The biggest question I get as a septic system professional is how long do drain fields last? The usual focus of septic systems is the septic tank. There is a big reason for this because the septic tank is the receptacle for the wastewater that the household produces. It is the first step to the entire wastewater treatment. Here, the anaerobic bacteria do all the work in breaking down the solid waste particles before the pre-treated effluent makes its way into the drain field. Lately, the drain field receives the equal amount of attention as the septic tank. This is the last phase of the wastewater treatment. Whatever happens in the septic tank affects the drain field. Because of this, a question creeps into your head… how long do drain fields last?
It is no secret that drain fields receive as much torture as it could. Think about it. The drain field surrounds the septic tank and makes up most of the yard space. It takes the pressures brought about trampling and playing; it receives all the rain water and snow; it’s often penetrated by hardwood roots; and it also gets whatever condition of effluent from the septic tank. Basically, if there is a malfunction in the septic tank, it is inevitable for the drain field to fail as well.
Drain fields are not built similarly. Their designs vary because of their location and their soil percolation rate. There are those that are in the existing properties and are dug up to put the needed trenches. Some are raised and are built with sturdy drainage materials. These drain fields are above the ground so that proper absorption and evaporation of the effluent could take place.
Because of the fact that drain fields do vary in structure, they also differ in lifespan. Their longevity depends on the actual size, manner of use, and percolation rate of the soil it is installed in. If the size of the drain field and its septic tank; if the soil is in good condition; if the septic tank is well maintained; and if the pumping schedule is met, then the drain field could last for at least 50 years. But there are cases of drain fields that immediately fail within 24 hours. The reason behind this is the poor pipe installation. There are even conventionally designed raised bed or drain fields that lasted for 20 years.
If the septic tank has anaerobic bacteria, the drain field has aerobic bacteria. The aerobic bacteria in the drain field are responsible for regulating the bio-mat that filters and purifies the outgoing effluent. The drain field should only have short grass planted on it so that the sun’s rays could easily penetrate the top soil and cause immediate evaporation of the effluent. The drier the top soil, the more aerobic bacteria that reside in it, the better the drain field or the septic system functions. Once the drain field becomes soggy, the aerobic bacteria die off and the bio-mat becomes too thick that it already clogs the entire drain field. This results to the failure of the entire septic system.
You can care for the drain field the same way you care for the septic tank. Everything starts in the household. First, consider using bacteria-friendly and environment-friendly household cleaners. This would assure you that the resident bacteria in the septic system would not perish and get killed off. The bacterial population in the septic tank and in the drain field is essential for the smooth run of the entire septic system. You could also stop considering the drains, sinks, and toilets as trash bins. A dry well could be installed to take care of the grey water and lessen the water load of the septic tank. You could also divert the rain gutter away from the septic system and make sure that the system is not run over by vehicles or is under any form of construction.
How long do drain fields last? Homeowners are advised to set aside a budget for the replacement of their drain field that can surely happen at any given time. The main thing that you have to remember is that if the septic tank is well-cared for. The drain field would surely function well.