How Much Soil Is Needed Over Septic Tank? (TOP 5 Tips)

the depth of soil backfill over the septic tank lid or septic tank riser lid, ranging from 0″ (which means you should see it) to just a few inches (which means grass may be dead in this area) to 6-12″ or even more.

  • A typical septic drainfield trench is 18 to 30 inches in depth, with a maximum soil cover over the disposal field of 36″; or per the USDA, 2 feet to 5 feet in depth.

How much dirt should be on top of a septic tank?

Each layer should be uniform, no greater than 24 inches thick, and of nearly equal heights around the perimeter of the tank. However, compaction under the haunch (bottom curvature of some tanks) is best done in 6- to 12-inch layers.

How much dirt should be on top of a drain field?

Septic systems are generally planned to have anywhere from 6 inches to 30 inches of soil on top of them.

Should a septic tank lid be covered with dirt?

The lid covers should fit tightly — if they don’t, a company that specializes in septic repairs should be called to fix them. A septic tank stores the solids from drains and needs to be pumped out about every two years, so it’s not a good idea to cover the area — you need to always be sure where to find the tank.

Can I add dirt on top of septic field?

After the installation of a new septic system, you may see some settling of the soil around and over the tank and lines leading to the drain field. Do not add additional soil, as it will interfere with the evaporation of excess water from the field.

How many lids are on a septic tank?

In order to make repairs or perform regular maintenance or cleaning/pumping of the tank, access must be provided. There are usually two lids located at the top of the septic tank-one located over the inlet “T” and one located over the outlet “T” (see “Septic Components: Septic Tanks”).

How deep are septic tank lids?

Often, septic tank lids are at ground level. In most cases, they have buried anywhere from four inches to four feet underground.

Can you plant a garden on top of a septic field?

The most important reason you should not install a vegetable garden on top of, or right next to, a septic system disposal field is because the plants can become contaminated by wastewater that has not yet been renovated by the field. Plants on disposal fields can absorb wastewater pathogens.

What can you put on top of a septic field?

Put plastic sheets, bark, gravel or other fill over the drainfield. Reshape or fill the ground surface over the drainfield and reserve area. However, just adding topsoil is generally OK if it isn’t more than a couple of inches. Make ponds on or near the septic system and the reserve area.

Why is the ground soft around my septic tank?

The presence of healthy, lushly growing plants around your septic tank or along the route of your drainage lines indicates wet areas, as does a spongy or damp feel to the ground. Excess moisture might mean that your tank is full or that your drainage pipes are damaged.

Do septic tanks need to be airtight?

Septic tanks need to be watertight. The riser should be sealed to the top of the tank and the riser cover should be sealed to the riser with butyl rubber or some other flexible sealant. No liquid should enter or leave the tank.

How do I hide my above ground septic tank?

The Do’s For Hiding Your Septic Tank

  1. Plant tall native grasses with fibrous roots around the opening to conceal the tank lid from view.
  2. Place a light statue, bird bath or potted plant over the septic lid.
  3. Septic tank risers and covers are an alternative to concrete and blend into green grass.

Should I install a riser on my septic tank?

Having a riser in place can also significantly reduce the cost of septic tank maintenance over time through the ease of access and time on the job saved. Plus you will be spared digging up your lawn every time as well.

Can you put anything over a septic field?

To maintain the integrity and longevity of your drainfield, you should never put anything heavy on top of any part of it. You shouldn’t even drive over the drainfield, as the vehicle can crush the drainfield lines. Heavy items cause soil compaction.

Can you put a greenhouse over a septic field?

A greenhouse can be erected on a septic field to grow certain types of plants. The greenhouse should not have permanent foundations, which could easily damage the septic system. Do not plant directly into the ground over a septic field, as the plants could absorb contaminants released by the system.

Why is grass green over septic tank?

Greener grass over the septic tank may be the result of someone seeding that area if the tank cover was excavated for service. A backing up pipe to leachfield (or worse, a failing leachfield) could cause effluent to drain too slowly out of the septic tank or back up even into the building.

Soil Evaluation for Home Septic Systems

The first stage in the construction of a septic system is to analyze and define the soil conditions on the site. The soil in a septic system is the most significant component since it is an excellent substrate for wastewater treatment. The system designer utilizes information about the soil to determine the type and size of the system to be installed.

Role of Soil in Wastewater Renovation

The septic tank is responsible for removing bigger particles and fats from wastewater in a septic system. A variety of pollutants are still present in the wastewater that runs out of the septic tank, and these contaminants must be eliminated before the water may be safely released into surface or groundwater. The wastewater from a septic tank includes bacteria that can cause illness in humans. In addition to producing unpleasant odors, organic matter in effluent and nutrients in wastewater (nitrogen and phosphorus) can have a negative influence on aquatic life.

Soil Depth

The sort of treatment system that may be employed on a property is determined by the depth of the soil. Soil treatment systems are best suited for the deepest soils—those that are more than 3 feet deep to a limiting layer (also called leach field systems). Because the majority of Ohio’s soils (84 percent) are shallower than 3 feet in depth, the designer must take soil depth into consideration while selecting the most effective treatment technique (Figure 1). Generally speaking, a limiting layer is a zone in the soil profile that is ineffective in treating wastewater.

In addition, the depth at which the soil is saturated with water for many weeks each year is considered a limiting layer in soil erosion.

  • Bedrock that has been fractured
  • Sand and gravel layers
  • Bedrock that is hard and solid
  • Glacial till that is dense and compacted
  • Pans with a lot of density or layers of cement, such as fragipans Water tables are defined as zones of seasonal, perched, or long-term saturation.

Soil Permeability

Permeability is a term used to describe the ability of soil to transfer water through it. Permeability is calculated based on the texture and structure of the soil. The relative amounts of sand, silt, and clay in a soil’s texture are referred to as its texture. Sandy soils have a gritty feel to them and can allow air and water to circulate quickly through the ground. Clay soils are sticky and extremely thick, making it difficult for air and water to move freely through them. Loamy soils, which are combinations of sand, silt, and clays, are the best soils for wastewater treatment since they are well adapted for this purpose.

The soil particles bind together to create structural units as a result of their adhesion.

The soil’s structure generates routes in the soil profile that allow for the circulation of air and water through the soil profile (Figure 2). The structure of the soil changes as it is dug deeper. Surface layers may be granular, whilst underneath layers may be blocky or enormous in appearance.

Soil Saturation

When the soil is saturated with water, it is unable to take wastewater and remove toxins from the environment. If surface and groundwater are contaminated by bacteria that might cause illness, the water that drains away will carry these contaminants with it. Even if the job is being carried out during a particularly dry time of year, a soil assessor must search for evidence of saturation in the soil. The hue of the soil is used to show that the soil has been moist for a period of several weeks each year.

The minerals that give the soil its brown hue can also breakdown and wash away when exposed to high water pressure, leaving behind gray-colored residues.

Soil and Site Evaluation

Soil scientists are educated in the description and mapping of soils. Hire a soil scientist to collect the information on soil depth, permeability, and saturation that will be needed to select and build a wastewater treatment system for their property. A few hundred dollars may be charged for this service, depending on the amount of time it takes to review the site. The Association of Ohio Pedologists maintains a list of soil scientists who are available for consultation. The list may be found at

How much dirt goes in a septic field?

Asked in the following category: General The most recent update was made on February 28th, 2020. Septic drain fields (also known as aleach fields) are made up of a network of perforated pipes that are sunk in trenches and filled with aggregates (12- to 212-inch gravel or 12-4-inch rubber chips), soil, and other materials. These drainlines are normally 18 to 36 inches wide and 6 inches deep, with a minimum depth of 6 inches. the level of soil backfill over the septic tank lid or septic tankriser lid, which can range from 0″ (which indicates that you should be able to see it) to a few inches (which indicates that the grass in this region may be dead) to 6-12″ or even more.

  • In a normal septic drainfield trench, the depth ranges from 18 to 30 inches, with a maximum soil cover over the disposalfield of 36 inches “Alternatively, according to the USDA, 2 feet to 5 feet in depth.
  • Furthermore, is it permissible to place soil over my drain field?
  • When it comes to coverage, drain fields are typically built to function with 18 to 24 inches of coverage, unless they have been developed to cope with certain soil types.
  • To be more specific, the following is how a standard conventionalsepticsystem operates: All of the water that leaves your home drains through a single main drainage line into an aseptic tank.

The liquid wastewater (effluent) is subsequently discharged from the tank into the drainfield. It is a shallow, covered hole dug in unsaturated soil that is used as a drainage field.

Proper Backfill for Septic Tanks

Receive articles, stories, and videos about septic tanks delivered directly to your email! Now is the time to sign up. Septic Tanks and More Receive Notifications After a septic tank has been installed, it must be backfilled in the proper manner. Backfilling all tanks with successively tamped “lifts” or depth increments of consistent gradation should be the standard procedure. The installer should ensure that the backfill material is devoid of clods, big boulders, frozen stuff, and debris, all of which can cause voids in the backfill material, which may enable the foundation to settle over time.

  1. Each layer should be homogeneous in thickness, no more than 24 inches thick, and of roughly identical heights around the perimeter of the tank, with the exception of the top layer.
  2. If the material being used is compactable, it should be compacted in order to prevent the earth surrounding the tank from sinking.
  3. Backfill the tank with granular material until it reaches at least the midseam of the tank to ensure that settling is kept to a minimum.
  4. Fill around a septic tank that has been compacted All pipe penetrations through all tanks must remain waterproof after the tanks have been refilled with water.
  5. In order to provide a stable foundation for the pipe, the backfilled earth should be tapped.
  6. Pipe joints should be laid atop native soil rather than in the excavation to avoid the risk of their settling in the future.
  7. It is possible to sleeve pipes that may run over the top of the tank or through excavated portions (such as electrical conduit and/or return lines) to give additional support.

It is possible that the manufacturer of a nonconcrete tank will recommend or require that the tank be simultaneously filled with water to just above the backfill level in order to avoid uneven or excessive pressure on the tank walls during the installation process and to reduce the risk of the tank shifting position during installation.

It may be required to use a tamping tool to ensure that backfill makes adequate contact with and between tank ribs, but care must be given to prevent harming the tank during the process.

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She has a master’s degree in civil engineering and a doctorate in environmental engineering.

Her responsibilities include serving as the education chair for the Minnesota Onsite Wastewater Association and the National Onsite Wastewater Recycling Association, as well as serving on the National Science Foundation’s International Committee on Wastewater Treatment Systems.

Send an email to [email protected] if you have any concerns concerning septic system care and operation. Heger will respond as soon as possible.

Drainfield Size & Design

  • The percolation rate of a soil is an essential soil feature that measures how long it takes water to descend one inch in a saturated hole drilled in the ground.
  • In sandy soil, 1 inch can be achieved in 3 minutes
  • In clay soil, 1 inch may be achieved in 48 minutes.
  • If it takes less than 5 minutes for water to drop 1 inch in a saturated hole, the effluent will flow too quickly for it to be adequately treated, as is the case with sandy soil. If it takes more than 60 minutes for the water to drop one inch, the effluent will not be able to travel as quickly as it should, and effluent may rise to the top of the water table. This is something that may happen in clay soil.

Drainfield Size

  • According to the number of bedrooms and soil qualities, the drainfield is measured in square feet, and its size is reported in square feet. It has been determined by the Nebraska Department of Environmental Quality (NDEQ) how many square feet of drainfield trench will be required. Title 124 of the North Dakota Department of Environmental Quality (NDEQ) contains the design, operation, and maintenance requirements for on-site wastewater treatment systems
  • The table below is an excerpt from that title. A three-bedroom house with a mid-range percolation rate of 25 minutes per inch, for example, requires a minimum of 750 square feet of space to function properly.

Square Feet of Drain Field Trench Required for Single Family Dwelling

Number of Bedrooms 1 2 3 4 5 6 7 8 9
Perc Rate in Minutes Per Inch 200 gpd 300 gpd 400 gpd 500 gpd 600 gpd 700 gpd 800 gpd 900 gpd 1000 gpd

5Systems must be constructed with a 12 inch loamy sand liner that has a percolation rate of 15 to 20 minutes per inch and should be developed at a percolation rate of 11-20 minutes per inch, with a percolation rate of 15 to 20 minutes per inch.

5-10 165 330 495 660 825 990 1155 1320 1485
11-20 210 420 630 840 1050 1260 1470 1680 1890
21-30 250 500 750 1000 1250 1500 1750 2000 2250
31-40 275 550 825 1100 1375 1650 1925 2200 2475
41-50 330 660 990 1320 1650 1980 2310 2640 2970
51-60 350 700 1050 1400 1750 2100 2450 2800 3150

60Systems must be developed by a licensed professional engineer or architect. A building permit is required. 017.02 In order to determine the needed square footage for enterprises, the following equation should be used: The daily design flow divided by the number of hours in the day (Five divided by the square root of the percolation rate). 017.03 In order to calculate the absorption area for a bed, first determine the needed square footage for a trench and then multiply the required square footage by the factor from Table 14.2.

How Your Septic System Works

Underground wastewater treatment facilities, known as septic systems, are often employed in rural regions where there are no centralized sewage lines. They clean wastewater from residential plumbing, such as that produced by bathrooms, kitchen drains, and laundry, by combining natural processes with well-established technology. A conventional septic system is comprised of two components: a septic tank and a drainfield, often known as a soil absorption field. It is the septic tank’s job to decompose organic matter and to remove floatable stuff (such as oils and grease) and solids from wastewater.

Alternate treatment systems rely on pumps or gravity to assist septic tank effluent in trickling through a variety of media such as sand, organic matter (e.g., peat and sawdust), constructed wetlands, or other media to remove or neutralize pollutants such as pathogens that cause disease, nitrogen, phosphorus, and other contaminants.

Specifically, this is how a typical conventional septic system works:

  1. All of the water that leaves your home drains down a single main drainage pipe and into a septic tank. An underground, water-tight container, often composed of concrete, fiberglass, or polyethylene, serves as a septic system’s holding tank. Its function is to retain wastewater for a long enough period of time to allow particles to sink to the bottom and form sludge, while oil and grease float to the surface and produce scum. Sludge and scum are prevented from exiting the tank and moving into the drainfield region by compartments and a T-shaped outlet. After that, the liquid wastewater (effluent) exits the tank and flows into the drainfield. The drainfield is a shallow, covered hole dug in unsaturated soil that serves as a drainage system. Porous surfaces are used to release pretreated wastewater because they allow the wastewater to pass through the soil and into the groundwater. In the process of percolating through the soil, wastewater is accepted, treated, and dispersed by the soil, finally discharging into groundwater. Finally, if the drainfield becomes overburdened with too much liquid, it can flood, causing sewage to flow to the ground surface or resulting in toilet backups and sink backups. Finally, wastewater percolates into the soil, where it is naturally removed of harmful coliform bacteria, viruses, and nutrients. Coliform bacteria are a kind of bacteria that may be found in the intestines of humans and other warm-blooded animals, with humans being the most common host. As a result of human fecal contamination, it is a sign of this.

The Guadalupe-Blanco River Authority has built an animated, interactive model of how a residential septic system works, which you can view here.

Do you have a septic system?

It’s possible that you’re already aware that you have a septic system. If you are not sure, here are some tell-tale symptoms that you most likely are:

  • If you have a septic system, you may already be aware of this fact. Here are some tell-tale indicators that you most likely do, if you don’t already know:

How to find your septic system

You can locate your septic system once you have confirmed that you have one by following these steps:

  • Taking a look at the “as constructed” drawing of your house
  • Making a visual inspection of your yard for lids and manhole covers
  • Getting in touch with a septic system service provider for assistance in locating it

Failure symptoms: Mind the signs!

A bad odor is not necessarily the first indicator of a septic system that is failing to work properly. Any of the following signs should prompt you to seek expert assistance:

  • Water backing up into the drains of homes and businesses
  • It is especially noticeable in dry weather that the drainfield grass is bright green and spongy. The presence of standing water or muddy soil near your septic system or in your basement
  • A strong stench emanating from the area surrounding the septic tank and drainfield

Soils types and their impact on septic systems

Even if your septic system is in excellent condition, it is dependent on the correct type of soil to finish the process of purifying the wastewater from your home. Depending on the soil type in the drainfield region, how well the effluent is filtered and whether or not the water that is returned to the water cycle is good enough will be determined. As a result, while installing a septic system, it is critical to have a thorough grasp of the soil makeup. Soil is composed of a variety of layers that are divided into four major categories: surface soil, subsurface soil, subsoil, and substratum.

Surface soil– also known as topsoil, this type of soil is generally black in color due to the high concentration of organic materials present due to the decaying organisms.

Typically, this is where the drain field is located.

Subsoil is the layer of soil that lies beneath the subsurface soil and is composed of a mixture of small particles of clay, silt, and sand, but it contains less organic matter than the surface soil.

Subsurface soil is composed of small particles of clay, silt, and sand, but it contains more organic matter than the surface soil. Due to its composition of either unconsolidated sediment or bedrock, the substratum is sometimes referred to as a non-soil layer.

Morphological characteristics of soil

The morphology of the soil determines the type of septic system that will be installed as well as the effectiveness of the system once it is installed. When designing a septic system, there are five important soil morphology characteristics that must be taken into consideration. These are the ones:

Soil texture

The relative proportions of the various soil particles in the soil are referred to as the texture of the soil. The texture of the soil can have a negative impact on a soil’s capacity to process and safely dispose of wastewater, according to the Environmental Protection Agency. The porosity, hydraulic conductivity, and structure of the soil are all influenced by the texture of the soil. Soils with a heavy texture, such as clay soils, have poor drainage characteristics. As a result, water does not pass through them quickly enough to dispose of the necessary amount of wastewater.

When it comes to septic system design, soils are divided into four major groups based on the texture of the soil.

  • Sandy textured soils are classified into four groups: Group I
  • Group II
  • Coarse Loamy Textured Soils
  • Group III
  • Fine Loamy Textured Soils
  • And Group IV
  • Clayey Textured Soils.

Soils in Group I and Group II are the most suitable for use with traditional septic systems. Group III and Group IV soil textures may need the construction of more sophisticated sewage treatment systems.

Soil structure

Soil structure is concerned with how individual soil particles are grouped together to produce bigger groupings of particles, which are referred to as aggregates in the scientific community. As a result of its structure, soil has an influence on water percolation, the capacity of soil to handle wastewater, and the quantity of air that may be introduced into the soil. There are five distinct approaches to characterize soil structure, which are as follows:

  • Absence of structure (e.g. single grain or massive)
  • Crumb and granular
  • Block-like
  • Platy
  • Prismatic
  • Absence of structure (e.g. single grain or massive)

Septic systems benefit from granular soil structure because it increases soil separation and internal drainage, which is perfect for septic systems. On the other hand, soil types with a platy, prismatic, or massive structure are not recommended for use with traditional septic systems. The huge and platy structures hinder aeration as well as internal drainage, whereas prismatic structures allow untreated wastewater to flow directly into the water table without being treated first.

Clay mineralogy

Clay mineralogy is concerned with the quantity of clay present in a soil, and this will have an impact on the percolation rate of the soil as a result. Generally speaking, there are two sorts of clays: 2:1 and 1:1. A 2:1 clay is one that expands significantly when wet, whereas a 1:1 clay just barely expands when wet. Clays with a 2:1 mineralogy (for example, montmorillonite) shrink when they are dry and expand when they are wet, as seen in the diagram. As the soil swells, the particles of the soil expand into the structural spaces, reducing the porosity of the soil in the process.

Consequently, soils with a 2:1 clay mineralogy are ineligible for the installation of traditional septic tanks.

That a result, they do not limit the flow of water to the same extent as their 2:1 counterparts do. They are capable of assisting with the installation of septic systems.

Soil consistency

The consistency of a soil is assessed by testing how well a certain soil can adhere to other things or how well it can form forms when pressed between two surfaces. When the soil is dry, damp, or even wet, it is possible to identify the consistency of the soil. Firmness, friability, and looseness are the characteristics that influence the consistency of most soils. It is possible that the soil may be particularly solid when wet, indicating that it contains expansive mineralogy, and it will be rated as unsuitable for septic systems.

It is possible to determine how effectively dirt adheres to other things by pushing the soil between two fingers: the thumb and forefinger.

To determine the flexibility of the soil, roll a small amount of it between your thumb and forefinger.

Organic soils

Organic soils are defined as soils that contain 20 percent or more organic matter to a depth of at least 18 inches and are rich in organic matter. If your soil falls within this category, you should avoid installing septic systems. Organic soils, on the other hand, tend to remain moist throughout the year because they drain too slowly. Organic soils are particularly susceptible to subsidence, which can cause damage to the septic system.

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Soil wetness

Wastewater treatment cannot take place adequately in soils that are not sufficiently aerated. As soon as soils become saturated with water, the spaces are filled with water, leaving little or no space for air to circulate. Because moist soils lack adequate air circulation, they are unable to maintain a septic system. The color of the soil may be used to determine the amount of moisture in the soil. The term “chroma” refers to the relative purity, strength, and saturation of a soil’s color in terms of its color.

For example, moist soils have a chroma value of two.

When the water table is high during a certain season, the soil may become wetter than usual at regular times.

Constituents of wastewater and how they react with various soil types

Various elements of wastewater can have varied effects on the soil depending on their concentration. Check out the following examples of wastewater ingredients to see how they could react in different soils.

Organic substances

BOD (Biological Oxygen Demand), Total Suspended Solids (TSS), and Chemical Oxygen Demand (COD) are all metrics used to assess the concentrations of synthetic and natural organic chemicals in wastewater (COD). Ideal conditions exist when a well designed and maintained septic system can remove the majority of these components through the liquefaction process initiated by the bacteria. The leach field, on the other hand, continues to receive certain organic compounds that have gone through the septic tank.

Organic compounds are removed from the soil via a variety of processes, including filtering and decomposition, that occur naturally.

The bacteria in the effluent store polysaccharides in the form of slime capsules, which coat the soil particles and reduce the soil’s ability to percolate water through the soil.

When building a septic system, it is important to consider adequate size in order to avoid an excess of effluent in the leach field, which might worsen the biomat problem.


BOD (Biological Oxygen Demand), Total Suspended Solids (TSS), and Chemical Oxygen Demand (COD) are three metrics used to assess the concentrations of synthetic and natural organic compounds in wastewater (COD). Ideal conditions exist when a well designed and maintained septic system can remove the majority of these components through the liquefaction process initiated by bacteria. The leach field, on the other hand, continues to receive certain organic chemicals that have gone through the septic system.

Through a variety of processes, such as filtering and breakdown, the soil eliminates organic contaminants.

The bacteria in the effluent store polysaccharides in the form of slime capsules, which coat the soil particles and reduce the soil’s ability to percolate water.

When building a septic system, it is important to consider adequate size in order to avoid an excess of effluent in the leach field, which might worsen the biomat problem in the future.


When it comes to phosphorus in septic tank effluent, there are two primary sources: washing detergents and human feces. Fortunately, anaerobic bacteria are capable of turning the majority of this phosphorus into soluble orthophosphates. To the contrary of nitrogen compounds, soluble phosphates react with diverse soil types and result in the removal of phosphate ions through numerous processes such as soil-plant interaction, plant uptake, precipitation, and biological immobilization (bio-immobilization).

Détergent surfactants

Surfactants, in general, can have an impact on the water retention and water transportation characteristics of soil. When the surfactant concentrations in the septic system exceed 30 mg/l, they have the potential to limit the hydraulic conductivity of the soil, which means that the wastewater will not be able to pass freely through the soil. The overall consequence will be that the water levels in the septic tank will increase over what is considered to be optimal. As a result of adsorption, anionic surfactants begin to build in the soil as detergent surfactants are removed from the environment.

This may be accomplished with relative ease by refraining from the use of detergents that include surfactants.

Toxic organic compounds

Toxic organic substances like as trichloroethylene (TCE), chlorinated hydrocarbons (MC), methyl chloroform, and others are widely found in chemical septic additives and cleansers. Trichloroethylene (TCE), chlorinated hydrocarbons (MC), methyl chloroform, and others are toxic organic compounds. If they reach the saturated zone, MC and TCE will sink to the bottom of the water phase, since they are denser than water and will sink to the bottom of the water phase. Several of these organic molecules remain in the sludge as a result of their inability to decompose, while others end up in the drain field and end up poisoning groundwater.

As a result, owners of septic systems should avoid the use of these compounds altogether. Biological additives, such as those manufactured from bacteria and enzymes and sold by Bio-Sol, are recommended for cleaning septic systems.


As single-celled creatures, bacteria are frequently found stuck in the pore spaces of soil particles, where they can cause significant damage. This is, in fact, an essential process since it aids in the removal of enteric bacteria from the effluent in the leach field, which is beneficial for the environment. This process also leads in the development of biomat, which aids in the entrapment of bacteria in the system. The attenuation of bacteria contributes to the prevention of groundwater contamination with disease-causing germs.

Furthermore, the attenuation of bacteria is controlled by the amount of bacteria present in the effluent, soil texture, loading rate, kind of bacteria present, soil moisture, and temperature.


Viruses are not only smaller in size than bacteria, but they also function in a distinct manner in the environment. Natural die-off and enzyme assault are among the methods used to inactivate or remove viruses from the soil. Precipitation, adsorption, filtration, and natural die-off are among those employed. In fact, many of the same variables that influence the adsorption of bacteria by soil also influence the adsorption of viruses by the soil. There are several critical soil factors that influence viral adsorption.

How the soil type and its percolation impacts the performance of the septic system

The behavior of effluent is influenced not only by the element in question, but also by the state and composition of the soil underneath it. The degree of wetness is governed by a number of factors, one of which is the distance between the surface and the water table. Depending on rainfall patterns and human activities such as irrigation and stormwater management, the depth of the water table can change significantly. When building a septic system, it is critical to consider how much vertical separation there should be between the water table and the bottom of the drain field.

  • It is more difficult for water to move through unsaturated soil than it is for water to go through more saturated soil in the same area.
  • When building a septic system, it is vital to consider the depth of the water table during the rainy season, which is measured in feet.
  • When the wet season arrives, soils with impermeable horizons are more likely to create perched water levels.
  • In the course of the site research, it is critical to take note of several significant soil features such as the texture of the soil, the presence or absence of cemented layers, the degree of aggregation of soil particles, and the level of the water table during the rainy seasons.
  • For example, it may be necessary to create alternative systems such as mounds in order to increase the distance between the rainy season water table and the bottom of the system during the dry season.

The same procedure may be required in the case of cemented soil, clay soil, or in the case of any other unacceptable conditions that may be discovered during the site assessment.


There are some soils that are not suited for typical septic systems, and installing septic systems on these soils without taking the proper precautions can result in a variety of problems, including water pollution. Clay soil is extremely compact and does not allow for the passage of wastewater through it to occur. As a result, clay soils have the potential to cause blockages in the leach field. The optimal soil for a septic system is one that is somewhere in the middle of the spectrum between gravel and clay.

This soil offers the ideal characteristics for filtering wastewater while yet enabling it to soak through and into the surrounding environment.

Best Soils for Septic Systems and Drain Fields

Best Soils for Septic Systems and Drain Fields – How to Choose the Right Soil

Best Soils for Septic Systems and Drain Fields

What do germs, dirt, and gravity all have in common? Read on to find out. All of these environmental elements and natural processes contribute to the ability of your septic system to perform its waste processing and wastewater treatment functions. Untreated water that is discharged back into the water table can pollute your town if these measures are not taken. While we understand how to maintain the health of the bacteria in our septic tanks, and while gravity works on its own, what about our soil?

Soil Requirements

Other rules, including as setbacks, tank capacity, and lawn size, are all important considerations. Soil requirements and soil types may make or break your septic system installation. Not only that, but there are a number of elements that must be considered when determining if the soil in your yard is suitable for a septic system and drainfield.


Natural processes such as wetting and drying, freezing and thawing, and freezing and thawing alter the soil structure throughout time. Pores and gaps are created in the various strata of the earth as a result of these activities. Pores allow for the free flow of water and air downward without being obstructed by other materials. Septic-system-ready soil should contain a significant number of pores and spaces that are linked, if at all possible (not lone pockets).


Are there any coarse or gritty soils present? Will the soils be able to absorb an excessive amount of water? Is it hefty or light in weight? The amount of sand, silt, and clay contained in the soil is determined by the texture of the soil. A high concentration of clay indicates that the soils are overly heavy. A ground that has too many heavy silts will be less permeable.


In the absence of an exact definition or categorization, drainage refers to a soil’s natural capacity to drain water away from a specific location. For testing, check the soil moisture levels before doing any land alterations on a regular day (do not check the soil moisture levels the day after a hurricane or major storm passes by).

Is there a quick and easy technique to categorize poorly draining soil? The soil in your yard is generally not the ideal for septic systems if there are regular depressions or puddling in your yard.


Slope angle is not directly connected to soil quality, but a steep slope will deny even the greatest soil the opportunity to percolate and treat wastewater before it enters the groundwater system.

How Do You Test Soil for Septic Systems?

Percolation tests, often known as deep hole tests, are performed. Deep Hole Tests are exactly what they sound like: tests that are conducted via a hole that has been drilled deeply. For the most part, the holes are around seven to ten feet deep and are located below the bottom of probable drainfield locations. Testers take soil samples and measure the height of the seasonal high water table in proportion to the depth of the soil above it, which they then analyze. Percolation testing necessitates the drilling of two or more holes, each of which is generally half a foot to a foot deep — the depth of an ordinary leach field — to determine the depth of the soil.

Even from one county to another and from one municipality to another, percolation needs differ.

Best Soils for Septic Systems and Drainfields

Most yards and landscapes are composed of a variety of soil types, thus examining soil features and clay levels is more beneficial than identifying specific types of soil. The following are the ideal soils and soil types for drain fields:

  • Sandy soils
  • Soils with a low percentage of clay content
  • Loamy Soils (soils that include a variety of particle sizes that allow for gaps and pores to develop)
  • Soils that are either non-retentive or non-absorbent. Landscaping materials such as clay and silt rapidly absorb water, taking up additional area and clogging the system.

What is the optimal soil? Somewhere in the middle between gravel and clay.

Best Soils for Septic Systems Video

Are you concerned that your soil will not be able to support septic systems and drainfields? Contact Advanced Septic Systems now to discuss your alternatives and the systems that will function best in your yard and environment.

See also:  Why Is My Septic Tank Full In 2 Years? (Solution found)

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septic system — Butte County Septic — Magneson Tractor Service Inc.

Welcome to the World Wide Web! This is the location where messages propagate rapidly, regardless of their legitimacy. However, this was occurring long before the advent of the internet, through the basic medium of word of mouth. With the abundance of information available and flowing, it can be difficult to discern between realities and urban legends. We’ve chosen to put the record straight on a few common misconceptions concerning septic tanks and systems in order to help others from making the same mistakes.

Starting With a New Septic Systems Requires Seeding

What exactly is seeding? It does exactly what it says on the tin: it assists your system and bacteria in growing by providing “seeds,” or in this case organic material. Also, we’ve heard of everything under the sun, including flushing a whole pound of yeast, manure, worms, and other such methods of waste disposal. This is a fallacy! Your septic system does not require your assistance to get up and running. Simply said, the system must be followed.

You have enough “seeding” powers in your human waste to get it started. The one area in which the truth does show through is in maintaining the health of your system, particularly if you tend to use a lot of antibacterial or bleach products. This takes us to the second myth we’ll look at.

Additives Keep Old Systems Running Great

Seeding refers to the act of planting seeds. The term refers to the process of providing your system and bacteria with “seeds,” or in this case organic material, in order for them to flourish. As for the rest, we’ve heard of everything under the sun, such as dumping one pound of yeast or dung down the toilet, among other things. You have been deceived! Beginning the process of setting up your septic system is completely unnecessary. It is sufficient to follow the procedure. You have enough “seeding” powers in your human waste to get it going.

This is where the truth shines the brightest!

Pump Your Septic Tank every 5-7 years

A typical family may fill a septic tank to operational level in less than a week, without having to make any changes to their ordinary water usage. It is not necessary to pump the septic tank just because it is full or has reached a specific age. Simply let your healthy system to carry out its functions. In reality, as long as your tank is sized adequately for your home and your property is kept in good condition, your system will continue to break down and handle waste for many more years than you may expect.

Prior to booking a pumping appointment, you should always get your system examined.

There are a few situations in which you should refrain from pumping your tank, but we’ll cover those in more detail in a future blog article.

Once Installed, Septic Tanks Take Care of Themselves

Yes, this is correct! In conjunction with their biological processes and gravity flows, septic systems and tanks handle the majority of the job with little assistance from the homeowner. Because they are buried, they are readily forgotten. Despite the fact that you may not be required to take immediate action, your behaviors will have an impact on the overall health of your septic system.

You’ll Only Need One Septic System

In most cases, septic systems will not survive a lifetime. With adequate care and maintenance, systems can endure for 25 to 30 years on average. If you want your system to last as long as possible, learning how to do regular maintenance is priority number one. However, there are certain fallacies about septic systems that need to be dispelled. Understanding which stories are factual and which are nothing more than old wives’ tales can be difficult. Do you have any questions regarding some of the advice you’ve received?

Call Magneson Tractor Service today—we have the solutions you’re looking for. Do you have a disturbing myth that you would want us to investigate? Send us a message or leave a comment, and we’ll be pleased to sort out the crap from the truth about your situation!

Can You Put Dirt on Top of a Sunken Drain Field?

The principal method of disposing of home wastewater in many regions outside of the reach of municipal sewage systems is through septic systems. It is possible to temporarily disguise a problem by putting dirt on top of a leach field; however, the true answer to mending the system involves thorough examination and cleaning, as well as repairs or replacement of faulty components. While a freshly built tank may sink and require a little amount of more dirt to level the grass, the drain field should not require any additional material to be added on top of the soil already present.


A freshly built septic system may require an additional inch or two of earth as it settles into the landscape, but an existing system should not have dirt put over the drain field to prevent it from failing.

About Septic Systems

Homes constructed outside of towns and cities with a municipal sewer system must be equipped with a means of securely disposing of wastewater generated by sinks, showers, toilets, and clothes washers. An effective septic system is almost always the solution. In addition to the tank, which holds the solids and first rush of wastewater, a septic system includes a drain field, also known as a leach field or leach lines, which transports the water away from the house and allows it to soak into the soil.

The grease builds up to the top of the tank.

InspectionAPedia states that up to 36 inches of loose dirt is put over the top of the gravel and pipelines.

Aside from that, surplus water evaporates from the drain field, so leaving the impurities in its wake.

Sinking Soil and New Installations

The soil around and above the tank, as well as the pipes going to the drain field, may settle once a new septic system is installed. It is possible for the soil to get sunken even after it has been well tamped because of the weight of the tank, which might occur after heavy rains or spring thaws. Although covering the inspection and access ports with a few inches of earth to smooth over any uneven places would not harm the septic tank, you should avoid doing so in the future. The drain field, on the other hand, is a different story.

Don’t add any more dirt to the field since it will interfere with the evaporation of any extra water that has collected there.

There is only one exception: if rainfall is puddled on top of the drainage field. The University of Nebraska-Lincolnrecommends putting a little amount of dirt to shallow depressions in order to prevent puddles from accumulating.

Septic Drain Field Sinking

If the sunken area is more like a drain field sinkhole than a sunken region, you may need to have the perforated pipes repaired or replaced, whether they are new or old. The worst-case situation is that the drain field has failed completely and completely. A simple filling up of the sunken portions with soil or gravel will not resolve the issue. It will be necessary to either repair or replace the drain field. It’s possible that a vehicle was driven over the drain field and smashed the pipes, preventing the wastewater from draining all the way to the end of the leach lines and into the sewer system.

Eventually, a piece of the septic system may actually sink, or the soil may wash away, giving the area a sunken appearance.

Compacted soil obstructs this natural process and can result in sinking, wastewater discharge, and pollution of groundwater and neighboring wells, among other consequences.

In addition, only waste water and toilet paper should be flushed down the toilet.

Good and Bad Soils for the Septic System – Septic Maxx

One thing is certain no matter what type of septic system you have: it is dependent on soil to finish the process of moving wastewater from your property. The soil underneath your drainfield is critical in filtering all of the wastewater that is discharged from your septic system. The makeup of your soil is critical to the efficiency of your crop. In this section, we’ll go through the different types of soil and how they affect your septic system.

What’s in Soil?

Any randomly selected sample of soil will disclose the fundamental disintegration. It is made of 50% solid material and 50% pore space, which is the composition of soil. Organic plant materials, as well as three different mineral kinds (sand, clay, and silt) can be found inside the solid mass. Within the pore space, you will discover a space that is 25 percent filled with water and 25 percent with air (25 percent ). The texture of the soil is the factor that has the most influence on its ability to filter wastewater effectively.

Sand particles are the largest of all the particles since they are visible to the human eye and have a gritty feel, making them the most noticeable.

Clay particles are the tiniest, measuring only 0.002 mm in diameter, and they become sticky when wet. When it comes to effluent absorption by the drainfield, the texture is critical, which is why correctly balanced soils perform the best, as previously said.

Is My Soil Good or Bad?

Without the assistance of an expert, determining good drainfield soil may be challenging. During a soil evaluation, it is necessary to examine a variety of soil parameters, including texture, structure, density, and color. For effluent absorption, you want sandy soil that is not too coarse, well-drained soil, and naturally undisturbed soils, all of which are found in natural settings. In cases when the soil is too coarse, wastewater runs through it too rapidly for it to obtain adequate treatment.

Clay particles can also expand and obstruct soil passageways, further delaying the transport of wastewater through the system.

Hardpan is the term used to describe this ailment.

You can use this natural product once a month to increase the amount of beneficial bacteria in your body.

5 Things Homeowners Should Know About Their Septic Drain Field

There are certain distinctions in care, usage, and budgeting that you should be aware of, whether you’re a new homeowner with an existing septic system or considering about purchasing or building a home without sewer hookups. This document outlines three ways in which your budget will be affected if your wastewater is treated using a septic system. 1. You will not be required to budget for municipal sewer service. Because the municipal wastewater system normally processes all of the water, the cost of city sewage service is sometimes determined by how much water you purchase from the city.

A large number of homes with septic systems also rely on wells for fresh water rather than municipal water, which means you’ll likely save money in that department as well.

It is necessary to include septic maintenance in your budget.

Although you are not required to pay the city for the usage of your septic system, you will be responsible for the costs of maintenance if you want the system to continue to function properly.

It is possible that these maintenance and repair expenditures will build up over time, so you may want to consider setting up an emergency fund to cover any unforeseen repair bills.

You’ll also need to budget for the cost of a single inspection and begin saving for the cost of a tank pump.

Spreading the expenditures out over several months is the most effective budgeting strategy, even for an expense such as tank pumping that does not occur every year, because it allows you to better estimate the costs ahead of time.

You may need to set aside money for septic tank replacement.

The tank and leach field may not need to be replaced if you have a reasonably recent septic system and plan to sell your home within a few years.

If, on the other hand, your home’s septic system is more than a decade old, you’ll want to start looking into how much a new system would cost you as soon as possible.

For example, if the previous owners did not do routine maintenance or if the system was installed on clay soil, the system may need to be replaced.

It is a prudent decision to begin putting money aside in anticipation of this eventuality.

When you have a septic system, you may use these three strategies to budget differently.

Make an appointment with us right away if you’re searching for someone to pump out your septic tank or to complete an annual examination of your septic system. Our experts at C.E. Taylor and Son Inc. would be happy to assist you with any septic system assessment, maintenance, or repair needs.

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