Natural Floodplain Functions

The floodplain function in the Sioux Falls area can be summarized in the following categories from A Unified National Program for Floodplain Management, 1994, p.41: 

Water Resources: 

  • Natural flood & erosion control,
  • Provide flood storage and conveyance,
  • Reduce flood velocities,
  • Reduce flood peaks,
  • Reduce sedimentation,
  • Surface water quality maintenance,
  • Filter nutrients and impurities from runoff,
  • Process organic wastes,
  • Moderate temperature of water,
  • Groundwater recharge
  • Promote infiltration and aquifer recharge,
  • Reduce frequency and duration of low surface flows.

Biologic Resources 

  • Biological productivity,
  • Support high rate of plant growth,
  • Maintain biodiversity,
  • Maintain integrity of the ecosystem, 
  • Fish and wildlife habitats,
  • Provide breeding and feeding grounds,
  • Create and enhance waterfowl habitat,
  • Protect habitats for rare and endangered species.

Societal Resources 

  • Harvest of wild & cultivated products,
  • Enhance agricultural lands,
  • Provide sites for aquaculture,
  • Restore and enhance forestlands,
  • Recreational opportunities,
  • Provide areas for active and passive uses,
  • Provide open space,
  • Provide aesthetic pleasure,
  • Areas for scientific study and outdoor education,
  • Contain cultural resources (historic and archaeological sites),
  • Provide opportunities for environmental and other studies,

The City has different policies to help with different aspects of these areas, but the floodplain program implemented the compensatory storage requirement to address many of these issues, while our parks department has provided great open space and natural areas along City waterways. In addition, the Engineering Department has provided many new areas for collection, saturation, and through more natural maintenance techniques, natural filtration of water before it enters the stream.