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.
- The leach field is a series of trenches that may be up to 100-feet long and 1 foot to 3 feet in width, separated by six feet or more, depending on local requirements, and sometimes constructed leaving space between the original lines to install replacement leach lines when needed. – paraphrasing USDA.
How do I calculate the size of my septic drain field?
- The size of the drainfield is based on the number of bedrooms and soil characteristics, and is given as square feet.
- For example, the minimum required for a three bedroom house with a mid range percolation rate of 25 minutes per inch is 750 square feet.
How big should my leach field be?
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.
Can a leach field be too deep?
Drain Field Depth The result is a drain field about 3 to 4 feet deep. Sometimes, however, a drain field may need to be a bit shallower and can result in drain pipes as close to the surface as 6 inches. Underground obstacles can cause this situation.
Can you have a septic tank without a leach field?
The waste from most septic tanks flows to a soakaway system or a drainage field. If your septic tank doesn’t have a drainage field or soakaway system, the waste water will instead flow through a sealed pipe and empty straight into a ditch or a local water course.
How far should leach field be from house?
Local codes and regulations that stipulate the distance of the septic tank from the house vary depending on the locale, but the typical minimum distance is 10 feet.
How many feet of leach line do I need?
REQUIRED SEPTIC TANK SIZE IN GAL. * A minimum of 150 square feet of trench bottom area is required. ** # gal X soil type multiplier 100 4.285 Note: Maximum length of any leach line is 100 feet. If more than 100 feet is required, then a distribution box with multiple lines will be needed.
How often does a 1000 gallon septic tank need to be pumped?
For example, a 1,000 gallon septic tank, which is used by two people, should be pumped every 5.9 years. If there are eight people using a 1,000-gallon septic tank, it should be pumped every year.
How far down is a leach field?
A typical drainfield trench is 18 to 30 inches in depth, with a maximum soil cover over the disposal field of 36 inches.
Does a leach field need to be level?
The water level should always be at the level of the drain line connecting the septic tank to the leaching field. If the water level is higher than the drain line, it means that the leaching field cannot hold any more water and it is backing up into the septic tank.
How deep is the gravel in a leach field?
Depending on local regulations, each of the trenches should be between 1 and 3 feet in depth and about 18 inches wide. A layer of gravel should be placed at the bottom of the trench to a depth of about 1 foot.
How many Infiltrator chambers do I need?
As a general rule, trenches ‘fingers’ should be no longer than fifty feet ( 12 or 13 Infiltrators long ) for best function and most even effluent distribution. Unless you are installing as a “bed” system (where the chambers are right next to each other), leave at least six feet of undisturbed soil between fingers.
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.
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 move 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.
- 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.
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.
Septic systems: How big should my drainage field be?
What every homeowner who is considering installing a septic system must consider is the amount of land they need to dedicate to septic field, which is where liquid waste will eventually be released into the soil. Even in the country, yard space is valuable, and you don’t want to give it up to a field that’s too large for your needs or to a neighbor’s livestock. This is especially true when you consider the fact that once the field is in, you won’t be able to use that space for anything else in the future.
- However, if you make your field too tiny, you’ll have a lot of headaches.
- Who has a need for that?
- But keep in mind that this is just a rough estimate.
- The two most important factors to consider are, first, the amount of waste you intend to send through the system, and, second, the condition of the soil in the drainage field, both of which are critical.
- If the soil has good percolation conditions—for example, if it’s comparably sandy and waste water seeps down with little resistance—a seepage field of 4,500 square feet (for example, 100 feet long and 45 feet wide) is appropriate for a three-bedroom house with regular waste production.
- Figure 9,000 square feet, which is a significant change.
- The percolation rate of waste water is quicker in hotter regions.
- It will be up to your contractor to select how much larger it will be.
- When deciding where you want your septic system to be installed in your yard, you should take your local zoning code into consideration.
- It can be as much as 100 feet or more in extreme circumstances.
- According to others, it should be located as near to the home as feasible.
But some believe that the system should be located as far away from the building as possible, in an open area where it will be simpler to reach in the event of a crisis.
Assessing Septic System Sizing For Tank And Drain Field
However, it is a common misconception that the size of the system is determined by the size of the home; however, this is not completely correct. The size of the septic system is normally established by taking into consideration how many bedrooms the house has, or more specifically, how many projected residents there will be and how much water will be used on a daily basis (litres per day). Because everything that goes into a septic system must eventually come out, water consumption is a crucial consideration when sizing a septic system.
The size of a septic system must be determined by ensuring that the septic tank and drain field are both large enough to handle the amount of wastewater created by the residents of the property.
Things to Consider when Sizing a Septic Tank
It is necessary to size a septic tank appropriately so that the retention time — the amount of time that wastewater effluent remains in the tank before being discharged to the drain field — is long enough to allow heavier solid particulates, such as fats and oils, to settle to the bottom of the tank as sludge and lighter solids, such as grease and oils, to float to the top of the tank and join the layer of scum that has formed above it.
The presence of a significant amount of liquid in the tank is required for this method to be successful in order to aid the settling process.
If you have a three-bedroom house or a property with fewer than three bedrooms, you should have at least 850-1000 gallons of storage space in your septic tank (3900 litres).
Septic tank capacity based on the number of bedrooms ” data-image-caption=”Septic Tank Sizing in British Columbia Based on Bedroom Count” data-medium-file=”ssl=1″ data-medium-file=”ssl=1″ data-large-file=” ssl=1″ loading=”lazy” src=”is-pending-load=1 038;ssl=1″ data-large-file=” ssl=1″ loading=”lazy” src=”is-pending-load=1 038;ssl=1″ alt=”septic tank sizing” width=”669″ height=”377″ alt=”septic tank sizing” width=”669″ height=”377″ srcset=”data:image/gif;base64,R0lGODlhAQABAIAAAAAP/yH5BAEAAAAALAAAAAABAAEAAAIBRAA7″ data-recalc-dims=”1″ data-lazy-src=” is-pending-load=1 038;ssl=1″ data-recalc-dims=”1″ data-lazy-src=” is-pending-load=1 However, there are a few extra considerations that should be taken into consideration.
For example, if a trash disposal machine is installed in the kitchen, it is often estimated that the daily flow would rise by at least 50% as a result of the organic waste generated, which must be handled inside the septic system.
It is possible that a grease interceptor will be required.
Although crucial to remember, the septic tank only serves to partially treat waste water; the remainder, as well as liquid effluent disposal, takes place in a drain field, which must be properly designed in order to function properly.
Things to Consider when Sizing a Drain Field
It can be difficult to determine the most appropriate size for a drain field because it must take into account not only the amount of water used by the household and the rate at which it is used, but also the soil characteristics of the site where the drain field will be constructed, as well as the quality of the effluent entering the drain field. It is also possible to create trenches at a shallow depth — in this instance, trenches are partly below ground and partially covered, or “at grade.” As shown, the infiltration surface is at its original grade, and the system has been covered with cover dirt to prevent erosion.
The horizontal basal area ONLY (not including the sidewall area) should be at least equal to the AIS (Daily Design Flow divided by the Hydraulic Loading Rate or HLR).
The area of the trench infiltrative bottom required equals the area of the infiltrative surface (AIS) Hydraulic loading rate divided by daily design flow equals Area of the Infiltrative Surface (AI).
Sizing a Septic Drain Field, Calculation Example
1300L/day daily design flow for a three-bedroom house with a high permeability ratio of 30 L/day/m2 for Loamy Sand (high sand content with a tiny percent of clay) and trenches 0.6 m wide. Trench bottom area is calculated as 1300L/D/m2 x 30L/D/m2 = 43.33 m2. trenches total length = 43.33 0.6 = 72.2 m total trench length We need to know how soon the soil can absorb the wastewater because the soil is responsible for absorbing it. It is known as the percolation rate, which is the rate at which water may be absorbed by the soil.
It is possible for sewage to rise up and pool on the surface of the soil, resulting in an unpleasant and unhealthy environment; however, if the soil percolation rate is too fast, the effluent will not be properly treated before it filters into the groundwater, resulting in an unpleasant and unhealthy environment.
Gravelless systems consisting of a single or many pipes are defined as having an effective trench width equal to the outer diameter of the pipe or pipe bundle.
A more cautious method would be to use the actual exposed interior dimensions width of the chamber at the trench or bed bottom, rather than the nominal interior dimensional width.
Geocomposite systems have an effective trench width defined as the outside dimensions (or outside dimensions plus one) of the bundle(s) in direct contact with the trench or bed base (or sand layer, where used).
As a potential system reserve region, the inter-trenching spacing might be taken into consideration. If the trench width is less than 30.5 cm (1′) or greater than 90 cm (3′), the depth should be reduced. For any one lateral in a gravity distribution system, the length of the trench should not be larger than 15 m (50 feet). Gravity systems that are not dosed should preferable employ shorter laterals (less than 50′ in length). Except in the case of pressured shallow narrow drain fields, the spacing between center lines should not be less than 1.8 m (6′) from center line to center line.
GRAVITY TRENCH DISTRIBUTION DESIGN CONSIDERATIONS
There should be no use of gravity flow for distribution areas more than 152 linear metres of trench width 610 mm (500 lineal feet/2 foot wide trench) or for distribution systems greater than 93 m2 (1,000 ft2) infiltrative surface area. Gravity systems that are greater than this should only be built if they are DOSED with water. Ideally, these systems should employ dosing to sequential distribution, pressure manifold distribution, or dose to Distribution Box as their distribution methods (D-Box only for slopes below 15 percent ).
Dosing systems should be planned and constructed in accordance with the specifications in this document (linked standard).
Pump Tank Sizing
The size of the tank is determined by the sort of pumping setup that will be employed. The following sections provide recommendations for chamber selection based on recommended volume guidelines. In a pump tank, the working volume is the space between the tank’s interior bottom and the invert of the input pipe’s invert. As long as the valve and union are accessible above the level of the alarm reserve volume, the depth from the invert of the inlet to the underside of the tank lid could be included in the alarm reserve volume if the pump tank is installed at an appropriate elevation (see worksheet in Appendix P) in relation to the preceding tank (for example, a septic tank).
- Design Flow on a daily basis.
- Minimum of 50% of Daily Design Flow must be set aside as alarm reserve volume (over and above the alarm float on, up to the maximum allowable effluent level).
- Summary: When it comes to septic systems, the kind of system (whether it is a type-1, type-2, or type-3 system) will have an impact on the quality of the effluent that is discharged into the drain field from the tank.
- This is because cleaner effluent will require less treatment in the drain field.
- The examples above are for conventional type systems, which are the simplest to calculate.
- The hydraulic loading rates of both the soils and the wastewater treatment level are used to determine the appropriate size of a septic system.
- In order to assess the vertical separation of soils from any restrictive factors and to enter data on hydraulic load rates through percolation testing and soil texturing, there is a significant onus on the contractor to undertake thorough site investigations.
High-volume fixtures and garburators will have an adverse effect on a septic system since they will add significant amounts of organics that will not adequately decompose as well as excessive volumes of water use. As a result, they must be scaled appropriately.
What Size Septic Tank Do I Need
The size of an underground septic tank is referred to as its total volume handling capacity in this article, and it will be discussed in further detail later in this article. For additional information on above-ground septic tanks and systems, see our page on above-ground septic tanks. The minimum septic tank capacity requirements are determined by a variety of variables. State, county, and/or city regulations may specify permitted tank sizes, as well as tank materials and installation.
The size of the septic tank will vary depending on whether it is intended for domestic or commercial usage; in this section, we will cover residential use.
Shortly stated, the required size of a septic tank will be determined by the following factors: (1) the specific septic system type; (2) local government requirements; (3) the compatibility of the ground geology; and (4) the anticipated volume of wastewater depending on the size of the residence.
However, this is not true.
Furthermore, plastic septic tanks will not corrode, are weatherproof, are waterproof, are less expensive, are lighter, and are easier to build.
1) The Specific Septic System Type
There are seven different types of septic tank systems, and the size of the tank required will vary depending on the system you choose. The scope of this article does not allow for a comprehensive discussion of each system type and its associated size requirements. We are referring to traditional gravity-fed anaerobic septic systems in this context when we say “system type.” The anaerobic septic system is the most prevalent type of septic system, and it is the one that most people think of when they imagine a septic tank.
- The following systems are available: conventional, gravity-fed, anaerobic systems
- Above-ground septic systems
- Pressure systems
- Anaerobic systems
- Mound systems
- Recirculating sand or gravel filters systems
- Bottomless sand filters systems
If your septic tank system is anything other than a traditional, anaerobic system, the instructions in this page may not be applicable in their entirety to your situation.
2) Local Government Regulations
The regulations for septic tanks imposed by local governments vary widely across the United States. In part, this is due to the significantly diverse soil geography and water features that exist from state to state and can even differ by a few miles in some cases. In order to determine the appropriate septic tank size and the best location on the property for installation, it is essential to consult with local government regulations first. Take, for example, theWastewater Treatment Standards – Residential Onsite Systemsdocument from the New York State Department of Health, which provides a comprehensive informational overview of codes, rules, and regulations frequently promulgated by governing bodies, as well as common terminology and definitions in the industry.
3) Suitability of the Ground Geology
The subterranean soil type has a significant impact on the efficacy of the system and, consequently, the size of the septic tank. This topic is highly tied to the rules of the local government. In most cases, it is related to the standards and recommendations of a designated authority that regulates septic tank installations, which is typically the department of health. In order to determine whether or not the ground is suitable for a septic tank system, a trained specialist must come out to the prospective installation site and conduct a series of tests.
A perc test will assess whether or not the subterranean soil is capable of handling and filtering septic tank effluent in an appropriate manner.
Whether you are hiring an experienced professional or doing it yourself, it is your obligation to contact your local oversight agency and arrange for perc tests and/or ground area evaluations to be performed.
4) The Expected Volume of Wastewater
The typical amount of wastewater that will be generated and that the septic tank will be able to manage is the most essential factor in determining the size of the septic tank that is required. In a home with simply a septic system, all wastewater is disposed of in the septic tank unless a separate system for managing greywater is in place to handle the waste. In order to calculate and approximate these values for residential dwellings, business structures, and facilities, extensive study has been carried out.
Starting with a 1000-gallon septic tank for residential usage, the advice is to go from there.
Some experts propose adding an additional 250 gallons of septic tank capacity for each additional bedroom over three bedrooms.
This is frequently the case when considering the situation collectively for the entire household rather than individually.
This article has demonstrated that septic tank recommendations are extremely diverse and depend on a variety of factors like where you reside, local government rules, subterranean soil type, house size, and the amount of wastewater that your unique home is predicted to produce.
Minimum Septic Tank Capacity Table
For further information on the minimum septic tank capacity dependent on the number of residential bedrooms, please see the following table:
|Number of Bedrooms||Minimum Septic Tank Size||Minimum Liquid Surface Area||Drainfield Size|
|2 or less||1000 – 1500 Gallons||27 Sq. Ft.||800 – 2500 Sq. Ft.|
|3||1000 – 2000 Gallons||27 Sq. Ft.||1000 – 2880 Sq. Ft.|
|4||1250 – 2500 Gallons||34 Sq. Ft.||1200 – 3200 Sq. Ft.|
|5||1500 – 3000 Gallons||40 Sq. Ft.||1600 – 3400 Sq. Ft.|
|6||1750 – 3500 Gallons||47 Sq. Ft.||2000 – 3800 Sq. Ft.|
Take note of the following in relation to the table above:
- As defined by the State of New York, the Minimum Liquid Surface Area is the surface area given for the liquid by the tank’s width and length measurements. The range of Drainfield Sizes is depending on the kind of groundwater present. The State of Michigan provides the above-mentioned drainfield recommendations, which might vary greatly depending on local standards and terrain.
Additional Thought: Can a Septic Tank Be Too Big?
In the absence of consideration for cost, it is reasonable to ask: “Can a septic tank be too large?” The answer is a resounding nay. As long as the septic tank is placed appropriately, it is impossible for a septic tank to be too large; the only thing that can happen is that it is too little. According to the majority of suggestions, constructing a larger-capacity septic tank is frequently the safer and more preferable solution. The following are the reasons behind this:
- With a bigger septic tank, you can adapt for changes in household consumption, such as those caused by parties or long-term guests. In the event that your family grows in size or you want to make improvements to your house, such as adding more bedrooms and bathrooms or installing new plumbing fixtures, having a bigger septic tank can save you the expense of installing a new tank.
Takeaways | What Size Septic Tank Do I Need
The septic tank size recommendations offered here are merely that: suggestions. They are built on a foundation of information gathered from government and academic sources. The actual size of the septic tank you require will vary depending on the factors discussed in this article. There is no “one-size-fits-all” solution when it comes to determining the appropriate septic tank size for your property. There is a great deal of variation depending on where you reside. With addition to providing a basic insight into the septic tank and system size that may be most suited to your application, the providedMinimum Septic Tank Capacity Tablecan also assist in cost estimations.
Before beginning any septic tank installation project, check and double-check with the state, city, or local county’s agency that is in charge of septic tanks, soil testing, and permissions.
If you’re searching for a chart of tank sizes, have a look at our page on the many sizes and quantities of septic tanks available.
They are available in both single chamber and double chamber designs.
Sewage System Sizing
Adding more plumbing fixtures, such as separate showers with whirlpool tubs instead of tub/shower combos, double lavatories, bidets, and other similar items, has been demonstrated to increase the quantity of wastewater created by a residence, according to research. Any two extra fixtures may result in an increase in the size of the septic tank and/or drainfield. If you want to add a number of fixtures, consulting with our Sanitarians early on will allow you to determine the necessary size of the septic tanks and drainfields to be installed.
Things to Keep in Mind
- It is recommended that you use the sizes mentioned for primary drainfield regions. The sum of the primary and reserve drainfield areas is the total drainfield area that is required. Effluent filters are highly recommended and may be necessary on some sites and on alternative on-site sewage systems. The reserve area is 1.5 times the size of the principal drainfield. In the wastewater exiting the septic tank, effluent filters remove tiny solid particles, preventing the particles from entering the drainfield. Consult the manufacturer’s instructions for proper usage and maintenance.
An additional bedroom, study, den, or similar area that has the potential to be transformed must be included in the total number of bedrooms.
What size of septic tank do I need?
Probably one of the last things on your mind when you are constructing a new home is the location of your septic system. After all, shopping for tanks isn’t nearly as entertaining as shopping for cabinetry, appliances, and floor coverings. Although you will never brag about it, your guests will be aware if you do not have the proper septic tank installed in your home or business.
septic tanks for new home construction
The correct size of the septic tank is determined primarily by the square footage of the house and the number of people who will be living in it. The majority of home septic tanks have capacities ranging from 750 to 1,250 gallons. A 1000 gallon tank will most likely be required for a typical 3-bedroom home that is less than 2500 square feet in size. Of course, all of this is dependent on the number of people who live in the house as well as the amount of water and waste that will be disposed of through the plumbing system.
For the most accurate assessment of your septic tank needs, you should speak with an experienced and trustworthy sewer company representative.
planning your drainfield
Here are some helpful hints for deciding where to locate your drainfield when you’re designing it.
- Vehicles should not be allowed on or around the drainfield. Planting trees or anything else with deep roots along the bed of the drain field is not recommended. The roots jam the pipes on a regular basis. Downspouts and sump pumps should not be discharged into the septic system. Do not tamper with or change natural drainage features without first researching and evaluating the consequences of your actions on the drainage field. Do not construct extensions on top of the drain field or cover it with concrete, asphalt, or other materials. Create easy access to your septic tank cover by placing it near the entrance. Easy maintenance and inspection are made possible as a result. To assist with evaporation and erosion prevention, plant grass in the area.
a home addition may mean a new septic tank
Do not make any big additions or renovations to your house or company until you have had the size of your septic system assessed. If you want to build a house addition that is more than 10% of your total floor space, increases the number of rooms, or necessitates the installation of new plumbing, you will almost certainly need to expand your septic tank.
- For a home addition that will result in increased use of your septic system, your local health department will require a letter from you that has been signed and authorized by a representative of your local health department confirming that your new septic system is capable of accommodating the increase in wastewater. It is not recommended that you replace your septic system without the assistance of a certified and competent contractor.
how to maintain your new septic system
Septic tank cleaning and septic tank pumping services are provided by Norway Septic Inc., a service-oriented company devoted to delivering outstanding septic tank cleaning and septic tank pumping services to households and business owners throughout the Michiana area. “We take great delight in finishing the task that others have left unfinished.” “They pump, we clean!” says our company’s motto. Septic systems are something we are familiar with from our 40 years of expertise, and we propose the following:
- Make use of the services of a qualified specialist to develop a maintenance strategy. Make an appointment for an annual examination of your septic system. Utilize the services of an effluent filter to limit the amount of particles that exit the tank, so extending the life of your septic system. Waste items should be disposed of properly, and energy-efficient appliances should be used. Make sure you get your septic system professionally cleaned every 2 to 3 years, or more frequently if necessary, by an experienced and qualified expert
- If you have any reason to believe that there is an issue with your system, contact a professional. It is far preferable to catch anything early than than pay the price later. Maintain a record of all septic system repairs, inspections, and other activities
common septic questions
Here are some of the most frequently asked questions by our septic customers.
How do I determine the size of my septic tank?
If you have a rectangular tank, multiply the inner height by the length to get the overall height of the tank. In order to find out how many gallons your septic tank contains, divide the number by.1337.1337
How many bedrooms does a 500-gallon septic tank support?
The exact size of the septic tank is determined mostly by the square footage of the house and the number of people who will be living in it. The majority of home septic tanks have capacities ranging from 750 to 1,250 gallons. A 1000 gallon tank will most likely be required for a typical 3-bedroom home that is less than 2500 square feet in size.
How deep in the ground is a septic tank?
Your septic system is normally buried between four inches and four feet underground, depending on the climate.
Your Go-To Guide for Absorption Field Sizing
A thorough consideration of minimum setback requirements should be included in the design of every system. Check the distance between the crawl space foundation and the inlet of the septic system.
Interested in Systems/ATUs?
Receive articles, news, and videos about Systems/ATUs sent directly to your email! Now is the time to sign up. Systems/ATUs+ Receive Notifications When designing a new septic system or repairing an existing one, the size of the absorption field should always be considered one of the most critical design considerations. There are several aspects to consider when sizing an absorption field, including setbacks from wells and property lines, soil and other geological features, as well as the general appropriateness and accessibility of a given location.
- Minimum statewide regulations are in place in my home state of Missouri, and these are sometimes supplemented by additional local regulations.
- The procedure is subject to the requirements of the local governing body.
- State guidelines, or a mix of state and county or local rules, may be used to accomplish this.
- In rare cases, some agencies may demand both in order to be compliant.
- The findings of a perc test are based on how long it takes for the soil to absorb a certain amount of water in a sample hole with a specific diameter and depth (see figure).
- When it comes to soil analysis, there are a number of very specific conditions and requirements that must be met.
- Factors affecting soil evaluation It may also be necessary to conduct a soil evaluation in order to determine the proper size of the field.
- Only qualified individuals are permitted to conduct these types of tests in accordance with the requirements of the governing authority.
- The pace at which soil is loaded Perc tests and soil evaluations both provide information that can be used to calculate the soil loading rate.
- You have the single most essential element in the equation of sizing an absorption field after the results of the chosen test (percolation, soil evaluation, or both) have been obtained.
An illustration of a conventional system is as follows:
- Number of bedrooms: 3
- Soil loading rate: 0.4
- Number of gallons required per bedroom: 120
- Soil loading rate: 0.4
To calculate this, the following formula might be used:
- 450 lineal feet of 2-foot-wide conventionalaltrenches using 4-inch perforated PVC and gravel
- 3×120 = 360 gallons per day
- 360/0.4 = 900 square feet of conventionaltrench bottom
Alternatives for determining the size of the absorption field You should keep in mind that there are numerous scenarios available when determining the size of the absorption field. For example, your local regulatory body may permit the use of an alternate absorption trench material in lieu of 4-inch pipe and gravel in certain circumstances. This alternate medium may be able to fit into your 24-inch-wide trench and qualify as the equivalent of a 36-inch-wide trench (approximate width varies by authority), reducing the needed field to merely 300 lineal feet of trench (approximate width varies by authority).
- Maintain your focus on the fact that the stats we’ve examined thus far are exclusively for the trenches.
- The regulatory body will impose a minimum spacing distance between the structures.
- It is important to remember to leave enough space for the pipes that run from distribution devices to laterals.
- I, on the other hand, feel that the absorption field is of critical importance.
- It also serves as a garbage place.
- Jon Hancock is the owner of Envirotek Systems, which is based in Kimberling City, Missouri.
- Pay him a visit at
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.
Prior to discharging wastewater into the environment, several alternative systems are designed to evaporate or disinfect the effluent.
Specifically, this is how a typical conventional septic system works:
- 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 type of bacteria that can 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:
- You make use of well water. In your home, the water pipe that brings water into the house does not have a meter. In the case of a water bill or a property tax bill, you will see “$0.00 Sewer Amount Charged.” It is possible that your neighbors have a septic system
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
Septic System Frequently Asked Questions
A septic system, also known as a septic tank, is an underground system that treats the sewage that flows from your home before disposing of the treated, cleaner water. Septic systems are commonly found in residential areas. The treated water is subsequently re-introduced into the environment through filtration. This is critical because untreated sewage may harm nearby streams and water systems, as well as the soil around the perimeter of your septic system. Because your septic system is designed to cleanse and filter sewage, it is critical that it is in proper operating order.
What is a Drainfield?
The drainfield, also known as the leach field, is the area where the water from your septic system is directed after it has been treated and filtered. It is necessary to construct a drainfield in order to ensure that water is distributed uniformly back into the soil.
How do I find my septic system?
If you’re fortunate enough to have a contemporary septic system in your yard, it may be equipped with an access lid that is visible from the ground floor. If this is the situation at your residence, locating your septic system is as simple as taking a few steps into your backyard. It’s unfortunate that this isn’t true for older septic systems. It’s possible that you may locate an older system in your home by checking for greener, faster-growing grass or even an area with less growth than the rest of your yard if you live in an older home.
This will show you exactly where your septic system is located in your yard, if you have one.
You’ll need to look for the location where your septic system’s sanitary line exits your home and follow that line until you find your septic tank, which will take some time.
If you are unable to discover your septic system, your yard may need to be dug up by a septic system installation in order to locate your septic tank as a last option.
How long do septic systems last?
Septic systems are not designed to endure for a specific number of years, thus there is no defined time frame. In the event of adequate maintenance, you may expect your septic system to last several decades before it has to be replaced; but, if your system fails or deteriorates as a result of bad care, its lifespan will be drastically diminished. In order to obtain an accurate estimate of how much longer the life of your septic system may be extended, you must first have it checked thoroughly by an experienced septic system installation or repairer.
However, if you are confident that your tank is in good condition, the date of installation should provide you with an indication of how long it will endure.
What’s the advantage of installing a newer septic system rather than an older system?
Although it is not required to install a new system, there are advantages to having a modern septic tank rather than an older one. For starters, when you get a new septic tank, you can be confident that it will serve you for decades if it is properly maintained, and you will not have to worry about it being “too old.” Additionally, newer systems have been modified to reduce the likelihood of your system becoming clogged, and if something does go wrong with a new system or when it comes time to have your septic system pumped, a new system will likely be easier to locate because they are frequently constructed with ground-level lids.
New septic systems also provide a further treatment for your waste water, allowing it to be cleaner before it is released into the surrounding environment.
How much does a new septic system cost?
Installation of new septic systems may be a significant financial commitment, with costs typically reaching tens of thousands of dollars. Whenever you have to replace an old septic system, you should look into financing options that will make it easier for you to pay for a new septic system in the long run. Obtain additional information from a septic system installation company about how to obtain septic systems at the most competitive prices while also taking advantage of low-interest financing options.
How big is my septic tank?
Septic tank capacity is determined by the amount of water consumed in your property as well as local codes and requirements. Check with your local health agency to find out how big your tank is before installing it.
Why should my septic system be pumped out?
Without regular pumping, the gases emitted by human waste accumulate in your septic system, increasing the risk of septic tank damage and the need for more frequent pumping. The regular pumping of your septic system will allow you to limit the rate at which your tank deteriorates and save money in the process. It’s crucial to remember, though, that degeneration is unavoidable in the long run. It is only via regular maintenance, such as pumping your tank, that your septic system will survive longer.
Does my tank need to be dug up to know if it needs to be pumped?
Risers are commonly found in newer septic systems, which allow you to access your tank from the ground level through a lid. It is straightforward for any septic system professional to determine whether or not your yard has risers placed, and whether or not it is necessary to pump it. If, on the other hand, your tank cannot be accessible from the ground level, it will need to be dug up in order to determine whether it has to be drained. Instead of inspecting your septic system to see whether it needs to be pumped on a regular basis, set a timetable for having your system pumped every 2-3 years.
Why should I have risers and lids installed on my septic system?
As a result, when it comes time to find, pump, or repair your septic system, risers are the best choice since they provide ground-level access to your system. Having a septic system lid will allow you to mow your lawn while still being able to locate your system with little difficulty. Lids and risers also have the advantage of being accessible all year round, as opposed to earlier septic systems that could only be accessed by digging a trench through your yard.
If your septic system has to be pumped or repaired for any reason during the winter months, getting beneath layers of frozen earth can be difficult, if not impossible, and you may be forced to wait until the spring to have access to your tank again.
How often should my septic system be pumped out?
A typical septic system contains a 1,500-gallon tank, which needs to be pumped around every 2-3 years for a household of four, according to industry standards. If you have less than four people living in your house, you will most likely be able to pump your septic system every five years rather than every three. You should speak with your local health agency to determine the exact size of your tank, and you should consult a septic system business to determine how frequently your tank should be pumped based on the size of your family and the size of your septic tank.
Do I need to have the septic tank pumped if I’m selling my house?
Consult with your local health department to learn about the restrictions that apply to your region of residence. Generally speaking, as long as your septic system has been pumped on a regular basis by a licensed septic system company and recently enough for the new homeowners to be able to live there for a year or two without having to pump the septic system, you should not be required to have it pumped again in the near future.
How do I find someone to pump my septic system?
It is important to be aware that not all septic system companies are licensed and that not all companies properly dispose of or recycle the waste they pump from your septic system when you are looking for one to pump it. Finding a firm that complies with EPA standards should be your first concern, and then you should look at price, how pricing is split down, and which company is delivering the most honest, economical, and dependable service should be your next consideration. Investigate business evaluations, and when you select a septic system provider to pump your septic tank, be certain that they do the work properly, leaving enough water and waste to keep the sewage decomposing while leaving no visible trace more than a few inches of waste behind.
How much does it cost to have my septic system pumped?
It is recommended that you call many pumpers before making a selection, and that you ask as many questions as possible to ensure that you are receiving the best service for your money. Pumping may cost upwards of $200, so it is always wise to shop around before making a decision. You should not consider it a waste of money to have your septic system pumped when the time comes. By correctly maintaining your septic system, you may avoid spending tens of thousands of dollars to replace your septic system long before it should have been replaced in the first place.
What happens if I don’t have my septic system pumped?
The sediments will pile up in your septic tank if you don’t pump it out regularly, ultimately overflowing into the drain field and clogging the drain field. Backups can occur, causing damage to your property and even necessitating the replacement of your drain field, which can be a very expensive error.
I just had my septic system pumped. Why is it full already?
Septic systems are designed to refill quickly because the purpose of pumping is not to remove water but rather to remove non-biodegradable waste, and the water itself is not the point of pumping. Once your septic system has been pumped and you begin to use the water in your house, your tank will quickly refill in order to maintain good operation of the system.
If the water level rises to a point where it is above the outlet line, contact your septic system service provider for assistance immediately.
What do you look for when inspecting my septic system?
Due to the fact that the purpose of pumping is not to remove water, but rather to remove non-biodegradable waste, septic systems are designed to be quickly replenished. Upon completion of the pumping and use of the water in your home, your septic tank will quickly refill in order to maintain proper functionality. If the water level rises to a point where it is above the outlet line, contact your septic system service provider for help.
The drains in my home aren’t draining as quickly as they normally do. Does this have to do with my septic system?
Drains that are clogged and that empty slowly are not necessarily a big source of concern. Before presuming that there is an issue with your septic system, check sure that there isn’t anything obstructing your drain first. In the case of one plumbing fixture in your house that is draining slowly, it is likely due to clogging; however, if all of the drains in your home are slow or leave waste backed up, it is probable that your septic system requires inspection and may even require pumping.
What happens when my septic system fails?
Symptoms of a failing septic system may include minor issues such as drain breaks or pipes that have been stopped, which can be caused by tree roots intersecting with the system. Septic system failure, on the other hand, might indicate that your septic tank has degraded to the point that it cannot be repaired and must be replaced. A blocked drainfield will hopefully not become your problem because it is the most expensive component of your system to replace; nevertheless, if it does, you must act quickly to make the necessary repairs or else your waste will continue to back up, perhaps causing damage to your property.
You’ll need to replace the drainfield as soon as possible to avoid further pollution of drinking water sources.
How do I prevent my septic system from failing? How can I properly maintain my septic system?
Your septic system should degrade at a normal rate over the course of several decades if you maintain it on a regular basis. Maintenance normally consists of getting your septic system pumped on a regular basis and making certain that you do not flush or wash anything down the drain that might block your septic system.
What shouldn’t I flush down the toilet?
As a general rule, only human waste and toilet paper should be flushed. There are several reasons why flushing medicine down the toilet is not a good idea. First, medication might kill some of the bacteria in your septic tank, which is necessary to break down solid waste. Second, drugs can pollute adjacent well water. In addition, you should avoid flushing feminine hygiene items, paper towels, tissues, hair, cat litter (even if it is flushable), diapers, wipes, condoms, cigarettes, and anything else that seems to be inorganic and shouldn’t be flushed down the toilet.
What shouldn’t I pour down the drain?
Grease from the kitchen, motor oil, anti-freeze, gasoline, paint, and food should not be flushed down the toilet or drain.
You should avoid flushing anything down your drain other than soap and water, and you should especially avoid flushing any form of chemical down your drain that should not be recycled back into the environment, such as fertilizer.
Is using a garbage disposal bad for my septic system?
Using a trash disposal will result in the requirement to pump your septic system more frequently than you would otherwise need to do if you avoided flushing food particles down your drains. Too much food collection in your tank might cause your drainfield to clog since the microorganisms in your tank are not capable to digesting it. When using a trash disposal, check with your septic system company to find out how frequently the disposal should be serviced.
Should I add bacteria to my septic system?
Aside from being completely useless, introducing bacteria to your septic tank is also highly discouraged. The bacteria produced by human waste is sufficient to break down the solid sewage in your tank without the need of bacteria supplements or other methods. If, on the other hand, several members of your household are taking medications, these will enter your septic system through human waste and kill some of the beneficial bacteria in your tank, causing it to malfunction. Please contact the company that installed your septic system to determine whether or not you should be concerned about the amount of bacteria-killing substances entering the system.
There’s a strong sewer odor outside of my house. Could this be my septic tank?
Strong sewage smell coming from your yard could be coming from your septic system, but it could also be coming from something else entirely. Identifying the source of the smell is important. Check for propane or gas leaks in your home before concluding that your septic system is at fault; however, if your gas or propane lines are not leaking, determine how long it has been since you had your tank pumped, and whether there is any sewage waste in your yard or other signs of septic system failure before making your final decision.
Can my septic system contaminate nearby water?
It is possible for your septic system to pollute surrounding water sources if it is not properly managed or fails completely. In the event that you suspect that your septic system is failing, make sure that it is routinely pumped and inspected by an expert.
My gutters’ downspouts drain into my yard above my septic system. Is this a bad thing?
The drainage of your gutters into your yard above your septic system, and particularly into your drainfield, can be hazardous to your septic system. All water should be diverted away from your septic system in order to minimize flooding and damage to your septic system’s tank or drain field.