What is CIPP Watermain Lining?


Cured-in-Place-Pipe (CIPP) Watermain Lining is a trenchless pipe rehabilitation method which consists of the cleaning and structural rehabilitation of the existing watermain via installation of a CIPP liner. The CIPP liner is an epoxy-impregnated flexible tube which when cured forms a hard and tight fitting liner within the existing watermain (i.e. pipe within a pipe).

Watermain rehabilitation activities are mainly conducted via small access pits that are excavated at various locations (Tees, valves, hydrants, etc.) along the street. Following cleaning and CIPP liner installation, existing water service connections are reinstated from inside of the rehabilitated pipe using robotic equipment.

Installation of new fire hydrants and watermain valves, and the repair or replacement of non-operational curb stops will be completed via traditional excavation methods.


Why is the City installing CIPP Watermain Liners in this area?

The existing watermains in this area have experienced an increasingly higher rate of watermain breaks in recent years, as well as reoccurring issues with low water pressure, discoloured water, taste and odour issues. In addition, a recent 3rd party assessment of the approximately 80 year old watermains concluded that the watermains have significant structural issues and have exceeded their useful life; therefore, they are in need of replacement or rehabilitation.

The City considered both the replacement and rehabilitation options and opted to rehabilitate the existing watermains with CIPP liners. This rehabilitation method provides a cost savings over replacement, while extending the life of the existing watermain for an estimated 75 years. In addition, since CIPP liners are installed through small strategically placed access pits, it does not require complete excavation and tear-up of the street as would be required for replacement of watermains by traditional excavation methods.


How will water service be provided during construction?

During construction, your home will receive water through an above ground temporary water piping system installed along your street. A service hose attached to the temporary piping will be connected to your home via a “Y” connector at your outside tap (hose bib). This will allow you to receive water into your home and still use your garden hose. The temporary water system will be in place until the watermain lining has been complete and the rehabilitated watermain returned to service.

Is water supplied by the temporary system safe for consumption?

Yes. The temporary water system will be connected to the existing City water system; therefore, it will receive the same level of treated/chlorinated water as the existing in-ground watermains.

The City will implement a water sampling and testing program throughout the duration of the project to ensure the water is in compliance with the Canadian Drinking Water Quality Guidelines.

The temporary water system is constructed of PVC pipe certified for potable water use in accordance with the NSF International standard ANSI/NSF 61 - Drink Water System Components - Health Effects. This type of pipe is commonly used in Canada for temporary water supply systems and watermain replacement projects.

Prior to activation of the temporary water supply system, it will be disinfected/chlorinated and water samples submitted to the Public Health Laboratory for bacteriological testing, in accordance with the City Specifications and the ANSI/AWWA C651-14 Disinfecting Water Mains standards.

What if my home does not have an outside tap or the tap is not operational?

If your outside tap is not operational, it will be repaired or replaced by the contractor. If your home does not have an outside tap the contractor will install one. If installation of an outside tap is not possible, the contractor will excavate and connect the temporary water service directly to your existing service line.

Will the Contractor require access to the water plumbing system in my home?

Yes. The contractor will require access to your home to inspect the existing water service shut-off valve to ensure it is operational. Non-operational valves will be repaired or replaced by the contractor. When notified by the Contractor, the water service valve will have to be shut-off to prevent water from the temporary service connection from flowing back into the existing watermain during construction.

Will there be water service interruptions?

Occasionally, the Contractor may have to turn off the water supply to your property for a short duration.

Will residents be notified of service interruptions, plumbing inspections, etc.?

Yes. Residents will be notified 24 hours in advance of any scheduled water service interruption or request for access to complete a water service shut-off valve inspection by the Contractor. The Contractors notice of “Water Supply Interruption” or “Water Shut-off Valve Access” will be hand delivered; however, if you are not at home a notice will be left at your door.

Will there be sewer service interruptions?

No. The contractor will not be working on the sewer system; therefore, there should be no sewer service interruptions.

How will this affect traffic and residential parking?

Traffic interruptions and delays may be experienced during this project; however, kept to a minimum and two-way traffic will be maintained where possible. Every reasonable effort will be made by the Contractor to maintain driveway access to properties located within the work site; however, residents may have to park on street temporarily during lining operations, if equipment is set-up in front of their driveway. Where temporary water piping crosses driveways, appropriate ramps will be installed over the pipe (typically an asphalt ramp) to ensure driveway access is maintained.

Will residents be assessed for this Civic Improvement?

There will be no Civic Assessments charged to residents for this work since it is a rehabilitation of existing watermain infrastructure.