Last Word: Five Questions With: Ian Doherty, P.Eng.

How did you get involved in the trenchless industry?

 

In 1988, I was working for a plastic pipe manufacturer seeking to expand product range. Trenchless looked promising and 1988 saw me at No-Dig Washington followed in 1989 visiting SubTerra Rolldown installations in the United Kingdom. While that direction did not work out, I kept in touch with key individuals and in 1991 joined, at start-up, an installation contractor for the U-Liner HDPE fold and form liner. Unfortunately, U-Liner (when done right) could not compete with CIPP and that venture ended in late 1993. However, one could see that trenchless rehabilitation was going to be huge so I set up as an independent engineer 1994. I made my first No-Dig conference presentation in 1995, the only one on a pressure pipe rehabilitation job. Initially my projects included trenchless new construction, trenchless rehabilitation and pipe bursting. However, rehabilitation was the much bigger market then and the bulk of my trenchless knowledge was in that field. I had seen contractors mostly fail using the “basket of trenchless tools” model and around 1997 decided to specialize solely in trenchless rehabilitation. It turned out there was no shortage of opportunity in rehabilitation.

How does the infrastructure in Canada compare to the rest of North America?

Speaking now of underground pipeline infrastructure, I would say there are more similarities than differences. The same materials are used – concrete, clay, brick, iron, steel, concrete pressure pipe and plastic. On a relative basis, Canada would have more plastic pipe in the ground, especially for PVC watermains than the United States. In terms of condition, I suspect that the Canada’s underground pipeline infrastructure is in slightly better shape than in the United States, to some extent due to a number of Canadian cities being early adopters of routine annual trenchless rehabilitation programs. It is my sense that Canada is as open, if not more open, to trenchless rehabilitation than in the United States. Where this may differ is in the acceptance of methods/products where Canada has tended to be, shall we say, more cautious and ask more technical questions. It is also useful to recognize that trenchless sewer pipeline rehabilitation is more driven by structural renovation requirements and far less by infiltration control requirements. The latter drives far more rehabilitation in the United States than it does in Canada. In some areas, Canada is considerably more accepting of trenchless rehab methods, an example being watermain CIPP lining.

How has trenchless rehabilitation evolved over the time you have been involved in the industry?

One evolution has been in the reduction of products for small diameter sewer rehab. While 20 years ago there were other lining methods being both trialed and used, performance and cost has resulted in CIPP becoming the rehab method of choice. Another evolution is in larger pipe sizes meaning more big trunk sewers projects than 10-20 years ago. Sewer service lateral lining has evolved from just lining the pipe to increasingly installing one-piece CIPP solutions for both the lateral pipe and its main sewer connection. Finally, there is the evolution into watermain lining largely due to CIPP products that allow for remote reinstatement of the water services.

How has the acceptance of trenchless rehab methods changed in the last decade?

My sense is that the acceptance of trenchless rehab is outstripping the industry’s installation capacity to deliver. Perhaps the area with most increased acceptance is the consulting engineering community where the number of players seeking and taking trenchless rehab engineering work has greatly increased. Unfortunately, this has resulted in of a significant drop off in the quality of rehabilitation specifications, designs and contracts – area in which Canada had formerly generally excelled. I hope that this will be temporary.

Where do you see trenchless technology heading in the short- and long-terms in Canada?

In the short-term trenchless technology could be heading for some hiccups due to new players in the engineering community that have yet to do their homework. In the long-term that should iron out and steady growth will continue. There is the situation that the backlog of needed rehabilitation is decreasing – at least on the sewer side. The biggest growth areas are in large trunk sewer rehabilitation and watermain rehabilitation.