*Side note: If the problem seems to be related to only one fixture like a toilet or sink, the problem is probably isolated and doesn't involve the whole plumbing system. Typically the sink trap needs to be cleaned out or a liquid drain cleaner can be poured down the drain.(Show extreme caution if using drain cleaning products as many of them contain chemicals that can burn.) Possibly, the toilet needs to be augured. (Auguring involves putting a cable through the plumbing fixture in hopes of knocking loose the blockage)
Clogged sewer lines are a common issue in older homes, especially.It is generally caused by a blockage in the sewer line. The sewer line is the pipe that runs from the house, underground to the sewer main. A blockage often occurs in these three ways. First, a build up of material could have developed over time and slowly cut off the flow of the waste water. Second, tree roots could have penetrated the pipe and grown to the point where waste cannot pass through. Finally, the line could be old and deteriorated to the point where dirt has entered into the pipe.
When the problem is simply a build up of material, a sewer clean-out machine is going to be the best solution. There are a variety of sizes of clean-out machines depending on the size of the pipe that needs to be cleaned out. Some are ambitious enough to rent or borrow a machine and do it themselves, but it is recommended that a professional plumber be hired. The second issue of tree roots can be temporarily fixed by running through the pipe with a clean-out machine, but the roots will grow back and the problem will reoccur. There are also root-killing products that can be purchased at a hardware store but once again, this is only a temporary fix. The source of the problem is that the sewer line is compromised at some point (or many points) and water is leaching out into the dirt. Roots are drawn to this moisture, so they will naturally grow towards the source of moisture which in this case is the sewer line. They will grow in size, often times cracking the pipe or causing a greater separation in the piping joints. This can lead to the eventual failure of the pipe. The best solution here is to replace the entire line or repair the section that is deteriorated. Finally, when the line has been compromised completely, the only obvious option is replacement.
Now that the problems have been expressed, how do you know for certain which is affecting the sewer line? Many plumbing companies offer a sewer-camera service by which they send a camera through your line to identify exactly where the problems are. This is helpful because it can save the homeowner money by identifying specific sections of pipe needing repair isolating the problem and lessening the overall cost. Now repair isn't always the wisest option even though it may initially seem more cost efficient. If the sewer line is old enough and deteriorated enough it may prove more fiscally responsible to go ahead and invest in an entire replacement.
