Flooding and Erosion
One role of water is to help shape and form the landscape. As water moves across the land, it erodes, transports, and deposits materials and sediments.
Many natural processes can affect our water. When we think of environmental pollution, we often think of chemicals from industry and car exhaust. Erosion and flooding are two processes that shape our freshwater lakes, rivers, and streams.
What Impact Does Erosion Have On Water Quality?
Erosion occurs naturally over hundreds of years. But our choices can hasten it. Humans often remove shrubs and trees near and on stream banks, allow livestock into streams, and plant fields and gardens close to streams.
All of these activities decrease bank stability. As a result, more sediment enters the water. The sediment often adds nutrients to the water, which harms its quality.
Flooding is a natural process that affects water. Flooding of the Lake Winnipeg watershed is often caused by:
The wet ground in the fall
Severe winter cold, which causes deep frost
Heavy snowfall, especially during the last half of winter
A late spring with sudden warming
High rain or snowfall during the spring melt
What Causes Flooding?
Environmental Impacts on Water
Large amounts of water flow over the land and into the ditches, creeks, rivers, and streams into our lakes. Flooding and excess runoff from rain and snowmelt can cause an inflow of nutrients, pollutants, and other materials to enter our waters.
Flooding can lead to eutrophication, which happens when there are too many nutrients in the water. High and low water cycles in our watershed affect nutrient availability and growing conditions.