The Moraine
The Oak Ridges Moraine is a landform unique to southern Ontario.
One of Ontario's largest moraines, the Oak Ridges Moraine
extends 160 kilometres from the Niagara Escarpment in the
west to the Trent River system in the east, and is on average
13 kilometres wide. One-hundred-and-fifty metres deep, the
moraine stands out as one of the most distinct landscapes
of southern Ontario. Its height above the flat lands to the
north and south, its rolling hills and river and stream valleys
and large blocks of mixed forest provide solace and a sense
of connection to the people who live, work and play on the
moraine, natural and wild habitat for flora and fauna, and
untapped recreational opportunities.
However, the Oak Ridges Moraine is more than just a beautiful
landform feature with its breathtaking vistas, rolling hills,
wooded valleys and 'kettle' lakes. Its most precious feature
lies hidden below the ground surface.
One of the moraine's most important functions is as a water recharge/discharge area - sustaining the health of the many watersheds, which originate in the moraine and directly providing drinking water to over 250,000 people. It has been described as southern Ontario's rain barrel - its permeable sands and gravels absorb and collect precipitation, which slowly recharge the deep aquifers below the ground.
These sand and gravel aquifers store, filter and release
this groundwater to over 65 watercourses flowing north and
south into Georgian Bay, Lakes Simcoe, Scugog, Rice and Ontario.
At the same time, unprecedented human exploitation of this
groundwater places the moraine in a precarious ecological
position.
The 1991 Oak Ridges Moraine Planning Study, which began as
a tightly focused land use planning exercise, became a catalyst
for innovative water resource studies. The Ontario Ministry
of Natural Resources, through the planning study, undertook
a broad hydrogeological review of the Oak Ridges Moraine.
This led to the involvement of the Ontario Geological Survey
and the Ontario Ministry of the Environment in developing
detailed geological and hydrogeological mapping. In 1993,
the Geological Survey of Canada initiated an extensive five-year
Oak Ridges Moraine study. The result of this collaborative
work is an extensive 'regional scale' understanding of the
Oak Ridges Moraine, exceptional by Canadian standards.
Despite the focus of the Geological Survey of Canada and
its call for integration of land- use planning and groundwater
management, municipalities and the provincial government continued
to carry on with business as usual - processing applications
for development and official plan amendments in the absence
of a comprehensive groundwater management strategy. Land-use
changes, primarily the building of residential subdivisions,
the construction of roads and the paving of parking lots increase
the imperviousness of the ground surface, stopping water from
entering the hydrologic cycle. Consequently, this surface
runoff results in dramatic increases in wet weather flows
of the headwater streams on the moraine causing erosion and
degradation of these fragile systems. Urban and rural contaminants
entering the ground today can remain undetected for many decades
given the excruciatingly slow movement of water through the
ground. Water-taking, associated with these new land uses,
further exacerbates the pressure on the resource. Not only
is precipitation blocked from entering the ground but more
water is being removed. Municipal water supplies, golf courses
and commercial water-bottling companies have, by necessity,
began to 'go deeper' into the moraine to find adequate quantities
of drinkable and usable water.
 We have learned over the past several years that we must
proceed cautiously - how we use the moraine's land surface
and its water resources can affect the deep regional groundwater
flow systems, which are integral to the ecosystem health of
south-central Ontario.
The Oak Ridges Moraine:
A Provincial Treasure
Soaring north from Lake Ontario's northern shoreline, the
landscape below leaves behind the tall office buildings and
dense residential streets of Toronto's heart, passes over
suburban sprawl of subdivision and industrial parks and development
coalesces along major roads and unseen pipelines that penetrate
the countryside. The land below is flat, dissected by river
valleys that deepen as they reach further into their headwaters.
And then, abruptly, the country changes from flat till plains
to rolling hills and valleys; splashes of green forests and
blue waters replacing the greys and blacks of pavement and
rooftops. With a shift in perception through the lens of time,
you can almost see the massive glacial rent in the ice sheet
filling up with icy waters and a millennia worth of sand and
gravel and boulders; these are the early days of the interlobate
Oak Ridges Moraine, arcing like a huge eyebrow above the eye
of Canada's largest city.

Seen directly from above the first and most startling impression
is "this is where the rivers begin!" All along the
ridge of this regional surface water divide are many finger
patterns of tiny headwater streams bubbling out of the ground
in seeps and swales and springs. These trickles of water join
forces, delivering cold clean water to the many rivers and
streams that flow north and south from the moraine. The river
valleys are well forested, providing living corridors along
which animals travel. Wetlands and kettle lakes along the
length of the watersheds are home to hundreds of species of
birds and amphibians and provide needed watering holes for
all kinds of wildlife.
Deep within the ground is the true treasure of the moraine
- thick layers of sand and gravel many hundreds of metres
from surface to bedrock. The waters in these aquifers span
thousands of years in age; on the surface the water was yesterday's
rain but deep deep down the water held in trust was once glacial
ice. This is truly the lifeblood of the region, providing
water to people, to rivers and to the oceans. It is these
waters that may help us survive the warming of the years to
come.
 Strung along the rivers of the moraine are historic towns
that show similar patterns of conurbation - the classic village
center ringed by modern subdivisions and schools and baseball
diamonds. Up or downstream are remains of dams signifying
how important the fast flowing rivers once were to the economy
of a century ago. Today, the millponds perform a different
role of attracting birds and wildlife, bringing eco-tourist
dollars to these struggling centers.
The second startling impression is the sight of a long and
narrow urban band stretching from the south to the north straight
through the hills and valleys. The Big Pipe decision decades
ago helped to bury the precious tributaries under acres of
pavement and to bring thousands of people up to the moraine.
It was here where the moraine was almost cut in half by development
and it was here where the battle for the moraine was staged
and won. Through provincial intervention, this significant
section of the moraine has been placed in the public trust,
thus preserving a vital link in the regional natural heritage
system.
 Fields of corn, hay, soybean, horses and cattle seem to drape
themselves around large garrulous old forests. Decades of
restoration efforts to re-connect the forest fragments are
evident in the thousands of acres of pine plantations, the
hedgerow artifacts and the newly planted saplings put there
by school children. It's obvious now that many of these marginal
farm fields high on the ridge should never have been cleared
back in the early days of First Contact - like long lost friends
the newly-planted roots re-secure the fine sands and silts
and hold them close. More productive farms on the north and
south slopes are thriving and contribute strongly to the economy
of the area - tractors move more slowly up and down the moraine
hills than they do on the flat fields to the north and south.
The natural curves of the rivers and forest edges are rudely
pushed aside by the long linear slashes of roads first built
to bring the Europeans to this land to conquer. Like ribbons
of death, the new four lane highways do their best to stop
the genetic movement of nature. But nature's resiliency proves
too strong as plants and animals continue to move about the
length of the moraine.
Yes, sprawl is nibbling at the southern front of the moraine
and sprawl has been temporarily tamed. It will roar again
in the future and its threat will never totally disappear.
But for now development has been beaten back to the boardroom.
Debbe Crandall
STORM Coalition (Save the Oak Ridges Moraine)
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