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Assessing erosion in the Waipa catchment using the New Zealand Empirical Erosion Model (NZeem®), Highly Erodible Land (HEL), and SedNetNZ models

TR 2013/54

Report: TR 2013/54

Author: D Palmer, J Dymond and L Basher (Landcare Research)

About this report

Landcare Research was funded by Waikato Regional Council (WRC) to undertake an analysis of the Waipa catchment to identify high-risk areas of hillslope sediment generation, high-risk areas of stream bank erosion, and undertake an assessment of the work required to reduce suspended sediment loads in the river and stream network.

Objectives

  • using the Highly Erodible Land (HEL) model, evaluate high risk areas of hillslope sediment generation
  • using NZeem®, provide a quantitative analysis of where sediment in rivers is sourced
  • assess stream bank erosion using the SedNetNZ model
  • undertake simulation/scenario modelling to assess reductions in sediment loads through potential mitigation strategies.

Read or download the survey report

Assessing erosion in the Waipa catchment using the New Zealand Empirical Erosion Model (NZeem®), Highly Erodible Land (HEL), and SedNetNZ models [PDF, 3.8 MB]

Contents
  Summary
1 Introduction
2 Background
Objectives 
Methods 
4.1 Highly Erodible Land (HEL) 
4.2  New Zealand Empirical Erosion Model (NZeem®) 6
4.3 SedNetNZ Model 
4.4  Scenario modelling for stream bank erosion  13 
4.5 Waipa River and tributaries sediment collection  14 
5 Results and discussion  14 
5.1 Highly Erodible Land (HEL) model 14
5.2 New Zealand Empirical Erosion Model (NZeem®) 20
5.3 SedNetNZ and stream bank erosion 25
5.4 Waipa River and Waipa tributary sediment profile characters 27
6 Conclusion and future work 29
7 References 30