Local councils around Australia are now asking land and property owners to add a retention tank along with rainwater tanks. While rainwater tanks help in storing rainwater for household purposes, a retention tank prevents ground water contamination and silt inflow and is a useful addition to the standard rainwater tank.
How do they work
A retention tank can be divided into two portions. The bottom half of the tank functions as storage half, and stores rainwater. When a storm occurs, the retention tank fills up and the previously stored rainwater is discharged from an outlet in the upper half, while the fresh storm water is retained in the bottom half.
Why is a retention tank important?
Storm water can carry with it many contaminants like oil, trash, and silt from soil-erosion. Concrete structures hamper the normal path of storm water and a heavy surge of water can overwhelm man- made storm water drains and cause overflow.
The storm water run-off from industrial areas can be heavily contaminated and it’s important that this water be treated before being released underground as it can hamper the ecology of an area. Retention tanks provide the space to hold storm water in a safe environment where it can be subjected to any required treatment procedures and then released.
How useful are these tanks
When used properly, storm water retention tanks can prove to be very beneficial to the environment and also prevent existing structures from being overwhelmed. Not only this, a retention tank can also be used to treat storm water for E. coli and other harmful bacteria so that these are not released into the environment.