How Much Fall On Sewer Line To Septic Tank?

The pipe that connects to it must maintain a 1/4-inch-per-foot slope toward it from the house. This means that for every 10 feet of distance between the tank and the house, the inlet must be 2 1/2 inches below the point at which the pipe exits the house.

  • Sewage lines should slope downward to the septic tank and drain field at min. 1/4″ per ft. For steep drops, a 45% slope is best. Avoid sags or sharp turns to prevent blockage.

How much drop should a sewer pipe have?

The ideal slope of any drain line is ¼ inch per foot of pipe. In other words, for every foot the pipe travels horizontally, it should be dropping ¼ inch vertically. Many drains either have too little slope or too much slope. That’s right, it is possible to have too much slope in your drain lines.

How much fall should a leach line have?

In a conventional gravity system, the pipe from the house to the septic tank, and the outlet pipe from the tank to the distribution box or leach field, should both slope downward with a minimum slope of 1/4 in. per ft. (1/8 in. per ft.

What is the correct fall for sewer pipe?

A gradient of 1 in 80 is suitable for commencing calculations for pipe schemes. If the gradient is less than 1 in 110, then the pipe could still block if the solids slow down and become stranded.

How much fall does a 3 inch sewer line need?

As a rules you should have 16th of an inch fall per foot in a pipe to achieve the slope you need for drainage. If you do that you should always be good as far as slope for drainage goes.

What is the fall of a 4-inch sewer pipe?

The minimum slope for a 4-inch PVC gravity flow sewer pipe is 1/8 inch per foot.

What is the minimum depth of a sewer line?

Building sewers that connect to private sewage disposal systems shall be a minimum of 36 inches (914 mm) below finished grade at the point of septic tank connection. Building sewers shall be a minimum of 36 inches (914 mm) below grade.

What is the maximum slope of a sewer line?

What is the maximum slope allowed? The “no” zone is anything between: 1/2″ per foot and a 45 degree angle.

How much slope does a sewer pipe need?

It is generally accepted that 1/4″ per foot of pipe run is the minimum for proper pitch on a sewer line. Larger lines such as 8″ pipe actually require less pitch due to the larger circumference of the pipe.

How much slope does a leach field need?

1. The maximum slope allowed for leach line trenches is 40% (2-1/2:1 slope). 2. All leach lines on steep slopes shall be installed in five-foot deep trenches with 12 inches of leach rock below the leach pipe or with approved chambers or other gravel-less system.

What is the fall of a 3 inch sewer pipe?

The plumbing code requires drain pipe to be sloped at a minimum of 1/2 inch per foot and a maximum of three inches per foot or vertical. A slope of less than a quarter-inch per foot will cause a lot of drain clogs and a slope of more than three inches will allow the water to drain.

What is the slope of 1/4-inch per foot?

1ft along is the same as 12 inches along or 48 qtrs. 48 along, then 1 up or 1:48 slope.

What is the slope of 1/8 inch per foot?

The slope of 1/8 inch per foot is a slope of 1 in 96.

How Much Slope for Septic Line?

This page contains information on sitework, including how much slop for a septic line to have. Peter inquires: My builder has recently completed the installation of our septic system, and I’m afraid that he did something incorrectly. The drain field looks to be at a greater height than the tank’s exit, which is consistent with this. My brain doesn’t comprehend how the tank may empty upwards. Is there something I’m overlooking? Answer: Except if you have a mound system, or another pumping system with a dosing chamber and lift pump, you are accurate in assuming that you will require a downhill slope in your sewage pipes, which is not the case.

The leach lines themselves, on the other hand, should be leveled out.

Sewage lines should be sloped downhill to the septic tank and drain field at a rate of at least 1/4 inch per foot of length.

To avoid clogging, steer clear of sags and sudden curves.

  • The fear is that the water would flow too quickly and leave sediments behind, causing the pipe to clog.
  • In situations when it is important to carry wastewater uphill, there are several different pumping system types that may be employed.
  • I would consider getting in touch with the person who created your system to discuss the problem and, if feasible, have them come out and assess the location.
  • It’s ideal if you can put your complaints in writing and send them to the contractor.
  • An upward line such as the one you describe will never function effectively.
  • Also read this article.

When Is the Best Time to Take a Perc Test? How much does a perc test cost? Who Should Be Hired for the Perc Test? After a failed perc test, should you retest? Should I use a Sand Filter with my existing septic system? Examining the condition of the wellSEPTIC SYSTEMView all articles Q and A Index

Reader Interactions

  • 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.

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.
See also:  How Do I Find My Septic Tank Document Permanent? (Solved)

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″? [email protected], 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.

  • We have a shortage of service personnel for upkeep, and I believe that a sprinkler system would be more beneficial to our grounds.
  • [email protected] That doesn’t appear to be a concern in my opinion.
  •, Yes, without a doubt, that is not hygienic.
  • [email protected], In a situation when you are just transferring a cleared fluid, there should be no particulates left behind in the wastewater stream.
  • That is a very other issue.
  • 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?
  • 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?


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 valuable aphorisms I can share, at least in the context of the building construction and mechanicals fields, is that it is extremely uncommon to come into a situation that has never been experienced 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 posted at the bottom of this page. Alternatively, consider the following:

Steep Slope Septic System Articles


Suggested citation for this web page

INSPECTION OF SEWER AND SEPTIC LINES AT STEEP SITES An online encyclopedia of building environmental inspection, testing, diagnosis, repair, and issue preventive information is available at Alternatively, have a look at this.


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Proper Pitch On A Sewer Line Or A House Drain Is Critical

Many individuals appear to be uncertain about the correct pitch to utilize when installing a sewage line or a home drain. It is also common to hear the phrase “slope,” which has the same meaning as “pitch.” It is widely agreed that a minimum pitch of 1/4 inch per foot of pipe run is required for proper operation of a sewage line. Because of the wider circle of the pipe, bigger lines such as 8′′ pipe actually require less pitch than smaller lines. However, there are also additional considerations to bear in mind when it comes to pitch.

Pitch on a sewer line for a building or home

In Queens, Brooklyn, the Bronx, and Staten Island, most residential sewage lines are 6 inches in diameter, unless they are for very big structures or for enormous quantities of rainwater disposal. In the case of a 6′′ sewer line, the minimum required pitch is 1/4′′ per foot, which is about one foot for a fifty-foot run of sewer line. It is possible that field circumstances, such as utility impediments or a lack of usable pitch, will prevent this from taking place. Generally speaking, as long as the run of pipe is built without any dips (back-pitched pipe), the sewage line should continue to work well and without the need for any substantial maintenance to be performed on it.

What many people are not aware of is that there is a limit to the maximum quantity of pitch that may be used in a sewage line that is permitted by law.

Limiting the pitch is intended to prevent waste water from entering the public sewage at a very high flow rate and interfering with the flow of waste water in the public sewer, which would be harmful.

The installation of a riser connection on the public sewage is required in some rare cases in order to reduce the quantity of pitch.

A riser is a vertical connection that is erected on top of a public sewage system to provide access. Learn more about the connections between a house’s sewage line. The New York City Department of Environmental Protection has authorized the riser diagram.

Pitch on a house drain

It is quite similar to the proper pitch on a home drain as it is on a house sewer line. The usual guideline is that one quarter inch of pitch is required for every foot of run. However, there are also more considerations to consider. When there is an excessive amount of pitch in the drain, the waste water inside the drain might flow exceedingly quickly. In some circumstances, such as when the water is running exceptionally rapidly through the house trap or the trap for a specific plumbing fixture, it is conceivable that water from the bottom of the house trap can siphon out, leaving the trap completely dry.

In order to reduce the excessive pitch of a pipe entering a sewage trap, it is recommended to utilize permissible bends.

A level aids in the establishment of proper pitch.

  1. To ensure that there is a water seal following the drain outlet of the fixture, all plumbing fixtures must be trapped separately. Double trapping of any plumbing fixture is not authorized, and all traps should be installed as near to the fixture as practicable. In order for a drain line to reach the trap, it must travel a total of 48 inches vertically from the plumbing fixture. Because waste water has higher force than the length of pipe that has been constructed, the water inside of the trap would be forced to stream out, thereby removing the water barrier. With no water barrier in place, sewage gas or other unpleasant odors can enter the structure
  2. The greatest horizontal length of pipe that can be constructed from a plumbing fixture until the trap is built is 24 inches
  3. And

Sewer and drain installations

Everyone enjoys saving money, and even more so when they can do so by doing part of the labor themselves. Keep in mind, however, the following things as well. Sewer pipes and plumbing drains are designed to survive much longer than the average person’s lifespan! When installed properly, they require little to no maintenance and do not require the usage of any mechanical equipment to function. We don’t pay much care to plumbing systems since they are normally trouble-free and reliable. Despite this, individuals continue to believe that having a basic understanding of plumbing will enable them to build plumbing systems, including sewage and drain systems.

In addition, there are safety and health concerns throughout the course of such an installation, as well as potential ramifications thereafter.

Our educational postings are not intended to be a how-to guide, but rather to serve as helpful tools for understanding fundamental plumbing principles.

Today is the day to get FREE professional guidance!

How much slope does a septic line need?

A standard septic tank has a 4-inch intake at the top, which is positioned towards the bottom. If the pipe that connects to it is not sloped 1/4 inch per foot toward it, the pipe must be sloped toward it. To put it another way, for every 10 feet of distance between a tank and a home, the tank’s inlet must be 2 1/2 inches lower than the point at which the pipe emerges from the home. The “building sewer” must be sloped (also known as “fall”) at a rate of between 1/8″ per foot and 1/4″ per foot in order to function properly (in other words thepipemustdropat least one inch for every 8 feet of sewerlineand not more than one inch for every 4 feet).

See also:  How Much Does It Cost To Empty A Septic Tank In Nys?

If you’re installing a conventional perforated pipe and gravel trench drainfield on a steep slope, you’ll need to run the trenches parallel to the fall line or along the slope itself, stepping down the slope from trench to trench to avoid damaging the soil.

Drain pipe must be sloped at a minimum of 1/4 inch per foot and a maximum of three inches per foot, or it must be vertical, according to plumbing code requirements.

Is it possible for a drain pipe to have too much slope?

Too much slope and the water speed will cause the waste it is transporting to outpace the water, resulting in the garbage remaining behind to block the pipeline. If you need to go higher than 1/2″ per foot slope, either utilize a 45-degree slope or tie into a vertical drop to do this.

Drainage and Sewer Pipe Slope

Gravity drainage and sewer pipes must have a proper slope in order for liquids to flow easily and solids to be transported away without being clogged with debris. An excessively flat pipe will obstruct the passage of waste away from the pipe. Pipes that are overly steep, it is also frequently believed, will allow liquids to flow through them so fast that particulates will not be transported away with them. Drainage pipes are often laid at the smallest feasible slope in order to allow ceilings to be kept as high as they possibly may be.

Standard Horizontal Drainage Pipe Slope

Drainage pipes should be run with a constant slope at the following minimum pitches, according to the International Plumbing Code:

2 1/2″ or smaller 1/4″ per foot
3″ to 6″ 1/8″ per foot
8″ or larger 1/16″ per foot

Large Diameter Sewer Pipe Slopes

Calculations are required for large sewage lines in order to establish the right pitch. As a general rule, sewage mains should be built to have a flow rate of 2 feet per second during periods of peak dry weather. Most of the time, flow rates are kept below 10 feet per second. It is recommended that pipes be built with anchors or other ways of keeping the pipe from moving for flow rates greater than 10 feet per second. Article was last updated on May 23, 2021. Contribute to making Archtoolbox a better experience for everyone.

How far can you run a sewer line to a septic tank?

How far do you have to run to reach the finish line? If you’re 100 feet distant, your septicinlet should be between 3 and 7 feet deep, with the first five feet providing a beautiful 5 percent gradient for drainage. When it comes to distance, the rule of thumb is to place cleanouts at a distance that is somewhat less than double the distance you can reach with a snake. From the House, a Diatance The requirements will differ from one location to another, but the standard minimum distance from the home is 10 feet.

  1. Also How do you know what size pipe goes into your sewer system?
  2. Slope the pipe at a rate of 1/4 inch per foot (at a minimum, 1/8 inch per foot) toward the tank.
  3. A standard septic tank has a 4-inch intake at the top, which is positioned towards the bottom.
  4. To put it another way, for every 10 feet of distance between a tank and a building, the intake must be 2 1/2 inches lower than where the pipe exits the building.
  5. In most cases, it is not a good idea to construct a deck near or on top of an aseptic tank.

You will be required to maintain a minimum of a 5′ setback from an underground septic system under most zoning regulations. Frost footings and imposing deckloads over a septic tank have the potential to cause damage to the tank and waste pipes.

amount of slope on septic line ?

Author Message
backattheshackMember Posted: 13 Feb 2011 15:28Replyis 1/4″ per foot ok on a 50 ft septic line? straight shot no bends or elbows
JustMember Posted: 13 Feb 2011 16:00Reply1in per 100ft. runs to mind but i’m not sure i know they are almost flat! been a while!
JustMember Posted: 13 Feb 2011 16:34Replylooked it up it’s 116 to 18 in. per ft.
MikeOnBikeMember Posted: 13 Feb 2011 16:40ReplyYeah but 1/16 is hard to measure and doesn’t tolorate settling well.I have always used 1/4 if I have the drop for it.I think it also depends on the size of pipe.
larryMember Posted: 13 Feb 2011 22:38Reply1/4 per foot is what my septic guy says. too much and liquid runs and won’t carry solid. too little and, well you know.
wec502 Posted: 22 Feb 2011 21:30ReplyI am in the ozarks.It is impossible to get a certain slope with the hills here. For pvc pipe sewer lines, as long as it goes down hill, it is fine. The PVC is slick and doesn’t catch things the way the old iron pipes did. Most of the slope/foot info is from the clay or iron pipe days. However, the drain field lines are placed to follow the contour lines of the hills and do maintain a nearly level “slope”.
islandguyMember Posted: 22 Feb 2011 21:52ReplyI ran a 20 foot line at about 1/8″ per foot. I read that you should maintain that gradient even if your slope is greater, by putting a 90 degree drop into the system, rather than exceeding the recommended gradient. Also, careful to use septic piping, its sections are designed to fit together without forming a lip. A ridge or lip can trap TP in small amounts, which will stick, dry out, adhere to the pipe wall, and trap more and more until you have a blockage. Although we have only used our system for a season, so far, so good.
lawnjoky Posted: 26 Apr 2011 10:08ReplyDown hill 1/4″ min.There are three things they teach a newby plumber:1Poop flows down hill2Pay day is Friday3Keep your fingers out of your mouth
Erins 1Mom Posted: 26 Apr 2011 16:35ReplyRecieved my cabin plans today (16 x 20); wonder if it souldn’t be bigger.I also picked up info on the infiltrator system.Will still have to have septic tank but this will take the place of the field line.If land perks (?), I will get a 30 % discount for using.Got home and realized I forgot to ask from whom.I’m such a newie; still have much to learn.
turkeyhunterMember Posted: 26 Apr 2011 21:26ReplyQuoting: Erins 1MomI also picked up info on the infiltrator system. Will still have to have septic tank but this will take the place of the field lineonly need a tank if you plan on every day use, i am using a 200 to 300 gallon plastic tank and 3 infiltrator’s.make sure you use 4 InchPVC. a local guy is charging me $300 for labor /and his trackhoe. I am buying all the materials. If you are only going up on weekends.etc. A tank is not needed. The only reason, during hunting season i may have 2 or 3 of my buds down for a hunt. And we might stay for a week, so i decided to get a small tank just to be safe.
Erins 1Mom Posted: 26 Apr 2011 21:57ReplyThere will be periods where I and possibly hubby will be spending an entire week but mostly weekends.Just got back from a plumbing class at HD, what do you guys know about “pax” hoses for water lines?
Erins 1Mom Posted: 26 Apr 2011 22:03ReplyThat should be “pex”.
turkeyhunterMember Posted: 26 Apr 2011 22:48ReplyQuoting: Erins 1Momwhat do you guys know about “pax” hoses for water lines?i like the concept.but like my pvc.cpvc.easy and simple, cheap and quick. paper towel, cleaner / primer, glue. and simple to repair if needed. i keep a 5 gallon bucket at camp with fitting/primer and glue.easy fix if something need repairing. just my 2cents
smittyMember Posted: 27 Apr 2011 12:10ReplyI used Quest Pex in my house when I redid all the plumbing.It was easy to use, good price, and haven’t had a bit of trouble with it in about 7 years now.My laundry room, use to be a back porch, and it’s not insulated well, every winter the cold line for the washer freezes up. It has never busted, or given me any trouble. I just route the dryer vent under the room and turn it on awhile and it thaws it out. But the crimp fittings have never leaked, and it has never busted from freezing.Good stuff IMHO.
toyota_mdt_techMember Posted: 27 Apr 2011 23:01 – Edited by: toyota_mdt_techReplyPex is the hot ticket now. Shark bite fittings can be spendy, but a plumber uses an expander tool, it reaches inside the pex, flares it and you slide it over the barbed fitting, it slowly collapsed back on it, done! You can make nice radiused bends, no fittings, it expands in freezing instead of split like copper and meth addicts dont steal it. It cant contact concrete or see sunlight. Otherwise, its the best stuff around.

drain pipe fall

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drain pipe fall
Author:Anonymous UserI am installing a drain from a new building to my septic tank. The problen is the building is about 12 ft higher than the tank and the terrain is a gradual terrace. How can I get to the tank and maintain proper fall?
Post Reply
Re: drain pipe fall
Author:Dunbar (KY)Come out of the building a few feet, then vertically drop with a cleanout at top with 2 45’s at the bottom of drop, then gradually follow to the septic tank.
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Re: drain pipe fall
Author:Septic Tank Yank (CO)wlw, the proper fall for the sewage main from the house to the septic tank is 1/4 inch per foot or “GREATER!”There is no problem with just following the existing slope of the ground.The minimum slope for a 4-inch PVC gravity flow sewer pipe is 1/8 inch per foot.There is no maximum limit on slope and it could be vertical.
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Re: drain pipe fall
Author:PlumberManDan (IA)Sorry CO, I have to disagree, to a point, there IS a Min and MAX fall on a building drain, min is 1/8″ per foot, and According to code UPC you do not want to have SO much fall that the pipe does not scour, Vertical OK, depending where in the line it is placed,1/2″per foot would not be acceptable depending on the length of the run whether it be city sewer or septic, the water would run so fast that it would leave the solids behind to lay there in the pipe and over time create a clog, It is good practice to keep the fall at 1/4″ per foot.PlumbermandanPost EditedPlumbCat TM 2003Plumbermandan
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Re: drain pipe fall
Author:steve (CA)Dan, what section of the UPC states that?708.0(horizontal drainage piping) states 1/4″ per foot minimum(1/8″ minimum exception for 4″ and larger with AHJ approval)718.1(building sewers) states 1/4″ per foot minimum (with 1/8″ and 1/16″ exceptions)No statements of maximum pitch.
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Re: drain pipe fall
Author:e-plumber (NY)plumbermandan (IA),This issue has been discussed numerous times in this forum.My own house is a prime example why your theory doesn’t hold water.It is located 25+ feet above the city sewer main, (which is probably about 10 feet deep in the street), the house is set back 60 feet from the street. The main drain exits the house 12″ below the basement floor.How on earth will a 1/4″ per foot pitch be maintained in this scenario? There are numerous houses all over here set up the same way.e-plumbere-plumber-“The society which scorns excellence in Plumbing as a humble activity and tolerates shoddiness in philosophy because it is anexalted activity will have neither good Plumbing nor good philosophy: neither its pipes nor its theories will hold water.” -John William Gardner 10/8/1912 – 2/16/2002Repair your leaking Plumbing fixtures ASAPThis slow drip will waste 7+ gallons of water per day.
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Re: drain pipe fall
Author:hj (AZ)It will not happen as has been proved in many laboratories over the years. I have never had a sewer rejected regardless of the pitch as long as it was greater than the minimum.
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Re: drain pipe fall
Author:Anonymous UserIn NJ we use the National Standard plumbing code. Min pitch on 4″ and above is 1/8″ per foot.(you could go 1/4″3″pipe and smaller is 1/4″ min. There is no code for too much pitch. If there was a problem I am sure there would be an addition to that section. Because these officials are allways looking for some new code to change. Job security. I have heard that theory before but I have also connected sewers 13′ to 14’deep. The way we ran it was to immediatly connect a 45 to the sewer ran it up about 9 to 10’on a 45 degree angle then backfilled up to about 4’from grade.Then 45 again straight toward the house. Never had a problem yet (10 years past)Never failed inspection for it.DM
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  • Can you tell me how far you have to run to complete the task? Your septicinlet should be between 3 and 7 feet deep, with five feet providing a lovely 5 percent gradient, if you are 100 feet distant. Cleaning out cleanouts should be placed at a distance somewhat less than twice the distance you can reach with a snake, according to general rule of thumb. From the House, a Ditance Requirements will vary depending on where you live, but a standard minimum distance from the home is 10 feet. Most of the time, the contractor will excavate for the septic tank and system at the same time as he digs the footings for the home foundation. Also How do you know what size pipe goes into the sewer system? To connect the septic tank to the home’s plumbing drains, a 4-inch-diameter Schedule 40 PVC pipe should be used. slope the pipe at a rate of 1/4 inch per foot (at a minimum of 1/8 inch per foot) toward the tank It is also possible to ask, “How do you connect a sewage line to a holding tank?” At the very top of a conventional septic tank is an entrance with a 4-inch diameter. To ensure proper drainage, the pipe connecting it to the house must maintain a 1/4-inch-per-foot slope towards it. This implies that for every 10 feet of distance between the tank and the home, the intake must be 2 1/2 inches lower than the point at which the pipe exits the house, and vice versa. A deck can be built on top of a wastewater treatment system (sewage treatment system). The construction of a deck near or on top of a septic tank is generally not recommended. You will be required to maintain a minimum of a 5′ setback from any underground septic system under most zoning regulations. Frost footings and imposing deckloads over a septic tank have the potential to cause damage to the tank and waste line.
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Sewer Drain fall question – not enough slope

Thank you to everyone for your contributions thus far. phishfood I’ve got cleanouts built up every 40 feet right now. Initially, I was under the assumption (maybe mistakenly) that if I ran 3″, I required a minimum of 1/4″ each foot in order to be successful. I understand that decreasing the diameter should keep the velocity constant, but if I reduce the diameter to 3″, can I still run it at 1/8″ every foot? Because the region where I reside is not subject to any inspections, I’m merely trying to ensure that I do everything correctly and that I don’t run into any problems.

  1. In addition to 1/4″ and 1/8″, I’ve heard the needed fall represented as a percentage of the total height of the structure (2 percent ).
  2. I was curious if one was “more accurate” than the other in terms of grammar and spelling.
  3. The formula I discovered was to take the length of the run and multiply it by the number of falls.
  4. As a result, I started by converting feet to inches.
  5. 16.50 divided by 1972.50 equals.008365 Putting the opposite side of the equation into play.
  6. It’s a good formula you used; I’m just trying to figure out if the fact that I’m translating to inches is causing my drop to be higher.
  7. However, I believe I will be unable to do this, but I will investigate further tomorrow to see what I can come up with.

What is the correct fall for sewer pipe?

Asked in the following category: General The most recent update was made on February 9th, 2020. Drain pipe must be sloped at a minimum of 1/4 inch per foot and a maximum of three inches per foot, or it must be vertical, according to plumbing code requirements. Having a slope of less than 1/4 inch per foot will result in frequent drain clogging, while having a slope of more than three inches will allow the water to flow without clogging. All horizontal drainage pipes, both above ground and below ground, should be installed at an appropriate gradient.

  1. Pipeschemes may be calculated with a gradient of 1 in 80, which is an appropriate starting point for the computations.
  2. The toilet drainpipes should be 3 or 4 inches in diameter and should slope down toward the stack at a rate of 1/8 to 1/4 inch per foot of length, or they should be perpendicular to the ground, depending on the situation.
  3. So, what exactly is a 1 in 40 chance of falling?
  4. Consider the case of a gradient of slope that is one in forty (1: 40).
  5. A 1:0.5 slope indicates that for every 1 metre traveled along the ground, the height of the slope increases by 0.5 meters.

What is a 1 in 60 chance of falling? For example, a gradient of 1: 60 indicates that there will be one unit of fall for every sixty units of patio width. Due to the fact that the patio will be 4.2m wide, dividing that distance (the run) by 60 gives the value of 1 unit of fall.


You should examine the sewer cleanout on the exterior of the home if you are hearing gurgling and all of the house fixtures are clogged. This is often a black 3-4 in color “inch ABS pipe with a threaded cap is available. Remove the cap (WARNING: BE CAREFUL! (WARNING: IT MAY CONTAIN SOME PRESSURE!) : Assuming the sewage line is completely dry, you will have a clog inside the home plumbing, directly in front of the cleanout valve. Make a phone call to a plumber and have them rooter the line. Sewer line cameras are available from several rooter/plumbing businesses.

  1. You have two options at this point: call your preferred septic provider or pull up the tank lids yourself and check the water level and solids content in the tank yourself.
  2. Most tanks erected after January 2001 include a filter that has to be cleaned at least once a year (we clean filters—please call us).
  3. We’ll even notify you once a year when it’s time to clean your filters!).
  4. It’s likely that you have a blockage in your sewage system.


Whenever you flush the toilet, the water gurgles, the toilet takes an unusually long time to flush, or the water in the shower turns brownish after you have done the laundry, you are receiving a subtle indication that trouble is brewing. In order to determine when the tank was last pumped, look through your records and then contact your preferred septic provider for assistance.


If you are experiencing unpleasant odors within your home, such as rotten eggs, it is likely that a trap or vent inside your home is not venting correctly. Call your plumber right away since these gases are harmful to both people and animals!


At times, the smells emanating from the roof vents will seep into the yard due to meteorological conditions. Make use of a plumber to elevate the roof vents and/or to place a charcoal filter in the vents, as needed. It’s important to remember that your septic tank is vented via the roof.


If you notice effluent appearing in your yard, contact your septic service provider immediately. If you see this, it indicates that your leach line has failed and you should get help right away.


Contrary to common perception, you DO need to have your septic tank pumped on a regular basis. It is possible that your system will get overwhelmed with solid waste and eventually cause damage to your leach lines if you do not perform adequate pumping maintenance.

DON’T LET THIS HAPPEN TO YOU! This is an extreme example of a tank that is overflowing. There is sewage flowing from the tank access holes and into the yard!

grease build up in sewer pipes

Fats and grease should never be flushed down the toilet or sink. They have the potential to harden the lines and cause failure; they have the potential to generate an excessive buildup of the floating scum layer in the septic tank; and they have the potential to go into the disposal regions and adjacent soils and completely block the system off. A shattered lid can pose a serious threat to both animals and children. It is possible that they will fall through the cracked or damaged lids and will not be noticed until it is too late to save themselves.

crushed or settled pipe

This is the second most prevalent problem we notice in septic systems that are less than 10 years old. In addition to blocking flow, loose fill soil surrounding the tank is causing a backup into the house since it is pulling the pipe with it as it settles. We have even observed instances when contractors installing new systems do not correctly pack the fill earth below the pipe, resulting in pipe settlement on systems that have not been utilized or have only been used for a short length of time (see below for an example).


When it comes to modern septic systems, this is the most typical issue we encounter. Take note of the fact that the unsupported outlet pipe is being driven down by settling dirt. Watch as the water level in the tank rises, forcing the flow of water in the inflow sewage line to slow. This will eventually result in a clog in the inflow sewer line at some point. The solids flowing down from the house will not be able to enter the tank correctly because of the high water level.

examples of settled sewer pipes:

INSTALLATION OF A TANK AND/OR REPAIR OF SEWER PIPESTHE “POLY” PIPEIMAGES BELOW PROVIDE AN EXAMPLE OF WHAT PIPENOTTO USES WHEN INSTALLING A TANK AND/OR REPAIR OF SEWER PIPES However, despite the fact that this grade of sewer pipe is less expensive at the time of purchase, it might end up costing you a lot of money in the long run!

settled inlet sewer pipe on unused system:

Even if the septic system has not been utilized in some time, it is conceivable that problems will be discovered during the inspection process. Pipes might settle on unoccupied ground and in yards as a result of faulty installation and/or automobiles and/or ATVs running over the pipes without realizing they are there. It may be beneficial to all parties to have a skilled inspector take a look at the system and diagnose any concerns, even though the County does not require an examination on an underused system before transferring ownership.

Roots growing in and around the septic tank:

In addition to disrupting the system by clogging or destroying drainage and distribution lines, tree roots can also enter the tank, causing it to leak. Foul odors, poor drainage, and patches of vegetation in the leach field are just a few of the signs that you may have a root problem.


Solids are kept in the septic tank and away from the disposal area with the use of concrete baffles. Using baffles to reduce agitation of wastewater entering the septic tank and prevent particles from escaping the tank and entering the drainfield, baffles can assist avoid drainfield damage and extend the life of the drainfield.

If the baffles are broken, missing, or have never been placed, the drainfield’s life expectancy will be reduced significantly. Baffle repair normally comprises the insertion of a plastic tee at the end of the sewage pipes.

orangeburg sewer pipes

Orangeburg pipe was made in Orangeburg, New York, from 1860 to 1970, and was utilized to plumb numerous septic and wastewater systems throughout Yavapai County during that time period. Orangeburg pipe is produced from rolled tar paper (wood pulp that has been sealed with hot pitch) and was considered a low-cost alternative to metal, particularly after World War II, because of its flexibility and durability. In fact, the pipe itself is so soft that professionals might cut it with a knife during the installation process!

Orangeburg, on the other hand, is known for degrading over time (it has a 50-year lifespan at the most) and deforming when subjected to pressure.

If the septic system is approved, Orangeburg will normally be stated on the permits as the material for the inlet and/or outflow pipe material, respectively.

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