Sewer is simply a set of pipes or drains that’s usually underground and whose primary function is to remove waste water as well as other waste materials. Generally, there are three main types of modern sewer systems and they include sanitary sewers ( also commonly referred to as foul sewers), storm sewers or surface water sewers as well as combined sewers. Now let’s take a look at each of the sewer types!
- Sanitary sewers or foul sewers. These are the sewer systems that are mainly incorporated to transport waste water and other waste matter from both homes and businesses to waste water treatment plants. Normally, they include pipes, manholes as well as pumping stations. Their function is, however, not only to carry waste water to treatment plants, but also to maintain the water quality as this is essential for public health. Here, gravity is commonly used to remove the waste water. However, in low lying areas, pumps can be incorporated especially when the waste water needs to reach an area that’s at a higher elevation
- Storm sewers or surface water sewers. The primary function of this sewer system is to carry rain water as well as melting snow ( unlike sanitary sewers that are designed to carry waste water) from the roofs and roads and then direct it straight into the streams, rivers and also other water bodies. These sewer systems can get clogged with leaves, litter and other debris which can ultimately lead to flooding.
- Combined sewer. As the name suggests, these sewers are combined. This implies that the make use of a single pipe to carry both waste water and storm runoff water to wastewater treatment plants. These aren’t very common anymore as the sewer can overflow especially when there’s a lot of rain which makes the system incapable to handling both the waste water and surface water.