Caring for your Septic System

Are you the owner of a septic system?

If so, your septic system can provide effective, long-term wastewater treatment, right in your backyard. If your system is working properly, it is an environmentally friendly and economically sound treatment option.

Out of sight – out of mind?

Unfortunately septic systems are out of sight. Many homeowners don’t realize that there may be a problem until their system is already failing. It is estimated that up to 20 per cent of septic systems in our region are malfunctioning. The most common cause of failure is lack of maintenance.

How does my septic system work?

Wastewater from your sinks, toilets and laundry drains through a pipe from your home into your septic tank. Your septic tank is designed to hold the wastewater long enough to allow solids to settle at the bottom and oil and grease to float to the top.


Signs of Septic System Failure     

It is time to call a professional if you notice any of the following:

  • Slowly draining sinks and toilets
  • Gurgling sounds in the plumbing
  • Unpleasant odours around your property
  • Patches of lush growth over the drainfield
  • Soggy or wet ground over the drainfield
  • Sewage surfacing

Natural bacteria in the tank start breaking down the solids; however, eventually the solids build up and must be pumped out. Regular pumping will reduce the amount of solids entering your drainfield and ensure proper drainage and treatment.

The partially treated wastewater from your tank flows through an outlet into a distribution box. The box evenly distributes the discharged wastewater into a network of pipes underneath the drainfield. The wastewater begins to percolate into the soil through small holes in the pipes. Natural filtration and microorganisms in the soil remove any remaining harmful particles in the wastewater. The treated and cleansed wastewater passes into the groundwater and returns to the water cycle.


Why should I care for my septic system?     

There are three main reasons for maintaining your septic system:

  • Save money. A failing septic system can be expensive to repair or replace. You can protect yourself against costly surprises through regular preventative actions like inspections and pump-outs of your system and by learning the do’s and don’ts of septic care.
  • Protect the health of your family. A failing septic system can release inadequately treated household wastewater and offensive odours, often right in your backyard. Human wastewater contains disease causing organisms and can pose health risks to your family and your neighbours.
  • Protect water quality. We all depend on clean water. A septic system uses the environment to treat wastewater but may release untreated or partially treated wastewater if the system fails. Inadequately treated wastewater can pollute our creeks, lakes, shorelines and groundwater and can contribute to shellfish bed closures and contaminated drinking water supplies.

How do I care for my septic system?

Your actions are the key to your system’s longevity. Here are ten steps you can take to maintain your system:

  • Locate your septic tank and drainfield. You will be prepared if there is a problem.
  • Check the operation of your system annually. Look for signs of failure.
  • Have your septic tank pumped regularly. Health authorities recommend pumping every three to five years. Combine the pump-out with a professional inspection.
  • If you have a package treatment plant, set up a contract for annual maintenance.
  • Make sure your system has an effluent filter to reduce the amount of solids entering your drainfield.
  • Keep a running maintenance record.
  • Reduce your water consumption. Too much water use will flush solids into your drainfield rather than have them settle in the tank.
  • Use environmentally friendly cleaning products. Some chemicals can upset the proper balance of bacteria needed to provide primary treatment inside your tank.
  • Recycle or properly dispose of hazardous products. Do not pour them down the drain or put them in the garbage.
  • Protect your drainfield by leaving it as undisturbed as possible. Do not drive or park on it. Landscape with grass rather than plants with roots that can damage your system.

Protect your Drainfield     

The drainfield includes the pipes that discharge your wastewater as well as the soil beneath those pipes that receives and further treats the wastewater. The drainfield is the most complicated and expensive part of the septic system to repair or replace – it is a substantial investment. Treating it right and protecting it from damage can save considerable money and protect water quality and your family’s health.

Remember to maintain easy access to your tank and drainfield at all times for regular inspection and pumping.

  • What can I plant over my drainfield? Grass is the ideal cover for drainfields. If your tank covers are buried, keep in mind that plantings over the tank – from inlet to outlet – will have to be removed every three to five years for inspection and pumping.
  • Can I plant trees and shrubs near my drainfield? Trees and shrubs generally have extensive root systems that seek out and grow into wet areas such as drainfields. If you do plan to plant trees near a drainfield, consult an expert to discuss your ideas and needs.
  • Can I plant a vegetable garden over my drainfield? No. Growing vegetables over a drainfield is not recommended. Vegetables need watering and excess water in the soil reduces its ability to treat wastewater. The deep roots of some vegetables may damage drainfield pipes. Bed preparation, such as rototilling or deep digging, can also damage pipes.
  • What about landscape plastic or fabric under mulch? No. Plastic reduces the necessary air exchange in the drainfield soil. Even mulch or bark over the drainfield is not recommended because it reduces air exchange and retains water.
  • Can I build a carport or camper pad over the drainfield? How about a tennis court or a hot tub? No, for two reasons. First, you should avoid driving over the drainfield. The pressure of vehicles and heavy equipment compact the soil and can damage pipes. Second, impermeable materials such as concrete and asphalt reduce evaporation and the supply of oxygen to the soil. Oxygen is critical to the proper breakdown of sewage by soil microorganisms.
  • How about putting my carport over the replacement area? No. The designated drainfield replacement area (reserve area) should be left undeveloped and protected from compaction. It should be treated with the same care as your drainfield.
  • Livestock must be kept off drainfields. In the winter, livestock trample and muddy the soil; in the summer they compact it. Again, this is not good for the soil’s ability to exchange oxygen. Even a dog kennel or confinement area should not be sited over the drainfield.
  • Rain water is directed onto my drainfield. Is this a problem? Yes. Extra water will saturate the soil and prevent the drainfield from treating wastewater properly. Downspouts and stormwater from surfaces such as driveways and patios should be diverted away from the septic tank and drainfield. A small trench uphill from a drainfield can help direct water away.
  • How close to the drainfield can I install a sprinkler system? Water lines should be at least 10 feet from all components of the septic system. Be sure all sprinkler lines are fitted with approved backflow prevention devices and check them annually for leaks.
  • How does an effluent filter protect my drainfield? An effluent filter fits securely in your outlet T and is highly effective at keeping solids out of the drainfield. It forces the wastewater to pass through small holes before entering the drainfield and keeps solids inside the septic tank where they can be pumped out. They range in price from $75 to $150 and are well worth it.
  • My roof gutters are connected to my septic system. Is this ok? No. “Clean water” wastes, such as footing drains, roof drains, water softeners, or dehumidifiers do not need to be connected to the septic system they only add excess water. Water conservation should be practiced in order to minimize the flow of water through the drainfield.

How does the soil treat wastewater?     

  1. The soil filters out particles that make wastewater appear cloudy
  2. Organic matter is removed as it is a food source for microorganisms living in the soil
  3. Disease-causing bacteria are filtered out of the wastewater by the soil and once trapped, either die in this hostile environment or become a source of food for microorganisms.
  4. Viruses are chemically attracted to soil particles which removes them from the wastewater.

For more information please visit the following web sites:

BC Onsite Sewage Association

Ministry of Health Services

Note: The information on this web page is taken from a brochure published by the Capital Regional District (CRD), Vancouver Island. Visit their excellent website for more information on this and related subjects.