The Blueberry River First Nation is a community of about 500, located approximately 90 kilometres north of Fort St. John in northeastern British Columbia, which has struggled with its water system for a number of years.
Drinking water from the existing treatment plant, which was constructed in 1984, does not meet current Health Canada Guidelines. In addition, the community regularly faced water shortages, and had to spend significant time and money hauling in water to meet demand.
The Blueberry River First Nation retained Associated Engineering to help determine measures to increase the quality and quantity of drinking water produced by the water treatment plant until a new one could be designed and constructed. Associated Engineering’s project team worked closely with the community and Indigenous Services Canada to develop solutions, identify measures to increase treatment plant capacity, improve the quality of the treated drinking water, and help the community conserve drinking water.
To increase the capacity of the treatment plant, Associated Engineering and its wholly owned subsidiary company, ATAP Infrastructure Management, provided a short-term solution by modifying the existing treatment process to reduce the amount of treated water used for backwashing the filters. ATAP staff also provided on-site support to the community’s operator, which has helped to optimize treatment operations.
The treatment process encompasses media filtration followed by ion exchange softeners, cartridge filters, and reverse osmosis filters to remove solids and chemicals from the raw water supply. Initially, both the existing media filters and ion exchange softeners were bypassed, eliminating the need for backwashing these systems, and thus saving water.
Project manager, Freda Leong said: “Taking the media filters and softeners off-line resulted in significant fouling of the cartridge filters ahead of the reverse osmosis filters, so we retrofitted the media filters with manganese greensand filters to decrease the solids loading on the cartridge filters.”
A bypass was also installed to allow a portion of the water from the aeration tank to be blended with water from the reverse osmosis filters. A previously drilled groundwater well was completed and connected to the water system. These changes increased treatment plant output by approximately 30%.
At the same time, the team worked with the community to implement a water service and water metering program. Water engineer, Robyn Sherstobitoff, said: “It had been noted that some straps on water service connections had corroded. This issue indicated the corrosive nature of soils in the area and suggested that there could be significant leakage at water service connections.”
As part of the project, all of the water service connections in the community were replaced, and corrosion protection and water meters were added at each service connection. These will be used to monitor water usage. Water usage metrics will be utilized to help inform the community about water conservation.
The team is now working on upgrading the reverse osmosis filters, which are old and no longer adequately remove constituents such as sodium, chloride, ammonia, total dissolved solids, and hardness.
Freda explained: “Work is underway to provide water quality and control upgrades. The next step will be the design and construction of a new water treatment plant and dedicated transmission main to the reservoir.”
This article appears in ES&E Magazine’s August 2019 issue.