The Department of Highways and Public works continues its work on the design of the wastewater treatment system for Dawson and the Yukon Environmental and Socio-economic Assessment Act application.
We have every confidence in this system and design team.
Many factors are involved in the procurement, commissioning and operation of wastewater treatment plants.
A design-build contracting approach was used to find a successful team to both design and build a wastewater treatment plant for Dawson. This type of contracting practise is becoming increasingly common in North America and is a best practise because it allows owners to look for both patented and traditional solutions from industry and seek out a broader range of solutions.
Because this contracting process is less common in North America, patented technologies such as the one selected for Dawson are less widespread in these markets.
The history of the Vertreat technology shows that plant closures are not due to the design of the system, but rather to overloading of the system, poor operation, or to reasons completely unrelated to wastewater treatment at the site.
For example, the operational issues at the Virden plant are not related to the Vertreat system, but rather to the operation of the sludge-handling system, which is completely separate. The Dairy Farmers of America closed the dairy at Golden Cheese in California because the cost of production became too expensive. The Vertreat system there is still in excellent working order and is an asset to the site if the future owner requires wastewater treatment.
The plant used at the Molson Brewery in Ontario was also decommissioned as a result of the Brewery’s closure. The wastewater system there produced high equality effluent over its 25-year lifetime.
Finally, the plant in King County, Seattle, was part of a pilot program aimed at evaluating innovative sewage digestion alternatives. The technology used in this case was Vertad, not Vertreat, a completely different system that digests sludge. The plant was used as a demonstration site for four years and was never designed or intended to operate beyond this point. The senior manager in King County declared the plant “a successful project.”
This Vertreat technology is very well suited to areas affected by high energy costs and limited space for wastewater treatment solutions such as lagoons. Dawson City faces severe space locations due to permafrost, and the state of the ground due to the town’s mining history. Because of its northern location, energy costs are also an issue, making Vertreat an ideal choice for the city’s wastewater treatment needs.
This technology is successful worldwide and specifically suited for areas where space and energy costs are limitations, making it an appropriate solution for Dawson.
Thank you for the opportunity to clarify these issues.
Catherine Harwood, P.Eng