Yes, a septic tank can get full. If this happens, you might run into issues flushing your toilets or draining your sinks. You may also notice your pipes making gurgling noises or the smell of sewage floating around your house. Other signs of a backed-up septic tank include water pooling or fresh, healthy grass growing above your drain field.

Septic tanks appear full after pumping because the liquid levels have returned to normal. If you can see the pipe, the tank is empty. However, heavy rain can cause septic tanks to fill faster than normal. You might also have leaky pipes or faucets, causing extra water to drip down the drains and into the septic tank.

A septic smell may be harmful because sewer gas is dangerous depending on the exposure amount and length of time. Sewer gas is made up of multiple gases, including hydrogen sulfide, methane, ammonia, and carbon dioxide. Some of these gases, like hydrogen sulfide and ammonia, are toxic to humans and can be fatal in high concentrations or long exposures.

There are a few signs that indicate a failing drain field. For instance, if your septic tank starts requiring more pumping than normal, your drain field might be failing. Other signs to watch for include poor drainage after rain, standing water or sewage over the septic system, a strong septic smell outside, new and healthy grass growing over the drain field, and plumbing backups in your sinks, bathtubs, or toilets.