Land-based plant would be ineffective. Chemicals are being discharged, but that doesn't mean harm is being done.
Peter M. Chapman, Jay Cullen, John Dower, Chris Garrett, Jack Littlepage, Rob Macdonald, Tim Parsons, Tom Pedersen, Rick Thomson, Diana Varela, Special to Times Colonist
Published: Times Colonist - Wednesday, April 23, 2008
SEWAGE TREATMENT: NO
We are a group of local marine scientists committed to the study, wise use and protection of the ocean. Our goal is to clarify some of the scientific issues associated with Victoria's sewage treatment, that still seem misunderstood. More information can be found at www.rstv.ca.
The Capital Regional District employs preliminary sewage treatment in which effluent is discharged through six-millimetre screens, eliminating larger objects from the effluent.
The strong, churning currents in Juan de Fuca Strait then act as an efficient natural treatment plant, using tidal energy to process the effluent and avoiding the waste of large amounts of energy in a land-based plant.
In this respect, Victoria's location is unusual and fortunate. Land-based treatment would certainly be required were the outfalls in Saanich Inlet, the Inner Harbour or on a lake or river.
Discharges through the Clover Point and Macaulay Point outfalls have caused little or no harm to the marine environment. Chemicals associated with the effluent are certainly detectable, but this does not mean that harm is being done. Biological communities around the outfalls are thriving.
Moreover, the CRD's increasingly rigid source control programs have recently led to measurable decreases in chemical concentrations.
Some of the chemicals detected in the discharge, albeit at very low concentrations, are potentially toxic and persistent.
These chemicals warrant further discussion. With land-based treatment some would end up in the sludge, presenting problems elsewhere, while others would still remain in the liquid effluent discharged from a land-based plant.
Many of the chemicals of concern enter the ocean mainly from sources other than wastewater discharge, so that land-based treatment of Victoria's wastewater would lead to a minor, even negligible, improvement. The only solution for these chemicals might be even more stringent source control or the elimination of their use altogether.
In justifying the decision to require the CRD to move to land-based treatment, the B.C. government cited the 2006 SETAC report. This report did not actually call for land-based treatment.
Although the report stated that the present system "is not a long-term answer to wastewater disposal," it did not specify exactly why, or how long the "long-term" is. Unfortunately, the CRD cancelled plans for public review and discussion of the SETAC report.
Similarly, the MacDonald Report, commissioned by the province and cited as a further reason for land-based treatment, has not received an independent review.
That report concluded that substances found near the outfalls warranted their "preliminary designation as contaminated sites." However, in the words of the SETAC report, "Note that contamination does not imply effects, but merely that concentrations are above background levels."
The SETAC report also supports our main point: Land-based sewage treatment in Victoria is a low priority for protecting the marine environment. The SETAC panel noted that "if citizens' concern is with contaminants with distant effects, and especially with their impacts on endangered species and ecosystems, it can be argued that other policies would provide a greater return per dollar."
At the local level, the nearshore marine environment would benefit from fixing of the cross-connections between the sanitary sewer and storm-water runoff systems in the CRD, as these do occasionally lead to fouling of our shores with raw sewage.
We are concerned that land-based secondary sewage treatment in Victoria would be largely ineffective with respect to major regional environmental issues and would divert public funds away from positive actions that really could provide significant marine environmental protection.
The undersigned have served voluntarily on municipal, provincial and international committees dealing with issues related to waste management and marine environmental health and would be happy to do so again.
Peter M. Chapman Golder Associates Ltd., aquatic ecologist, ecotoxicologist and environmental risk assessor
Jay Cullen, UVic chemical oceanographer
John Dower, Uvic biological oceanographer
Chris Garrett, Lansdowne professor of Ocean Physics, UVic, physical oceanographer
Jack Littlepage, UVic marine biologist
Rob Macdonald, Institute of Ocean Sciences, chemical oceanographer
Tim Parsons, UBC biological oceanographer
Tom Pedersen, dean of science, UVic, marine geochemist.
Rick Thomson, IOS, physical oceanographer.
Diana Varela, UVic biological oceanographer