2008 Watershed Report Card
Marshes, swamps, bogs and fens are all different types of wetlands. Each subwatershed was graded based on the percentage of wetland cover in the area; the higher the percentage the better the grade.
Wetlands are a very important part of the natural ecosystem and the water cycle. They provide habitat for plants and animals, and act as filters by removing sediment, nutrients and bacteria from water that travels through them. Wetlands also provide natural flood control, acting like a sponge to absorb water. They release water over a longer period of time, instead of all at once.
Many wetlands are located throughout the watershed due to low gradients and the slow, sluggish nature of our watercourses. Within our watershed, there are 57 provincially significant and 48 locally significant wetlands, shown on the map in black.
Our watershed received excellent grades for wetland cover. The geographic features within our watershed, both the rolling hills and the flat areas between hills, promote natural wetland cover. The result is a very high overall average.
There is still a need, however, for improving and protecting existing wetland cover. Our wetlands are under pressure from increasing urban development and agricultural production. This report card gives us a starting point that we can use in the future to monitor decreasing or increasing amounts of wetland cover.
Wetlands fall into four broad categories:
Marshes – Are the most common type of wetland, almost always flooded with shallow waters usually less than 1 metre in depth. Marshes often have water flowing through them. They contain plenty of vegetation, such as floating plants, cattails, and reeds, which provide good habitat for birds. Marshes are among the most productive ecosystems in the world.
Swamps – Are most often flooded at some point throughout the year. They are very productive, and have high levels of oxygen, nutrients and decomposers. They also contain at least 30% tree or shrub cover.
Bogs – Are very low in nutrients due to their dependency on rain water. They support a unique ecosystem dominated by peat and sphagnum moss, which tolerate a low pH, or acidic, environment.
Fens – Support a wider variety of plants and animals than bogs, including wildflowers and some trees such as tamarack.