Luckily, we live in modern times and indoor plumbing is standard in homes and businesses alike. You flush the toilet, wash your hands, and walk out the door–you never have to think about where any of that wastewater actually went.

And let’s be honest, you don’t really want to know, which is completely understandable. Except for the fact that sometimes learning where your grey and black water goes is actually beneficial. Although physically figuring out where this water goes might be less than appealing, the knowledge alone can help you quickly diagnose any problems.

This knowledge can also help you communicate with a plumber what’s going on, allowing him to do his job more efficiently. We’re going to take a quick look at the two most common plumbing waste systems that way you don’t have to find out the hard way!

Septic Tank Systems

A house with a septic tank is often located in rural areas that might not have a centralized sewer system. A septic system actually does involve a water-tight tank that is buried underground.

This tank holds all of the wastewater from a home, including the greywater from showers, appliances, and sinks, as well as the black water which comes from toilets. The septic tank will allow the solid waste to sink to the bottom to form sludge and the oil and grease float to the top, forming scum.

As more wastewater flows into the tank, the liquid wastewater that is caught in the middle of the sludge and scum flows out into the drain field. The drain field is made out of pipes with punctured holes, buried in trenches filled with gravel.

The liquid wastewater slowly drains into the gravel then the ground, where the dirt naturally filters it. The water that the ground filters is not toxic or dangerous to the environment, in fact, quite the opposite: it is basically fertilizer for the surrounding areas.

Homes With Sewer Systems

If you live in a more populated area, there is a greater chance that your home uses a sewer system to get rid of wastewater. When your home is on a sewer system, the wastewater flows through pipes simply by using gravity and ends up in the main sewer line that leads to the sewage treatment facility.

The treatment facility typically also uses gravity and is located in a low-lying area. Once at the facility, the wastewater may be treated in one, two, or three phases. The first phase is basically a large-scale septic tank and if it is the only phrase used, the rest of the water is chlorinated to kill the remaining bacteria. If a second phase is used, bacteria are used to remove organic materials and nutrients.

However, these bacteria may only remove up to 90% of solids. Finally, if a third phase is used in a city’s sewer system, it typically involves using chemicals to remove phosphorus and nitrogen, but may also include filter beds. Finally, the water is chlorinated and discharged.

Other Waste Disposal Techniques

Although city sewage systems and septic tanks are the most common ways to treat wastewater, they aren’t the only ways to do so.

Other types of techniques include cesspools and electrical sewage treatment plants. Cesspools are similar to septic tanks but hold all waste and are pumped monthly; electrical sewage treatment plants use electricity to remove contaminants from water.

If you’ve found this article helpful, feel free to share it–and if you need help with sewage-related problems, call Zest Plumbing & Drain!

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