Do Water Softeners Harm Septic Tanks?
The concern over the potential impact of water softeners on septic tanks is a topic of much debate. Popular opinion suggests that it is not the soft water itself, but rather the salt from the water softener's backwash process that can harm septic tanks and affect the drainfield. However, the reality is often more nuanced and dependent on the correct setup and operation of the systems.
Understanding the Impact of Salt Backwash
Water softeners use salt during their regeneration process, which produces a brine that is flushed back into the sewage system. This brine is a significant source of sodium, which can accumulate in the septic tank and drainfield over time. In most cases, the concentration of salt in the water from a properly functioning water softener is not a significant issue. However, if not managed correctly, salt backwash can indeed cause harm.
For instance, in a town of 35,000 people, the salt content from water softeners can lead to a substantial buildup. Over a year, water softeners can use approximately 10,000 gallons of water per cycle, depositing around 150 gallons each time, resulting in over 500 pounds of salt being flushed through the septic tank and into the leach field. This can impact nearby vegetation and even contaminate the aquifer from which drinking water is extracted. The cumulative effect of this ongoing influx of salt can lead to significant issues in residential areas, as the example in a town of 35,000 illustrates.
Effects of Salt on Septic Systems
When saltwater is introduced into the system, it sinks to the bottom of the septic tank and acts as a kind of mixmaster, displacing the sludge and forcing undigested effluent into the leach field, potentially clogging it. Salt is also highly corrosive to pipes and the concrete septic tank. In severe cases, older tanks may develop holes, compromising the tank's integrity. Furthermore, the active ionic components of salt can react with other dissolved solids, cleaners, oils, and fats, causing them to precipitate out and fill up the tank, leading to reduced capacity and increased risk of overflow.
My own experience supports the use of alternative water treatment methods, such as filtration and reverse osmosis (RO) water, combined with the use of easily biodegradable products. This approach has enabled a 1,000-gallon septic system to serve a household of four people for over 42 years without needing to be pumped out. This scenario demonstrates that with proper management and the right practices, water softeners do not necessarily harm septic tanks.
Addressing Concerns about Water Softener Impact
It is true that during the backwash cycle, the removal of salt from the water softener can introduce a significant amount of salt into the septic tank, which can negatively impact the bacteria necessary for the biological treatment process. This can, in turn, cause the septic tank to become overwhelmed and necessitate more frequent pumping.
Additionally, the products used during washing clothes can contain chemicals that are harmful to septic systems. At least twice a year, introducing a package of yeast down the toilet can help replenish the beneficial bacteria needed to maintain the system's functionality and reduce the need for frequent pumping.
One way to mitigate the impact of water softeners on septic tanks is to ensure that the water softener is properly set up and maintained. Regular servicing and calibration of the water softener can help prevent excessive salt from being released into the sewage system.
In conclusion, while there is a potential for water softeners to harm septic tanks and drainfields, this risk can be greatly reduced by proper management and maintenance. By using alternative water treatment solutions and employing gentle cleaning products, it is possible to maintain a healthy septic system even if a water softener is in use.