Sewer connection renewal

Why did I experience a sewer back-up?

There are a variety of reasons why a sewer system can back up, ranging from objects being accidentally placed into the private plumbing system to complete collapse of the sewer pipe.

Often, persistent tree roots penetrate old sewer pipes while searching for nutrients and moisture during the dry summer months. The Sewers Operations Branch spends considerable time and resources clearing tree roots from sewer mains and house connections.

Why should I replace my sewer connection?

There are thousands of older homes in Vancouver, many with the original sewer pipes still in use. Much like the roof of your home, a sewer connection has a "life span". Unlike a roof, however, it is difficult to determine the condition of a buried pipe. Deteriorated sewer connection pipes are vulnerable to invasion by tree roots, and back-ups can occur.

If you have a single pipe connecting your property to the sewer main, replacing this with two pipes will enhance the environmental performance of the sewer system. The City is systematically eliminating single connections and requiring homeowners to replace them with two connections on redevelopment or significant renovation. The two-pipe or separated system allows rainwater runoff to be conveyed in one pipe and sewage to be conveyed in another. Separating the two types of waters helps keep sewage away from our streams and beaches. All buildings will be required to have a two pipe system by 2050.

How are sewer services repaired or replaced?

When sewer services fail, the conventional means of repair is to excavate the ground, find the pipe and perform the mend or renewal. Roads, sidewalks, yards, driveways, and landscaping may be disturbed when locating and repairing sewer pipes. This means of repair is referred to as "open trenching".

Sewer servicess can sometimes run directly underneath other utilities and large trees with extensive and sensitive root systems. In these situations, repairs can be difficult and expensive because they require hand digging around the utility or roots. Sewer Operations have been successfully using a trench-less form of technology referred to as "Pipe Bursting" to renew selected sewer-lines and main-lines within the City.

Pipe bursting is one trenchless method available today to replace failing sewer service lines. A launch pit is dug at one end of the failed sewer pipe, usually near the home, and an exit pit is dug at the other end, usually near the sewer-main. Constant tension is placed on the bursting tool from the exit pit by operating a hydraulic puller.

The pulling cable is fed through the old sewer connection and is attached to a steel bursting head positioned on the old pipe at the launch pit. A roll of seamless high-density polyethylene pipe is fed from the launch pit and is pulled behind the bursting tool.

As the bursting tool pushes forward, it employs the tension from the hydraulic puller and makes use of the alignment of the old sewer connection to guide the new pipe into place. The bursting component of the work takes relatively little time to complete.

Not every failed sewer connection can be pipe-burst. Primarily the old pipe must be relatively straight, free of dips and bends and blockages. Furthermore, there must be sufficient area on private property to dig a launch pit and feed the new pipe.

Pipe Relining

Pipe relining is a seamless way of repairing pipes with very little excavation involved. Damaged pipes with cracks or root infiltration can be fixed by inserting a long cloth sleeve into the existing pipe. The sleeve is treated with epoxy resins and molded to the inner wall of the host or existing pipe with compressed air. The liner cures or cooks to the wall of host pipe and after several hours, it is ready to stand alone. When everything is complete, you have a pipe within a pipe. The longevity of pipes repaired in this way are typically half of that of a replaced pipe.

How would I qualify to have my sewer service replaced?

For the City to consider sewer service replacement options, there firstly must be a documented history of sewer service blockages of which the City is fully or partially responsible for. Secondly, there needs to be an indication that a City managed sewer-line maintenance program is no longer effective or has become exhaustive.

Homeowners are expected to make the necessary repairs to remedy pipe blockage problems by improving the private portion of the connections, primarily by replacing the connection with root resistant pipe. If you have fully replaced the private portion of the sewer service and the City portion is in poor condition, then please contact a citizen service representative at 3-1-1 and we can visit the home and consider City replacement options.