Septic tank tee top grate (C) Daniel Friedman Jerry Waters Septic Tank Inlet & Outlet Tee FAQs
Q&A about septic tank tees

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Septic tank tee questions & answers:

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 describes the methods of septic tank baffle repair by the installation of replacement septic tank inlet and outlet tees.A septic tank replacement "Tee" is simply a standard plastic pipe in the shape of a "Tee", typically 4" or 6" in diameter, that is inserted at the septic tank inlet or outlet to serve the function of the original septic tank baffle that may have been damaged or lost.

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Septic Tank Tee Questions & Answers

Septic tank tee replacement inserted into the septic tank sewer line (C) Daniel Friedman Jerry WatersHere are answers to questions posted originally at SEPTIC TANK TEES

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.

On 2017-04-07 21:18:12.425145 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 18:43:03.117039 by Dave

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

On 2017-04-03 09:08:27.152535 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 ??? water is coming out sprinklers...

On 2016-10-11 07:10:16.417262 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 10:44:01.705015 by Joe W

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 17:02:29.702235 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 16:09:10.183292 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 23:34:08.134144 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 17:01:12.443388 by (mod)


I'm not familiar with any situation that permits 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 06:51:28.071826 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 00:55:50.673174 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 21:01:39.939915 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?

On 2016-05-30 16:18:15.184210 by Anonymous

safety tank price

On 2016-04-24 22:57:32.935223 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 12:36:12.242636 by (mod)

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

On 2016-03-25 23:27:27.556817 by Anonymous

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

On 2016-02-18 14:14:15.736363 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 11:50:29.629725 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 15:14:25.020303 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 03:56:11.277742 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 02:28:14.838156 by (mod)


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 for FIND THE DRAINFIELD or FIND THE D_BOX

On 2015-11-16 13:20:14.824415 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 02:43:51.106164 by (mod)

Send me a sketch so that I understand

Then I can comment

On 2015-11-10 23:43:35.185988 by 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 22:45:48.218619 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 14:57:22.879834 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.


Continue reading at SEPTIC TANK TEES or see the more basic OEM SEPTIC TANK BAFFLES and their problems that can lead to need for replacement or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.




Or see SEPTIC TANK LEVELS of SEWAGE for details on normal and abnormal levels and what they mean.

Or see these

Septic Tank Care Articles

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