Potential Causes for your Treatment Plant Smelling

When you have gone to the expense and trouble of installing a sewage treatment plant, whichever kind you may have opted for, it would obviously be a great cause for concern, stress and disruption should it begin to smell foul. Surely one of the main reasons for sewage treatment is to put that waste out of sight and out of mind, right? Well, unfortunately there are quite a few distinct circumstances that can mean that your previously smoothly functioning treatment plant can drop a level or two in efficiency, leading to some worrying side effects, including that nasty smell. Let’s take a closer look at some of the most likely causes of your treatment plant beginning to release an offensive odour.

Service, service, service

A regular service of between every 6 and 12 months depending on the intensity of use is absolutely vital when it comes to maintaining an efficient treatment plant. If a regular service is not carried out, the working parts and electronic components could malfunction, leading to potentially catastrophic spills, but more often simply a reduction in efficiency. In addition, the sludge build-up must be cleared regularly, or blockages can occur and efficiency drops too. All of these can lead to a smelly treatment plant. Signing up to a dedicated servicing company like MPC is the step you need to take to guaranteeing a regular service of your treatment plant and avoid easy to fix issues going under the radar and creating costly breakages and inconvenient downtime.

Vent your frustration here

Excuse the pun, but a major cause of a smelly sewage treatment plant is an inefficient (blocked) vent or in some cases the absence of a vent altogether. The vent in a treatment plant plays an integral role in allowing the gases from the sewage to escape. ‘But surely that is what causes the smell?’ You might wonder. Well, the truth is opposite, because the slow, steady constant release of gases through a functioning vent prevents the build-up of toxic (and potentially flammable) gases that will eventually seep through the drains (in the absence of a vent) and you will find that the smell will be present in bathrooms, kitchens and toilets.


There are a few ways in which a treatment plant can become contaminated, leading to foul smells. Firstly, it is possible that greywater has been allowed to enter the tank, which can affect the treatment process. In addition, you can find cases where the overuse of chemicals in toilets and even bleach can interfere with the enzymes and bacteria that contribute to the breaking down of waste in the treatment plant and contribute to a build-up of non-treated matter that will, of course, smell. It is also very important to make sure that food waste is not getting into the treatment plant as this can also create an imbalance in bacteria and impact on the creation of those vital enzymes. A sewage treatment plant is, in and of itself, a quite delicate little ecosystem that can become unbalanced with the wrong kind of interference.