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The Oak Ridges Moraine is a landform unique to southern Ontario. One of Ontario's largest moraines, it 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. The rolling hills, 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.  The moraine is home to extensive natural and wildlife habitat for flora and fauna and provides exceptional recreational opportunities for people living in the region and the six million people who are within driving distance of this incredible landscape.


The Oak Ridges Moraine is more than just a beautiful landform feature with breathtaking vistas, rolling hills, wooded valleys and kettle lakes. Water, one of its most precious features, lies hidden below the ground surface sustaining the health of the many watersheds, which originate in the moraine and directly providing drinking water to over 250,000 people.


The moraine has been described as southern Ontario's rain barrel - its permeable sands and gravels absorb and collect precipitation, which slowly recharges 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. 


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 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. Strung along the rivers of the moraine are historic towns that show similar patterns of conurbation - the classic village center ringed by modern subdivisions 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 growing urban centers. Decades of restoration efforts to improve both aquatic and forest ecosystems are evident in wetland and river improvements and the addition of thousands of acres of forest lands. 

We have learned over the past 30 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. STORM and many other environmental organizations have successfully implemented strong land use controls. Yes, sprawl is encroaching at the southern front of the moraine and many issues remain including infrastructure development and a rapidly increasing population in the Greater Golden Horseshoe. These issues will drive the agenda of STORM over the next decades.

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