New Plumbing Coupons: Click Here to View Current Discounts

All You Need to Know About a Plumbing Drainage System

Storm drain

The plumbing system in your home does two basic things: it brings water to you through faucets and other sources, and it removes water through features like sinks and drains. That second task is exceedingly important because most of the time, the water being removed contains waste such as food particles, cleaning chemicals (which, despite their function, can be harmful if ingested), and sewage. Your drain plumbing has to remove that wastewater without contaminating drinking water or leaking sewage, both of which can lead to dire health consequences and disgusting messes in the case of leaking sewage.

So, what is drainage? It’s much more than water disappearing down a drain or toilet, never to be seen again. If you simply want to define drain, that’s the fixture the water goes down, but drainage itself encompasses that and the process of moving the used water from your home to a designated safe place for it. Depending on the type of drainage system, that place could be a wastewater treatment facility, a retention pond, a septic tank, or a sewer line, just to name a handful of examples.

It’s useful to know how drainage systems work, what types there are, and what common issues you might encounter with a drainage system

How Does a Drainage System Work?

Pipes deliver clean, fresh water from their source to fixtures such as faucets and toilets. Those fixtures all have their own drain lines, which, mostly through gravity, collect the used water and waste and send it to the main drain line. The plumbing in drain lines is sloped so that the water flowing through it can reach its next or final destination easily.

In a drainage system, there’s more at work than just piping for the water, though. To help the used water flow more efficiently, vent pipes play a role. Attached to the drain lines at each fixture and protruding through the roof, vent pipes provide air pressure that helps the drains flow more smoothly. Outside, the vent pipes are capped to keep animals and unwanted moisture from getting in while allowing sufficient air flow into the system.

Drain pipes also have traps that collect dirty water and help keep sewer gasses from getting into a building. That latter function works because the traps seal the drain pipes. There are two types of traps: S-traps and P-traps. Typically, S-traps go with toilet plumbing, while P-traps are used for sinks, showers, and tubs.

What Types of Drainage Systems Are There?

There are four main categories of plumbing drainage systems. They all have their own distinct functions to perform, so while they are similar in that they provide drainage, the way they do so differs by the type of system.

Potable Water System

Potable water is water that’s safe for you to drink. In a potable water system, there are multiple pipes connected to a single system. This allows people to access safe drinking water throughout an entire house or other building. The system also includes valves throughout it that allow for the cutting off of the water supply in case of a leak, burst pipe, lack of use, or other reasons. Water meters are installed to measure the amount of water being used.

Sanitary Drainage System

Removing and transferring wastewater that can cause odors is the purview of a sanitary drainage system. A series of pipes dispose of the wastewater correctly.

While one may think primarily of water flushed down a toilet being the focus of a sanitary drainage system, these systems also handle water from doing laundry, rinsing dishes, etc. The system collects the wastewater and transfers it to a sewer system or septic tank.

Stormwater Drainage System

If you’ve ever seen holes in a sidewalk where the street and a curb meet, you’ve seen part of a stormwater drainage system. Storm drains carry excess water away from your home and channel it into larger drainage systems. This keeps water from pooling around your home, where it can harm grass, leak into a home, or damage the foundation. Unfortunately, standing water also is a perfect breeding ground for pests such as mosquitoes.

Although they aren’t considered a part of your plumbing, gutters also play a vital role in stormwater management. Make sure to clean your gutters regularly, and keep an eye out for trouble signs such as water damage inside the home, peeling paint, splits in gutters, and sagging or overflowing gutters.

Surface Drainage System

A dedicated surface draining system may not be necessary if a home is on a sloped property; if that’s the case, the main concern is where to direct runoff if there are sensitive spots you don’t want too much water coursing over.

However, on flatter properties, a surface drainage system is important to avoid the same problems mentioned above with stormwater management. In this type of system, shallow ditches run parallel to one another, acting as canals for water runoff, directing it into the main storm drain.

What Are Some Common Issues Drainage Systems Can Have?

Be aware of common issues drainage systems can have, and always be alert for signs of them so you can address the issue before it becomes a major one.

Clogged Drains

Hair and other debris can build up and clog drain pipes, causing slow draining or backups. If pouring a chemical cleaner down the drain doesn’t work, or if you’re repeatedly doing this, call our professional plumbers for drain cleaning services in Asheville.

Breaks and Leaks in Sewer Lines

Sewer water can contaminate the ground when there is a break or leak in a sewer line. This is a job for a professional plumber.

Breaks and Leaks in Septic Tanks

As in the case of this occurring with sewer lines, ground contamination is a risk, and you should call a professional plumber.

What Can You Do When Your Drainage System Has an Issue?

When there are problems with a plumbing drainage system, it’s best to rely on a trained professional plumber to diagnose the cause and fix things correctly. Four Seasons Plumbing has been a trusted provider of plumbing services in Asheville for years. We are fully certified and insured, and all of our plumbers are trained and licensed and have passed extensive background checks.

If you need plumbing maintenance, installation, or repairs – contact us for a fast, reasonable quote!

Max Rose - Owner of Four Seasons Plumbing


Max Rose

Max Rose is the owner of Four Seasons Plumbing, a plumbing company in Asheville, North Carolina.