- How often should my tank be pumped?
- What's the difference between pumping and cleaning a septic tank?
- How much should I protect the area where the septic system will be before building my home and after it's installed?
- How can I avoid septic system failure?
- How long will my system last?
- Who can repair septic system problems?
- Will trees and tree roots affect my system?
- Should my water softener discharge into my septic system?
- Should I use additives to boost system performance?
- Are garbage disposals bad for a septic system?
- How do I care for my system during an extended vacation or absence?
Answers
How often should my tank be pumped?
As a rule, tanks should be checked for solids buildup every year and pumped every three years.
In practice, however, the lifestyle of the family using the system and the size of the tank influence how often the tank should be pumped.
For example, families who use garbage disposals can expect a rapid buildup of solids in their tanks. Many tanks have risers with childproof caps installed on them to simplify solids removal so homeowners can routinely have their tanks cleaned every three to five years. These risers are also becoming more common because septic tank maintenance companies usually charge less if tanks are convenient to access.
Inspect your tank's effluent filter (if installed) via the riser every 6-12 months. If there is substantial buildup on the filter, have the tank cleaned. A properly functioning effluent filter protects the soil absorption field much more effectively than a baffle. If your tank does not have an effluent filter, consider installing one the next time you have your tank cleaned.
In any case, do not wait to pump the tank until the plumbing system backs up in your home. Solids overflowing from the tank can seriously damage the soil absorption system.
What's the difference between pumping and cleaning a septic tank?
When choosing a company to remove solids from your septic tank, ask if they thoroughly clean the tank and remove all solids. Septic system performance will not be improved if the company simply pumps out the liquid and leaves the solids behind.
Reputable companies flush removed liquids back into the tank to thoroughly agitate and remove settled solids. They also check the tank's baffles to make sure they are functional, and clean the tank's effluent filter (if installed).
How much should I protect the area where the septic system will be before building my home and after the system is installed?
Soil is the most expensive and important septic system component. As such, you should protect the soil in your absorption field from possible damage before and after installation.
With few exceptions, all Indiana septic systems must discharge into the soil. To function properly, that soil must be natural and undisturbed, not compacted. Compacted soil cannot disperse and treat wastewater effluent efficiently and can lead to system failure, and costly repairs.
To avoid soil compaction, do not put any structures on top of or on the downslope of the soil absorption field. And never drive any vehicle larger than a lawn mower on top of a septic system.
When possible, it is a good idea to maintain another area on your lot for another soil absorption field in case the system fails. This is required in some counties.
For more information, see Purdue Extension publication HENV-7-W, Indiana Soils and Septic Systems.
How can I avoid septic system failure?
If your septic system has been properly sited, designed, and installed, the rest is up to you. There are three basic things you can do to avoid failure.
- Have a septic system professional routinely remove solids from the septic tank.
- Avoid excess water use. Too much water entering the septic system can exceed the soil's ability to absorb it.
- Watch what you flush down the drain. Never pour substances such as motor oil, gasoline, paints, thinners, or pesticides down the drain. These materials pollute the groundwater and are often toxic to the organisms in your tank and soil that break down your wastewater. While not toxic, other items such as fats, grease, coffee grounds, paper towels, sanitary napkins, and disposable diapers can clog your septic system. Moderate use of household cleaners, disinfectants, detergents, or bleaches does little harm to the system, but avoid excess use.
When properly sited, designed, installed, and maintained, many Indiana septic systems will last 20 years or more.
If the system is not properly sited, designed, installed, or maintained, it may have a life of only a few months or years, and be very difficult and expensive to repair or replace.
Who can repair septic system problems?
If you have a septic system problem, immediately contact your local health department. Contact information for your health department can be found at www.in.gov/isdh/links/local_dep/index.htm.
Your health department should have a list of professionals who work in your county. Some Indiana counties require installers to be certified by the health department.
Will trees and tree roots affect my system?
Roots from trees and shrubs can invade and plug sewer lines.
Wastewater effluent is full of plant nutrients, including nitrogen and phosphorus, which attract roots to leaking septic tanks and to soil absorption fields. Roots can seriously damage septic tanks and distribution pipes by plugging pipes and cracking tanks, resulting in significant repair costs.
If there are trees near your soil absorption field, they should be as far away as possible from the point where effluent from the septic tank enters the drain field. If you're planting trees, remember to use their estimated root spread at maturity to determine where to place them. Often a tree's root spread is about the same as its height. For example, a weeping cherry may be expected to grow about 25 feet tall, so its root spread will be about the same and should be planted a minimum of 25 feet away from the soil absorption field. A mature oak might need to be 60 or 70 feet away.
Trees known for seeking water, such as poplar, maple, willow, and elm, should be planted at least 50 feet from the s oil absorption field. All other woody plants should be more than 20 feet away from soil absorption field. Although the root spread of these trees may eventually encompass a portion of the drain field, serious distribution line damage from the roots is unlikely because the lines are surrounded by gravel. Still, the potential for damage to the system exists.
Should my water softener discharge into my septic system?
According to Indiana State Department of Health Rule 410 IAC 6-8.1 all household wastewater must discharge to a septic system.
Even though water softener discharge does not contain pathogens, Indiana code requires that it be treated like other household wastewater from your drains or toilet.
There has been little research regarding the effects of water softener discharge on septic tanks. If you choose to handle water softener discharge in a system separate from your septic system, remember that softener backwash contains high salt concentrations, which can harm turfgrass and other plants.
Should I use additives to boost system performance?
There is no documented scientific evidence that yeasts, bacteria, enzymes, and chemicals marketed to septic system owners actually improve septic system performance.
In fact, some additives can cause solids in an overloaded tank to be re-suspended. That is, instead of staying on the bottom of the tank, the solids float back to the top. If these solids overflow, they can damage the soil absorption field.
Additives do not eliminate the need to routinely remove solids from your septic tank. Furthermore, it is unnecessary to add biological additives to your tank after it's cleaned or after your home is built, because the incoming household sewage contains a more than adequate amount of active microorganisms to promote decomposition.
For more information, see Purdue Extension publication HENV-13-W, Septic System Additives.
Are garbage disposals bad for a septic system?
Not directly, but they can cause solids to build up in septic tanks at about twice the normal rate.
Therefore, if you use a garbage disposal, you should have your septic tank checked or cleaned at half the usual time interval (for example, every 1½ to 2½ years instead of the normal three to five years). These solids must be removed before they reduce the tank's effectiveness, or overflow and damage the soil absorption field.
How do I care for my system during an extended vacation or absence?
Septic systems may sit idle for weeks or months.
In summer and fall an idle septic system probably will not be an issue. Indeed an idle system can even benefit the soil absorption field by allowing the soil to dry. Inactive periods allow the biomat (a layer of bacteria and other organisms that grows in a thin mat in the trenches of soil absorption fields) to decompose. This decomposition can rejuvenate a slow-draining septic system's performance because biomats can clog wastewater flow.
In winter, septic tanks should be buried deep enough to avoid freezing problems. If your septic system has a pump and distribution network (e.g., a mound absorption field), the system should be designed so there is never any standing water in the lines to reduce the possibility of freeze damage.
Even after a period of inactivity, the system should still have plenty of bacteria. The population may decrease while the system is idle, but microbes are remarkably resilient and will recover quickly upon your return.
Care and Maintenance | Building a New System or Making Repairs |
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