When planning a garden, you may not think about your septic tank, but maybe you should. More specifically, you need to understand the do’s and don’ts of planting in or around your septic tank soakaway, also known as a soakage trench or drainage field.
First, what is a septic tank soakaway?
A septic tank soakaway is a series of underground, perforated pipes that allow septic tank effluent to soakaway over a large area. Excess nitrogen and phosphorus is removed from the effluent as it is purified by the soil. Plant roots can help your septic tank drain system work better by removing moisture and nutrients which in turn help the soil work more efficiently.
What should you plant over a septic tank soakaway?
Deep roots can damage soakaways, so shallow rooted plants are ideal for this area. A septic tank is generally installed about 0.6 to 0.9 meters underground, meaning you do not want the root systems of your small plants or shrubs to extend below this depth. The best plants to use near drainage fields are flowers, grasses, and small groundcovers that will not grow deep enough to disrupt the pipeline of your septic tank.
While Ri-Industries septic tanks are made from 40 MPa concrete, and the engineer-designed tanks are built to withstand anything, it is not recommended that anything with deep roots, especially trees, are planted near your septic system.
Tips: when planting, do not dig too deep and be sure to wear gloves to protect against bacteria that may be in the soil.
Dense covering, such as a lawn, is recommended over a septic tank soakaway to help prevent soil erosion.
Planting a lawn or garden over the soakaway is a good way to care for it while adding beauty to your landscape.
If you really must have plants near your septic system, speak with your garden specialist to find out the ph of your soil and choose shallow rooted plants suited to that ph level. Otherwise, the simplest answer is to plant a lawn over the soakage trench.