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Septic smell outside after heavy rain: Causes and treatment

Keeping your septic tank healthy is a very important step to avoid any back up and smells. Usually, when there is a septic smell outside after heavy rain, it’s an indicator that something is failing with your septic system. In many cases, the smell is caused by heavy rain.

If your septic system is emitting unpleasant odors simply because of change of weather, specifically after heavy rain, it´s time to hire trained professionals to inspect and perform maintenance on your septic tank.

A smell from your septic tank after rain usually signifies a problem, either with your septic tank or with your general house plumbing. If your plumbing system is unable to get rid of dirty water, you’ll always have a foul smell hanging around after every rain.

When it rains, the air becomes heavy and doesn’t allow for proper release of methane gases through your vent. As a result, the gases remain on the ground because of the atmospheric pressure, which results in a foul smell. This happens because the air is less dense making it difficult for gases to rise. If there’s a loose toilet gas ring in your house, then the added pressure from the rain can push these gases through into the house, resulting in a bad smell.

If you’re noticing the smell coming from inside your house, it could be due to an issue with plumbing, the seals around your plumbing could be loose or broken which allows septic gases to escape into your home.

The possible solutions might depend on the smell. If the smell is only stronger when it rains and it’s only noticeable outdoors, then you may not need to do anything as this is normal. Since the septic tank works to dispose of sewage, it’s only normal to perceive a weak smell from around the tank.

However for peace of mind, we always recommend having your septic tank professionally checked.

If the smell is inside your home then you definitely need to hire a trained professional to check your indoor plumbing. Keep in mind that if the smell prevails even when it’s not raining, it’s likely that there might be an issue with the biological function of your system.

A full septic tank isn’t something that happens very often. If you use the tank properly, it should last for about four years before needing a pump. If you have pumped your septic tank recently, the smell may be caused by the pump which will naturally fade away in time.

In conclusion, when there is a septic smell outside after heavy rain, it’s because the tank is full, a pipe is leaking or useful bacteria are dying, and in cases where the smell is mild, it’s completely normal.

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