How to Properly Plan and Maintain a Drain Field

a sewage drain field
What You'll Need
Scaled design blueprint
Border material (to block off the area)
Gutters or run off system
Shallow rooting plants or grass

A drain field, or leach field, is the area into which a septic system drains. It is composed of a series of pipes, and material such as gravel and soil. The field works to remove material from the septic system and then to remove the contaminants. There are several things to keep in mind to keep your drain field functioning as it should.

1. Design

blueprint with tools and hardhat

Hiring an engineer to design and implement the drain field is the best way to go. This will ensure that the field meets all local regulations, and will prevent common design flaws. The size of the drain field needed will depend on the percolation rate of the soil and the size of the home. If the soil is poor, it could take as much as 9,000 square feet for the absorption area. This is why an engineer will be best suited to the job. They can test the soil and plan a field accordingly.

2. Block it Off

It's important to know where your drain field is placed. If it's possible to create a barrier, this should be done. Heavy weights, such as that from cars, livestock or other heavy equipment, can crack the pipes used in the field. You also don't want to build anything on top of the drain field. Patios, gazebos, and carports should be built in other areas. Paving over the field can also damage the function, since it will block vital oxygen. Many people will plant gardens over their drain field. While this a good use of the space, you should only use plants that have shallow roots. Trees and shrubs should be kept at least 30 feet away. This will protect the pipes from the rooting that happens with trees and larger shrubs. Shallow plants and grasses will also help prevent soil erosion.

3. Water Runoff

You may need to reorient drainage ditches and gutter systems. Water that is allowed to run into the drain field will saturate the soil, making it weaker and leaving the pipes open to damage. Most engineers suggest creating a separate drain off route for heavy rains as well to help prevent the field from becoming overly saturated.

4. Know How to Identify a Problem

underground pipe spraying water

Septic systems are generally easy to take care of. The first sign of a problem will typically occur in the drain field, so it's important to know what to look for before the problems get out of hand. If you see wet spots in the field, it needs to be checked out. This can be from a system that isn't flowing downward as it should. If this is taken care of, you will start to see sewage surfacing. If you have well water, you should test for the presence of bacteria a few times a year. A drain field that is backing up can often lead to coliform in the water of the well. Any foul odors also signal a problem with the drain field. If any of this has occurred, it's time to call in a professional.