septic tanks

How does it work?

A septic tank is a system, typically installed underground, which collects sewage, allowing the waste to decompose before disposing it through the means of a soakaway. A septic tank will treat wastewater from premises which are not connected to the mains drainage system. A septic tank works like a simple sewage treatment plant, except that it is a completely passive system powered entirely by gravity.

The process begins with waste-water flowing in through one end of the tank Waste material can settle in the tank and is digested by natural bacteria which must be allowed to breed within the tank. As new water enters the tank, it displaces the water that's already there. This treated effluent drains from the tank’s outlet pipe, normally to a soakaway field drainage system.

There are three layers to the waste that is collected within the tank:

  • Top: The Scum Layer – Waste that can float will inhabit this layer.
  • Middle: The Water Layer - This water contains bacteria and chemicals like nitrogen and phosphorous that act as fertilizers, but it is largely free of solids.
  • Bottom: The Sludge Layer – Anything that is heavier than water will sink here.

To keep the septic tank running efficiently, it is recommended that the sludge built up within the septic tank must be cleared out every 12 months.

Installation & Repair

At Bates Environmental Ltd, we understand the importance of having a septic tank, and the careful consideration and planning required for the installation process. It is also vital that the customer understands the functions of a septic tank and acknowledges the steps needed to allow for installation, such as having enough space for the septic tank, being aware of local factors (i.e. water tables and soil types) for septic tank emptying and drainage.

Bates Environmental Ltd have acquired a vast amount of experience in planning, installing and repairing / maintaining septic tank systems. If you are experiencing problems with your existing installation, then contact us to enquire.

Choosing A Septic Tank

When it comes to choosing a septic tank, there are many factors that should be taken into consideration.

The main points of focus would be the size of the tank that you would need to buy, usually determined by the size of the property, and the rate at which the water flows through the soil on the property.

Bates Environmental Ltd recommend the installation of a suitable size septic tank from the Marsh Industries Green Filter range, offering the following benefits:

  • No Smell and Foul Odours in the Soil and Grass
  • Low Carbon Footprint
  • No Electricity
  • Kinder to Your Local Environment
  • No Blocked Land Drains
  • Low Ongoing Maintenance
  • A Cleaner Garden for Both Play and Relaxation

Emptying A Septic Tank

Regardless of what many believe, not all septic tanks are the same when it comes to how often they need to be emptied.

The Environment Agency recommends that septic tanks should be emptied or desludged once per year by an operator licenced for the carriage of waste by the Environment Agency.

A septic tank is considered full when 35 percent of the interior space is occupied by solid material, or sludge. The tank will always be full of water, which is what you will see if you open the tank. The solid materials gather at the bottom of the tank and settle there. Eventually, this sludge must be pumped out. If the tank is filled above 35 percent, there is a risk of solid waste entering the field lines to the drainage field or clogging of the inlet to the tank. Both situations can result in major problems and costly repairs.

Bates Environmental Ltd can offer a septic tank emptying service, as well as advice on the optimum emptying schedule for your individual septic tank.

We offer regular inspection, servicing and maintenance contracts for domestic and commercial customers. We are also able to offer an emergency call out service. Our Freephone 0800 0433711 is manned 24 hours a day all year round.