How Does a Mound Septic System Work?

A traditional septic system uses a drain or leach field that filters the effluent that comes from the septic tank before it enters the ground water. However, not all areas can facilitate a drain field, either due to the type of soil or environmental concerns. An alternative to a drain field is a mound system, a filtering element that is created above ground. If you are considering adding a septic system or need to replace a drain field, here is what you need to know about mound septic systems.

Mound System Basics

Mound septic systems work similar to a traditional system but are a bit more complicated. As wastewater or effluent exits the tank, it is sent to a dosing chamber instead of a gravity distribution box. The dosing or pumping chamber regulates how much effluent is allowed to the enter the mound filter to ensure it is not overloaded. The mound is built with a network of pipes that transport wastewater from the dosing chamber. Wastewater filters down through the mound sand, removing contaminants before it reaches the ground surface underneath.

Mound systems offer a way to install a septic system in almost any area, even when a leach or drain field is not possible. They are more expensive to install, but if maintained correctly, they can last for decades. Although they do require a large mound to be in your yard, it can and should be planted with grass or small plants.

If you need to use a mound septic system, it is vital to stay on top of maintenance and use preventive septic care habits. Routine inspections and pumping the tank can help prevent issues that can damage your mound system and protect your investment.

Posted on behalf of:
Septic Service Pro, LLC
Peachtree Street NW
Atlanta, GA 30334
(678) 292-8728

How a Septic Tank Works

Your sewer septic system and tank does not need to be a mystery!

Your septic tank works by allowing waste water to be treated in your yard, basically.  Bacteria work to digest and decompose the solid materials.  Raw sewage never is disposed of in your yard.

In the septic tank itself, chambers are present.  These chambers are where the solids are separated from the waste water.  This solid waste is eaten and broken down by the bacteria, making it take up less space.  Because the solids are compacted, they become heavier and settle to the bottom of the tank.  Any solid material that can not be broken down must be removed from the tank.  If you flush baby diapers, feminine hygiene products, paper towels, cat litter, or other non-human waste into your septic tank, you will need more frequent septic tank pumping. 

Waste water remains at the top of the septic tank, and is eventually distributed out via the drain lines to the leach field or drain field.  This is treated sewage, and is no cause for concern.  However, the area around your septic tank and leach field should never be ‘wet’ or have standing water.  If it does, you should call a local sewer septic professional for immediate inspection.

It is important that you know where your septic tank is located.  Generally, properly installed and operational sewer septic systems require little to no maintenance except for periodic pumping.  Prices for pumping will vary depending on the size of the tank, and the location of your tank.

Why is a Septic Tank Called “Septic”?

The term septic relates to the ability of oxygen to survive in an area.

When you have a self contained, home sewer system, you need a waste water tank.  The average American makes about 50 gallons of waste water daily, from showers and baths, washing dishes and clothing, and using the toilet.  A waste water tank is needed to collect this fluid.  This tank separates the large solids and allows for decomposition.  A soil filter helps remove the small or fine solids, and natural processes destroy the bacteria.

A septic tank is a tank that is anaerobic, meaning that it does not need air or oxygen intake.  Another type of waste water tank is called an aerobic tank  The aerobic tank actually uses an air agitator to help dissolve the solid wastes.

Bacteria are the reason the solids are dissolved.  These digestive processes release a gas.  If you have a septic tank that is ‘smelly’, that means an air leak has occurred, and you need to call a sewer-septic professional immediately to prevent further damage from occurring.

There are many different types of septic systems.  The most common design for residential homes has a two part system:  the waste water storage and treatment tank (the septic tank) and the drain field or leach field.  The drain field allows drainage of treated effluent to return to the soil.  In no circumstance is untreated or raw sewage ever placed back in the soil in your yard.  The only maintenance required in a properly installed and operating sewer septic system is the regular ‘pumping out’ of the septic tank itself every few years.

Healthy Habits for Septic Systems

Septic systems are an excellent alternative for disposal of wastewater.  Developing a few simple habits will help keep your septic system working great and avoid expensive repairs.

The amount of wastewater and sewage a septic system can handle is limited by the size of the septic system installed.  When a septic system is installed, your sewer-septic professional will determine the proper size of the system based on the anticipated volume of wastewater.  The wastewater flow is generally estimated based on the number of bedrooms they property has and the type of soil where the leach field will be placed.

Minimizing the amount of wastewater flowing from your house will help maximize the service life of your septic system and keep repair and service costs to a minimum.  Installing low flow shower head and toilets and using a high efficiency clothes washer will help minimize wastewater flow.  You can also eliminate the second rinse on your dishwasher and avoid leaving the water running while washing dishes, brushing your teeth, and other such activities.  Not only will you save money on your water bill, you will be extending the life of your septic system.

Take care when choosing cleaning products.  Your septic system relies on naturally occurring bacteria to function properly.  Some cleaning products can be harmful to these desirable bacteria.  If in doubt, consult your sewer-septic professional.

Avoid disposing of garbage, grease, paint and other non-organic materials such as paper towels, feminine hygiene products, baby diapers and wipes, and cat litter and minimize food waste flushed down your drain.  These materials can cause the sludge level in your septic tank to rise and can clog the leach lines. You will need more frequent septic tank pumping service.

Properly maintained and cared for, your septic system will provide years of trouble free service.

Leach Field

Thankfully, homeowners with a septic sewer system no longer have a cess pool, but instead have a modern, safe way to leach the liquid wastes into the ground.  This is known as the drain field or leach field, and it surrounds the septic system providing for drainage of liquids.

The leach field starts with the discharge pipe from the septic tank itself.   This discharge pipe leads to a network of perforated pipes (imagine many different straws with holes in them leaving the septic tank).  These perforated pipes are elevated in a way to optimize the work of the bacteria.  In this way, the solid waste materials are digested in the most efficient manner.

Occasionally problems arise with the leach field.  These are usually caused from the soil becoming clogged and not allowing fluids to seep out into the surrounding area.  Deep roots are often the cause of these problems.  When the leach field is not working properly, sewage will back up in the home, and sinks and toilets will not drain properly.

Caution should be taken about planting any large trees or shrubbery around the septic tank or field.  These root beds often break the perforated pipes, or clog them completely.  Chemicals sold to ‘clean out’ septic tank lines generally are not effective.  When backed up toilets are occurring in a septic sewer system, the best bet is to call a certified septic professional to determine the cause of the problem.

Water Conservation

Septic systems work best when they are not overloaded with too much water.  A few simple steps can help you ensure that water usage is appropriate for your home septic system.  Being conservative with water usage can help extend the life of your septic system, especially the drain lines and the surrounding drain field.

Some tips for easy water conservation:

Make sure that you have no leaking faucets, toilets, shower / bath heads, or other plumbing fixtures.  On a regular basis, check the float valve on your toilet to make sure that water isn’t constantly running.  A little bit of water over the course of a day or week adds up.  Make sure that no water is running when all fixtures are turned off.

Install a water meter to recognize usage patterns.  Water meters are especially helpful if your home size grows (such as when additional adults come to visit long term).

Consider how much water you are using when you do laundry.  Are the loads full?  If not, can you change the setting to accommodate a smaller load?  Low suds detergents tend to use less water in the rinse cycle.  Front loading machines use less water than top loading ones.  If you are reaching maximum capacity for your septic system, consider spacing the wash out over several days, instead of doing it all on one day.

Use water conserving shower heads, and limit the length of showers.  Try to limit the length of time you let the water run to make it hot or cool enough.

Treating water like a valuable resource will help keep your septic system trouble-free for many years.