We have been doing several sewer line replacements lately and although some times they are a lot of work. The ones we have have been installing recently have been extremely difficult for our Techs.
When we go to check on a job for a clogged drain and run our sewer machine cable through the customers main sewer line. It stops, will not go any further and pulls back mud or clay you know you will have a major problem with that drain line. At this point we must either locate the spot with our cable or the customer has the option for us to have the clogged drain line break location found by running a camera locator into the main drain lines. With the camera locator you have a camera on the end of a special fiber optics cable that hopefully you can insert it in far enough to see the problem. If you can get the camera all the way to the problem area or broken pipe then your camera has to have a sonde {which produces a signal that the sonde locator can pick up}. Your sonde locator looks something like a metal detector and will receive the signal from the sonde. This will give an accurate location on where the device is, the depth of the device and the break or collapse in the sewer line. Hopefully at this point we will be able to remove to camera locator because some times they will get caught in the line. If it gets caught you can sometimes remove it when the line is dug up. But not always and they will become damaged. It is a very expensive piece of equipment costing in the range of ten thousand dollars.
The problems lately have been in a part of town where most of the houses have basements. This makes fixing the broken sewer line much more difficult because these houses with basements have very deep main sewer lines. The older houses have floor drains in the basements and some times other plumbing like washing machines of utility sinks installed. This will make the main sewer line really deep to accommodate for the drains in the basements. The the sewer line will be stubbing out of the house at eight feet deep or deeper. Then you will have a very deep hole that you are digging. Plus the customer sometimes do not understand why their whole back yard is now a giant mountain of dirt. As if that is the biggest problem but it is not. When the sewer line comes out of the house at eight feet deep or more a bigger problem becomes evident. The city sewer main will have to be extremely deep to accommodate these houses with basements. The city sewer main can be twenty feet deep or more. This presents a Major problem. When you are digging this deep the top of the hole at the main is going to be huge because the side of the hole will have to be on a forty five degree angle. The reason being is it could collapses in on our plumbers while they are in the bottom working and it is very dangerous. The same thing with the ditch running from the house to the city main. So all in all our technicians have their work cut out for them.