Buffers “lessen or moderate the impact of something”. When it comes to keeping our waterways healthy, buffers lessen or moderate the human impacts of construction, agriculture, and roads. They also lessen the natural impacts in the form of landslides, flood events, and fires on water quality.
A buffer is made up of a mat of trees, grasses and shrubs whose roots “glue” the soil along stream banks and also provide habitat for insects that ultimately end up as food for aquatic organisms. The vegetative buffers also provide shade which keeps stream channels cool.
The most prevalent and most harmful form of pollution in our streams is sediment or simply put, dirt. Dirt in our streams clogs the gills of aquatic organisms, covers rocks and cobble used for nesting and, in muck.
When the buffer (vegetation) is removed, the roots of plants no longer hold the soil and flowing water from the channel, or runoff from rainstorms, loosen the soil so stream banks collapse. Buffers not only help hold stream banks in place but they also act as a filter by slowing down surface runoff allowing water to soak into the soil.
Click here a list of plants that make good stream buffers.