Durham Region has an area of 258,134 ha. The environmental setting is very similar to that of the Region of York. The lands immediately north of Lake Ontario are heavily urbanized (the Towns of Ajax and Whitby, the Cities of Pickering and Oshawa, and the Municipality of Clarington). The few undeveloped shoreline areas are occupied by provincially significant coastal marshes (e.g., Frenchman's Bay, Lynde Shores, Oshawa Second Marsh) that are fully protected (Level 1) within the Durham Official Plan (Figure 7).
Durham Region's Official Plan identifies a Major Open Space System (MOSS) that includes Open Space Linkages and Waterfront Links, and a Permanent Agricultural Reserve in north Pickering (Table 6). These partially protected (Level 3) areas occupy much of the undeveloped land between Pickering and Whitby and Oshawa and Bowmanville (Figure 7).
Although the section of the Oak Ridges Moraine that passes through Durham is somewhat narrower than in York, this landform occupies much of the central portion of the Region. Much of the Moraine is heavily forested, with Level 1 protection given to these woodlands (Figure 7).
Between the south edge of the moraine and the present urban limits of Ajax, Whitby and Oshawa lies the Lake Iroquois Shoreline. This is a ridge of sands and glacial lake deposits (silts and clays) that marks the shoreline of Lake Ontario (glacial Lake Iroquois) left behind after the last glaciers melted 10,000 to 12,000 years ago. It performs an important groundwater recharge/discharge function, providing baseflow to the many Level 3 creeks and rivers (Level 3 ESAs and valleylands) that flow south to Lake Ontario (Duffins, Harmony, Oshawa, Lynde, Wilmot and Ganaraska), and supports a number of Level 1 wetlands and Level 2 woodlands (Figure 7). Much of the agricultural land immediately north and south of the Moraine has little forest cover and these small, remaining woodlands are generally not protected (Level 4) under the Regional Official Plan (Region of Durham 1994).
That portion of Durham Region lying north of the Oak Ridges Moraine (Town of Uxbridge and Townships of Brock and Scugog) is traversed by a series of wide, Level 3 creek valleys (e.g., Uxbridge Brook, Pefferlaw Brook, and Nonquon River) that drain north to Lake Simcoe. These north-south trending lowlands contain provincially significant swamp forest wetlands (Level 1 protection), within which development is prohibited. The land use in north and northeast Durham is predominantly rural, within which most of the smaller woodlands are not given any policy protection (Level 4). Another rural area is the Duffins Rouge Agricultural Preserve and the Seaton lands, both in the Town of Pickering.
Due to the relatively large portion of the Region within the Oak Ridges Moraine, it has a relatively large portion of Level 1 protected lands - 16.2%. The Regional Major Open Space System also contributes a relatively large portion of the land with Level 3 protection - 21.6%.
Table 6: Levels of Greenlands Protection for the Region of Durham
Figure 7: Regional Municipality of Durham