THE EVOLUTION OF FLOOD CONTROL
The devastating impact of Hurricane Hazel in 1954
was a mobilizing force in bringing a regional
approach to flood control and water management in
Ontario.
A more coordinated approach between conservation
authorities, local municipalities and the province took
form after Hazel, and today these organizations play
a significant role in the protection of life and property
from natural hazards, such as flooding.
After Hazel, the provincial government amended the
Conservation Authorities Act to enable an authority
to acquire lands for recreation and conservation
purposes and to regulate that land for the safety of
the community.
Forests and wetlands are protected and more trees are
planted. They help to store runoff to reduce flooding.
In 1959, a comprehensive Plan for Flood Control and
Water Conservation was finalized by the
Metropolitan Toronto and Region Conservation
Authority ( MTRCA ). It included the proposed
development of large dams and major flood control
channels, and the initiation of an erosion control
program. In addition, 7,200 acres of land were
identified for acquisition.
In 1960, the Lands Acquisition Program was
implemented as the initial stage in the MTRCA
flood control plan. The intent of this program was to
transfer the liability of floodplain land from private
hands to the authority and to acquire lands
necessary for the construction of flood protection
works.
The second stage of the MTRCA flood control plan,
Conservation Authorities Act
The Conservation Authorities Act was
legislated by the provincial government
in 1946 in response to the concern by
agricultural, naturalist and sportsmen's
groups, that the renewable natural
resources of the province were in an
unhealthy state. Although the
responsibility for managing natural
resources lay with the province, the
scale of erosion and water problems
was such that it required a new
approach, and when a number of
municipal councils agreed to become
involved, this spirit of cooperation led to
the passage of the Conservation
Authorities Act in 1946. Three
fundamental concepts of this new
approach were embodied in the Act:
local initiative, cost sharing and
watershed jurisdiction. The
Conservation Authorities Act provided
the means by which the province and
the municipalities of Ontario could join
together to form a conservation
authority within a specified area—the
watershed—to undertake programs for
natural resource management. Today
there are 36 conservation authorities in
Ontario.
It is only possible to achieve the many
goals in managing Ontario's watershed
resources, with the help and
cooperation of conservation authorites'
many partners and stakeholders;
foresters, engineers, ecologists,
geologists, economists, municipal
members, volunteers, farmers,
developers, educators and citizens just
to name a few.
Over time, conservation authorities
have become involved in a wide range
of activities and responsibilities,
depending on the environmental
concerns of local residents, member
was the Flood Control Works Program. The intent of
this program was to construct as many structures
that were necessary to control flooding. The works
consisted of dams, reservoirs, channel
improvements and other infrastructure.
municipalities and the province. Each
conservation authority's watershed
management program is geared to its
local needs and, therefore, the
authority may or may not implement all
programs.
Conservation Authorities' Range of
Program Development
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Flood control dams store water during a flood, and release it
more gradually after the flood has passed.
While some of the initial flood protection planning
and implementation began within the MTRCA, as
one of the most directly affected conservation
authority’s by Hurricane Hazel, similar flood
protection activities also began soon afterward within
other conservation authorities throughout the
province.
The development and implementation of new
provincial flood plain regulations acted as a
complementary third stage in obtaining the goals of
the flood control plan. These regulations allowed for
the control of future development and inappropriate
land use activities in flood-hazard areas. As well, a
Flood Forecasting and Warning Program was
designed to monitor watershed conditions including
snow, precipitation and flows, as well as to issue
flood alerts to municipalities when conditions
warranted.
Regulations restrict new development in floodplains, allowing
rivers to flow naturally and reducing the risk to people and
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Flood Control
Erosion Control
Watershed Strategies
Floodplain Management
Flood Warning
Great Lakes Shoreline
Management
Provincial Water Quality
Monitoring
Ground Water Monitoring
Streamflow Monitoring
Urban Stormwater
Management
Waterfront Development Flow
Wetlands
Water Supply/Low Flow
Augmentation
Community Relations
Niagara Escarpment
Outdoor Recreation
Fish and Wildlife Management
Private Land Extension
-reforestation
-soil erosion/sedimentation
Windbreaks and Shelterbelts
Forest Management
Fish and Wildlife Habitat
Rural Drainage
Heritage Conservation
Network Hydro Generation
Tourism
Municipal Plan Review
Natural Area Preservation
Environmentally Sensitive
Areas
Ontario's conservation authorities have
achieved an enviable record in wetland
protection and management,
conservation education, provision of
local and regional recreational
their property during flooding.
opportunities, forest management and
heritage conservation.
Several flood control facilities were significantly upgraded or built following Hurricane Hazel.
Gauging stations became operational and a rainfall observer network was organized, providing
the ability to forecast and warn against potential flooding in the area. Operational practices were
also designed to respond immediately to changing conditions.
There are three important components to flood management and forecasting in which the
conservation authorities are responsible:
Prevention. Informing planners and the general public about the risks of flooding to promote
proper land use planning, preventing people from living and/or working in flood-prone areas.
Conservation authorities are responsible for predicting flows and water levels within their
watersheds, operating flood control structures, such as dams and disseminating flood warnings to
local municipalities and agencies.
Protection. In order to protect against flooding, conservation authorities have constructed and
maintain protective infrastructure, such as dams and dykes, or purchase lands located in
hazardous areas. Stream gauges, weather stations, surveys of snow conditions, meteorological
forecasts and computer models are used to forecast potential floods.
Emergency Preparedness and Response. Conservation authorities work with the Ministry of
Natural Resources (MNR) to provide advice to municipalities for the preparation of flood
contingency plans and to provide advice during the emergency response process. In Ontario,
conservation authorities, and the MNR are responsible for forecasting where and when flooding is
likely to occur and issuing flood alerts and warnings to local municipalities, the media, police and
school boards. To facilitate this activity, conservation authorities and the MNR work closely with
Environment Canada, Meteorological Services, who provide the weather information necessary to
make the flood forecasting systems function effectively.
These advance warnings allow municipalities and other government agencies to put emergency
response plans into operation, to evacuate communities and remove portable property from floodsusceptible areas. Advance warnings also notifies the public of developing or ongoing unsafe
river and lake conditions, and allows them to take precautions.
There are four different flood messages:
FLOOD ADVISORY: notifies that the potential for flooding exists within specific watercourses and
municipalities.
FLOOD WARNING: notifies that flooding is imminent or occurring within specific watercourses
and municipalities.
FLOOD SAFETY BULLETIN: notifies that unsafe lake, river and channel conditions exist.
WATERSHED CONDITIONS BULLETINS: notifies of anticipated watershed conditions.
In Ontario, the flood risk area is defined by the flooding hazard limit. Depending on location in the
province, the flooding hazard limit is determined by the 100-year peak flow, a regional storm or
the highest observed flood. In some communities, the two-zone approach is used, with a
floodway and flood fringe being designated. Ontario has over 270 communities that are
'designated flood areas'. Is your property in a 'designated area' that is subject to recurrent and
severe flooding? Find out at www.ec.gc.ca/water/en/manage/flood/e_ont.htm
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"The first barrier to the contamination of drinking water involves protecting the sources of
drinking water."
— Justice Dennis O'Connor, Walkerton Inquiry 2002
Water quality initiatives have become more prominent with the water contamination in Walkerton,
Ontario. Reports following the Walkerton tragedy, included recommendations made to the
government that conservation authorities take the lead in source protection planning — the
government has agreed to implement all of the Walkerton Inquiry recommendations.
Water is critical to all aspects of our lives and it is important that we ensure there is a safe and
reliable source of water for all our uses — now and in the future. Our drinking water comes from
lakes, rivers, streams or underground sources (aquifers) located across the province. All of these
sources of water are linked in a watershed through the water cycle.
Efforts are ongoing to develop source protection plans for each watershed in the province. This
includes managing Ontario's rivers and other water courses on a watershed basis where we
realize that everything is interconnected; the human and natural impacts affect the water quality.
Conservation authorities are the only watershed management agencies in Ontario that are
organized on a watershed basis. Since Hazel, the role of conservation authorities has grown to
include the protection, management and restoration of Ontario's waters, woodlands, wetlands
and natural habitat; the development of programs that will protect life and property from natural
hazards such as flooding and erosion; and the delivery of environmental education to the public
to ensure our environment is protected for future generations.
"Green roofs" are a new idea of growing plants in soil on
flat rooftops, which store rainfall, serving to reduce floods. York University.
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Facts at a Glance
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Conservation authorities are local, community-based environmental organizations that
manage natural resources on a watershed basis across Ontario. Conservation authorities were
created over 55 years ago under the Conservation Authorities Act.
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The conservation authorities of Ontario own more than 340,000 acres (138,000 hectares)
of land, serving a population of more than 10,000,000.
The conservation authorities of Ontario have over 350 conservation areas in the
province, and more than 200 of these areas offer a wide range of recreational activities and
facilities.
132,771 acres of conservation lands are available for recreation.
More than 6,000,000 visitors each year visit the conservation lands.
More than 1,500,000 campers each year use the 60+ campgrounds.
Conservation authorities are the only agencies set up to manage renewable natural
resources on a watershed basis.
Conservation authorities are independent, local agencies made up of representatives of
member municipalities within the watershed.
Through strong partnerships, conservation authorities work with provincial ministries,
local municipalities and other community organizations.
Because conservation authorities are local, they are responsive to community needs.
They also have the flexibility to adapt province-wide programs to suit the local situations.
Provincial legislation requires that only local communities can initiate a request to
establish a conservation authority.
In practice, conservation authorities perform two essential services: control of water
quantity-flood control and protection of our natural resources. Supporting these services,
conservation authorities are responsible for a wide range of programs, including flood control,
dam maintenance and floodplain planning; soil erosion and reforestation; watershed
management, and the provision of conservation areas and public education. This work
improves our quality of life by actively providing open space and recreational opportunities.
Conservation authorities provide technical advice to municipalities in the review of land
use and development plans.
In its more than 50-year history, the conservation movement has pioneered local
environmental protection initiatives.
If you are interested in getting involved in environmental initiatives in your community, please
contact your local conservation authority below.