Preventing septic tank contamination of your well

Cathal Walsh
Environmental Blogger
Wednesday, 1st May 2019
Share this article
Blue septic tank standing upright

It is very common for people dwelling in rural areas to use septic tanks for their sewage management system. It is also very common for people in rural areas to have a private well as their home water source.  It is often the case that people have both.

It is surprising to hear that in many cases, rural well owners drink their well water each day without knowing that the well has been contaminated by the septic tank. Discharge from a septic tank can be very dangerous as it contains faecal coliforms containing E-Coli and Cryptosporidium and other bacteria.

In 2017 the EPA in Ireland issued a statement outlining that half of all septic tanks tested by them had failed their inspections. It was also revealed by them that E-Coli were present in a third of all Irish private wells tested.  It is important to remember that just because the water comes from underground does not mean that it is pure, or even safe to drink for that matter.

The EPA recommends that if you have a private well and a septic tank in the same property that the well be at least 30 metres away from the Septic tank or treatment system including percolation area or polishing filter. This distance should be increased if your well is downslope of the septic tank.

For safety reasons also it is essential to ensure that any fuel storage tanks are at least 30 metres away from your septic tank and that any household or farm chemicals are not stored within 5 metres of your well.

The EPA now requires that all domestic waste water treatment systems (DWWTS) are registered with them and are serviced regularly.

It is also necessary that you drain your septic tank regularly to keep it in order. Your septic tank will work better if you reduce the amount of waste water and solids contained within it.

Most importantly, it is important that you keep a constant watch on your septic tank. It is too often the case in Ireland that septic tanks go years without being inspected or serviced. The EPA will carry out an inspection of your tank at certain stages. Despite this it is up to the landowner to take the initiative and get the tank serviced regularly.

This is very important because as soon as any problem occurs with the tank it may contaminate the well water and jeopardise the health of all individuals in your residence. It is also true that if a problem occurs with a poorly serviced septic tank the only option is to replace it, which is very costly. Preventative maintenance is key here.

to test the safety of your well water follow the link

Share this article