Ken’s Guide to Home Drains and Sewer Lines

How to clear drain clogs, keeping toilets running smoothly, and avoid major drain and sewer issues in Greenville, SC

How often do you think about the system that funnels dirty water away from your home? If you’re like most people, you only think of it when something goes wrong—a clogged drain, a blocked toilet, or a major problem with your sewer line.

We’re here to answer your questions about drain and sewer line problems—to help you fix minor problems on your own, to let you know when you need to call a plumber, and to alert you to when your situation is more urgent than it seems.

Scroll down to learn more or click a button below to jump to a specific section.

Contact a professional for your drain and sewer line issues

The experienced technicians at Ken’s Plumbing are available 24/7, 7 days a week. Give us a call or use the form below to schedule service.

Dealing with an emergency and need help now? Call us at (864) 392-5470 right away!

1. Parts of a home drain and sewer system

The system that carries wastewater out of your home consists of several parts, all of which take advantage of basic physics and fluid motion rather than using up electrical energy. Here are the basic elements you should know about:

p-trap icon

Local Drains

This is often what we think of in terms of drains—the exits for water at the bottom of your tub or sink. If your home has a washing machine or dishwasher, these also contribute to the drain system. The P-trap—the bent pipe beneath each drain—keeps a small amount of water in the pipe to block out smelly fumes (which then escape through a vent system and are channeled out of your home’s roof).
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Branch Lines and Soil Stack

These pipes, often hidden behind walls, carry used greywater from various drains around the house. They are angled slightly downward and grow larger the closer they get to the main line. All drains eventually lead to the soil stack, the main drain line in your home. Toilets connect directly to this stack, hence the “soil.” This large pipe funnels everything down to the sewer line.
roof vent icon


Vents introduce air into the drainage system for two reasons: first, the air keeps things flowing smoothly. Secondly, smelly gasses are able to rise up through the vents, eventually being released through roof vents, which look like small pipe chimneys. (If you’ve ever wondered what those are for, now you know!) The vent line is the least likely part of the system to cause you any trouble, so may not have known it even existed.
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Sewer Line

This large pipe beneath your home takes greywater and solids away from your house and towards either the main city sewer line or to your septic tank, if you have one. This pipe may be constructed from PVC plastic, clay, or cast iron, depending on when your home was built. Access to the sewer line is available via the waste line cleanout, usually located near the foundation of your home. It is sealed (and you’ll want to keep it that way), but it can be opened by a professional plumber if needed.

2. Local drain problems: fixing clogs and more

Bathroom drain clogs

If the water isn’t flowing down your bathroom sink or tub drain like it’s supposed to, it’s most likely caused by a buildup of hair or soap residue.

These kinds of clogs can often be manually removed by using an auger or drain snake. If that doesn’t work, you may want to shut off the water, remove the p-trap beneath the drain in question, and clean it out manually.

Occasionally a natural cleaner can break up minor blockages. Be very cautious with heavy-duty commercial drain cleaners, since these can actually damage your pipes, leading to bigger messes down the road!

Kitchen sink clogs

A kitchen sink clog may be caused by large food items or by putting the wrong kinds of items down your sink drain (in particular, meat drippings, dairy, oil, and other fatty items).

Warm oils and fats left over from cooking can travel a long distance through your drain system pipes before solidifying, so the location of the clog may be difficult to access without help from a professional plumber.

Washing machine overflows

So here’s a piece of surprising news for most homeowners—laundry lint not only collects in your dryer, but in your washing machine drain as well.

And if you never clean it out, you may end up with a washing machine overflow on your hands, especially if you have an older home (with smaller drain pipes) but a newer washing machine (with higher water output).

If these fixes don’t work …

If you can’t get to the source of a drain clog problem with any of these methods, or if more than one drain is backing up at a time, you may have a larger issue on your hands. In many cases, you may need to get a professional plumber to come assess the situation. He or she will know where to look for problems and will have access to more advanced tools for fixing the problem and getting your drains flowing smoothly again!

3. Branch line and soil stack problems

Common toilet problems and how to fix them

Clogged toilets are no fun to deal with, to say the least. For many typical clogs, a simple rubber plunger is all you need to force solids into the larger pipes of the soil stack and free up water flow.

However, some clogs can be caused by non-organic matter—such as “flushable” sanitary products, “flushable” cat litter, toilet paper that’s too thick, or other trouble-making items. Here’s how to avoid issues and keep your toilet in great working order:

Have things gotten out of hand in a really unpleasant way? It may be time to call in a professional.

a white toilet in a cream-tiled bathroom next to a white bath tub

Ken's Blog

How to Unclog a Toilet without a Plunger

Signs of a major drain system problem

Sometimes a drain problem isn’t limited to just a local drain or toilet. If a blockage or other issue is located in one of the branch lines or in the soil stack itself, you could have a major home repair issue on the horizon. These issues can often go undetected for quite some time, getting more serious the longer that solutions are delayed.

Here are the warning signs of a deeper problem that you’ll want to get checked out as soon as possible:

  • Drains throughout the house run slowly
  • Multiple drains clog at the same time, only to seemingly clear up on their own
  • Strange gurgling sounds from toilets
  • Unexplained spikes in water bills (may be due to undetected leak)
  • A mildew smell or unexplained allergies (could be from pipe leaking water onto drywall and causing mold)
  • Water from the shower backs up into a sink drain

In most cases, these are not DIY solutions most people can handle. You’ll want to call a licensed plumber, who may use a camera or other tools to determine the source of the blockage and may be able to employ a special auger to remove clogs manually.

If the problem is more serious than just a blockage—for example, if your pipes have corroded throughout your home—you may need a larger overhaul of your home drain system. Learn more about drain line repair and replacement.

4. Sewer Line Problems

Signs of a sewer line problem in your home

Sewer lines typically run under a home and often beneath the yard. Because of their mostly inaccessible nature, issues are much harder to identify and may go on for a while before you notice a problem.

Common sewer line issues we see are corrosion or cracks in pipes (which can leak contaminated water into your lawn or basement); clogs due to fats, oils, and other drain-clogging culprits; or fine tree roots that have broken into the pipes and are now blocking the water flow.

Subtle signs of a sewer line problem include:

  • Mysterious gurgling, whistling, or banging sounds
  • The water level in your toilet varying from day to day
  • Water draining slowly from tubs or sinks though there’s no clog
  • More than one local drain clogging at the same time for no reason
  • Frequent toilet backups

Less-than-subtle signs of a sewer line issue may include:

  • Standing water in your yard or basement
  • An unexplained influx of insect or rodents
  • An extra-lush patch of grass in your yard
  • An unmistakable stench in your backyard
  • An unmistakable stench in your basement

We do not recommend that you handle sewer line problems on your own.

You’ll want to get a professional plumber who can assess and fix the problem while minimizing the risk of contamination to your home or yard. He or she may be able to use the waste line cleanout to locate and remove the source of the problem, or, in the case of corroded pipes, may need to replace entire sections of the sewer line.

Contact a professional for your drain and sewer line issues

Whether you’ve got a nasty bathtub clog, a pesky toilet that won’t stop running, or a major sewer line rupture, the experienced technicians at Ken’s Plumbing are available 24/7, 7 days a week. Give us a call at (864) 242-5511 or schedule service online now.