As a retired Wastewater Operations Supervisor I’ve seen and dealt with several thousands of calls relating to Sewer Back-ups and Storm events. My 30 plus years in the field have confirmed that most homeowners have no idea about the Sanitary and Storm systems and generally don’t care until it affects them directly. Once it does, they never want it to happen again. In most cases, “it” is Sewer water coming back into their home through a floor drain.

Depending on the age of your home the lateral could be Clay, No Corrode (tar and paper), PVC, Transite (asbestos Cement – generally installed on the Municipal side) or anything that the contractor had at the time that wasn’t inspected. All of these pipe materials have their own set of issues if not installed properly so installation is paramount. Potential issues:

  • Clay – generally each section is 4 feet long unless cut to fit; connected with couplings. Poor installation or outside forces like frost, thawing or tree roots will have plenty of spots to shift the pipe. 50-60 years ago the pipe would be cut using a sharp hammer with would create chips and over time weaken the pipe which could lead to longitudinal cracks and eventually a collapse.
  • No Corrode – this was popular pipe in the 40’s and 50’s made with tar and paper; some people call it “Black Pipe”. Over time with Wastewater running on the bottom of the pipe eating away it would weaken and eventually curl up and open. Once this happens the pipe loses its structural integrity and should be replaced. Rodding it out with mechanical means destroys the bottom leaving no pipe. No Corrode can also go “Egg-shaped” because it weakens over time.
  • PVC – this is newest pipe in the industry, but it also has its own set of potential issues all directly related to poor installation. PVC is installed with rubber gaskets and at times they may slip off partially leaving a section inside the pipe where debris can build up. Poor bedding can lead to “Ponding” or a dip in the pipe. This section could lead to Grease, paper and debris buildup and ultimately a blockage or back-up. If the pipe isn’t installed with a consistent slope, peaks and valleys will cause ponding, but more importantly the pipe will go “Egg-shaped” and could eventually flatten. The good news unlike Clay is that each section is 13 feet long which means fewer connections for shifting or root infiltration.
  • Transite – Besides the fact that this pipe was created with Asbestos, if installed properly it’s a very good pipe. 12 foot sections and durable it is susceptible to root infiltration and Calcite buildup.

The Sanitary system collects waste from sinks, toilets, showers, Laundry and floor drains through a series of pipes. The system is designed to flow towards the main line out on the street then eventually to the Treatment Plant. It’s a very simple system that uses gravity and Pumping Stations, but if not maintained is could affect large areas as well as individual homes. Let’s assume that the local Municipality completes all of their Preventative Maintenance programs annually, there are still multiple potential issues that could occur. In this case we’ll focus on the individual home and things to consider in advance or right after a sewer back-up (blockage). The first thing to do (right after you remove all of the items in or near the sewer water) is try to locate where the blockage is. Once a blockage occurs in the lateral; as you continue to use water in the home it will have nowhere to go so expect it to come out of the first available spot, the floor drain (Usually in the Laundry room). If water is coming out of the floor drain you know that the blockage is between there and the Main line on the street. If the water is just sitting there then the blockage could be isolated to your home and your neighbour if you’re on a Wye Connection (both homes connect to 1 pipe in the shape of a “Y” before going out to the main line. Every home should be equipped with a Cleanout (solid 4 inch lid at the front of the home, on the floor). New homes have a Storm and Sanitary Cleanout usually side-by-side you need to determine which is which. Once you open the Cleanout if it is dry (no water sitting in it and you can see the bottom), then your issue is in between the Floor Drain and the Cleanout (inside your home). If the Cleanout is full of water, the blockage is in between the main line and Cleanout (outside your home). Keep in mind that outside your home doesn’t necessarily mean on Municipal property, it still has to be beyond the property line for the Municipality to look after. Some Municipalities will rod from the Cleanout then determine where the blockage is then invoice accordingly. A good practice is to contact the Municipality and have them check their main line before you go through all the trouble of rodding. If the blockage is in the main line the Municipality is responsible for clearing it, once they do your home will drain and in most cases you can submit a claim for the damages if any.

To protect yourself from a back-up caused by a Storm event you can consider installing a Check Valve inside the home near the Cleanout or at the Floor drain. These valves will allow water to get out when the pipe is clear and close when water is coming back into the home to minimize damage. Regular maintenance should be performed to make sure they are operating as designed. You must also be aware of when the valve is closed so you aren’t using water in the home; it will not get out and could come back into the home. In the Storm event as the pipe fills it will work its way towards the next available opening (basement shower, basement toilet, basement laundry sink).

The good news is that it will be somewhat contained allowing you more time to deal with it until the event has passed.

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