Septic Tanks
Septic Tanks are two chambers units designed to separate waste solids from waste liquids to BS6297 standards
When water is outflowed to the septic tank, the solids remain in the first chamber while the liquid passes via a 2nd chamber to an irrigation system which should be suitable sized by means of a percolation test as detailed in PPG4 and BS6297. The chambers should be periodically de-sludged
Our horizontal septic tank offers easier access for maintenance and installation is less expensive than cylindrical unit
A septic tank is a small scale sewage treatment system common in areas where no connections to main sewage pipes are available In the UK they are generally limited to rural areas
The term "septic" refers to the anaerobic bacterial environment that develops in the tank. The waste is decomposes or mineralizes before liquids being discharged
Periodic preventive maintenance is required to remove the solids which settle and gradually fill the tank, reducing its efficiency which is important to maintain the outflow. A septic tank generally consists of a tank (or sometimes more than one tank) of between 4000 - 7500 litres which is connected to an inlet wastewater pipe at one end and a septic drain field at the other. These pipe connections are generally made via a T pipe which allows liquid entry and exit without disturbing any crust on the surface. The design of the tank generally incorporates 2 chambers which are separated by means of a dividing wall which has openings located about midway between the base at the top of the tank. Standard anyway covers and lids are fitted to both chambers via a 600mm turret.
Wastewater enters the tank, allowing any solids to settle in the 1st chamber and any scum to float. The settled solids are digested anaerobically which then reduces the volume of solids. The liquid outflow passes through the opening in the dividing wall into the 2nd chamber where further settlement takes place. The settlement in the 2nd chamber results in the outflow draining in a relatively clear condition from the outlet into the drain field
Any remaining impurities percolate through the soil and eventually return to the groundwater via evaporation and uptake through the root system of plants etc assisted by any pipe work or drainage systems
Waste that is not decomposed by the anaerobic digestion must be periodically removed from a septic tank or it will overfill resulting in undecomposed wastewater discharging directly into the drainage field.
The tank has to be emptied periodically and the timescale depends on the input of solids , the volume of the tank, the amount of indigestible solids, and the ambient temperature. Ultimately the frequency varies greatly and depends on usage but periodic inspection and pumping of the septic tank is essential
Please note the following items cause potential problems with the sceptic tank.
Excessive dumping of cooking oils and grease can cause the inlet drains to block. Oils and grease are often difficult to degrade and can cause odour problems and difficulties with the periodic emptying.
Flushing non-biodegradable items such as cigarette butts and hygiene products such as sanitary towels and cotton buds will rapidly fill or clog a septic tank; these materials should not be disposed of in this way.
Certain chemicals may damage the working of a septic tank, especially pesticides, herbicides, materials with high concentrations of bleach or caustic soda or any other inorganic materials such as paints or solvents. Vehicle wash water should NOT outflow to a septic tank
Roots from trees and shrubbery growing above the tank or the drain field may clog and or
Playgrounds and storage buildings may cause damage to a tank and the drainage field. In addition, covering the drainage field with an impervious surface, such as a driveway or parking area, will seriously affect its efficiency and possibly damage the tank and absorption system.
Excessive water entering the system will overload it and could cause it to fail. Checking for plumbing leaks and practicing water conservation will help the system's operation.
Not all varieties of toilet paper were suitable for disposal in a septic tank as they did not deteriorate sufficiently