Toronto – Sewage treatments plants are the Top 10 Water Polluters in
Ontario, and are the largest reported releasers of mercury and lead
into the province’s lakes, streams, and rivers, according to an
analysis released yesterday by Environmental Defence. The analysis comes as
a legislative committee at Queen’s Park reviews the government’s
proposed Toxics Reduction Act, and underscores the need to include
sewage treatment plants in the Act and regulations.
“The Toxics Reduction Act will provide an important game plan to reduce
toxic pollution, but it should apply to all polluters,” said Aaron
Freeman, Policy Director for Environmental Defence. “Sewage treatment
plants are a source of toxic chemicals, and one of the best candidates
to further pollution prevention.”
The Toxics Reduction Act, a bill introduced by the Ontario government
on April 7, 2009 and based on effective strategies used in other
jurisdictions, will require industries to account for their pollution
use and emissions, as well as develop pollution prevention plans.
However, sewage treatment plants are not proposed to be included within
As a portion of total reported water emissions in Ontario, sewage
treatment plants are responsible for approximately 88% of mercury, 71%
of lead, 37% of arsenic, and nearly all chlorine releases. Data from
the PollutionWatch web site, a joint project of Environmental Defence
and the Canadian Environmental Law Association, show that Ontario
sewage treatment plants released (on-site and off-site) and
transferred: 236 kg of mercury, 14.4 tonnes of lead, 1.8 tonnes of
arsenic, and 242.5 tonnes of chlorine into air, land, and water in 2006.
The PollutionWatch web site uses data from the National Pollutant
Release Inventory (NPRI), the federal government’s national pollution
reporting program. Total releases from sewage plants may in fact be
much higher, since not all substances meet the NPRI reporting
thresholds (10,000 kg of a particular substance used in the facility).
Metals such as mercury and lead are especially concerning, given their
effects on reproduction and development. Mercury contamination is also
a leading cause of fish advisories in the Great Lakes.
Environmental Defence recommends the Toxics Reduction Act and
regulations apply to sewage treatment plants. This would encourage
municipalities and other owners and operators to set stricter pollution
limits for industries and others discharging toxics into sewers leading
to the sewage treatment plant.
Environmental Defence also recommends that reporting thresholds for all
industrial facilities be included in the proposed Toxics Reduction Act
be lowered significantly. Toronto, for example, recently passed a bylaw
to stimulate pollution prevention planning and reduce toxics discharges
from small- and medium-sized businesses. Such businesses account for
the majority of toxic substance releases in urban areas. In contrast to
the reporting thresholds in the proposed Act (10,000 kg and 10 or more
employees), this Toronto bylaw has no employee threshold and facilities
must report if they emit 100 kg of given toxics.
“Applying the Act to sewage treatment plants would reduce releases of
the many toxic chemicals these plants spew into our waterways,” said