Landscaping Your Drainfield

On-site sewage systems and drainfields are an important investment. Proper planning and landscaping of your drainfield area can save lots of time, work and money. It is important to know the location of the drainfield before doing any landscaping, gardening or construction work.

Things to avoid in your drainfield area:

  • Do not use solid materials such as concrete or plastic, as they reduce evaporation and the supply of oxygen to the soil.
  • Do not allow traffic such as vehicles, heavy equipment and livestock. The pressure can compact the soil and also damage pipes.
  • Do not plant deep-rooted plants. These tend to invade and damage drain pipes.
  • Do not water your drainfield area. Excess water reduces the soil's ability to treat wastewater.
  • Do not Rototill your drainfield area. It can damage your distribution pipes.
  • Growing vegetables over a drainfield is not recommended.

And now, for some positive options for landscaping your drainfield area…

Landscaping FlowersGrasses are good plants to grow over your drainfield. Grasses do not always need to be mowed, they help stabilize the soil, and also provide food and cover for small birds. By mixing with shallow rooting native flowers, you can create a prairie or meadow. Festrica (fescue) grasses are better suited for areas under or near trees.

It is important that the plants you put over your drainfield have shallow roots and do not need too much watering.

The Clallam County Cooperative Extension Office can also provide more ideas for landscaping your drainfield. They have given Environmental Health permission to publish their handout about Drainfield Landscaping (PDF) on this website.  Other WSU Extension offices have various publications with additional details about landscaping your drainfield that can be found at Spokcane County Extension and Clark County Extension

Tips about the landscaping of OSCAR drip irrigation drainfields (PDF) are provided by the manufacturer, Lowridgetech Onsite Technologies, LLC.