Betty Lake Water Treatment Plant Upgrade, Canada

Betty Lake Water Treatment Plant at CFB Wainwright will be upgraded with a new filtration system and an immersed membrane system, which will improve the quality of drinking water for both the military base and the adjacent Wainwright town.

The estimated investment for the new filtration system is $11.4m. The upgrade will include installation of the Zenon-GE immersed membrane system. The new 16m x 12m system will come up to the south of the existing plant on a total area of 192m².

The plant provides 82% of the treated drinking water to the town of Wainwright and the remaining 18% to the Canadian Forces Base Wainwright. The upgrade will improve the quality of drinking water for both regions.

The primary water supply for the plant is the Battle River, a major tributary of the North Saskatchewan River. The new filtration system will help treat approximately 1.4 million cubic metres of water annually.

Treatment

Water from the Battle River is pumped up to Betty Lake via a 2.2km pipeline, which carries 1.4 million cubic metres of water every year.

The multi-barrier approach used at the plant involves establishing and maintaining a series of barriers that prevent pathogens. These barriers assist in the protection of source water, treatment, distribution system integrity, monitoring water quality and adverse water quality alarms and response.

The Department of National Defence (DND) identified the need for an additional barrier to ensure safe supply of drinking water and proposed an addition to the water treatment plant for an immersed membrane system that uses ultra-filtration (UF) membranes.

By receiving this new upgrade, the plant will be able to provide an additional barrier in the water treatment process. This multi-barrier approach filters pathogens in raw water, particularly high concentrations of Giardia cysts and Cryptosporidium oocysts, ensuring the safe supply of drinking water.

The Giardia cysts and the Cryptosporidium oocysts found in the water consist of pores with a size of 1-7 microns. The ultra-filtration membrane system typically has a pore size of 0.01 microns. This prevents the passage of pathogens.

The immersed membranes will serve as a polishing step in the water treatment process after the existing dual-media filters. Since the UF membrane system cannot eliminate all viruses alone, chlorination will still be used in the treatment process. After the project completion, the operation of the plant starts with pumping the raw water from the Battle River to the Betty Lake through the constructed membranes into the centre of the straw and then that will be sent to the tank and chlorinated. The finished product will be 99.999% free of cysts and oocysts.

Waste treatment

The immersed membrane upgrade results in additional process waste, released into the south lagoons. Process waste evolves from the immersed membranes following three operations – back pulsing, maintenance cleans and recovery cleans. Waste generated from these three processes collectively mixes with the waste from the existing water treatment plant.

These waste streams reach the Betty Lake through the south lagoon.

The entire wastage is either channelled to north slough or back to Betty Lake depending on the nature of the filtration process.

Engineered lagoons

In order to comply with an alternative method to manage the current and future waste streams, the DND will phase the plant upgrade to include improvement and construction of well-designed and engineered lagoons. The best method to handle, treat and dispose of the process waste will be reviewed based on the technical, environmental, operational, construction and financial requirements.

Immersed membranes and process waste management systems may not be carried out simultaneously due to budgetary constraints and project timelines.

The engineered lagoons for the effluent management will be built within a year of the completion of the immersed membrane system.