Rain and Your Septic System

Heavy rain can cause serious problems for your septic system, especially if you don’t know what to look for. Minnesota can have significant rain events, from slow, steady, and constant rain to flash flooding. As you are looking at maintaining your septic system all year long, you should pay attention to the weather and look for signs of rain negatively impacting your septic’s performance.

Heavy, sustained rains or flash flooding events can cause issues to your septic. Your septic’s drainfield is the most susceptible to issues during rain events because it is directly impacted by the elements. So as you take care of your septic, here are some things to look for. 


Liquid waste is meant to flow into your septic system’s drainfield where it can be recycled to become purified water for the surrounding soil. If your drainfields are clogged, rainwater can overwhelm the drainfield and make the absorption of wastewater impossible. Once wastewater cannot be absorbed properly, it keeps your septic from doing its job. Pipes will gurgle. Smells will linger. Drains will slow.


Septic systems take in the wastewater from your home (laundry, sinks, toilets, etc.). If rainwater mixes in or merges with your wastewater, you can easily and quickly overload your septic. It will fill up and back up into your drains.


An overly saturated drainfield can keep the drainfield from purifying water for the surrounding soil. If too much rain is impacting your septic system and drainfield, your drainfield may not be able to purify the liquid waste that the septic system is releasing. This can cause contaminated water to stay not just in your drainfield, but can cause it to be released into nearby streams, lakes, and drinking water sources.

You can’t always predict the weather or stop the negative impacts of it on your septic system. What you can do, however, is keep high standards for septic care. Keep water from draining toward your septic’s drainfield. Make sure you’re paying attention to what you’re flushing down the toilet or washing down your drains. And partner with a septic care company like Septic Check. We will help you make the right decisions to protect your septic…and your home or cabin!