What Happens If A Septic Tank Is Too Sloped? (Best solution)

Inadequate slope or sags in the drainage pipes can lead to clogs and long-term performance problems. An uphill line like you describe will never work properly.

  • Septic drainfields that treat and dispose of clarified wastewater effluent using gravity need to be properly pitched and never sloped too steeply. Otherwise effluent will run too quickly to the low end of the drainfield line and gravel trench where it is likely to simply break out to the property surface.

Can you install a septic system on a slope?

If you have to install a conventional perforated pipe and gravel trench drainfield on a steep slope you’ll need to run the trenches along the slope or parallel to the fall line, stepping down the slope from trench to trench.

How much slope should a septic line have?

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. 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.

Do septic lines have to be straight?

My experience is that many waste line installers simply install a straight sewer line from house to septic tank or house to sewer main, regardless of the building slope, provided that we have at least 1/8″ per foot, preferably 1/4″ per foot, or more. Lower slope or nearly-flat drain lines are more likely to clog.

What happens when you have too much slope in drain pipe?

“Oversloped pipes (greater than ½ in. per ft.) are as likely to clog as undersloped ones because the liquids move too fast and leave the solids behind.” Why it’s costly: Without the proper slope, drain lines may clog more frequently.

How deep are septic lateral lines?

A typical drainfield trench is 18 to 30 inches in depth, with a maximum soil cover over the disposal field of 36 inches.

Can a leach field be on a slope?

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.

How much slope does a toilet drain need?

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.

Can I level my leach field?

Yes you can. You just have to ensure that the the surface level of the septic flushes with the ground level so that the storm water doesn’t get in it.

What is the minimum slope for water drainage?

For efficient drainage, paved surfaces should have a minimum 1-percent slope. Turf or landscaped areas should have a minimum slope of 2 percent.

How deep should your sewer line be?

On average, trenches should be around 12-24 inches-deep, and wide enough to house your pipe comfortably before filling it in with soil and sod. As we’ve mentioned, in cold weather regions, this will need to be deeper or you’ll have problems with your sewage freezing.

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.

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.

Can you have too much fall in sewage pipe?

There is no such thing as too much fall. A drain pipe can drop at a 45 degree angle if needed. plumbjobber Buddy, the myth of “too much fall” in a sewer pipeline is exactly that, a myth.

How much should the ground slope away from a house?

Ideally, the ground should drop one inch for every one foot that you move away from the house for the first 5-to-10 feet around your house. While this is not always possible, the ground should never be sloping upwards as you move away from your house foundation.

What is the maximum slope on a drain pipe?

The maximum slope for efficient drainage is usually a drop of 1/2 inch per 1 foot of horizontal distance. A pipe with a very extreme slope of 45 degrees or more is considered vertical. Vertical pipes, or stacks, drain solids and liquids effectively.

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.

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

zigzagging the pipe down a steep hill, making multiple bends, would be one method of reaching the required wastewater flow rate in a drain line on 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, or it may be necessary to include sewer line cleanout access points at each run and turn in the installation.

Overall, zigzag pipe running downhill is more expensive, has more twists that increase the likelihood of clogging, is more difficult to clean out, takes up significantly more area on the job site, and is not often installed by contractors.

Experience in Installing Steep Sewer Drain Line Piping

It may be necessary to zigzag the pipe down a steep slope in order to get the required wastewater flow rate. My OPINION is that the additional turns and length of this approach may increase the likelihood of future sewer line blockages; the zigzag drain line approach will also make it more difficult to clean out blockages; or you will need to add sewer line cleanout access points at every run and turn in the installation. In brief, a zigzag pipe ran down a slope is more expensive, has more turns that increase the likelihood of clogging, is more difficult to clean out, takes up significantly more room on the construction site, and is not often installed by contractors.

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:

  • Please understand that we have covered the installation of solid pipe between a building and its septic tank or sewage main and that steeper slopes may be acceptable in this post. While the potential “OK” for steep drain piping may apply to steep drain piping, it does not apply in any manner to the perforated pipe laid in a septic drainfield gravel trench. Those looking for assistance on installing a septic system on a steeply sloping or rolling property should check out the following pieces:

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.

  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. [email protected] That doesn’t appear to be a concern in my opinion.
  3. @inspectapedia.com.moderator, Yes, without a doubt, that is not hygienic.
  4. [email protected], 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?

@Ted.

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.

See also:  Why Does A Septic Tank Gurgle Or Burp?

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 details to your imagination, so go ahead and get 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 about the installation of a toilet in a cabin that is approximately 300 feet from the main house, septic tank, and field.

Is too much slope a problem in this situation, given the long distance that the effluent must travel to reach the tank?

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

There should be a thorough inspection of the entire sewer line (possibly using a sewer camera), and any slope errors should be corrected.

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

  • Septic consultants, designers, and engineers
  • Septic system design alternatives-home
  • Septic system design basics-home
  • Septic system design alternatives
  • Septic system design basics
  • SEPTIC SYSTEM DESIGN BASICS
  • S

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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 Apedia.com. Alternatively, have a look at this.

INDEX to RELATED ARTICLES:ARTICLE INDEX to DRAIN SEPTIC SEWER PIPES

INSPECTION OF SEWER/SEPTIC LINES AT STEEP SITES An online encyclopedia of building and environmental inspection, testing, diagnosis, repair, and issue avoidance guidance is available at pedia.com/building. Alternatively, take a look at the following:

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Guide to Installing Septic Drainfield Piping on steep slopes

  • Send us a question or make a comment about how to construct a septic system on a steeply sloping lot.

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. Septic systems with steep slopes are known as steep slope drainfield systems. A septic drainfield or leach line is described in this article, which is applicable to tough terrain, such as steep slopes, where a property dispose of wastewater using an aseptic tank and a drainfield. We also have anARTICLE INDEX for this topic, and you can use the SEARCH BOXes at the top and bottom of the page to obtain the information you need quickly and easily.

Guide to Septic Installations on Steep Slopes or Stepped Slopes

Conflicts of interest are not tolerated at InspectAPedia.com. No affiliation exists between us and any sponsors, products, or services mentioned on this website. Septic systems with steep slopes are known as steep slope drainfields. A septic drainfield or leach line is described in this article, which is applicable to tough terrain, such as steep slopes, where a property dispose of wastewater utilizing an aerated well and a drainfield system. We also have anARTICLE INDEX for this topic, and you can use the SEARCH BOXes at the top and bottom of the page to obtain the information you need quickly and efficiently.

  • THE INSTALLATION OF Sewage OR SEPTIC LINES ON STEEP SITES is a term that refers to the installation of sewer or septic line pipes connecting a structure to its septic tank or sewer main on steep sites that slope down substantially between the structure and the septic tank. 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. Sewage pumps, sewage ejector pumps, grinder pumps, effluent pumps, sump pumps, septic pumping stations, and sewer pump alarms are examples of systems that will be required if the building or septic tank is located below the drainfield or sewer main. Installation of septic drainfields on steep or undulating terrain is described in detail in STEEP SLOPE DESIGNS(text found immediately below)

Guide to Installing Steep Slope Septic Drainfield Systems

The sketch at the top of the page illustrates one strategy for installing septic drainfields on a steep or rolling slope. Septic tank and seepage pit systems are seen in the photo above, which is placed in the flat region below the hillside and connected to a sewer line running down the steep slope. The question becomes, however, what to do when the septic effluent absorption system or soakbed itself must be placed down a steep hillside. Here are some details about the product.

  • Septic systems with a D-box for steep slopes: When septic effluent is clarified, it is discharged from the septic tank (or an effluent pumping station) and directed into a big distribution box. A larger D-box with more connection ports will be required than those used for a standard flat-area drainfield since each effluent line that will be installed across the hillside will need to be connected directly to the D-box. Separate effluent lines for steep slope septics are required: Individual septic effluent drain lines are connected to the distribution box, and each of these drain lines is directed to a separate gravel trench and perforated drainfield. Feeder pipes for effluent lines in steep slope septic systems include the following: It is not perforated, but rather solid pipe that connects the distribution box to the drainfield trench. Effluent lines for hillside or rolling land drainfields are placed along the slope, not uphill or downhill, and sloping gently (1/8″ to 1/4″ per linear foot) from the inlet end of each drainfield trench to the lowest point of the drainfield trenches.

Installing Septic Drainfield Piping on Steep Slopes Located Downhill from the Septic Tank – Rolling Land

  • For steep slope septics, flexible distribution pipe or gravelless systems are recommended: Because flexible effluent lines may be routed in a trench that must be curved in order to remain parallel to the fall line of the slope of rounded hilltops or rolling ground, flexible piping may be more convenient to construct than rigid pipe systems in areas where the land is rolling or contoured. Dosing with high pressure for steep slope septic systems: Septic effluent handling methods, such as pressure distribution systems, may be more forgiving of installation on steep or uneven sloping ground, and they may use rigid or flexible perforated pipe, depending on the application. Pressurized Septic Systems (also known as Pressure Dosing Septic Systems)
  • For septic system effluent dispersal, drip lines—which employ flexible distribution piping—might also be effective on some steep locations. Some aerobic systems that dispose of effluent using drip systems or spray systems, or that feed drip irrigation systems, can solve the problem of steep slope septic effluent disposal, according to the manufacturer. AEROBIC SEPTIC SYSTEMS, ATUs, ATUs-home Alternatively, see DESIGN AND INSTALLATION GUIDE FOR HOOT AEROBIC SYSTEMS DRIP DISPOSAL 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, which rewrites the state’s 310 CMR 15.240, 15.242, 15.247, and 15.280-15.289 regulations. Graywater disposal systems also include designs that can assist with effluent of graywater GREYWATER SYSTEMS are discussed more below.

Why Drainfield Effluent lines need to be properly sloped

Septic drainfields that use gravity to treat and dispose of cleared wastewater effluent must be correctly pitched and never slope too steeply to ensure effective operation. If this is not done, effluent will flow too fast to the low end of the drainfield line and gravel trench, where it is likely to simply break out onto the surface of the land.

If you need to build a traditional perforated pipe and gravel trench drainfield on a steep slope, you’ll need to run the trenches parallel to the fall line or down the slope itself, descending down the slope from trench to trench as you go.

Steep Slope Septic Design Research

  • Gustafson, David M., James L. Anderson, Sara F. Heger, and Barbara W. Liukkonen published a paper in which they discussed their findings. Making the decision to install an alternative septic system on a home site with a steep incline (2000). Retrieved on March 30, 2021, from the University of Minnesota Extension. the original source is:

Reader CommentsQ A

On the 25th of May in the year 2020, by (mod) – Is it possible to have the leach lines for a septic tank go uphill from the tank? Although it is possible to place the drainfield above the septic tank, an effluent pumping system will be required. This is an excerpt from the previous remark. This is where the leach line will be put, as opposed to the lower level, where the septic system is buried. When you see the house, it will be on top of this embankment, on the right side of the house, as you approach.

  • Yes.
  • Do you think there will be any issues with this setup, and how long will a pump survive for this system, given that it is not built at the same level as an ordinary septic system?
  • When installing a septic system, may the leach area be constructed on an embankment behind the home?
  • The height of the embankment is equal to the top of the roof of the single-story home that is being constructed.
  • Because the leach area is located on a steep slope away from the septic system, how often will the pump need to be rebuilt and how expensive will this procedure be in the long run of owning your property be?
  • Essentially, you must maintain a slope of 1/8 to 1/4 inch every foot of horizontal flow in order to prevent all effluent from instantly rushing to the end of the system and overloading it.
  • Steve We are therefore discharging sewage into the environment throughout the winter; I agree that diverting surface runoff away from the drainfield could be a good idea.

If none of these options work, we (and by we, I mean you) may have to resort to a raised bed or mound septic system.

The drain field is located on a level part of a hill with a width of around 60 feet.

Should a french drain be installed in the flat area uphill from a drain field in order to sort of isolate the drain field and make it more or less operate as a mound at that point in time?

Thank you, Kelly.

This will ensure that the bottom of your drain field or effluent disposal system has enough soil beneath it that the affluent does not simply hit rock and flow down The Rock and into the lake.

A septic system is being considered for installation on an island that is largely solidrock (Canadian Shield) and slopes into a body of water (Lake Superior) (5 percent to 25 percent gradient in places).

How dependable would a septic system be under these circumstances and what are the difficulties I should be aware of?

How long do you think this system will be able to work before it breaks down?

What is the highest topographic slope that may be accommodated in a septic field servicing a single family property in Frederick County, Maryland?

Thank you so much for your rapid response.

Your solution requires me to install six drop boxes across a 100-foot distance!

A sewage pipe that is excessively steep may cause water to flow too quickly, leaving particles behind.

When using a stepped line method, it is preferable to make each turn through a D box to allow for easier cleaning access.

This is my problem: I’m putting a bathroom and kitchenette in my remote 2400 square foot woodworking shop, which I’m now in the midst of constructing.

I work as a carpenter, mason, and builder.

For the pre-existing septic tank, I have around 20′ of fall and approximately 100′ of run.

The house has been put on hold (waiting for more money).

I don’t live on the construction site, and it appears that it will be several years before I can begin construction on the house.

“the sewage line down to the septic tank should be laid out in a step-wise fashion?

Besides being built on granite bedrock, the septic tank and effluent pump to a drain field are situated on the property to fulfill both perc test criteria and to maintain a minimum distance of 100 feet from a river.

When not attached directly to bedrock, frost footings must have a minimum depth of 5′ to be considered.

Another concern is the presence of black water.

See also:  Where Is The Water Level Supposed To Be In A Septic Tank? (Solution)

There will be a cleanout installed at the point where the pipe breaks through the foundation wall.

Steve, It’s amazing to read of drainfields that are more than 50 years old and are still in good working order, but I’ve seen a few myself, including a sophisticated system erected on an estate about 1920.

When a system is “functioning,” it implies that it appears to be effectively disposing of effluent – that is, there are no damp spots on the ground.

Nevertheless, in the absence of any failure data, almost no one would dig up and interfere with a drainfield.

It would be beneficial to include more specifics in this section.

Many of these were placed as long as 50 years ago and are still in good working order.

Diverse considerations, including the existence of impermeable strata, seasonal ground water, and slope stability, must be given careful attention.

This was extremely beneficial.

It was, without a doubt, expensive.

I figured I’d better include this: Because the drainfield site will be well down-slope from the construction site and tank, a gravity-fed system or a syphon system may be used.

Standard drain fields are not permitted on slopes greater than 25 percent in my county.

This is excellent information.

I have a building site that is on a 24 percent to 30 percent slope. STEEP SITE INSTALLATION OF A SEWER OR SEPTIC LINE CONTINUES READING Alternatively, choose a topic from the closely related articles listed below, or browse the entireARTICLE INDEX. Alternatively, consider the following:

Steep Slope Septic System Articles

  • SEPTIC CONSULTANTS, DESIGNERS, ENGINEERS
  • SEPTIC SYSTEM DESIGN ALTERNATIVES-home
  • SEPTIC SYSTEM DESIGN BASICS-home
  • SEWER / SEPTIC LINES at STEEP SITES
  • STEEP SLOPE SEPTIC DESIGNS
  • SEPTIC CONSULTANTS, DESIGNERS, ENGINEERS
  • SEPTIC CONSULT

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SEPTIC DESIGNS WITH A HIGH SLOPE AT INSPECTION An online encyclopedia of building environmental inspection, testing, diagnosis, repair, and issue preventive information is available at Apedia.com. Alternatively, have a look at this.

INDEX to RELATED ARTICLES:ARTICLE INDEX to SEPTIC SYSTEMS

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Is steep septic line a myth?

Author Message
HeusMember Posted: 29 Jun 2014 10:11ReplyI have been told that a septic line cannot be too steep because the fluids will pass up the solids in the line and cause the solids to plug the line. After searching the Internet, I see that many say this is a myth. Has anyone ever put in a line from house to septic tank on a steep angle? I have a septic system about 300 feet downhill from my cabin on a gradual slope. The drop is 30-40 feet I estimate. I’m tempted to put in a line going with the existing slope of the land to test this theory. I realize the proper way would be to create a series of step downs. Any thoughts on this?
NirkyMember Posted: 29 Jun 2014 13:27ReplyNo myth. You want 1/8″ drop per foot, every 8 ft = 1 inch drop. What I did is tape a 1″ cube of foam insulation onto my 8 ft level. You can also use a 8ft 2×4 and tape or nail something 1″ and then set any level on. I learned this from the septic service guy.For your steep drop, you’re going to need one or more vertical drops mixed in with the gradual 1/8″ per foot slope.
HeusMember Posted: 29 Jun 2014 14:03ReplyMy other thought was to simply build an outhouse close to the septic tank with running water.
old243Member Posted: 30 Jun 2014 21:53Replycould you not put your septic tank just outside your cabin. Not sure if the tile runs could then be steep. I would think that the tile runs would just have liquids. Someone that knows for sure could chime in. old243
JustMember Posted: 30 Jun 2014 22:15Replyif you install a sewage pump after the septic tank you can pump it any were up or down hill but your weeping bed must only have the 18 in. fall
AtlincabinMember Posted: 1 Jul 2014 00:14 – Edited by: AtlincabinReplyI’ve been reading on waste lines and the most consistent information I come up with is that they should have a minimum drop of 1/4 inch per foot up to 3 inches per foot (that is not a typo).That is for a 3″ diameter line.Larger pipes can tolerate a smaller drop per foot. YMMVGreg
BzzzzztMember Posted: 1 Jul 2014 17:00ReplyIf you install a saniflo masceration pump you can drop however much you want. robot_redir=1
NirkyMember Posted: 1 Jul 2014 18:25 – Edited by: NirkyReplyThe International Plumbing Code (2012) saysSIZE -MINIMUM SLOPE (inches)-(inch per foot) 21/2 or less-1/4 3 to 6-1/8 8 or larger-1/16 doesn’t specify what slope is optimum, just that the min is 1/8″. My septic guy says that for my 4″ pipe, 1/8″ slope is optimum, solids pretty much keep up with liquids. Works well 8 months in, no backups or cleanouts.
bldginspMember Posted: 2 Jul 2014 08:10ReplyI agree with old243 that its best to have your septic tank as close to the house, or toilets, as possible, so that solids have less distance to travel to the tank, reducing possibility of blockage. The effluent from the tank is all liquid and can travel any distance any angle to get to the drainfield.I don’t know if the ‘steeper angle causes clogs’ idea is a myth or not, but I think it’s a matter of probability- steeper would be more likely to cause a clog. With the low water use toilets they require here in Calif. it’s probably more of an issue than before.One way or the other, 300 ft from toilet to septic tank is a long way and probably more prone to clogging. In general, health depts. will allow you to have as many septic tanks as you choose all draining to the same septic drainfield, the main issue from their point of view is having a properly sized drainfield for the number of users.

Building on a sloped lot

  1. It is conceivable to construct a structure on a sloping lot, but how much more expensive is it? I own a piece of land on Lake Travis on which I’d want to build a lake cottage, but the land is on a steep incline, and I’m not sure a septic system will be feasible. What are the alternatives
  1. Two years ago, the last quote I received before scrapping my house designs increased the initial estimate of $485K to $550K for a large (5,000 sf) house from the original $485K to $550K estimate. The majority of the excess was caused by the slope of the lot
  2. I have a contractor with whom I’ve been working on several projects out here who is from from Illinois, which is known as “the land of basements.” He stated that you could either construct a complete slab or a basemented slab, with the basement option being the least expensive choice. However, he claims that is more than obvious despite the fact that I do not have any ratios or percentages. This provides you with additional storage room for all of your consumption goods (we have to protect the economy from going into a recession!). Purchase more Chinese junk!) as well as a safe haven in the event of a tornado outbreak. Then there are the advantages of resale. If anyone would want my contact information, please email me a private message or reply here. In fact, a basement would be fantastic. I have no objections to it at all
  3. There are numerous properties out here in the Lake Travis region that have a basement/understory storage space due of the slope of the property. Spetic, on the other hand, may be a greater problem. Contact Marc Pate of Pate Construction, and he will come out and determine whether or not you will have a septic problem. A walkout half-basement was included in the figures I provided above, which is a good thing considering how much work they put in on the slopes around here. Both the front half and the back half of the home would have been two floors, with the front half being three stories. There was no doubt that the property sloped sharply down from the front to the back
  4. What am I overlooking here? On a sloping land, a gravity flow septic system is more convenient. Is it possible that the water from the septic system may run into the lake too quickly? It’s possible that there are a handful of concerns with the septic system. I’m not sure whether this is true up in the mountains, but here in this section of the Edwards recharge zone, in order to build a standard septic system, you must have 3-4 feet of dirt beneath your feet. The drainfield itself is also practically level when using this sort of system, which is another advantage. Yes, the pipes leading to the field may be slanted, and in some cases, they may be required to be so, but if level land and soil are in short supply, you’ll have to explore other alternatives. Aerobic systems are the other choice that the majority of individuals in my immediate vicinity have chosen. These are the systems that are equipped with sprinkler heads that automatically drain the tank when the water level reaches a specified level. When this occurs, the water, of course, has been treated to some extent and does not smell like sewage anymore. Although these systems take up far less space, you will still need to dig a substantial hole in order to install the tank underneath. Oh, and the soil need is governed by a code or permit system, respectively. I’m not really certain of the specifics. Nevertheless, I am aware that there were a large number of septic firms operating frauds on this subject 8-10 years ago. Aerobic systems, on the other hand, are more expensive to build than traditional systems. Regular maintenance is also required for aerobic systems. I’m familiar with persons who have constructed on sloping land. Depending on the grade level, there are a variety of alternatives. Split-level houses are among my favorite architectural styles. In fact, I know of someone who had his lot milled down (not the entire lot, but a significant portion of it where the home was to be constructed) before he started construction. At first glance, it appears to be a disaster, but the home soon covers over the scar, and dirt and landscaping take care of the rest. Building on sloping lots would always be expensive, according to a carpenter friend of mine who just happened to peek at this topic. He said that it is not a building task that just anyone can do. For starters, it needs a particular design. Furthermore, it is usually necessary to hire a builder who understands “why” certain things should be constructed in a particular manner rather than simply “how.” Spend a lot of time thinking about how runoff will flow, how it will be routed, and how to maintain the drainage system once it is designed and built. If the grade isn’t too steep, milling the lot plus either a split level design or one that includes a basement would appear to be pretty good options. Ask me how I know this
  5. We have a sloping land, and there is some sort of minimum depth need for an underground septic system, although I don’t believe it is three feet. It is less than that (perhaps 18 inches if my recollection serves me well, which it most certainly does not). If it is too deep, it will not drain correctly, and if it is too shallow, it can cause health concerns. Because of the slope away from the house, each pipe is at a slightly different height, but they are all precisely 18 inches below the surface of the ground. Other criteria include the amount of pipe needed based on the number of bathrooms in the residence, the state of the soil, and the distance between the pipe and pools and neighbors. The minimum distance between the pool and the septic system is 20 feet, and the minimum distance between the pool and the appropriate lines is 15 feet. If there is an excessive amount of rock in the system, it can prevent the water from draining correctly, and instead of dissipating into the soil, the water can follow subterranean streams and other similar things
  6. Thank you. Some fantastic suggestions. I went to the Pate Construction Web site and saw some photographs of a lot that looked quite similar to mine, so I decided to purchase it. As a result, sepsis is a possibility. Unfortunately, my property is close to the water’s edge and is less than 100 feet from a cove on Lake Michigan. Regarding basements, in our previous community in Northern California, every house was a “cliff dweller,” meaning that it was built on a steep slope. The conventional strategy was to excavate a basement foundation into the slope and then construct a structure on top of that foundation. Except that in all of these houses, the basement was completely finished out, with windows and outside egress, and was therefore integrated into the overall design of the main house. Furthermore, these were substantial residences. Don’t become intoxicated and end up rolling in the lake
  7. Instead, embrace the notion and make the most of it. The house was rather simple, so you may consider erecting a barrier to avoid this from happening in the future. Stain concrete on the 1/2 basement and upper half slab, affordable hardwoods throughout, 10 foot ceilings on the main floor, 9 foot ceilings elsewhere, KitchenAid appliances, basic granite in the kitchen, shingle roof, stone exterior, vinyl windows, some crown molding, little window casing, and so on and so forth A septic field would have been “pleasant,” but not really luxurious
  8. I would have spent more time thinking about what you were going to do with the runoff than I would have spent worrying about a septic field. One item that might become a major source of concern is the amount and porosity of rock that you may come upon. I’ve tried to build a pool on hard limestone (not in Texas) and it’s been a disaster
  9. Runoff? What type of runoff do you want? From the top of the building? Is it from the septic tank? If you are unable to do septic, what other alternatives do you have? Hello there, Dogbert. My present residence is situated on a sloping terrain. In addition to overflowing gutters, the builder and previous owners failed to account for rain/snow runoff pouring down the slope toward the home – they even had one downspout that simply poured out in front of the house with nowhere else to go but under the stemwall. When building a home on a slope, it is critical to ensure proper drainage. My parents lived in a house in a gated community off of Far West Boulevard. Water would regularly overflow from a downspout, and water would seep beneath the home. Two years and $28,000.00 later, they had resolved a problem that could have been resolved for $50 in gutter maintenance. Just so you know, uncontrolled runoff may cause significant damage to a property, especially if it is on a sloping site.
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septic tank set too high

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septic tank set too high
Author:mr leak (CA)House on a slab has the septic tank drain elevation installed at wrong elevation that needs correcting. The 4 inchABS has a clean out just outside the house slab then slopes towards the 1000 gal concrete septic tank CS-2 or CS-T tank. Just before the connection the installer apparently realized that the slope was 6 inches too low to connect to the inlet as the tank was not low enoughso made up the difference with a couple of 1/16 or 1/8 bends upwards to connect the tank.How to correct. I do not think jack hammeringa new lower inlet 6 inches lower would work due to the other side discharge outlet would create a waster water head back pressure?A backflow preventer would also not work because the sewer drain would not flowBottom line is the tank is set to highAny suggestions other than a supplemental intermediate pump or resetting the tank to correct elevation?Thanks will wait for reply
Post Reply
Re: septic tank set too high
Author:hj (AZ)If you cannot regrade the pipe with 1/8″ per foot slope to raise it, then lowering the tank may be the best option, (but it will also entail lowering the seepage field). Whoever was there last, the septic tank installer or the house plumbing and sewer line installer, is the one who made the error and HE should correct it.Edited 2 times.
Post Reply
Re: septic tank set too high
Author:packy (MA)I hope this person has not been paid.
Post Reply
Re: septic tank set too high
Author:mr leak (CA)Yes paid and about 15 yeARS AGO
Post Reply
Re: septic tank set too high
Author:North Carolina Plumber (NC)I would think that a pump system would be about 10 % of the price to lower the tank and field lines.
Post Reply
Re: septic tank set too high
Author:hj (AZ)What, if anything, has changed in the past 15 years, since you should have had innumerable problems with it if it has always been that way? OR, if you have not had problems, why bother with it now?
Post Reply
  • An original estimate of $485K for a large (5,000 sf) house was pushed up to $550K by the last bid I got before scrapping my plans two years ago. It’s really because of the slope of the property
  • I’ve been working with a contractor out here who’s from from Illinois, which is known as “the land of basements,” on a few projects. He stated that you could either construct a complete slab or a basemented slab, with the basement option being the least expensive choice. However, he claims that it is more than visible despite the fact that I do not have any ratios or percentages at hand. The added room allows you to store more of your consumption goods (we have to stay out of a recession, after all!). Purchase more Chinese stuff! ), as well as a safe haven in the event of a storm or other disaster. Finally, consider the advantages of resale value. Contact information may be obtained by sending me a private message or responding to this post. To be honest, a basement would be wonderful. I have no objections to it at all
  • There are numerous properties out here in the Lake Travis region that have a basement/understory storage room due of the slope of the terrain. Spectic, on the other hand, may be a more serious problem. Contact Marc Pate of Pate Construction, and he will come out and determine whether or not you will have a septic issue. A walkout half-basement was included in the prices I listed above, which is a good thing considering how much work they do on slopes. The front part of the home would have been two stories tall, while the back half would have been three stories tall. There was no doubt that the property sloped sharply down from the front to the rear
  • What am I overlooking? On a sloping land, installing a gravity flow septic system is simpler. Are there concerns that the sewage will enter the lake at an excessively rapid rate? A handful of faults with the septic system may exist, it appears. I’m not sure whether this is true up in the mountains, but here in this section of the Edwards recharge zone, in order to build a standard septic system, you must have 3-4 feet of dirt under your feet. The drainfield itself is also virtually level when using this sort of arrangement. It is true that the pipes leading to the field may be slanted, and in certain cases they may be required to be sloped, but if flat terrain and soil are in short supply, you may need to explore alternative solutions. In addition to aerobic systems, the majority of others in my immediate vicinity have chosen this choice as well. Those are the systems equipped with sprinkler heads that, when water levels reach a specific point, automatically shut off the water supply. When this occurs, the water, of course, has been treated to some extent and does not smell like sewage. Despite the fact that these systems take up far less space, you will still need to dig a substantial hole in order to install the tank underneath. Not to mention that the soil requirement is under the purview of code or permit regulations. There are several details that I’m not quite certain about at this point. Eight to ten years ago, I am aware that there were several scammers preying on unsuspecting customers in this industry. When compared to aerobic systems, traditional systems require less installation time and money. Aside from that, aerobic systems require routine maintenance as well. Building on a sloping property is something I’m familiar with. Based on the grade, there are a variety of alternatives. Split-level residences are among my favorite types of housing. In fact, I know of someone who had his lot milled down (not the entire lot, but a significant portion of it where the home was to be constructed) before he began construction. After a while, the scar is covered over by the home, and dirt and landscaping cover up the remainder of the scar. Building on sloping lots would always be expensive, according to a carpenter friend of mine who just happened to check at this topic. He said that it is not a building task that everyone can accomplish. Among other things, it need custom design. It is also usually necessary to choose a builder who understands “why” certain things should be constructed in a particular manner, as opposed to only “how.” Spend a lot of time thinking about how runoff will flow, how it will be routed, and how to maintain the drainage system once it is designed and built. If the gradient isn’t too steep, milling the lot and either a split level design or one that includes a basement would appear to be relatively decent possibilities
  • Ask me how I know this
  • We have a sloping lot, and there is some sort of minimum depth need for the septic system
  • Nevertheless, I don’t believe it is three feet. It is less than that (perhaps 18 inches if my recollection serves me well, which it most certainly does not) You might have health concerns if your hole is too deep since it will not drain correctly. Because of the slope away from the house, each pipe is at a slightly different height, but they are all exactly 18 inches below the surface of the earth. Additionally, the amount of pipe needed is determined by the number of bathrooms in the residence, the soil’s quality, and the distance between the pipe and pools or neighbors. The distance between the pool and the septic system must be 20 feet, and the distance between the pool and the necessary lines must be 15 feet. If there is an excessive amount of rock in the system, it can prevent the water from draining correctly, and instead of dissipating into the soil, the water can follow subterranean streams and other similar things
  • Thank you. Some really good tips here! The Pate Construction Web site had some photographs of a lot that looked quite similar to mine, so I went there to get some inspiration. Septic tank treatment may thus be an option. Unfortunately, my property sits close to the water’s edge and is less than 100 feet from a cove in the lake. When it came to basements, every house was a “cliff dweller” in our previous community in Northern California, because it was built on a steep slope. The traditional strategy was to carve a basement foundation into the slope and then construct a structure on top of it. Aside from the fact that the basements in all of these homes were completely finished out, with windows and outside egress, they were considered to be a part of the overall main house design. Also noteworthy was the fact that they were substantial residences. Don’t become intoxicated and end up rolling in the lake
  • Instead, embrace the notion and make the most of it! If you have a simple house like this, you might want to set up a barrier to keep this from happening. Stain concrete on the 1/2 basement and upper half slab, affordable hardwoods throughout, 10 foot ceilings on the main floor, 9 foot ceilings elsewhere, KitchenAid appliances, basic granite in the kitchen, shingle roof, stone exterior, vinyl windows, some crown molding, little window casing, and so on and so forth. A septic field would have been “pleasant,” but not very luxurious
  • I would have spent more time wondering about what you were going to do with the runoff than I would have spent worrying about the septic field. When it comes to rock, the amount and porosity of rock that you may encounter might be a significant source of concern. In the past, I’ve attempted to construct a pool out of hard limestone (not in Texas), and the results have been disastrous. Runoff? What type of runoff are we talking about here? How about from the top of the building’s roof? How did you get here? What choices do you have if you are unable to do septic? Hi Dogbert. How are you doing today? My current residence is situated on a sloping terrain. In addition to overflowing gutters, the builder and previous owners failed to account for rain/snow runoff pouring down the hill toward the home – they even had one downspout that just poured out in front of the house, with nowhere else to go but under the stemwall – thus flooding the basement. Any home constructed on a slope must have adequate drainage. In a gated community off of Far West, my parents had a house. When the downspout overflowed, water would seep inside the home and cause it to flood. They spent $28,000.00 to resolve a problem that could have been resolved for $50 by installing gutters. Putting it bluntly: if you live on a sloping property and allow runoff to accumulate, it may do significant harm.
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Can a drain pipe have too much slope?

Drain pipe slope should be 1/4″ per foot, which is also the minimum required by regulation for pipes with a diameter of less than 2-1/2 inches. This inclination allows the water to go slowly enough to float the solids along with it, while yet moving quickly enough to scour the pipes’ interior walls. Drain pipes and sewage lines that are sloped too steeply (1/2 inch per foot or more) are just as prone to clog as pipes that are inclined too slowly (1/2 inch per foot or less). This is because the liquids go too quickly and the solids are left behind.

Plumber James Freeman of J.W.

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