Plumbing follows the basic laws of nature: gravity, pressure and water seeking its own level. For the most part, you do not see it, think about it or worry about it until something goes wrong. As Murphy's Law would have it, you most likely will have a plumbing problem at some time.

There are several possibilities:

• The vent system could be obstructed
• The "P" trap may be clogged
• There could be a partial obstruction in the line between the individual fixture and the main line
• The main line could be partially obstructed

If only one fixture does not drain:

The problem lies somewhere between the fixture and the main drain.

If more than one, but not all of the fixtures, do not drain properly:

The problem lies somewhere within your home's internal plumbing system.

If no fixtures drain properly:

The problem can be either in the main line within the house or in the property's service connection that connects the home to the city sewer/septic tank.

Obstructions in the property service connection can result from:

• Everyday use
• Grease build-up
• A solid object flushed into the drain line
• A caved-in line
• A swag (dip) in the line that allows solids to settle out and eventually obstruct the line
• Roots in the line that have entered at unsealed joints, slipped joints, or cracks in the pipe

• Never flush or dump solid objects, hair, cloth, grease or animal fats into your drain system.
• You should not plant trees over or near the property service connection.

You should contact a drain cleaning specialist to assist you in resolving the problem.