How to Construct a Washing Machine Drain Field

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Things You'll Need

  • Perforated drain pipe

  • Shovel

  • Gravel or other small rocks


Avoid putting the drain field in areas where water pools during rainy season.


Make sure your drain field is not near any trees as roots can interfere with drainage.

Most county code ordinances require a washer to drain into the septic tank. However, when there is a shortage of water, it only makes sense to reuse and recycle the water draining from the washer. While it is not advisable to place the drain field near a vegetable garden, it works great when placed near a flower garden. However, do not place it too close to the plants since the chemicals in the washer water could leach into the plants and kill the plants.

Step 1

Determine where the drain field will be placed. It should be at least 3 feet away from any plants to avoid the chemicals in the used water from damaging the plants. The drain field should be at least 2 to 5 feet from the exterior of the home.

Step 2

Using the shovel, dig the drain field. The hole should be 2 feet wide, 4 to 6 feet deep and approximately 20 feet long. For families with five or more members, the drain field should be a minimum of 25 feet long due to the large amount of laundry done in large families.

Step 3

Place a layer of gravel 2 feet thick along the bottom of the drain field. A 1- to 2-inch layer of straw or sand should be placed on top of the gravel to prevent particles of waste from the water getting into the gravel and providing an environment conducive to growing bacteria.

Step 4

Place a 20-foot-long perforated drain pipe into the drain field hole. Cover the perforated drain pipe with gravel around the sides and on top of the drain pipe. Attach the washing machine drain pipe to the perforated drain pipe. Be sure that the pipes fit into each other to prevent washer water from leaking onto the ground at the connection point of the two pipes.

Step 5

Refill the drain field with dirt. About 2 weeks after the drain field has been installed, go back and put more dirt on the drain field since some of the dirt may have settled and caused a canal that can fill up with water when it rains and thereby reduce the ability of the drain field to properly drain the washer water.


Katherine Bostick

Katherine Bostick has been writing since 1993. She is a freelance writer and has written articles for both the "Spectator" and the "Crossties" newspapers. Bostick writes articles on educational topics, personal essays, health topics, current events and more. Bostick performs copy-editing and book-review services and produces her own local newspaper in South Florida.