Septic tanks provide what is known as primary treatment to the wastewater at properties which are not connected to the mains sewer system. Very simply primary treatment means the tank collects and treats wastewater. The way a septic tank works is it retains solids and allows them to settle so they can be partially broken down by biological action leaving only the remaining liquor to flow down the outlet drain. This liquor (normally called effluent) is then sufficiently treated to soak into the ground in an underground soak away system.
How does a septic tank work?
A typical septic tank is made up of two chambers and makes use of natural processes to treat sewage. More often than not septic tanks are installed underground using a professional installer. Wastewater enters the first chamber and separates the sewage into solids which settle at the bottom of the septic tank, oils and greases which form a layer of scum at the top, and a middle layer made up relatively clear water.
The wastewater enters the second chamber where any remaining solids are deposited and exits via an outlet pipe into a septic drain field or soakaway. The remaining scum and solids in the tank are broken down by bacteria and into sludge which should be professionally removed at regular intervals.
Septic Tank Maintenance
Septic systems require relatively little maintenance, but if you own one you need to make sure you're up to date with the current rules and must ensure that the tank operates effectively.
The sludge that remains at the bottom of the tank after the natural biological separation process has occurred, must be removed from the tank by a vacuum truck. This stops it from overflowing into the soaraway
How often it needs emptying depends on a range of factors, from the size of the tank to the amount of waste that is added to the tank, and other variables. As a rule of thumb you should empty your tank at least once per year
Septic Tank Questions
We generally deal with installations and decommissioning old tanks. By all means let us know if you have any septic tank related questions. We'll do what we can to help