Scientists on sewage treatment

By 10 local marine scientists, December 2013

Scientists on sewage treatment

We are pleased to see continuing discussion in Focus of the local sewage treatment issue. The overriding impression we have of the CRD’s continuing plans for land-based secondary treatment, or suggestions by others for tertiary treatment, is that the allegedly scientific arguments put forward in support are very superficial. Protection of the marine environment is supposedly a primary goal, but nowhere can one find a detailed, quantitative, rational analysis of what the problems are with the present system and how the proposed schemes will fix them. The BC government’s order to the CRD in 2007 was largely based on the qualitative and inconclusive SETAC report. Similarly, the federal government’s “one size fits all” regulations are clearly inappropriate in failing to take account of differences in receiving environments and hence different impacts and risks. The CRD’s willing compliance is disappointing.

Before spending a billion dollars, it would seem sensible to answer questions such as 1) What are the present or potential problems with wastewater and other discharges into the local marine environment? 2) How serious are these problems? 3) What are the major sources of the problems? 4) Will a proposed remedy eliminate or even reduce the problems without creating bigger impacts? 5) Are there better solutions than the ones proposed? 6) Is addressing the problems a high priority for marine environmental protection?

Materials of concern such as heavy metals and pharmaceutical compounds are certainly present in the screened wastewater. However, rather than declaring them to be toxic or harmless, we really need a quantitative analysis of their concentrations and effects. Such an analysis has not been officially conducted. 

Many of us in the marine science community who have examined the issues, based on the excellent monitoring work of the CRD’s scientists together with consideration of local oceanographic conditions, have concluded that 1) in spite of some uncertainties, the impact of the present system is small, and 2) land-based secondary treatment in the Juan de Fuca Strait region is a low priority for marine environmental protection. 

Much greater benefits for the marine environment could be achieved for a fraction of the cost of the proposed scheme by focusing on more serious issues such as habitat loss, harmful invasive species, and making our local ecosystem more resilient to climate change and ocean acidification.

Jay Cullen, Chris Garrett,

Jack Littlepage, Rob Macdonald,

Tim Parsons, Tom Pedersen,

Vera Pospelova, Rick Thomson,

Diana Varela, Michael Whiticar

(The above are all current, former, or adjunct professors of marine science, Tim Parsons at UBC and the rest at UVic.)