One problem we will be looking for is referred to as a “low area” in a pipe. You might also hear this referred to as a “sag” or a “belly”. Basically, if there’s a low area in one of your pipes, it means that the pipe has somehow lost the gradual slope which should keep contents running smoothly. Instead, there is a dip or sag in the pipe which causes contents to get stuck in the bent or sagging part. If a pipe is well-installed, it will have a “positive slope,” or a continuously down-hill slope, for the whole distance of the pipe. When we do your sewer inspection, we’ll be looking to make sure that all of your pipes have this positive slope so that you can avoid backups and blockages.
Generally, sewers are designed to have about a ¼” fall per every foot of distance so that a gradual, easy slope is created. This can be reduced to 1/8” per foot, but only under special circumstances when a steeper slope can’t be accommodated. Of course, the steeper slope is preferred as it will keep the contents of the pipe moving more smoothly.
We identify low areas when we observe that the sewer is still holding water, even after the flow of contents has ceased. The standing water in the low area will disrupt the incoming contents when water is flushed down the pipe and if there are several low areas, the flushed water will significantly lose speed as it goes through. Without this speed, it becomes harder and harder to clear the pipe of all water, debris and waste and eventually the pipes can become seriously clogged.
There are many causes of low areas and it’s hard to tell where or when they might occur. Loose or shifting soil can cause the pipes to settle incorrectly, a broken pipe can easily create a low area, and general poor installation can lead to an increased possibility of low areas. No matter what the cause might be, once we identify a low area, there’s only one way to fix it. The only solution is to excavate the soil from around the pipe and replace the affected section so that the pipe can continue at the correct slope. Due to the obvious difficulties in fixing a low area, we will only recommend that the low area be corrected if it is causing a real problem for you. If we identify a low area in the course of the sewer inspection that isn’t actually causing an issue, we will not recommend that you spend the money to get it fixed at that time.
Now, you might wonder if you should get a pipe fixed, even if it isn’t causing an immediate issue, so that you can prevent a future problem. Shouldn’t you get all low areas fixed?
No, not necessarily. Luckily, we have a thorough understanding of how these issues are created and which areas are more likely really turn into real problems for you later on. We’ll ask you several questions to get the “medical history” of your pipes and sewer system. Prior to a sewer inspection, it wouldn’t hurt to think about whether you’ve had problems with the system in the past. If you have any service records available, those will be helpful to us as well. We can take this information and combine it with our camera inspection to help us determine the best course of action for you and your home.
We’ll also look at several other areas to determine if your low-area pipe needs repair. We’ll take into the account what kind of pipe it is, how much water volume it needs to handle, if there’s been a change in the low area, to what extent the roots are interfering with the pipe as well as what kind of build-up might already be occurring the pipe before we give you our recommendation. Remember, we aim to be your trusted source for sewer inspections anywhere in the Denver area. It’s in our best interest as well as yours to give you a real, honest recommendation about what to do with your low-area pipes.