Models to help manage erosion

Managing land erosion, and subsequent sedimentation in streams, lakes, and coastal areas, is a big headache for many local authorities.

At two recent workshops, NIWA and Landcare Research joined with land-use managers to explore ideas of how computer models might help resolve some of the issues faced. Major environmental problems identified included estuarine infilling, pasture and soil degradation, sediment affecting water quality, and fine sediment altering stream-bed habitat. Participants concluded that a suite of models is needed to address the issues, and the following priority areas were agreed on:

  • Urban earthworks erosion risk and management
  • Farm management plans for erosion management
  • Forest block erosion management
  • Linked models of catchment sediment loss and receiving environment, especially estuaries
  • Erosion rate/risk at large catchment or regional scale
  • Management of gravel extraction in gravel-bed rivers
  • Assessment of the intrusion of fine sediment into stream beds

The ideas from this workshop will guide further research by NIWA, Landcare Research, and regional council partners. A report, has been prepared based on the workshop, and can be downloaded below:

Sediment model workshop report (PDF 4.1 MB)

Fine sediment runoff, Kaipara. [NIWA]