just connect the 1st line directly to the 2nd. Instead of 1st draining into tank, and 2nd draining out.
Thank you all, this has been a nightmare (just getting the odor to stop going into the cabin).

On 2016-08-25 by royster

My liquids tank, the 3rd tank that just has liquids in it, The outlet T is a 3" PVC pipe & there is a hat on the top of this pipe,the HAT has fallen off when tank was being pumped.

There is a small flange that this hat sits on, if the Hat is plastic too, can I just use a good glue & sit the HAT back on the flanged #" PVC pipe? I don't see any other way to install the Hat other than calling a pro to discuss

On 2016-08-07 by (mod)

When you have the tank pumped it would make sense to ask your service company to open the septic tank outlet end and measure the outlet gee to see that it's within the recommended range.

On 2016-08-06 by angelo

Had plugged septic inlet line. removed tank cover and noticed original concrete baffle was broken off. Installed new inlet baffle as seen on site . noticed out let baffle was a 90 degree elbow with a down leg could not determine length (tank was full) should I change outlet baffle to meet specific as shown in site

On 2016-07-15 by (mod): do not dump sewage on the ground surface

Robert,

I'm not familiar with any situation that permits un-treated sewage effluent "overflow lines" to discharge to the surface of the ground.

And I"m not sure what "overflow" conditions are being addressed. In my book, "overflow" means "failuire" of the system or an under-designed wastewater handling and disposal system.

On 2016-07-14 by Robert goines henryville ind

My overflow line need replace I have over 3 acres. Waste goes to tank ok but will not flow through overflow lines leading away from tank

On 2016-06-15 by (mod)

A septic tank Tee serving as a tank baffle needs to be sealed where it penetrates the septic tank wall, otherwise effluent leaks out of the tank there and groundwater can leak into the tank, flooding it, flooding the drainfield, damaging the system, and potentially causing a sewage backup in the building.

On 2016-06-14 by Ed

Is the hole in the septic tank into which the baffle goes supposed to be sealed; i.e., around the baffle pipe so that no water escapes around the pipe?
Thanks.

On 2016-05-30 by Anonymous

safety tank price

On 2016-04-24 by Frank

I just bought a home in Ormond beach and had to have the "dog ear" of the 900 gallon concrete septic tank repaired. The dog ear appeared to have been repaired previously, this time the side wall broke again and we could smell sewage and notice soil settling.

As such, the company pumped the tank, then dug up around the dog ear and then re-cemented the side wall. I read all of this info after the repair and now think that I should have the T pipe installed. Inside this dog ear I noticed the 4" green pipe that led to the drain field.

The septic repair company stated that there was no lid on the top of the tank at the Outlet end, only at the inlet end. How would I install a outlet T pipe? should I pop a hole in the top of the tank to install the outlet T pipe. Can you provide some insight on how to proceed? Thanks much

On 2016-03-26 by (mod)

Anon: searching InspectApedia.com for SEWER ODORS will take you to this diagnostic article

https://inspectapedia.com/plumbing/Sewer_Odor_Causes_Remedies.php

On 2016-03-25 by Anonymous

We have sewer smell in master bath only What could be causing it?

On 2016-02-18 by (mod)

When the septic tank won't drain, the drainfield is failed and needs replacement, or there is a blocked drain line between tank and fields. Lowering the tank is not a useful approach to consider.

On 2016-02-18 by Simon

Hi. Recently moved into an old cottage. Previous owners said they weren't sue where the septic tank was, but (possibly stupidly) we bought the house anyway. One neighbour told us we don't have one and the waste flows into the river whch thankfully turned out not to be correct.

Anyway, we discovered the location of the tank when the last drain cover before the tank (just a 4" down pipe, not a proper drain) began to overflow. Before that we didn't even know that drain was there as it was under grass

. It tuns out after a lot of digging that we have a concrete/block single-compartment septic tank that had about a metre of soil and grass on top of it and it was full and the pipe was blocked. Having just had the tank emptied I now set about trying to unblock the pipe.

I put a 4" plunger on the end of my drain rods and pumped up and down for ages until the water suddenly flowed properly. All sounds good and like the problem is fixed, but what actually happened is the inlet tee blew off and is now floating around in the little bit of water that is in the tank.

What I want to know is what problems might this tee not being there cause and how much should I expect a tradesman to charge to fix it.

Obviously the actually cost of any parts is minimal, but I have no idea how long such a job should take. Also I am thinking of getting the depth of the tank increased so that it is back up to ground level and I can fill the hole in around it; is that an okay thing to do? Thanks all.

On 2015-12-12 by (mod)

Clean the surfaces and when dry you can apply a polyurethane caulk or masonry caulk or sealant. If you can't get the surfaces dry use a hydraulic patching cement.

On 2015-12-12 by neil

I need to grout around the outlet pipe on our septic. The previous owner just had a piece of 3" SDR laying in the rectangular hole. what is the best way to secure the pipe and get a patent seal?

On 2015-11-17 by (mod)

B

A septic tank is normally always full up to the bottom of the outlet pipe. That will be (usually) at the opposite end of the septic tank from the inlet.

For more details search InspectAPedia.com for FIND THE DRAINFIELD or FIND THE D_BOX

On 2015-11-16 by B

We just had our tank pumped. About a month ago, it is full again, where do we find the outlet to the weepers? Could be clogged?

On 2015-11-11 by (mod)

Stan
Send me a sketch so that I understand

Then I can comment

On 2015-11-10by Stan hale

So how do you put a new outlet baffle on if there's no opening by the outlet baffle

On 2015-11-02 by (mod)

Scum where - in the tank? sludge and scum form in the septic tank from sewage sent therein.

If you mean crud forming in the piping at the septic tank outlet: that's usually from failure to pump and waste overflowing the top of the outlet tee (a flooded septic tank) or possibly leaks around the outlet baffle or even a lost baffle or tee.

If you mean crud forming in the inlet piping near the tank I suspect a flooded septic tank (as above) or a missing inlet side tee or baffle.

On 2015-10-10 by Hunter

How does scum build up past the inlet pipe? All flows fine when the scum is pulled out of the inlet chamber, new lines, new tank, new feed. Didnt need pumped.

On 2013-01-13by Scott

What does a typical steel tank look like and are the PVC fittings the same size used in the concrete tanks? Will I have to climb into steel tank in order to get @ the outlet baffle? It looks like I may have to. In this case does the baffle need to be right close to the tank wall or could extend out as far as the tank opening so I do not have to climb in?

On 2012-09-18 by JoeB

Great website, lots of very useful information, many thanks! I am pretty new to septic tanks and we just pumped ours and were told the tank is not level and the inlet is lower than the outlet. Unfortunately I never got a chance to talk to them myself so don't know by how much. What is the typical solution? Does the tank have to be leveled or can the inlet/outlet be adjusted?

On 2012-07-01 by (mod) -

Anon: I don't know what your plumber is talking about either; but if you are discussing an exhaust fan it doesn't sound as if it has anything to do with septic tanks - which is the article above. Ask the plumber to tell you in English, or to do what other professionals do - go get the permit for you.

On 2012-06-30 by Anonymous

in my house ineed to install 1 exhaust fan the inspector tollme to get a inlet /out permit ineed to know whatthis world means

On 2012-01-28 by San Leandro Plumbing

hi there cool blog, I found your web page as I was doing some research about how to develop my website log. I was at the moment inquiring which spam plugging you utilize for comments because WE get lots on my own site.

On 2011-09-29 by Brahms

No, I didn't install the inspection port yet - needed to get the tank up and running again first. But after finding how easy it was to remove the lid with the derrick and comealong, I may not install one after all. By the way, the EF4 filter was only $15 at Southern Pipe & Supply - I was astounded.

Piece of cake. Used an A-frame derrick to lift the lid, pumped a couple of inches of water into the field lines with my submersible pump, and chiseled flush the broken concrete outlet elbow. A piece of 3" Sch 40 PVC wrapped with 1/4" x 1" neoprene foam was a tight fit in the field line, and then some 1/4" fuel line wedged in as packing. A PVC coupling to the Tuf-Tite EF4 and Bob's your uncle.

Belated thanks - other projects have intervened. Pulling off the cover as soon as my inspection port & riser arrive, replacing tee and adding filter. I'll let you know how it goes.

On 2011-09-04 by (mod) -

Gandl about the issues you describe, the article at Mor Reading at the end of this page, and additional links in our ARTICLE INDEX on "Septic TANK TEES" describe how to replace a broken tee.

When a tee has been lost, solids have been sent into the drainfield, resulting in clogging and shorter remaining drainfield life.

On 2011-09-04by (mod) - Today my son’s septic system failed.

Sorry gandl but the comment code script, in order to keep the system manageable, limits message size. I've run into that problem too. If I'm having trouble I type my comment/question in a text editor, paste it into box here, and see if it all fits.

But if you keep messages as short as the ones you already see below, your comment or question will always post just fine.

Links, dirty words, and very long messages won't post.

On 2011-09-03 by gandl2123

Today my son’s septic system failed. I will write this in bullets as my long paragraph did not post for some reason:

- Septic tank overflowed and company sucked it out says we need a new drainfield.

- Was not properly diagnosed save for looking at the scum layer high on the baffle and declaring the drain field dead. Not ready to pay 3000. Help…..

- Upon my inspection, inlet tee is broke, lifted right out as it is the old drain tile tee type 1960 era.

- Outlet tee is broke off and gone. Drain Field is plugged with “dirt?” at the outlet tee area and up the line for how far?

- I want to auger out to the distribution box and maybe even auger out the drain field. Replace the inlet and outlet tees and continue on.

- I will create a test riser on the septic tank side of the distribution box after lines are cleaned out and put 20gal of water in the drain field ever hour for an 8hr period. If it handles this load should it not be able to handle clarified effluent? Tks for your help.

I will be putting a youtube video of the inspection and liking it to this thread. Tks

On 2011-09-01by (mod) -

JM, no, provided you have safe access you don't need to empty the septic tank before replacing the baffle; but pumping the tank makes it possible to inspect the rest of the tank for damage; the fact that you're removing a METAL septic tank baffle is a red flag - you probably have a steel septic tank.

If so you might find, on pumping the tank, that the tank sides or bottom are also rusted through. If you need a new tank you won't want to have wasted time working on baffles for the old one.

Watch for getting cut on rusty sewage-contaminated metal when removing old steel tank baffle parts.

Brahms:
I agree with JMichael - you can seal a plastic tee with concrete; a problem with using some other sealants is that they may not bond to dirty or wet surfaces. A mechanical seal is fine if nothing is going to fall out later.

On 2011-08-20 by JMichel

My question is whether there is any reason to empty the tank before repairing the outlet baffle. In my case it's removal of a rusted metal baffle and replacement with a PVC T.

For Brahms: I was told yesterday to use concrete to seal any gap between the PVC and original outlet pipe.

On 2011-08-18 by Brahms

What material do you recommend to seal the gap between a PVC replacement tee and the wall of a concrete septic tank? Mortar, or some elastomeric sealant (caulk, polyurethane, plumber's putty, ???), or a mechanical seal (o-ring, oakum, ???)?

On 2011-07-24 by (mod) -

Ace, if the inlet pipes to the tank project so far in that you can't get the tee in place, you'll need to cut a bit off of the inlet pipe first.

On 2011-07-23 by Ace

that is 10 inches longer than my inlet pipes

what if my outlet tee is more than 2 to 3 inches more like 10 inches

On 2011-06-16 by (mod) -

MD:

Solids are pushed along with waste water flowing downwards from the waste line entering the septic tank, so they flow under the lower edge of the baffle and into the septic tank.

It's true that a thick scum layer forms inside the baffle, atop the liquid waste level in the tank. Septic tank pumpers call this the "pillow" - a rectangle of floating scum that they see appearing in the septic tank when the waste level is lowered (and the pillow falls down into the main septic tank area) as the septic tank is being pumped during a cleanout.

It's also true that if a septic tank is not pumped on schedule, the thickness of the pillow could begin to obstruct waste flow into the septic tank.

Pump the septic tank on schedule and the waste will flow in at the inlet, under the baffle lower edge, and the tank will work normally.

On 2011-06-12 by MD

I understand that the baffle/tee at the inlet is to prevent solids from floating back into or blocking the inlet.

But wouldn't that barrier conversely prevent inlet solids from entering the tank and start plugging up the inlet? How do the solids (toilet paper, food debris, grease, etc.) get from behind the inlet baffle/tee to the tank?

How are they kept from backing up into the inlet due to the baffle/tee?

...

Continue reading  at SEPTIC TANK TEES - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see SEPTIC TANK TEE FAQs-2 - more-recent Q&A about septic tank tees

Or see these

Recommended Articles

• SEPTIC FAILURE SIGNS
• SEPTIC SYSTEM TROUBLE: WHAT GOES WRONG
• SEPTIC TANKS - home
  • SEPTIC TANK BAFFLES
  • SEPTIC TANK TEES

Suggested citation for this web page

SEPTIC TANK TEE FAQs at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

INDEX to RELATED ARTICLES: ARTICLE INDEX to SEPTIC SYSTEMS

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