What is a Septic Tank Pump?
A septic tank pump often refers to a submersible water pump that is installed either in the final chamber of a septic tank or in a separate pump sump after the septic tank. A septic tank pump is a small electrical water pump that can be submerged in wastewater. A float switch will turn the pump on and off as the chamber fills with water. A small impeller in the pump spins when the pump is on which then pushed the water up through the pipework the pump is connected to.
Why Do You Need a Septic Tank Pump
A septic tank pump is required when you need to pump the effluent from a septic tank or sewage treatment plant up to a higher level. This may be necessary when you either have a raised percolation area or soakaway. It can also be needed in a situation where the final effluent disposal location is located upslope of the septic tank outlet so effluent cannot flow there by gravity.
Installing a Septic Tank Pump in a Septic Tank
A septic tank pump can either be installed into an existing septic tank, or it can be installed in a pump station after the septic tank. If your septic tank is a single chamber septic tank then it is recommended that you do not install the pump directly in the tank. If you install a septic tank pump into a single chamber septic tank then you will pump settled solids out of the tank. These solids can then block up a soakaway or percolation area
If you have a 2 or 3 chamber septic tank then you can install a submersible septic tank pump in the final chamber of the tank. It is recommended that you install a dirty water pump that can handle small solids up to 30mm in size. Failure to do this can result in the pump clogging with small solids.
Installing a Septic Tank Pump in a Separate Pump Sump
Installing a septic tank pump in a separate chamber, or purchasing a packaged pump station is the best option for pumping septic tank effluent. A packaged pump station will generally have a pump preinstalled into a chamber with the necessary gate valves and non-return valves.
Septic Tank Filters
Septic tank filters, which are also known as bristle filters or effluent filters should be installed in front of a pump station where possible. These filters are a very simple and effective way of protecting your pump. As wastewater flows into the pump chamber, any small solids are caught and retained in the effluent filter. This filter should be installed in a 110mm/4” T piece under a manhole, so it can easily be removed and washed 1-2 times per year.
Septic Tank Pump Alarms and Controls
If you install a septic tank pump it is always a good idea to install a septic tank pump alarm. These generally consist of a float switch wired into a small alarm panel. If the pump fails then the water level rises in the pump chamber as no water is being pumped away. The rising water level activates the float switch, which in turn causes an alarm to sound and a beacon to flash. Alarms with a GSM dial-out facility are also available. A septic tank alarm gives you an advance warning of a pump failure of blockage, allowing you to take immediate action in advance if your sewers backing up and flooding.
Septic Tank Pump Costs
A standard domestic septic tank pump is not an expensive item. Typically, they cost £150/€175. If you get a professional septic tank maintenance company to fit the pump then they may charge the same amount again to fit the pump. If you have a large commercial septic system, or if you are pumping a long distance or a significant height then a larger pump may be required.