WC138 SeptOct 2024 - Flipbook - Page 14
WASTEWATER
supports genomics research and the development of innovative
solutions for a broad range of human health, environmental and
natural resource problems in B.C. and beyond.
Before we delve into the genomics of activated sludge, so to
speak, we need a look at the issue of wastewater effluent, now the
largest source of pollution to surface waters in Canada. “A high
volume of untreated wastewater is regularly being discharged into
the environment across the country,” notes Dr. Steve Hallam,
who co-leads the study, and is a professor in UBC’s Department
of Microbiology and Immunology. He is also the founding
director of the ECOSCOPE Innovation Ecosystem and former
Canada Research Chair in Environmental Genomics.
To address this, the federal Wastewater Systems Effluent
Regulations call for upgrades to secondary treatment in about
25 per cent of Canada’s wastewater treatment plants over the
coming 30 years, including those in the Vancouver area. “These
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upgrades will likely be heavily focused on the installation
of activated sludge processes, among the most widely used
treatments available today,” said study co-lead Dr. Ryan Ziels,
an associate professor in Civil Engineering and Environmental
Engineering at UBC. “But as plant managers know, activated
sludge processes have a serious weakness in that the bulking
and foaming bacteria (BFB) they contain can cause complete
loss of process control and significantly reduce pollution
removal efficacy.”
Of course, bulking can be controlled with adding chlorine
compounds to activated sludge bioreactors, but this strategy is
costly in both initial treatment and the need to quench chemicals prior to effluent discharge. More chemicals are typically
added than are needed due to the difficulty in measuring the
amount of BFB, and as Drs. Hallam and Ziels have discovered,
what species are present also matters.
WAT E R C A N A D A . N E T
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“Bulking can be controlled with adding chlorine compounds to activated
sludge bioreactors, but this strategy is costly in both initial treatment and
the need to quench chemicals prior to effluent discharge.”
