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5 Reasons You Have a Smelly Drain

Smelly Drain

When you smell a nasty odor from your sink, tub, or toilet, your first thought may be that there is a problem with the sewer line. While it is true that your sewer can produce some bad odors, there may be something else down in the pipes causing a smelly drain. 

Plumbing systems are known for harboring all sorts of substances, including bacteria, germs, chemicals, and residue from different solids and liquids. Knowing what is down there causing a smelly drain is a good idea. If you can identify the source of the smell, you’ll know to contact a plumber for professional drain cleaning in Reston, Virginia

Below, we look at the five reasons you have a smelly drain. If you have any further questions, contact the Cardinal Plumbing, Heating & Air team.

1. Clogged Sewer Line

Let’s start with the most obvious reason. The sewage in your main line is not draining as it should. As the sewage backs up, it pushes the odor back through the drains and fills the house. You may also notice the same odor in your yard. If so, you may have a burst sewer pipe or a loose connection in the sewer line, and sewer water is surfacing in your yard.

A blocked sewer line is a major problem and requires the work of a plumber who can perform professional sewer line repair. An experienced plumber uses technology, such as plumbing video inspection cameras and trenchless sewer line repair, so they don’t destroy your yard while flushing out the sewage or repiping the sewer line. Once they fix the problem, the smell should go away.

2. Bacteria, Limescale, or Calcium Buildup

Food, hair, and grease can build up in your pipes. However, those items are easy to remove. With time, some of them flush through the system on their own. The toughest buildup that is difficult to remove comes from three main substances.

  1. Bacteria
  2. Limescale
  3. Calcium

Limescale is a buildup of calcium and magnesium minerals in hard water. This hard water forms when rainwater filters through rocks like chalk and limescale, picking up hard minerals along the way. Calcium deposits in pipes are common in homes with hard water or water with a high magnesium, calcium, or potassium mineral content. 

Limescale or calcium buildup smells like rotten eggs and has a metallic taste. The taste often occurs as a result of bacteria reacting with magnesium.

If you catch the buildup early on, you may be able to remove it. However, after a certain point, the buildup solidifies and can be rock-hard. In extreme cases, the buildup can damage your pipes. To prevent the buildup and remove the odor, schedule plumbing maintenance and drain cleaning at least once a year with your local plumber in Reston. Proper cleaning can prevent smelly drains in your home.

3. Unused and Dry P-Trap

The source of your smelly drain may be right around the corner – literally. Let’s explain.

Old plumbing systems used to be straightforward. The system design allows any item, water or otherwise, to drain quickly with little to no resistance. However, the straightest path down for the water was also the straightest path upward for the smell. 

A P-trap was the solution for blocking the smell and allowing it to escape somewhere else in the plumbing. The design consists of a seal with a u-shaped pipe that holds some water every time it drains down the pipe. The trap also consists of a ventilation pipe that allows the bad smell to escape the house without coming through the drains. 

The P-trap works well as long as water flows through the drain regularly. So, try running a little water if you smell a bad odor in a drain. Don’t let the drain dry out. If the odor persists, call a plumber to inspect the P-trap, ventilation pipe, and the rest of your plumbing system.

4. Poor Ventilation

If you look at your roof, you’ll notice a metal pipe protruding vertically. It is called a vent pipe. The pipe has two main functions:

  1. Release pressure buildup in the plumbing so that the water drains properly.
  2. Release harmful gasses from multiple substances in the sewer line, so they do not come through the drain.

If you notice a smelly drain, the problem could be poor ventilation.

Most plumbing vents have a cover to prevent objects or animals from getting into the pipes. Pests like rats, squirrels, and birds can get into the pipes and build homes. However, the buildup can develop inside the pipes, causing a blockage. As a result, pressure builds inside the plumbing and has to go somewhere. As you guessed, water, sewage, and odor may come through the drains. 

Plumbing vents are incredibly difficult to repair or repipe. You will need to contact a Virginia-certified plumber with the experience and tools necessary to repair or clean the vent pipe. Do not attempt it yourself, as the job can be toxic and dangerous.

5. Dirty Garbage Disposal

Most food scraps make their way to the septic tank, where they break down and flush through the sewer line. However, some scraps or objects never make it past the garbage disposal. The main reason is that many homeowners put items in the disposal that do not belong there. 

Before you use your garbage disposal, read the user manual. It will list items you should avoid putting in the disposal, such as coffee grounds, grease, egg shells, potato peels, onion skins, pasta, bones, or cigarettes.

The disposal breaks down the food that is easy to break down when it soaks in moisture. Feeding the wrong items into the disposal can cause pasting, which leads to clogged disposal. Some items can lodge between the disposal blades. If the items remain long enough, they will begin to smell. 

Schedule Clogged Drain Cleaning in Reston, Virginia

If you have clogged drains and your water or sewage is backing up, call the professionals at Cardinal Plumbing, Heating & Air. We offer comprehensive drain cleaning services in Reston, Virginia. We can take care of all your sewer and drain cleaning issues. To schedule drain cleaning in Northern Virginia, fill out our contact form or call us.

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