Lifecycle considerations
When specifying coating systems, the lifecycle cost is a major consideration. Chris Hunter, vice-president and principal for water and wastewater projects based out of the Waterloo, Ontario, office of Conestoga-Rovers & Associates (CRA), a GHD company, is regularly involved with water project assessments including the development of performance-based specifications for new and rehabilitation coating systems. He leads a team of professionals in the assessment, design, and capital planning of water storage facilities across Canada. Many of the water tank projects evaluated by CRA have required total removal of the old coating systems that have reached the end of their lifecycle.

During the past decade, Chris Hunter has worked with coating consultants and industry experts to develop several performance-based coating specifications for new and existing elevated water storage tanks. The high cost of labour and environmental controls associated with these projects has risen substantially over the years.

“As we extend the life of the coating system, the lifecycle cost comes down substantially for our clients,” said Hunter.

He offered the example of a new composite water storage tank in Queensville, Ont., where a lifecycle costing approach was used for the coating selection resulting in the application of a high-quality coating system intended to minimize the long-term maintenance cycle. This was achieved with a low-VOC fluoropolymer coating system on the tank’s exterior. With its blue cone and logos from the municipality of East Gwillimbury and York Region, the project was voted one of the Top 12 water tanks in North America for 2013 in a Tank of the Year competition sponsored by a coatings manufacturer.

Selection of the coating technology to be used is often solely based on initial capital cost. However, the industry has recently started to understand the most expensive option can be the cheapest long-term option.

Growing trends
In recent years, a growing trend toward the use of logos, graphics, and even murals on elevated water tanks has been seen by Alec Hunter, project manager with Heritage Restoration, which specializes in historical restoration and the renovation of water tanks.

“The logos are definitely getting more intricate,” Alec Hunter said. “In the past, they were mostly bold letters with the town’s name.”

The expanded use of logos and graphics has been accompanied by the growing use of fluoropolymer coating systems offering outstanding resistance to ultraviolet (UV) light degradation for unprecedented long-term gloss and colour retention.

Exterior graphics for the Chatham-Kent tank were designed by a graphic artist using a blue and green colour scheme representing the region’s fertile land and abundant waters. At a dedication ceremony to unveil the water tank’s new design, public officials applauded the renovated landmark as a source of community pride promoting Chatham-Kent as “the municipality that is truly cultivating growth, shore to shore.” The water tank was also voted a Top 12 Tank of the Year in 2014.

Typically, water tanks in Canada are white with a blue cone or solid white, according to Alec Hunter. Heritage Restoration has over-coated or recoated every style of elevated water tank, from standpipes and spheroids, to multi-legged and composite towers.