Beneficial Functions of Floodplains

Flooding is a natural function of a floodplain. People have been attracted to the Willamette Valley for many reasons related to the benefits provided by floodplains. Our rivers and floodplains have provided our community with transportation, industry, food, and recreation.

Floodplains are important for the natural storage and conveyance of flood waters. They protect water quality, recharge groundwater reserves, and preserve our local ecosystem. Natural floodplains reduce the severity and frequency of floods.

Examples of local floodplains include the West Eugene Wetlands preservation project, Delta Ponds and the bike paths along the Willamette River. Floodplains maintained in a natural state can slow stormwater runoff and help filter non-point source water pollution.

Natural Flood and Erosion Control

Over the centuries, floodplains develop their own ways to handle flooding and erosion with natural features that provide floodwater storage and conveyance, reduce flood velocities and flood peaks, and curb sedimentation. Natural controls on flooding and erosion help to maintain water quality. Floodplains do this by filtering nutrients and impurities from runoff, processing organic wastes and moderating temperature fluctuations. These natural controls also recharge groundwater by promoting infiltration and refreshing aquifers.

Biologic Resources and Functions

Floodplains enhance biological productivity by supporting a high rate of plant growth. This helps to maintain biodiversity and the integrity of ecosystems. Floodplains provide excellent habitats for fish and wildlife by serving as breeding and feeding grounds.

Societal Resources and Functions

Floodplains enhance the quality of life for those living and visiting our community, a role that can often be undervalued. Parks, bike paths, open spaces, wildlife conservation areas and the aesthetic features they provide are important to many citizens. Assets like these help make our community more appealing to potential employers, investors, residents, property owners and tourists.

Flood Hazard Information Assistance
The City of Eugene provides free information regarding flood hazards for specific sites within the community and can answer many of your flood-related questions. Staff can assist with flood protection and mitigation design questions and with local flooding concerns.