What Structures Can You Put Over a Drainfield
March 18, 2024 |
In the North, particularly within New England states, there is a high percentage of households on septic systems. New Hampshire and Maine stand out, with approximately 50% of homes relying on individual septic systems.
In this region which reaches all the way down into Maryland and Delaware, drainfield systems often weather colder temperatures, including periods of heavy snowfall. Given the frosty conditions, these systems are typically designed to lie deep enough to prevent freezing.
Three common types of drainfields typically found in the North include:
The type of septic system drainfield you have on your property will largely depend on the level of your property's groundwater and soil type. If you are unsure what kind of drainfield you have, contact Wind River Environmental to schedule a professional inspection.
Drainfields (or leachfields), an essential component of septic systems, serve the critical function of filtering and removing contaminants from the wastewater that emerges from the septic tank. This process occurs as the wastewater percolates through the soil in the drainfield, where soil particles, bacteria, and microorganisms naturally treat the water before it eventually reenters the groundwater system.
For a drainfield to operate effectively, it must remain clear of obstructions and heavy structures. Overloading a drainfield with heavy construction or impermeable materials can compact the soil or block the flow of wastewater, preventing proper filtration. Additionally, covered structures can impede the drainfield from receiving the oxygen it needs to function correctly. This can lead to system failure, environmental contamination, and potentially costly repairs.
Things that should not be installed on top of your septic drain field include:
Things that should not be installed on top of your septic drain field include:
Maintaining a properly functioning drainfield is not only essential for the performance of a septic system but also for protecting water quality in the surrounding environment.
In general, the EPA discourages building on septic drainfields, but there are a few things you can do that are generally considered safe. These can include open-air kennels for pets, lightweight swing sets, or small volleyball or badminton nets.
When considering installations over your drainfield, you must think about the following:
The type of soil present in your drainfield area profoundly impacts the effectiveness and functionality of your septic system. Soil acts as a natural filter, removing contaminants from wastewater as it percolates through the layers and returns to the groundwater system.
Loamy soil, a balanced mixture of sand, silt, and clay, offers the optimal permeability for efficient wastewater treatment and filtration.
Different soil types have varying permeability rates, determining how quickly or slowly the wastewater will move through the soil. For instance, sandy soils allow for quick water movement, which might not allow proper filtration. In contrast, clay soils retain water for longer, potentially leading to saturation and system failure.
Soil types commonly found in the Southeast that are problematic for a septic drainfield include:
Areas with shallow groundwater, which are very wet, or where rock is too close to the soil's surface are also not conducive to the safe operation of a conventional septic drainfield.
Though over a third of homes in the Southeast rely on septic systems, the varied soil conditions across the region (400+ types of soil in North Carolina alone!) mean that many areas cannot rely on conventional septic drainfield constructions. Nonetheless, innovative strategies such as adjusting drainfields closer to the surface or employing artificial drainage techniques ensure the proper management of wastewater.
Common drainfield modifications used in areas with poor soil conditions include the following:
The choice of what can or cannot be installed over a drainfield is significantly influenced by soil type, particularly in the Southeast, where building over your drainfield is largely discouraged. In this region, the primary concern with installing structures over a drainfield is soil compaction.
As previously mentioned, soil's ability to filter and absorb water efficiently is significantly reduced when soil becomes compacted. This can lead to system failure, as the wastewater will not percolate properly, causing backups and potential health hazards.
In the Southeast, where the soil types vary dramatically and rising groundwater is becoming an issue, the risk of compaction from installing structures (or driving heavy equipment) over a drainfield becomes even more pronounced.
You should never install the following over a drainfield:
Even the installation of lighter structures, such as decks or pergolas, should be carefully considered and generally avoided to prevent compaction and preserve the operational integrity of your drainfield.
Before installing anything on your drainfield, always consult with a septic professional, like Wind River Environmental, and your local building codes to ensure that you are not installing something that will damage your septic system or cause environmental damage.
Knowing what structures can be safely placed above a drainfield is vital to maintaining a functional septic system. Always confirm with local guidelines and our septic system professionals before changing your drainfield area. Regarding the safe operation of your septic drainfield, you are always better off being cautious and consulting with septic system specialists like our team at Wind River Environmental.
Contact us online today to schedule an appointment and learn more about your septic drainfield and how the area it occupies can be safely utilized.