Skip to content
Stream with healthy riparian area

What’s a Riparian Area?

Healthy riparian areas are the interface between land and water, characterized by deep-rooted vegetation. Streambanks, floodplains, and wetlands are common examples of riparian areas. Due to their properties and functions, riparian areas are uniquely important for both land and water management.

Riparian areas are generally low-lying and adjacent to open water such as rivers, lakes, and ponds. Because they are low-lying, ground water is generally very near the surface and the soil tends to be fine, silty soils carried in from floods and runoff. Specific, water-loving plants, such as red osier dog wood and cotton wood trees, are characteristic of riparian areas.

Ecological Functions of a Healthy Riparian Area

As an analogy, you can imagine riparian areas functioning as a sponge, a filter, and a net.

A sponge: The soils and organic matter characteristic of a riparian area are very absorbent. You may have noticed this if you’ve ever walked along a flooded stream in spring. The ground itself can soak up water from the adjacent waterway. When a waterway is overfull, the excess can be absorbed by the riparian area. Then, when water levels recede, water is slowly released back. Much like a saturated sponge held in your hand, the water in a riparian area will re-enter the stream or lake over time. Through acting as a sponge, riparian areas can help prevent both flooding and drought by absorbing excess water then releasing it slowly over time.

A filter: As water runs across the ground and through a riparian area, it is also filtered. Much like a filter in a coffee pot, the fine soils, dense organic matter, and thick vegetation slow water down and catch eroded soils and pollutants. Runoff from roads, parking lots, agricultural areas, and industrial areas can contain pollutants which are filtered by riparian areas before they enter the adjacent waterway.

A net: Deep rooted vegetation is integral to a functioning riparian area because the root system acts like a net, holding the soil in place. If you’ve ever floated or fished a local river, you’ve likely seen an exposed bank with the root system holding it in place. Through this net of roots, riparian areas prevent substantial amounts of erosion. During high water events, the roots of riparian vegetation can also help keep shorelines, streambanks, and the surrounding human infrastructure intact.

In the Flathead Valley we are fortunate to have an abundance of clean water. Riparian areas are one of the key ingredients for it that way. So the next time you’re fishing, swimming, boating, or generally enjoying our local waters, remember to also appreciate our riparian areas – the silent sentinels that protect our water and our way of life.

Back To Top