How To Run Sewer Pipe To Septic Tank? (Solved)

How do you slope a sewer line to a septic tank?

  • Slope the pipe 1/4 inch per foot (1/8 inch per foot minimum) toward the tank. In this manner, how do you run a sewer line to a septic tank? A typical septic tank has a 4-inch inlet located at the top. The pipe that connects to it must maintain a 1/4-inch-per-foot slope toward it from the house.

How does pipe connect to septic tank?

Inlet & Outlet Pipes: Wastewater from your home enters the septic tank through the inlet pipe. After the solids settle out, effluent leaves the septic tank through the outlet pipe and flows to the drain field. The outlet pipe should be approximately 3 inches below the inlet pipe.

What kind of pipe goes from house to septic?

The septic tank should be positioned at least 50 feet from the house proper. ABS or PVC plastic or cast iron pipe can be used to connect the tank to the house drainage system. [We do not recommend using clay pipe nor “orangeburg” pipe.]

How deep does a sewage pipe have to be?

How Deep Is a Sewer Line? Sewer lines on private property can be as shallow as 18–30 inches deep or as much as 5–6 feet deep. In areas with cold climates, the pipe will be buried deeper to prevent freezing in the winter. Pipe depth is not always a matter of climate.

What is the fall on a 4 inch sewer pipe?

For 4-inch PVC piping and a building sewer less than 50 feet long, the minimum slope is 1 inch in 8 feet, or 1/8-inch per foot, and the maximum is 1/4-inch per foot. For sewers longer than 50 feet, the slope should be 1/4-inch per foot.

What size pipe is used for septic?

A three-inch pipe is what’s used in homes to pipe toilets. The four-inch pipe is used as the building drain under floors or in crawlspaces to transport all the wastewater from a home out to the septic tank or sewer. The four-inch pipe may also be used in a home if it’s capturing two or more bathrooms.

Why the inlet pipe in the septic tank is higher than the outlet pipe?

Level the septic tank: The septic tank inlet tee is designed to be higher than the septic tank outlet tee. This helps assure that incoming sewage clears the baffle and enters the tank correctly, while outgoing effluent does not carry along floating solids, scum, or grease (which would clog the drainfield).

How deep should a septic tank be?

Septic tanks are typically rectangular in shape and measure approximately 5 feet by 8 feet. In most cases, septic tank components including the lid, are buried between 4 inches and 4 feet underground.

Can you add a bathroom to an existing septic system?

When planning to add a toilet to your septic system, it’s important to contact the building authorities to find out if you can do it. Some jurisdictions base septic system size on the number of toilets serviced, and it’s illegal to exceed this number without upgrading the tank or leach field.

How do you seal a septic tank pipe?

The tar sealant can be used to fill the void between the concrete and pipe. Use a trowel to press the sealant into the void. If the rubber gasket is molded into the tank for the pipe, tighten it up.

Can you hook a camper up to a septic tank?

Many people who have an RV and a septic tank wonder if they can use the two together. The RV is the perfect place to allow visitors to stay while having their own space. The short answer is that yes, it is possible to connect your RV into your septic tank, but you need to make sure that you do it correctly.

What size is residential sewer pipe?

Sewer drains from laundry sinks or washing machines are 2 inches in diameter and those from sinks in the kitchen, bathroom or powder room generally use a 1.5-inch pipe. The main sewer pipe leading to the septic tank or public sewer is usually 4 inches.

How to Run a Septic Tank Line From Your House

A septic system is made up of two lengths of pipe that are connected together. Initially, it runs from the house, where the system services are located, to a tank, where the waste is separated and solids settle out. The second section runs from the tank to the drainage field, where fluids from the tank are dispersed into the earth underneath the tank. The process of installing the first run of pipe is quite similar to that of installing a traditional sewage line. It is necessary to maintain a downhill slope to the storage tank.

Locating the Septic Tank

The tank serves as the nerve center of the septic system. It is required to be situated between the residence and the drainage field. Each and every septic installation must begin with a soil test, and depending on the results, soil conditions may necessitate the placement of the tank in a less-than-ideal site for digging sewer lines. Also required are minimum setback distances from property borders, functioning wells, surface water and other obstructions to provide a safe working environment.

Tank Depth

A standard septic tank has a 4-inch intake at the top, which is positioned towards the bottom. Ideally, a 1/4-inch-per-foot slope toward the pipe from the house should be maintained by the pipe connecting to it. To put it another way, for every 10 feet of distance between a tank and a home, the inlet must be 2 1/2 inches lower than where the pipe departs the house at its lowest point. The pipe usually exits at ground level, although it may need to pass beneath a foundation footing or concrete pad in rare cases.

Digging the Trench

The trench for the septic pipe should be dug before the hole for the tank since you will need a backhoe to complete the work and the tank will get in your way if it is already in the ground. To allow rainfall to drain properly, the pipe should be placed on a 2- or 3-inch bed of drain rock, so remember to account for this extra depth when digging. It is normal to use a four-inch pipe, and it should be installed far enough down to link with the main soil stack, which is a three-inch pipe that runs vertically past the main bathroom and through the roof of the home.


Local building and health agencies will demand permits for a septic tank installation. You will also be required to submit a design plan before the permits will be provided, so prepare ahead of time. This layout should be developed in collaboration with a local builder who is familiar with the unique characteristics of the topography in your neighborhood. Stay away from planting trees or plants near the tank, drainage field, or any of the pipe systems.

They will be drawn to the pipes in their hunt for nutrition, and their roots will be able to successfully block them. You will be unable to use your septic system until the roots have been removed from the pipe. Removal may be both expensive and time-consuming.

placing the septic or sewer pipe in the trench

  • In this section, you may ask questions or express your opinions regarding trenching for Septic or Sewer Pipes.

InspectAPedia does not allow any form of conflict of interest. The sponsors, goods, and services described on this website are not affiliated with us in any way. Replacement of a sewer or septic line entails inserting a new pipe into an existing trench. When a sewer pipe, often known as a “drain line,” has to be changed, this article discusses how to install a new sewer line. Using real-world examples and photographs, we demonstrate how to diagnose and replace a clogged sewage line in an actual case study.

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Guide to installing the replacement sewer pipe line

This article on sewage line replacement discusses how to install the new sewer pipe and link it to the existing system.

  • Precautions should be taken during the excavation of sewage lines or septic lines. The maximum permitted slope for sewer or septic line pipe is recommended. Specifications for sewer or septic line trenches include homogeneity, soil compaction, and breadth. specifications for installing sewer or septic pipe into the trenches that have been excavated Size (diameter) and slope of the sewage line that should be used
  • Avoiding rocks and voids, using sand, and shielding the new septic or sewage system from damage are all important considerations.

Safety of occupants and neighbors during excavation for sewer line repairs

When the plumbers finished their work, they left a hole in the ground that was a tripping hazard for anyone who happened to walk over it. Our quick impromptu danger indications (a few wood fence pieces and a laundry basket in the vicinity) were amateurish and unsecure, but at the very least we had a visual indication that there was something to be cautious of. We next proceeded on a quest for more durable materials to use to conceal the hole until the rest of the repair work could be completed.

Safety during sewer line trench excavation

In addition, when excavators were required to leave the site between project phases, the site was marked off with yellow danger tape connected to sticks during the excavation process. People who are at risk of falling into a ditch are also warned in this way, albeit in an amateurish manner. Do not leave any site excavations open and unattended; the dangers include harm as a result of someone falling in, as well as the possibility of pipe freezing in colder climes.

What is the proper slope for sewer lines between house and septic tank or sewer main?

It is preferable for sewage line trenches to have a constant slope, with a grade ranging between 2 percent and 10 percent grade – that is, the sewer line slope can drop anywhere between two and ten feet every hundred feet of run – rather than a steep slope. You can see that the slope of the sewer line down this hillside is far too steep. A problem (which is less prevalent in plastic pvc pipes than in cast iron pipes) is that the water and particles in the sewage do not remain together, resulting in solids remaining in the piping and clogging it.

Sewer Line Trench Details: uniformity, soil compaction

Ideally, the sewage line trench bottom should be appropriately and consistently sloped and compacted in order to prevent sewer line pipes from drooping or breaking, clogging, or piping failure. A virgin soil layer should be present at the bottom of the sewage line trench – it should not have been over-excavated. However, because trenching is a sloppy craft, certain trench portions may be irregular and deeper in some places than others. To minimize future sags, it is necessary to compress the dirt used as fill beneath the sewer piping in this situation.

In addition, if trenches are not dug below the frost line, wastewater resting in a low pipe sag in a cold region may freeze, causing the system to become completely inoperable.

The Alaska Septic Installation Manual recommends that sewage line trenches be as shallow as feasible in width and that plumbing be installed on undisturbed soil or compacted backfill dirt, according to the Alaska Septic Installation Manual.

Installing the replacement sewer line

In most jurisdictions (with the exception of Alaska), the minimum diameter sewage line piping authorized is four inches in diameter. Clogging is more likely to occur in smaller lines. We’re talking about gravity-flow sewage lines in this context. Typically, sewerage is transported by a pumped or forced sewer main after having passed through an impervious surface, which allows for smaller diameter pipework to be used in residential applications. Sections of the new drain were put down the trench for installation, trimmed to length at each end, and then linked together with the existing drain system.

We connected the new drain line to the existing stub of cast iron sewage pipe that was located outside the house foundation wall at the home end that was higher up the hill.

The rubber connection that was used to connect the two drains developed a leak and had to be replaced, therefore it was necessary to reconnect them.

An askewpipe connection has a higher chance of leaking.


(2nd of February, 2012) Someone asked: What is the minimum size sewage drain line required by the International Building Code, and are 90-degree bends allowed under the code? Is there a limit to how many 90’s are acceptable? for example, 2 or 3?


Whenever possible, plumbers avoid 90-degree angles on sewer lines because they tend to clog. Use a 45-degree angle, or two 45-degree angles if you need to make a 90-degree turn. More bends than are absolutely necessary also increases the likelihood of blockage.


(5th of September, 2012) The following question was submitted by [email protected]: “What is the proper diameter of the new PVC drainage pipe to connect to the side entrance of a concrete septic tank that measures 5 3/4″ inner diameter and 7 1/2″ exterior diameter?” Moreover, what should I use to plug the entrance in an area where there is a severe root problem?

Question: connecting the new sewer line to a septic tank that was connected to terra-cotta piping

29th of March, 2015 joh hymanexplained: The terra cotta pipe that goes into the septic tank is 4 inches in diameter; how do you get it out of the tank? Is it possible to reduce the pipe size to three inches at the point where it enters the tank?

See also:  How Much To Get A Septic Tank Pumped? (Perfect answer)


Joh There is a good chance that an ancient portion of terra-cotta sewage line that enters the septic tank has been sealed with concrete. Terracotta, on the other hand, is fairly soft. You’ll need to take the following steps to get started: 1. After you have dug the tank to the point where you have enough working space, and ALWAYS WORKING ALONE since falling into a septic tank is typically fatal, you will chip off the old terra-cotta line using a hammer and a mason’s chisel. Of course, you should use goggles and other safety gear.

you will need to install a baffle or pipe tee in the tank (from the inside walll of the tank) (DO NOT ENTER A SEPTIC TANK OR LEAN OVER IT AS THIS CAN BE FATAL) The tank tee may protrude through the opened wall of the septic tank to provide a 3.

You’ll need to use a masonry sealer or cement to seal the area surrounding the pipe passageway.

Question: find the sepic tank cleanout port

Asked by Anonymous: How do you locate the inspection holes in order to get the tank pumped?


Beginning with SEPTIC TANK, HOW TO FIND THEM, we will explain how to locate the septic tank in an ongoing series of articles. At that point, you just lift it up to reveal the cleanout port(s) in the tank’s top, and you’re done. If the tank is deep, discuss with your septic contractor the possibility of installing septic tank risers before re-burying it again to make the next cleanup simpler. Reading at BED the SEWER LINE in SAND Alternatively, choose a topic from the closely related articles listed below, or browse the entireARTICLE INDEX.

Article Series


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installing drain piping on steep slopes

  • In this section, you can ask questions and express your opinions regarding sewage or septic pipe lines on steeply sloping premises.

InspectAPedia does not allow any form of conflict of interest. The sponsors, goods, and services described on this website are not affiliated with us in any way. Installing or replacing sewer lines on steep hills is a challenging task. This article discusses the construction of drain lines on steep slopes between a house and a septic tank, as well as the maintenance of drain lines. For this topic, we also have anARTICLE INDEX available, or you may check the top or bottom of the page. Use the SEARCH BOX to discover the information you’re looking for quickly.

Guide to installing the replacement sewer pipe line at Steep Sites

Using real-world examples and photographs, we demonstrate how to diagnose and replace a clogged sewage line in an actual case study. Septic or sewage line blockage and backups may be prevented by having the proper drain line slope installed. In this section, we will talk about

  • Septic pipe installed in a zig-zag pattern on steep hillsides
  • Septic pipes with a U-turn on steep hillsides
  • Septic pipework running parallel to the fall line of a slope Designing steep septic systems for sewer or septic pipe repair or new installations

When it comes to a drain waste pipe, what is the right slope or pitch to use? When wastewater travels at the proper pace via a drainpipe, the water transports solid waste, such as feces and toilet paper, as well as water, to a septic tank or sewage mains for disposal. Generally speaking, plumbing rules and wastewater piping guidelines state that building drains should be pitched at a rate of 1/8” to 1/4” of slope for every foot of linear length or distance. Problems associated with steep dips between the home and the septic tank include: A steep building site, such as the one depicted in our page top photograph, can result in a significant drop in elevation between a building main drain and the septic tank inlet opening (or sewer main connection), resulting in waste piping slopes that exceed the recommended limits for slope in the waste piping.

If waste passes through the sewage line at a rate more than 2 fps, there is a possibility that water will leave sediments behind in the pipe, resulting in recurring obstructions.

If waste runs through a septic or sewage drain line at a slower rate than the required rate, there is a risk that the listless flow will deposit sewage in the pipe, causing it to get clogged.

ZigZagging Drain Line Piping Down a Slope

zigzagging the pipe down a steep slope, making multiple bends, would be one method of reaching the required wastewater flow rate in a drain line down a steep slope. However, in my opinion, the increased number of turns and length of this approach may increase the likelihood of future sewer line blockages. Additionally, the zigzag drain line approach will make it more difficult to clean out blockages, and therefore you will need to include sewer line cleanout access points at every run and turn in the installation.

Straight-run Drain Line Piping Down a Steep Drop Slope between House and Septic Tank or Sewer Main

According to my observations, many waste line contractors simply establish a straight sewer line from the home to the septic tank or from the house to the sewage main, regardless of the building slope, as long as we have at least 1/8″ per foot, ideally 1/4″ per foot, or more, of water pressure. Drain lines with a lower slope or those are practically flat are more likely to clog. On a related note, if you’re building a drain line that may be too steeply sloped and you won’t be able to readily correct the problem, make sure to include extra cleanout access ports.

Experience in Installing Steep Sewer Drain Line Piping

It is my opinion that if the whole pipe run is steeper than what is generally specified, it is possible that you will never see a clog occur. The sewage line dips on a slope between 2″ and 3″ per foot over a 40-foot run between the home exit line and the septic tank entrance baffle at the property depicted in these images and in the other photos in this series on sewer line replacement, as seen in the other photos in this series. In order to avoid leaving particles behind while flushing the toilet, this house-to-septic tank drain pipe should be placed in the “risk zone.” However, after managing this property for more than two decades, we can confidently state that we have never had an issue with too-rapid drainage clogging the waste line.

Since we replaced the old clay plumbing with plastic piping, we have not experienced any sewage obstructions.

The black line on the right-hand pipe portion indicates to the installer when the pipe sections have been completely connected together.

The only issue we experienced with the line was when the previous clay line was smashed and subsequently became clogged with mud and other debris.

Other Steps to Avoid Problems with Septic or Sewer Drain Lines on Steep Sites

  • Cleanouts of septic tanks or sewer drain lines: I’d put external cleanout access ports on the sewage line every 20 feet or so for the sake of ease. Proper septic pipe hookups include the following: Ensure that the new pipe connections are made correctly, that they are lubricated, and that they are completely seated during the assembly process. The following are the proper sewage pipe directions: The receiving pipe hub, often known as the “female” end of the pipe, is located at the bottom of the following downhill segment. Make sure you don’t do this in reverse or you’ll attract leaks and blockage in your sewage system.
  • Smooth drain line connections should be employed: the hub-less drain pipe connector shown in our photo was used to connect the new plastic waste line (which runs downhill to the septic tank) to the old cast iron waste line at the point where it exited the structure. These pipes needed to be correctly aligned (to avoid leaks at the connector) and their connections and pipe ends needed to be filed smooth in order to reduce the likelihood of waste line clogs at this point in the system.

Installing SepticDrainfieldPiping on Steep Slopes is a Different Matter Entirely

Please understand that we have examined the installation of solid plumbing between a building and its septic tank or sewage main in this articleand that higher slopes may be acceptable in some circumstances. However, the possibility of a “OK” for steep drain pipe does not apply in any manner to the perforated piping put in a septic drainfield gravel trench, which is a different story.

Those looking for help on installing a septic system on a steeply sloping or rolling site should check out the following articles:

  • For further information, see AEROBIC SEPTIC SYSTEMS, ATUs, and HOME – some of these systems can be used on steep slope locations. Or SeeHOOT Aerobic Systems Drip Disposal Design and Installation Guide for more information. Alternatively, see “Guidance for the Design, Installation, and Operation of Subsurface Drip Distribution Systems as a Replacement for Conventional Title 5 Soil Absorption Systems for the Disposal of Septic Tank Effluent,” published by the Massachusetts Department of Environmental Protection in 2006 and refining Massachusetts regulations 310 CMR 15.240, 15.242, 15.247, and 15.280-15.289
  • Or “Guidance for the Design, Installation, and Operation of Subsurface Drip Distribution Systems as SYSTEMS DE DOSAGE For hilly sites where the drainfield must be located either uphill or downhill from a septic tank or structure, PRESSURE is a term that refers to pressure dosing systems that may be beneficial for disposing of sewage. GRAVELLESS SEPTIC SYSTEMS – Other gravelless systems are capable of handling mild bends required to follow rolling slope lines
  • However, some gravelless systems are not. A system that will be required when the elevation of a structure or a septic tank is lower than the elevation of the drainfield or sewer main is Septic pumps, sewage ejector pumps, grinder pumps, effluent pumps, sump pumps, septic pumping stations, and septic pump alarms Installation of septic drainfields on steep or rolling terrain is described in STEEP SLOPE SEPTIC DESIGNS, which is part of the SEPTIC DESIGNS section.

Reader Q A – also see the FAQs series linked-to below

@hello there, dude. Sweep turns with a wider radius (e.g., 2 45s) will often flow better than sharper turns. On a corner where the toilet waste flow is present. If trenching provides for 4″ deeper depth, is it preferable to construct the 90° corner with a 1° drop rate as normal, or is it preferable to make the corner with two 45° corners while lowering the 4″? Thanks@Ted, Start by consulting with your local building or health department to see what type of design would be considered suitable in your nation and neighborhood.

  1. We have a shortage of service personnel for upkeep, and I believe that a sprinkler system would be more beneficial to our grounds.
  2. Thanks@Ted That doesn’t appear to be a concern in my opinion.
  3., Yes, without a doubt, that is not hygienic.
  4. Thanks@Ted, In a situation when you are just transferring a cleared fluid, there should be no particulates left behind in the wastewater stream.
  5. That is a very other issue.
  6. What if it’s been sitting in a septic tank for a while, breaking down as if it were going to a leach field instead?
  7. That would be the material that would be sent to the aerobic tank.

You may be required to utilize a grinder sewage pump and force main; we are in the process of establishing a traditional tank close to our home.

What is the maximum percent drop per foot for the effluent line in terms of percent drop?

See also:  How To Mark A Septic Tank Lid? (Solved)


Thank you very much.

It goes without saying that such lines must have the proper pitch in order to reach the final position of the septic tank.

You should verify with your local building authority to find out exactly what is required to be placed at a 4 foot depth in your area.

My issue is, can I dig a smaller trench and then descend vertically to the requisite four-foot depth before finishing?

Thank you for the information, it was really useful.

What would be the best configuration for the septic tank and pipes when the designated drain field area is 500 feet away from the house?

The slope before and after the hill is rather level, descending very gradually in the direction of the drain field before becoming steeper.

A construction site located in a swale below the city sewer lateral service point has been identified as a potential concern.

(Let’s pretend it’s 8 feet below the surface) Is there an alternative to the brute force strategy of bringing in hundreds of cubit yards of fill and compacting it to raise the elevation of the construction site?

A septic tank is just 18 inches away from the building foundation, which is a little near.

Solids dropping vertically have the potential to adhere to and clog the pipe; however, employing 45-degree elbows instead of 90-degree elbows can help to mitigate this danger.

I would begin by having the tank examined to identify which items are most important in this order of significance.

A sound septic tank, as opposed to one built of brick or rusted steel; how well the baffles and protection from groundwater leaks are maintained; and how well the baffles and protection from groundwater leaks are maintained.

The quality and capacity of the drainfield are important considerations.

Is this a reasonable drop?

This is an ancient septic tank that I was allowed to utilize because of a grandfather clause.

What is the length of the pipe drop when the septic tank is 120 feet away?

How steep do the pipes have to be from one drop box to the next?

Does the length of the pipe, in addition to its angle of incline, have a limit in terms of length?

Please let us know if this is the case!

Verne, you have an issue with a septic or wastewater system that has too much downslope.

The difficulty with longer segments of excessive slope sewer plumbing is that the liquid waste will occasionally overtake the solid waste in the line, causing the system to back up.

One of the most useful aphorisms I can share, at least in the context of the building construction and mechanicals fields, is that it is extremely rare to come across a problem that has never been encountered before.

According to one of the solutions described on this page, the sewage line is made even longer by zig-zagging across the steeply inclined areas of the land.

I’ll leave the graphic specifics to your imagination, so go ahead and go creative.

Let’s put the question to your septic installer and see what she has to say about it.

STATIONS FOR PULLING OUT SEWAGE Hello, I have a question concerning the installation of a toilet in a cabin that is around 300 feet from the main home, septic tank, and field.

Is too much slope a concern in this circumstance, given the considerable distance that the effluent must travel to reach the tank?

Do you think that building a sewage pump would make any difference in this circumstance, considering that the septic tank is located downhill from the toilet?

There should be a thorough inspection of the whole sewage line (perhaps using a sewer camera), and any slope issues should be addressed.

It’s always filled, no matter how long you wait.

Is it necessary to have the angle coming out of the home re-done?

What type of valve is used to connect the pump to the drain field?

Alternatively, seeSEWER / SEPTIC LINES for STEEP SITES FAQs- questions and answers that were originally placed at the bottom of this page. Alternatively, consider the following:

Steep Slope Septic System Articles


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How to Tie Into an Existing Septic Tank

Adding more input lines to your current septic tank is a viable option if your tank is working properly and is much below its maximum capacity for consumption. If you want to do this, you will need to integrate the new addition into the old system without causing any disruptions or changes to the existing system. The difficulty of this work will be greatly influenced by the location of the new addition as well as the technique of installation employed for your existing systems.

Step 1

Determine the location of the drain pipe that runs from the present residence to the septic tank. This may be accomplished by locating the main drain line beneath your property and recording the locations where it passes beneath or through the foundation. Move along this line outside the house until you are roughly eight feet away from the house, then turn around. Continue digging until you reach the drain line. There should be no more than 24 inches in depth below the surface of the ground for the line, which should be a 4-inch pipe.

Step 2

You should dig until you have exposed roughly three feet of the drainpipe once you have found it and marked it with chalk. In addition, you will need to dig down a little bit to provide access all the way around the pipeline. To get to the start point of the new field line, dig a ditch from this point onward. This ditch should be constructed in a straight line and at a small gradient from the current drain to the starting point of the new drain system. Remove any big boulders or roots that may have accumulated in this ditch.

Step 3

PVC pipe sections of four inches in diameter should be laid from the new drain point to the old drain line. Before applying PVC cement, make sure that all pipe ends and fittings have been cleaned using PVC pipe cleaner. Connect the drain line to the new drain point, ensuring sure that all of the fittings are securely fastened to the pipe.

Once you have verified that there are no appliances running in the house, use the hacksaw to cut through the current drain line. Using a sharp knife, make two incisions roughly six inches apart. Clean both ends of the aperture thoroughly, removing any burrs or tiny bits of pipe that may have formed.

Step 4

Insert the tee fitting into the hole that you just made in the wall with your fingers. Because the drainpipe and fitting will be a very tight fit, you will need to flex the drainpipe and wedge the fitting into position. Before installing the fitting, thoroughly clean the fitting and pipe ends. You will need to move rapidly once the cement has been applied in order to get the fitting in place since the cement will harden very quickly. Make the necessary adjustments to the fitting so that the new intake is directly in line with the new pipe.

Check that all of the fittings are in place before back-filling all of the ditches.

How to Connect Pipes to a Septic Tank

Septic tanks are connected to dwellings by four-inch pipes. Image courtesy of dit26978/iStock/Getty Images. Most contemporary septic tanks, whether constructed of concrete or plastic, are divided into two compartments by an internal baffle and equipped with an intake and output port. In most cases, when you first install the tank, each port has a preinstalled 4-inch sanitary tee fitting. You connect the waste line from the building to the inlet fitting and the drain line to the outlet fitting either by gluing it or by using a mechanical flexible coupling to connect the two lines (often referred to as aFernco coupling).

  • Septic tanks used to have only one chamber in the olden days.
  • The scum layer contains greases, oils, and other lighter-than-water contaminants that could clog the soil.
  • Whatever your feelings about the necessity of the tees, they serve as an insurance policy against the failure of the septic tank baffles, and it is smart to have them installed.
  • In order to keep debris out of the pipes, some plumbers put grates on the top portions of tees.

How to Install Septic Tees

The installation of the tees on the septic tank must be done from the inside of the tank if the tees do not come with the tank. A 4-inch tee is normally firmly secured by predrilled or, in the case of concrete tanks, preformed holes in the tank’s inlet and outflow holes. A bead of butyl or silicone caulk around the perimeter of the tee on both sides of the tank will enough in most cases, but it’s not a terrible idea to apply some in case you do need glue. The top of the tee should have a short piece of tubing attached to it to allow the aperture to extend over the scum layer in the tank, while the bottom of the tee must extend below the scum layer, or around 2 feet below the tee, to allow for proper drainage.

You may either attach a length of 4-inch pipe to the tee to extend the bottom or install an aseptic tee pipe, which often contains an internal filter, to do this.

Connecting Inlet and Outlet Pipes

The waste and drain pumps are located in trenches that slope toward and away from the tank, respectively, with a slope ranging between 2 and 10 percent. For a modest slope, it’s fine to glue the pipes straight to the tee; but, if the slope is steep, you need glue a 22 1/2-degree bend onto the tee to make the glue connection completely waterproof. If necessary, the bend can be configured such that it faces upward on the input side and downward on the outflow side. Despite the fact that the pipes fit firmly in the fittings, it is necessary to glue them together.

A septic tank may be deadly, and falling into one or even peering into one too closely can be fatal.

How to Install Drain Pipes for a Septic Tank Yourself

Home-Diy Installing a septic tank is often done by a professional who has access to the necessary equipment. A concrete septic tank can weigh several thousand pounds, and the ordinary homeowner does not have the necessary tools to safely install it in the ground. if (sources.length) then this.parentNode.removeChild(sources); else this.onerror = null; this.src = fallback; if (sources.length) then this.parentNode.removeChild(sources); else if (sources.length) then this.parentNode.removeChild(sources); else if (sources.length) then this.parentNode.remove ‘/public/images/logo-fallback.png’) is a fallback logo image.

A concrete septic tank can weigh several thousand pounds, and the ordinary homeowner does not have the necessary tools to safely install it in the ground.

  • The following items are required: Shovel (backhoe is recommended)
  • Tape measure
  • Gravel
  • Rake PVC perforated pipe
  • PVC pipe cleaner
  • PVC pipe cement PVC pipe cleaner
  • Geotextile material
  • Hacksaw


Large bushes or trees should not be planted directly over drain lines.

  1. Inspect your property and get a percolation test performed. In most cases, you will need a copy of the perc test results in order to acquire a permit to build a septic system in your home. In order to assess how quickly the soil absorbs water, a perc test will be performed on your site by a licensed specialist on your behalf. The results of this test will be used to calculate the quantity of drain line that will be required for your system. Drain lines should be measured and marked out before installation. You can divide this down into many lines, but each line must be the same length, and there must be a minimum of six feet between each line in order to be considered complete. Prior to digging, mark the beginning and ending locations of each line, double-checking all measurements to ensure they are accurate. Dig each drain line to a depth of 30 inches and a width of 24 inches. However, while a pick and shovel may be used to do the task, a backhoe can complete it in a fraction of the time and with less strain on your back. To make the trenches as flat as possible, remove any large boulders or roots that may have accumulated in them. Each of these lines will be served by a pipe that will go from the distribution box to it. This is the location where the pipe from the distribution box enters the ditch and marks the beginning point of your drain line. Fill each drain line with gravel until it reaches a depth of 12 inches. Spread gravel over the area to be covered with drain pipes and smooth it up with your rake. Install a 4 inch PVC perforated pipe on top of the gravel to provide drainage. This pipe will be connected to the pipe that comes from the distribution box and will run the whole length of the drain line to connect to the drain. Pipe cleaner should be used to clean each pipe junction before applying pipe cement. Before continuing, double-check that all of the fittings are in place. To finish covering the drain lines, continue to pour additional gravel into the system until the pipes are covered by roughly 1 to 2 inches of material. Using a rake, smooth out the gravel. A layer of geotextile material should be rolled out to cover the whole length and width of the drain line in order to prevent dirt from filtering into the drain lines and to aid in keeping roots out of the drainage system. The drain lines should be backfilled somewhat to allow for some small mounding to compensate for the settling that will occur. Grass seed should be planted on top of drain lines to aid in the absorption process and to avoid erosion.
See also:  What Is Septic Tank Pumping? (Best solution)

The Drip Cap

  • Installing a septic tank is often done by a professional who has access to the necessary equipment. A concrete septic tank can weigh several thousand pounds, and the ordinary homeowner does not have the necessary tools to safely install it in the ground. Dig each drain line to a depth of 30 inches and a width of 24 inches. Ensure that any large rocks or roots are removed from the trenches, and that the foundation is as level as possible
  • Fill each drain line with gravel until it reaches a depth of 12 inches. In addition, this pipe will link to the pipe that comes from the distribution box and will run the whole length of the drain line.

How to Install a Septic Tank with Drain Line

It is discussed in this article how to set up a septic tank with a drain line. A three-compartment septic tank is covered in detail in this project, which includes all of the processes required to complete the installation. This septic tank has adequate capacity to accommodate 4-6 people, making it an excellent choice for most households. Even if the installation is straightforward, you will need to rent a mini-excavator or, ideally, a backhoe digger to do the job properly. It is important to exercise caution when using detergents, disinfectants, or other acid cleansers since they will interfere with the operation of the bacteria that decompose the waste materials.

A simple explanation for how the system works is that the majority of the trash is transformed into sewage water.

Every two years, you will be required to remove the solids from the system.

The sewage water will be discharged from the septic tank into the header pipe and then into the perforated drain pipes after passing through the header pipe. The water will then be able to seep into the soil through the gravel layer.

Made from this plan

The construction of the sewage lines from the home to the site of the septic tank is the first step in the project’s development. Excavate the trenches such that the pipes have a 1/8 inch dip each foot of excavation. The pipes must be placed on a bed of sand and then completely covered with sand. The sand will protect the pipes, and it will also serve as an excellent marker for future operations, should it be necessary to dig further trenches. Decide on the position of the septic tank and mark the area with a marker.

  1. Furthermore, the depth of the hole will be decided by the size and placement of the septic tank as well as the location of the sewage line.
  2. We also employed a dumper truck to remove the soil from the site.
  3. Make certain that the sewer pipe has a 1.5 percent slope when it is installed.
  4. We relocated the septic tank with the help of a backhoe digger after securing it with a heavy-duty strap and moving it.
  5. Check to verify that the septic tank intake is compatible with the sewer pipe.
  6. We used a spirit level to ensure that the tank was upright during the installation.
  7. Sand should be poured around the tank.

If you do not fill the tank with water, it will collapse due to the weight of the earth on top of the container.

We will not be constructing a drain field for this project, but rather an 80-foot-long trench.

You may either construct two 40-foot-long trenches or a wide surface area and install three 25-foot-long drain pipes on it.

We connected the header pipe to the septic tank, ensuring that it had a 2 percent slope to prevent backflow.

Because it will move quite swiftly, using a backhoe digger is highly recommendable.

Trenches should be filled with gravel to the point where the drain pipe (which is normally 4′′ in diameter and perforated) has a 1/8′′ per foot slope.

Using a 4′′ layer of gravel, cover the drain pipe and make sure the surface is level.

Geothextile cloth should be used to cover the trench.

Because the fabric prevents the pebbles from becoming mixed with the soil and clogging the drain pipe, it is effective.

At the end of the drain pipe, you must add a vent pipe to provide for proper ventilation.

This also allows for simple access to the drain pipe in the event that it has to be cleaned.

We moved the earth that we had dug back into the trenches with the use of the backhoe’s front loader bucket and a rake.

First and foremost, you must connect the riser to the septic tank.

In order to have easy access to the tank for maintenance and inspection, the top of the riser should be slightly above the level of the surrounding ground.

These sheets are thin and rather stiff, despite their small weight.

As a result, you must first cover the tank with these sheets, followed by a 4′′ layer of dirt on top of that.

The polystyrene sheets must be covered with dirt once they have been laid out on the ground.

Work carefully so that you do not harm the tank.

On the blog, you can also get a comprehensive guide on how to construct a concrete pump house.

Make sure to read the previous articles in the Brick House Construction Series to see what more is in store for you!

We appreciate you taking the time to read our article on how to construct a septic tank with drain line, and we encourage you to go through the rest of our projects. Please spread the word about our articles to your friends by using the social media sharing buttons.

Related Posts

The construction of the sewage lines from the home to the site of the septic tank is the first step in the project’s progression. Constructing the trenches with a 1/8′′ per foot dip in the pipes is essential. The pipes must be placed on a bed of sand, and the sand must be used to completely cover them. Besides serving as a protective barrier for the pipes, it also serves as a useful marker for future projects, should it be necessary to dig more holes. Select a site for the septic tank and place a marker in the vicinity.

  1. Making the hole took around three hours with a backhoe digger.
  2. The depth of the excavation for the septic tank will be determined by the sewer pipe.
  3. It is necessary to fill the hole with an 8-inch layer of sand.
  4. We positioned the septic tank within the hole and then moved it down to the sand bed below the surface.
  5. If this is the case, remove some or all of the sand from the hole’s bottom.
  6. Make sure that the tank’s top is absolutely level as well!
  7. IMPORTANT: It is now time to fill the tank with water, which should be noted.

Following that, we excavated a trench for the header pipe to be installed.

How your property is configured will determine how long you will have to wait.

This is why we chose the longer drain pipe: it was more compatible with the property’s overall design.

We next excavated a hole for the drain pipe that was 24 inches wide and 7 feet deep.

To ensure that the effluent is evenly dispersed into the soil, you should put gravel around the trench.

Gravity will direct the effluents (clean water) from the septic tank down the drain pipe, which will then direct them onto the gravel bed below.

Covering the pipe with gravel is critical because otherwise the openings in the pipe might become blocked, reducing the effectiveness of the system.

Keep this step in mind at all times.

Repeat the procedure for the remainder of the trench.

As a result, the system is dependent on it.

Cover the trench with geotextile cloth before laying the gravel.

The septic tank riser must be taken care of once you have filled in the trenches with earth and leveled everything back to its previous form.

Because of the depth of the tank, the height of the riser will differ.

Cover the septic tank with polystyrene sheets to keep it from leaking.

Earth cannot be used to cover the tank since the weight of the soil will cause the tank to collapse.

To fit the sheets around the riser, you will need to make the necessary cuts with a saw.

The earth was leveled with the help of a backhoe.

Please see this page for a list of all my home improvement efforts.

In the following year, I planted the lawn, and as you can see, the septic tank is no longer visible.

We appreciate you taking the time to read our post on how to construct a septic tank with drain line, and we encourage you to go through the rest of our projects for further information.

Please spread the word about our articles to your friends by using the social media sharing tools on our website.


When you are standing close to your leach field, which is the vast area where your septic tank is buried, you will be able to tell whether there is a problem with your septic tank. Septic-treated waste from your septic tank trickles onto the leach field, where it is spread into the surrounding soil. If the area around your drain field seems to be significantly greener than the rest of your yard, you may be experiencing septic tank troubles. Whenever the soil in and around the septic tank becomes mushy, pooled, or muddy, stay away from the area and contact your plumber immediately.

The gurgling sound indicates that there is a problem with your drainage system.

Homes with sluggish or non-functioning septic systems will begin to smell like rotten eggs or sewage gas as a result of the scent.


Your family takes a lot of showers, does a lot of laundry, and runs many dishwasher loads every day, is this the case? It’s possible that your septic tank isn’t big enough for your wastewater capacity. Although the Louisiana Department of Health authorizes 500-gallon, single-chamber septic tanks for smaller residences, the department advises that double-chamber or successive single-chamber tanks be installed wherever practical. If your leach field is capable of supporting the additional tank flow, you may be able to increase the amount of waste your septic system can handle.

Tanks can also be shifted, resulting in them not being level or not working in the proper direction.

Ideally, air should fill up the top 15 percent of the septic tank’s entire inner height, while the bottom liquid should not reach over 85 percent of the tank’s total inner height.

Sluggish septic system performance can eventually result in backup into your home’s internal water supply lines and plumbing fixtures.


If your septic tank has been flooded as a result of storm-related flooding, you must wait for the water to drain before proceeding with any work surrounding your leach field. A soft leach field will not provide enough protection for buried septic equipment. It is possible that pumping a flood-submerged tank will break the pipe connections, resulting in the tank popping out of the earth. Reduce your family’s water use until your septic system is back up and running, and then plug the septic system.

It is against the law to throw waste water into any creek, stream, or other waterway.

In many circumstances, removing roots, blockages, and debris from your septic lines will be sufficient to rehabilitate your septic system after floods.

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