INNOVATION November-December 2012

The river itself was also daunting. The fast moving Kootenay River “is a very large river with a range of flows,” and at spring freshet the melting snow pack can send down increased water, debris and pieces of ice dams, O’Shannassy relates. The horizontal directional drilling slipped under the stand of trees, the riverbank and emerged on the river’s bottom. Several methodologies were used to prevent drilling mud from moving into the river. The pipe was floated down the river and div- ers attached it to the drill stem. “We then pulled the pipe back through the drill hole,” says O’Shannassy. It was a challenging job for divers who had to watch the current and any material being swept along in the river. Once the pipe was in place, seven diffus- ers had to be attached to the pipe outfall in the river. A Harmonious Effort Pillai said that coordination and teamwork played a strong role in getting the project done. There were more than 50 technical staff that worked on this project at various stages and every engineer- ing discipline contributed to the project during design stage. Several different trade contractors contributed their expertise to successfully complete the construction. The newly updated system has enough capacity for 25 years of city growth, reduces greenhouse gas emissions by 75% and meets or exceeds CCME (Canadian Council of Ministers of the Environment) guidelines for discharge of treated sewage to

surface water (BOD and TSS of 10 mg/L each). It provides the capability to install a small mini-hydro generator where the transfer pipeline runs downhill. The upgraded irrigation pump house and computerized control system has the ability to spray different levels of water to different soil types as needed over varying weather conditions. It limits water waste. “About 99% of the water is taken up by plants,” says Hodge. The more efficient overall system is expected to yield energy savings of 700,000 kWh. “It is a unique and incredible treatment and reuse system for Canada. It is an example to other Canadian municipalities. Effluent reuse is an asset in a changing global environment where water is becoming an increasingly scarce commodity,” notes Vargas. Hodge also sees the system as an extension of nature. Water is taken from the watershed located on one side of Mount Baker, used in city households, then collected and returned to the land or river on the other side of the mountain. But, Pillai sees another harmony that has emerged with the extensive teamwork that involved all levels of government and affected parties. “One of the satisfactions with the current project is that the negative feel- ings (between the city and the environmental regulators) have turned to positive ones and the project has won two sustainability awards—the APEGBC award and the Federation of Canadian Municipalities,” he says. “That’s pretty good, isn’t it?” v

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