What Happens To Your Septic System During Heavy Rain?

If you have a conventional septic system, heavy rainfall that comes with floods can make the system to lớn stop working. As rainwater floods over your drain field, the effluent from the septic tank will have sầu no place khổng lồ drain because the ground under the drain field is already saturated with water. This will make the septic waste to start backing up in the house and to lớn overflow on the lawn.

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In a conventional system, the septic tank holds wastewater for 2-3 days as the anaerobic bacteria treat it. When the effluent leaves the tank & drains into lớn the leach field, the partially treated water percolates through the gravel and inlớn the sand via perforated pipes in the drain field. As the water passes through the gravel in the leach field, pathogens are removed by aerobic bacteria before the water goes baông chồng inlớn the groundwater. If the leach field gets saturated, the partially treated water from the septic tank doesn’t go through the final treatment process in the drain field. As a consequence, the wastewater will baông chồng up in the tank và overflow in the leachfield.

Signs of a flooded drain field

If you are experiencing heavy rainfall in your area, it is best khổng lồ be on the lookout for any tale-tell signs of a flooding drain field. Here are some of the signs;

Sluggish drains in the houseToilets draining slowly when flushedGurgling sounds in toilet and drainsBacking up of water inlớn the floor drains và basement

Septic systems are designed to only handle wastewater from the house. In fact, the kích thước of the septic tank installed on a property is determined by the occupancy of the house (number of bedrooms). If runoff water from the storm gets inlớn the septic tank, it will get full and since the soil in the leachfield will be already too saturated, the water will start backing up inkhổng lồ the house or from the manhole.

Maintaining the septic system BEFORE the heavy rains

It is possible for your septic system to lớn withst& heavy rainfall but it needs to lớn be well maintained. For this reason, you should always pump your septic tank on schedule và you should ensure it is working efficiently throughout the year. The septic tank relies on anaerobic bacteria in order to liquefy the waste so it is in your best interest to ensure the bacteria in the tank are as healthy as possible. First and foremost, you must desist from using any toxic substances that might kill the helpful bacteria lượt thích scented soaps, antibacterial soaps, paint, etc. But since it is not possible to lớn totally avoid getting harmful substances in the septic tank, adding biological additives can help. The additives introduce billions of enzymes và bacteria inlớn the septic tank which helps the septic tank to regain its efficiency.

What to vày if the weather forecast warns of a looming storm

If the weather forecast has warned of an impending flood, take these precautionary measures in advance to lớn help safeguard your system;

Seal any possible points of entry into the septic system.Seal of all inspection points lớn ensure the excess rainwater will not find its way inlớn the tank.Switch the pump off at the circuit box before the area gets flooded in water.Cut off the power supply to the pump in the lift station of your mound system if you have one. You can also remove the pump from the system in order lớn protect it from damage.Waterproof any electrical connection in the system in order lớn safeguard electrical wiring from getting damaged và also to lớn avoid getting shocked.

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Maintaining the septic system DURING the heavy rains

Once the heavy rains start, it is advisable khổng lồ avoid any non-essential usage of water. The idea is khổng lồ avoid straining the system even more than it already is. For instance, flush the nhà wc only when necessary và reduce the number or duration of showers. If the drain field gets flooded, you should stop using the nhà wc & faucets altogether. A flooded drain field means the system is already blocked so you vày not want to make the bad situation even worse. Additionally, avoid liên hệ with any flooded water because there is a good chance the water is contaminated.

Maintaining the septic system AFTER the heavy rains

Do not attempt to have the septic tank pumped before the floods rescind. Pumping the tank in the midst of floods could make the tank float out of the ground và cause serious damage to lớn the entire system. The thing to rethành viên is, the problem is not actually the septic tank but the saturated soil in the drain field. the best cause of action is to quit using the system altogether until the flooded water recedes và the soil around the drain field area dries out. Here are some tips khổng lồ help you limit the water that is going into the septic tank.

Do not sover the basement sump pump water into the septic tankReroute any rainwater from your roof gutters away from the drain fieldStop using the garbage disposal và dishwasherReduce the number & duration of showers và if possible, take sponge bathsDo not run water while brushing your teethWash your clothes at a laundromat

Sometimes, the backup is a bigger problem than stormwater – it could be caused by a clogged up drainfield. If organic waste leaves the septic tank prematurely, it could kết thúc up clogging the drainfield thereby causing backups.In such a scenario, pumping will not fix the problem because after pumping it, the tank will fill up again in no time. The best approach would be lớn clear the clog through shoông xã treatment. Shoông xã treatment is the introduction of biological additives that are made from bacteria và enzymes. These biological additives introduce billions of bacteria inkhổng lồ the septic system which liquefying the organic waste thereby unclogging the system.

Safety precautions after a heavy downpour

If the floods were really serious, you might have sầu to temporarily evacuate the house. If evacuation becomes necessary, vì chưng not move baông chồng in before you check with the authorities khổng lồ ensure all advisories have been lifted. Here are other important safety tips khổng lồ observe;

Do not attempt lớn dig around the drain field area when the soil is still wet. Avoid working with heavy machinery over the drainfield too because it can cause compaction of soil which will then make it hard for aerobic bacteria in the drainfield lớn get enough oxyren.The scum layer in the septic tank could have lifted up and blocked the outlet. You should, therefore, kiểm tra the outlet tee when the flooding stops to lớn ensure it is not blocked.Do not handle any of the electrical devices that are part of the system until they have completely dried.Upflow filters, truyền thông media filters, aerobic plant, and other such components of advanced systems could get blocked by mud và debris from the floods. You should, therefore, wash these systems thoroughly before putting them baông xã lớn use.


As long as you take good care of the system before the flood arrives, it should weather the storm just fine. That said, there are some storms that are just too rough for any system to lớn handle especially if you continue using the water like you usually vì. If this is the case, then you might want to lớn Call a professional khổng lồ inspect the system và help you in repairing any damage that might have sầu been done. Otherwise, just follow the tips shared above & you will be fine.