Editorial - Sewage Treatment Wasted - the Victoria (BC, Canada) example.
A previous Editorial (Chapman, 2006) provided the background
for issues regarding sewage discharged by the City of Victoria (British
Columbia, Canada) and environs (the Capital Regional District,
CRD). In brief, the sewage receives preliminary screening to remove
solids larger than 6 mm prior to discharge more than 1 km
offshore in roughly 60 m deep, well-mixed marine waters with
strong tidal currents. Despite scientific evidence that there are no
major environmental or human health impacts, this discharge of
‘untreated’ sewage has been a constant irritation to the city’s US
neighbours and to environmental groups, has resulted in a large
number of lay opinions in the popular media (radio, television,
newspapers, magazines), and finally resulted (July 2006) in the
British Columbia Minister of the Environment directing the CRD
to move to secondary sewage treatment.
Prior to this direction, an independent expert scientific review
had been completed under the auspices of the Society of Environmental
Toxicology and Chemistry (SETAC; Stubblefield et al.,
2006). This independent review made an important point that appears
to have been overlooked by the Minister and others in favour
of secondary treatment. Specifically, stormwater, sanitary and combined
overflows, and other discharges, particularly into the surface
waters in Victoria’s harbours, present more pressing environmental
issues than the current offshore submarine sewage discharges. But
there was no opportunity to properly discuss and evaluate the SETAC
review; the CRD’s plan to review the SETAC report over a 5-
month period, with public input, prior to deciding how to proceed
was obviated by the Minister’s direction, which was handed down
just two days after the release of the SETAC report.
The SETAC review, previous assessments, and subsequent expert
opinion by local medical health officers have all confirmed
that there are no major human health concerns associated with
the sewage discharge. Granted, gastrointestinal illness and/or ear
infections could conceivably occur if individuals were in offshore
waters when, during certain periods in the fall and winter, excessive
rainfall entering the drainage system can cause the sewage
plume to surface. But this would not be a common occurrence to
say the least, and the risks would be far smaller than those posed
by the combined-overflows problem specified above.
The SETAC review also confirmed that the outfalls were not
causing major adverse environmental effects. The review specifically
stated ‘‘There is no reason to believe that serious human
health effects or severe ecological consequences not yet in
evidence will arise in future” but, not unreasonably, the reviewers
admitted that they could not predict future risks due to emerging
contaminants of concern (‘‘the larger problem is with estimating
the likelihood of events that have not yet, and might never, occur”).
The Minister’s direction to proceed to sewage treatment was
neither based on the evidence of present environmental or human
health impacts, nor on the evidence for future environmental or
human health impacts. Moreover, it was not based on any recommendation
from the SETAC review. Rather, it was based on the possibility
of future risks (on hazard, not actual risk); undue reliance
was placed on a report that only assessed total concentrations of
chemicals in the environment, not their bioavailability or their
environmental effects (MacDonald and Smorong, 2006). The Minister’s
direction was also, presumably, based on ‘doing the right
thing’.
The Victoria sewage situation is not unique. For instance, over a
decade ago, the City of San Diego was similarly ordered (by the
USEPA) to upgrade from primary to secondary treatment. Again
the scientific evidence did not support the need for this higher level
of treatment at that location. But environmental groups and
numerous individuals and politicians agreed it was the appropriate
thing to do.
Then a group of marine scientists, mostly from the
Scripps Institute of Oceanography, began to take an active public
role and ‘‘the public gradually learned that they were going to be
spending billions for little or no benefit, to comply with a federal
mandate that was imposed with no consideration for local conditions”
(Loehr and Brooks, 1995). Further, secondary treatment entails
environmental negatives including substantial additional
energy requirements and CO2 emissions, sludge production, and
land use associated with treatment plants. San Diego’s sewage
treatment upgrade would also have resulted in a loss of reclaimed
water. After duly considering all of the evidence, a federal judge
eventually struck down the USEPA order.
The parallels between San Diego and Victoria in terms of political
rather than science-based requirements are obvious. Costs for
secondary treatment for Victoria are predicted to be less than for
San Diego but could still well be in the billion-dollar range. There
will be minimal, if any, marine environmental benefits, and those
benefits have yet to be specifically identified. Environmental negatives
will include increased energy usage and the need for sludge
disposal, and almost certainly a subsequent deficit in both money
and political will to address the more pressing environmental issues
identified by the SETAC review and by others.
The scientific evidence of lack of harm is clear, as is the evidence
that secondary sewage treatment will not remove all
uncertainties related to emerging contaminants. Some contaminants
will not be removed from the effluent, while others will
be removed to and concentrated in the sludge that will then require
safe disposal. A focused, objective evaluation of different
sewage effluent components (e.g., nutrients, metals, emerging contaminants, etc.) is needed that will address questions such as:
(1) Is the component producing, or likely to produce, anything
more than minor local effects?; (2) If so, does it come mainly
from the effluent, or from more widely-distributed sources?; (3)
If from the effluent, what kind of treatment would take care of
it (e.g., source control, primary treatment, secondary, more advanced,
other types, etcetera) and what would be the monetary
and other environmental costs?; (4) If the problem is serious
and comes from wider sources, what can be done about it? The
value of such an evaluation to stake-holders and decision-makers,
particularly if it were conducted as a part of the CRD’s originally
planned public review of the SETAC report, is obvious. An urgent
parallel requirement for this evaluation is news media reporting
that correctly weighs the scientific evidence for both sides – benefits
versus costs – such that ‘the right thing to do’ truly does
emerge from this process (e.g., see Boykoff, 2008) rather than
from Ministerial direction, based on public opinion, that overrides
any useful evaluation.
The concept of natural sewage treatment has been criticized in
the media, but in fact waste treatment is well recognized as a useful
ecosystem service contributing to human well-being (Costanza
et al., 1997; Boyd and Banzhaf, 2007). The focus of environmental
protection is changing to preserving such ecosystem services to the
benefit of both human beings and the natural environment (e.g.,
USEPA, 2008). It makes no sense to replace a natural ecosystem
service with a human creation that is energy inefficient and has
other harmful environmental consequences.
As noted above, recommendations to examine environmental
priorities holistically before taking action have been ignored. A
great deal of money has now been committed to resolving an arguably
relatively minor environmental issue. Will monies also be
available for dealing with more pressing issues including those
identified by the SETAC review? Will the CRD’s new directed focus
on relatively expensive sewage treatment reduce or even eliminate
their present, very useful programs to address stormwater and
other overflows, watersheds and landfills? Unfortunately, we all
know the likely answer to these questions. As the cartoon character
Pogo said so long ago in a sentence that applies too well to the
Victoria sewage issue and to other environmental issues, ‘‘We have
met the enemy, and they is us”.
References
Boyd, J., Banzhaf, S., 2007. What are ecosystem services? The need for standardized
environmental accounting units. Ecological Economics 63, 616–626.
Boykoff, M.T., 2008. Lost in translation? United States television news coverage of
anthropogenic climate change, 1995–2004. Climatic Change 86, 1–11.
Chapman, P.M., 2006. Science, politics and ideology – the Victoria (BC, Canada)
sewage issue. Marine Pollution Bulletin 52, 719–721.
Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Naeem, S.,
Limburg, K., Paruelo, J., O’Neill, R.V., Raskin, R., Sutton, P., van den Belt, M., 1997.
The value of the world’s ecosystem services and natural capital. Nature 387,
253–260.
Loehr, L.C., Brooks, E.R., 1995. Judge scraps EPA-ordered sewage requirements for
San Diego. Marine Pollution Bulletin 30, 354–355.
MacDonald, D.D., Smorong, D.E., 2006. An evaluation of sediment quality conditions
in the vicinity of the Macaulay Point and Clover Point outfalls. Report prepared
for the BC Ministry of Environment, Victoria, BC, Canada.
Stubblefield, W.A., Servos, M., Gersberg, R.M., Riley, C., Simpson, D., Smith, D., Wells,
P., 2006. Scientific and Technical Review. Capital Regional Core Area Liquid
Waste Management Plan. Available at <www.crd.bc.ca>.
USEPA (United States Environmental Protection Agency). 2008. Ecological Research
Program Multi-Year Plan FY 2008–2014. February 2008 Review Draft. Office of
Research and Development, Washington, DC, USA.
Peter M. Chapman
Golder Associates Ltd.,
North Vancouver, BC, Canada,
Tel.: +1 604 904 4005
E-mail address: pmchapman@golder.com
Jay Cullen
Chris Garrett
Jack Littlepage
Tom Pedersen
Diana Varela
University of Victoria,
Victoria, BC, Canada
Rob W. Macdonald
Richard Thomson
Institute of Ocean Sciences,
Sidney, BC, Canada
Tim Parsons
University of British Columbia,
Vancouver, BC, Canada