Erosion is defined as the natural breakdown and movement of soil and rock by water, wind, or ice.
Human activity can speed up erosion, especially if vegetation on the banks and surrounding areas of streams is removed. When this happens, large amounts of sediment (soil, sand, and other fine particulates) are washed into the stream. Once in the stream, these sediments can have several adverse effects:
“Suspended” sediment, or sediment that has not settled out, reduces light penetration to the bottom but also can absorb the sun’s energy and warm the stream. Warmer water holds less oxygen and can kill fish once a critical level is reached (for some coldwater species like Bull Trout, temperature stress starts to occur around 16˚C). Sediments can also irritate or damage fish gills, and this can even lead to death.
Settled sediment still causes issues, burying and smothering fish eggs or burying gravel and cobble habitat, which is very important for invertebrates and other bottom-dwelling critters. If enough sedimentation (accumulation of sediments) occurs, it can even change the course of a stream or cause the stream to spill over its banks.
Restoring stream banks and helping to mitigate stream bank erosion are among the many projects TUC leads to protect and conserve freshwater systems.
A few things that you can do to help:
If your property backs onto water, leave a buffer of native vegetation between the water and your lawn.
Reduce hard surfaces that promote water runoff (driveways, concrete pads, etc.) and use materials that allow the water to enter the soil.
Plant native vegetation.
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