The scope of work for this project included the structural rehabilitation of the water mains and the trenchless replacement of lead services, when required, from the water main to the property line.

As the seventh-largest city in North America, the City of Montreal’s Water Services Division is responsible for the production and distribution of potable water and the collection and treatment of its wastewater. It manages over 2,640 miles of water mains, of which 2,200 miles are small diameter distribution mains, which serve more than 1.6 million people, businesses and industries.

At the turn of the century, the City of Montreal conducted several studies in an attempt to help it restructure its Water Division, which at the time was decentralised between the city centre and the 19 boroughs. In 2005, this restructuring led to the founding of the present Water Services Division and the setting up of a dedicated water fund. At the same time, the city also started an asset management program, whose master plan proposed massive investments in its water and wastewater infrastructures including the rehabilitation of its water mains, for the next 20 years.

Saving with trenchless

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Every year the city spends a tremendous amount of money to repair water main breaks, in addition to the costs related to the water lost in the process. In order to reduce the number of breaks and leaks in their water system, the city started systematically rehabilitating their water mains with structural cured-in-place pipe (CIPP) liners.

In the last four years the city has rehabilitated over 150,000 ft of small diameter distribution water mains with the use of Aqua Pipe, a structural CIPP liner. From 2008–2010, the city saved over $CDN60 million ($US58.3 million) in direct costs for the structural rehabilitation of approximately 120,000 ft of water mains, compared to replacing the pipes using the open cut method.

In addition, the city also eliminated or greatly diminished many social costs associated with the open cut method. It is also interesting to note that the six filtration plants in Montreal reduced their water production by 12 per cent between 2000 and 2010 thanks to leak detection combined with the replacement and rehabilitation of its water mains.