A.Jennifer Hause responds: For the most part, there are few problems with septic systems associated with the use of low-flow fixtures. While it’s true the wastewater is more concentrated, the increase in pollutants will likely be insignificant in existing septic systems that were sized for older fixtures ( problems only arise when you get a flow reduction of 20% or more for a given amount of effluent).
More often, the use of low-flow fixtures is a benefit to a septic system because it helps reduce the size of the drain field and reduces "hydraulic overloading" of septic tanks. Excessive amounts of water in the system, typically from laundry, toilet flushing, and bathwater, commonly cause undersized septic tanks to overflow, sending solids and...
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