Landscaping Around Your Septic System

The most common type of septic system is a gravity fed system with a drain field, also known as a leach field. The drain field is where effluent, or wastewater, flows from the septic tank through a series of pipes and distribution boxes to be purified and treated naturally by the Earth. This process is vital to the health of any system. Keeping the soil and Earth absorbing the effluent properly can be helped with regular maintenance but can also be helped with proper landscaping choices.

Build away from the drain field
Healthy soil is an essential part to a functioning gravity fed septic system. The complex biological soil community that purifies wastewater is an amazing feature of our Earth. To maintain this function the soil needs to be aerobic (with air). Building structures on top of the drain field can disrupt this process while also putting too much pressure on the drain field. In addition to a potential drain field failure from a structure, fixing issues or replacing a drain field can become difficult or impossible if there is a temporary or permanent structure on top of this part of your system.

Keep sprinklers away
There are many different soil types and each septic system is designed to work with the soil around it. Ideal soil will take in the wastewater, purify it as it enters the ground and the water will return to the underlying groundwater or will be absorbed by nearby plants. When there is too much water in the soil a drain field can become oversaturated. The soil will not be able to purify the wastewater effectively and wastewater will puddle at the top of the ground. This leaves a septic system owner’s yard contaminated with pathogenic bacteria or viruses. It’s best to divert sprinklers at least 10 feet from the drain field. Diverting all surface drainage away from the septic system is also recommended. If you struggle with ground water saturation, contact your local service provider for diversion options.

Avoid deep-rooted and water-loving plants
Planting a mix of grass and existing native plants with shallow roots is the best way to go for drain field coverage. While every geographical area will be different in the variety of ground coverage, anything that needs a lot of water or has long roots can infiltrate the pipes and distribution boxes of a septic system causing clogs and breakage. Additionally, adding gravel, bark or other fill over the drain field can disrupt the soil’s process and may harm your system. Only the addition a very thin layer of topsoil is ever okay.
Never plant vegetable gardens on or near a drain field. Water from your toilets and kitchen sink is considered blackwater, as it contains raw food particles. This type of wastewater is best kept away from any plants you plan on ingesting. However, in some drought-stricken areas they use greywater systems that divert water from laundry machines and showers. This greywater can be used to water vegetable gardens. Contact your local preferred septic system installer for information on greywater systems.

Grass and native shallow-root plants are best

Your drain field is a complex biological environment that needs it’s own space to purify wastewater. Keep from overwatering and building on top of the system to help it treat effluent efficiently. Keep landscaping to a minimum in the drain field area to help the system avoid clogs and root infiltration. If you have any questions about landscaping around your system, call a local septic system specialist first.

This article was originally published in January 2016 by Speedy Septic on the Angie’s List Experts Blog.