Leach Field Design

Leach Field
Septic systems are crucial systems for treating wastewater in rural locations, and leach fields are a key part of the septic system. Septic systems are necessary for places that are not connected to a wastewater treatment facility or a sewer system. Leach fields, also known as drain fields, are where the liquid wastewater from your septic systems drains out underground into your yard or property. Leach fields require certain maintenance and must be cared for properly not to contaminate your groundwater or your land. Leach fields are needed for removing impurities from your wastewater after the water and sludge have separated in the septic tank, and the wastewater has exited the septic tank.

Leach fields should be located in an area free of roots and not obstructed by anything else on your property. You must be careful not to plant trees or bushes close to the leach fields for maintenance of leach fields. If roots become entangled in the leach field pipes, it can cause issues. Trees and bushes must be planted at least ten feet away from the boundary of the leach field. Leach fields should never be driven over, and you must be careful not to build anything on top of them. Leach fields should never be seen or noticed from above ground. If you are to see puddles or an overly lush area on the surface level of your property, your septic tank may be excessively full, and the sludge from your septic tank will need to be drained by a professional. Septic tanks should be pumped yearly to avoid large build-ups of solid material. If there is too much solid material in your septic tank, it can flow through the drains and make its way to the leach field. Leach fields are not meant to handle solid waste, and this should always be avoided.

Leach Field Design
Leach fields are necessary when a septic system is present, and there is no need for greywater or wastewater reuse. Leach fields are designed to allow the wastewater to exit from the septic tank into pipes perforated so that the liquid drains out of the pipes and into the soil. Depending on the soil type, the wastewater will percolate through the soil differently. After some breakdown has taken place in the septic system, the remaining wastewater flows in pipes out to the waste field. Wastewater is leached into the soil so that the wastewater can be filtered naturally by the soil. As wastewater is perforated through the pipes in the leach field, the wastewater is absorbed by the soil, and the water moves through the soil vertically and horizontally through soil pores. Bacteria that live within the top ten feet of the soil remove the organic material that has been dissolved into the wastewater. Some of the wastewater move up the soil and evaporate. Plants can absorb some of the wastewater that does not percolate all the way through the soil. The remaining wastewater percolating into the leach field eventually reaches a groundwater aquifer with the intent that the water has moved through enough soil and the soil has cleaned up the water not to contaminate the groundwater.

Leach field size is dependent on the size of the home and how big of a septic system they have. There is a few different setups for leach fields: dry well systems, mound drain systems, and chamber systems.

Dry Well System
The dry well system uses gravel and perforated pipes spaced out for proper drainage. The trenches for the pipes have gravel, and they should be four to eight feet underground. The trenches for the pipes can be as long as a hundred feet, and typically, a trench is one to three feet wide. Each trench is separated with six feet between. The dry well system is durable and reliable but sometimes seen as less effective for filtering the wastewater because it has a reduced surface area.

Mound Drain System
Mound drain systems are used when you cannot build your leach field into the ground because of soil type or other ground conditions. Mound systems are built above ground and require a pump to transfer the wastewater out of the septic system to the above-ground system. The water pumped over the mound drain system percolates through the soil in the mound, and the soil cleanses the water as it would in the typical dry well system. These systems may not be as durable as the dry well system but can be maintained by good construction and the correct soil type.

Chamber System
Chamber systems are used when there is no gravel available to make a gravel bed below the pipes. This system has a lower installation cost than the other options but can be a high maintenance option needing to be monitored often to make sure they do not leak or overflow. They are built in the drain field as a plastic chamber that holds the wastewater fluid, and the containers allow the wastewater to slowly seep below into the soil.

Leach fields are a crucial part of the septic system. Septic systems are needed in rural areas that do not have access to sewer systems or wastewater treatment plants. These systems must be monitored and taken care of properly, or they can cause environmental hazards and can have devastating adverse effects on the water table. There are many different ways to keep your leach field safe, including not planting trees near the leach field and being careful and monitoring the surface of the leach field. Wastewater is treated through the soil after it leaves the septic tank and before reaching the groundwater table. There are three different leach field designs: the dry well system, the mound drain system, and the chamber system. Each design has benefits and can be effective for cleaning and dispersing wastewater from your home and into your yard. With proper maintenance and construction, a leach field can remain safe and is important for removing wastewater.