Why We Map

Why We Map


Why We Map Currently, most municipal maps depict watercourses that have been identified and delineated based on the interpretation of airphotos. Unfortunately, this method is prone to inaccuracies, such as the failure to accurately identify and map watercourses in forested areas. The two thumbnails below illustrate situations where watercourses were either mapped incorrectly (figure 1) or unmapped entirely (figure 2). Click on the thumbnails to see the full images. NOTE: If you have pop-up ad blocking software installed, these windows may not appear.

			The result of these inaccuracies is the inability of municipalities or senior agencies to protect streams from human impacts. For example, a developer may seek a permit to clear land and build factories or high-rises on it. A common condition of obtaining such a permit is that the development will not impact salmon habitat.
	Figure 1	Figure 2

If, however, the maps don't contain information on any watercourses on the property, the permit can be freely obtained. Given the inaccuracies of many watercourse maps based on airphoto interpretation, it is entirely possible that the property may contain a tributary with important spawning grounds or winter rearing habitat; the failure to identify this on the maps might logically result in its destruction. More information on why we map can be found on the Sensitive Habitat Inventory and Mapping website. Mapping & Inventory \| Why We Map \| How We Map \| Where We've Mapped