Erosion is defined as the wearing away of the Earth’s surface by wind, water, or glacial action.
Erosion and slope instability are two different processes which are often confused.
The erosion process affects the soil surface at the particle level, by gradually dislodging and removing the soil particles from the parent mass.
Slope instability consists of the sudden movement or sliding of a large mass of soil down an unstable slope.
This is a natural process in all rivers, streams, lakes, and coastal shorelines of the Great Lakes.
Erosion is a major hazard throughout many parts of the world. During the past 40 years about 30% of the world’s cropland had to be abandoned because of soil erosion caused by wind and water.
Erosion creates a variety of vulnerabilities in Ontario:
- Riverine and Valley Slope Erosion: It is the result of “fluvial processes” which are determined by the watercourse’s flow, and the sediment mixture of the watercourse bed and banks.
- Shoreline Erosion: Waves, currents, shore geomorphology, ice, and changes in the water levels bring about erosion. Shoreline erosion can result in deterioration of bluffs/banks, dunes, bearms, and beaches.
- Forest areas become vulnerable when all vegetation is removed from vast tracts by the lumbering industry or as a result of fire.
- Farming and crop cultivation expose large areas to the effects of wind and water on a seasonal basis for planting and harvesting.
The rate of erosion is sometimes accelerated as a result of flooding, or increased lake levels associated with changing land uses in the watershed, land drainage, climate change, etc.
MNR has the lead responsibility for managing in the event of water related erosion
