A septic tank shouldn't smell if it was properly installed and has been well maintained since. Therefore, if your tank has smelled since it was installed, then the installer probably didn't do a good work. However, if the smell only started some time after installation, then poor maintenance is probably the problem. There is no alternative to proper installation and maintenance, but the following methods should help you keep the odor in check:
Using a Charcoal Filter
All septic tanks emit odors whether they are properly or improperly installed and maintained; it is just that those that are properly installed and maintained manage to trap or filter out the odors. One way of doing this is to use a charcoal filter system that absorbs the smelly gases before they can escape into the atmosphere. The filter system is installed over the vents so that it filters the foul air emanating from the vents.
Charcoal is a good filtration material because its particles contain millions of tiny pores. It is these pores that trap the smelly gases so that they don't fill up your home. Note that the filters eventually stop working when the pores fill up with the gases, and the filters have to be replaced.
Maintaining the Integrity of the Tank
A leakage in your septic tank may also result in smelly odors when it leaks untreated effluent, and with it, foul smells. This is likely to be the case with aging tanks that have rusted and cracked or developed holes. Such damage may also happen due to accidents, for example, when you operate heavy machinery near the septic tanks and it damages the pipes or the tank itself. Tanks that are falling apart due to old age should be replaced, but accidental damages to the pipes may be dealt with via repair.
Ensuring Efficient Treatment
One reason a properly functioning septic tank shouldn't emit odors to the atmosphere because it produces limited foul gases, to begin with. This is the case because each septic system should have a treatment system that breaks down the effluent into fairly innocuous gases. The few smelly gases that are produced are trapped by the filtration system and covers. This means if the treatment system fails, for example, if the treatment chemicals are misapplied, the tank will produce an abundance of foul gases, and some of them will definitely reach you. Therefore, ensuring that the treatment system is efficient is another way of preventing foul odor.
Consult a plumber if your drains still smell despite your best efforts. It might be that there is a leak or another problem you aren't aware of; the plumber will diagnose and fix it. For more information, contact companies like Linn Septic Service.