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Comment: Science flushes away sewage-dilution theories

A public-administration and health economist asserts that Victoria has a state-of-the-art sewage-treatment system (“The sewage emperor still wears no clothes,” comment, May 18).

A public-administration and health economist asserts that Victoria has a state-of-the-art sewage-treatment system (“The sewage emperor still wears no clothes,” comment, May 18). The rationale for this supposed state-of-the-art system is diluting sewage in the Juan de Fuca Strait.

This is a false statement, as Victoria currently has only a rudimentary screening system in place. This would not be considered state-of-the-art, even in a developing country. The 1950s mantra of “the solution to pollution is dilution” would get you laughed out of any undergraduate civil-engineering classroom today. Today’s engineers are focused on resource recovery, zero sludge generation, cost recovery and reduced greenhouse-gas emissions.

Second, the writer states that credible marine scientists believe the existing system causes negligible harm to the marine environment. This is also a false statement, as demonstrated by recent scientific publications from Washington state revealing that salmon populations are contaminated with a host of emerging and legacy contaminants, despite basic secondary sewage treatment at all nearby communities.

Ecotoxicologists know that marine food-web biomagnification will reconcentrate legacy persistent organic pollutants such as PCBs and flame retardants to dangerous levels, thus invalidating the outdated “dilution-solution” mantra.

A detailed Metro Vancouver regional district study, conducted by leading marine scientists at the Institute of Ocean Science, found the highest concentrations of PCBs and flame retardants in the Strait of Georgia are found at the Iona Island primary wastewater treatment deep-water marine outfall.

The new reality is that a large number of emerging and persistent pollutants in our modern society end up in wastewater treatment plants. These include ibuprofen, shampoos, fragrance compounds, anticoagulants, antidepressants, various endocrine-disrupting compounds, steroids, hormones, antimicrobial agents, veterinary and human antibiotics and, most recently, micro plastics. It is no mystery why our iconic southern resident killer whales contain such a high body burden of legacy persistent organic pollutants.

Chronic and acute exposure to these pollutants places B.C.’s southern resident orcas at risk of endocrine disruption, reproductive impairment, immunotoxicity and skeletal malformations. They are listed as endangered species in both the U.S. and Canada.

At present, the risks these emerging compounds pose to human health are not completely understood; however, considerable evidence has been collected demonstrating serious environmental effects. When Stanford University professor Perry McCarty, recipient of the prestigious 2007 Stockholm Water Prize, was asked: “What are the remaining challenges within wastewater and pollution to be tackled?” he replied: “Concerns with persistent organic pollutants, both in cleaning up the legacy problems with now banned chemicals and addressing the potential risk from new ones, is of ongoing and great concern.”

Some of the legacy pollutants are being controlled though legislation (e.g., federal ban on PCBs), and some of the pharmaceutical products can be diverted through innovative source-control measures, such as prescription-drug return programs; however, many of the compounds are now ubiquitous in the environment.

The rapid emergence of these products in the marketplace, and now in wastewater effluent, has created a risk to the marine ecosystem and requires new approaches to protecting our environment through source control and innovative, cost-effective wastewater treatment.

Given that wastewater treatment plants are one of the most expensive pieces of modern municipal infrastructure, and have operational lifespans of 40 to 50 years, it is imperative Victoria’s treatment system is able, now and in the future, to remove these emerging and legacy pollutants, and address emerging trends in energy and resource recovery, greenhouse-gas reductions and environmental protection.

Third, the writer states that an independent board established to guide the wastewater-treatment system will conclude that the proposed wastewater treatment will have negligible offsetting budgetary saving, and any competent business case will fail.

This completely dismisses the opportunity for B.C.’s emerging tech sector in developing sustainable next-generation sewage treatment technologies, as evidenced by the rapid global growth of Vancouver’s Ostara Nutrient Recovery Technologies.

The Capital Regional District’s decision to move forward with tertiary wastewater treatment is in compliance with federal requirements, aligned with current and emerging regulations in the U.S. and the European Union, and is endorsed by Canada’s leading civil engineers in advanced wastewater-treatment plant design. It will provide significant environmental and economic benefits and will address an issue that has been a point of national and international contention for decades.

Wastewater is not a problem, it’s a resource, and the marine environment is not a waste dump.

Ken Ashley is director of the Rivers Institute at the British Columbia Institute of Technology.