From: Trenchless Technology

Written By: Tisyn Milne

While the One Call System is a good starting point to identify a utility’s location, properly exposing the infrastructure is the only sure way to know where it truly lies, and how the pipe or wire has been run. With millions of kilometers of buried utilities beneath Canada’s surface and records inaccurate or incomplete, it is surprising that there is not more property damage and personal injury occurring every time somebody puts a shovel in the ground. Even backyard landscaping can cause millions of dollars in damage when utility lines get hit, service is interrupted and expensive repairs have to be undertaken.

One can only imagine the ten-fold risk and additional expense when it comes to large scale infrastructure projects taking place across Canada. In a 2011/2012 report by Statistics Canada it was revealed that 40 percent of all damages to underground infrastructure occur due to a failure to notify, a frightening 84 percent of damages cause a service interruption, and 75 percent of all damages are due to outside force through usage of a backhoe or mechanical excavation.

In recent years, many initiatives have focused on mandating safer installation, exposure, maintenance and repair of buried utilities. While the One Call System is a good starting point to identify a utility’s location, properly exposing the infrastructure is the only sure way to know where it truly lies, and how the pipe or wire has been run. This is where hydro excavation comes in as an essential tool of visually locating utilities to mitigate the risk of striking underground infrastructure.

With current government regulation prohibiting the use of mechanical means to dig within 45 cm of buried cables or pipes, hydro excavating is an ideal method to expose underground infrastructure, drill pile holes, trench slots, install signs and poles and conduct landscaping and potholing.

A Vital Industry

What is standard practice in Canada today, began more than 50 years ago in the Alberta oil and gas fields where hydro excavation machines were used to ‘daylight’ buried gas pipes and other utility lines. Cold weather, and even permafrost, would only allow year-round excavation by using heated water, which made Hydro Excavators all the more popular.

When customers began modifying vacuum trucks and sewer cleaners for hydro excavation use in the 1970s and 1980s, and even mounted vacuum components on all-terrain vehicles to get into remote locations the demand was recognized and the manufacturing of dedicated truck-and-trailer-mounted hydro excavation units began in the 1990s due to the growing demand.

The millennium hit, and hydro excavation was already widely accepted and used by utility contractors across Canada for locating and non-destructive digging. It was around that time, that Illinois-based Vactor Mfg. introduced its first dedicated HXX Hydro Excavator as a purpose-built unit and became a leading manufacturer for this ever-growing market.

Today, hydro excavation is considered to be a best practice by municipalities, contractors and public utility organizations alike. As the HydroVac Alliance of Ontario (HVAO) together with the Ontario Regional Common Ground Alliance (ORCGA) indicate in a recent report, the size of Ontario’s hydrovac market has grown significantly since the first custom-built hydro excavators appeared. The associations estimate that there are between 450 and 500 units in operation across Ontario responsible for a total annual revenue of $180 million to $200 million.

Extremely versatile, hydro excavators can be seen virtually on every street corner where they drill holes for fence posts, poles and signs or conduct daylighting of underground gas pipes. And once you see a hydro excavator in action, you will never forget the efficiency and power this unit demonstrates while completing a job. A recent study by the City of London says it best: “…The hydrovac unit effectively replaced the hand digging requirement being completed in 1/3 of the time and with 1/2 of the crew. The cost of using a shovel and backhoe compared to a hydrocvac unit on the identical job is 4.1 times greater.”

Born To Run

As hydro excavation becomes more and more popular, the importance of zero downtime applies to most hydrovac companies to ensure they can keep up with the day-to-day demand for their services. Industry veterans such as the Toronto-based PGC Services Inc. (PGC), a member of the Powell Group of Companies, trust a full service shop of the likes of Joe Johnson Equipment for new purchases, rental units, used equipment and to regularly service and maintain their hydro excavating equipment.

Regular inspections do not only benefit operators and customers, increase safety and are better for the environment, but they also lead to higher resale and trade-in values based on the service history.

In search of a safe, cost-effective and non-disturbing option to expose underground infrastructure when performing an excavation project, the past 30 years have seen a major shift to move from backhoe digging to hydro excavating. Associations such as the Canadian Common Ground Alliance (CCGA), the Centre for Advancement of Trenchless Technologies (CATT) and the members of the HVAO have become important advocates in promoting safe digging procedures, and with the increasing use of hydro excavation, Canada leads the pack as a nation that knows how to safely deal with its underground infrastructure.