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Suspended sediment time trends in the Waipa River and Waitomo Stream

TR 2012/33
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Report: TR 2012/33

Author: J Hoyle (NIWA)

Abstract

Waikato Regional Council commissioned NIWA to assess the Waipa River at Otewa dataset for evidence of a trend or change in sediment yields that can be related to catchment and bank recovery works.

It then became apparent that there are also concerns regarding trends in sediment yields in the Waitomo catchment, so an assessment of trends in the Waitomo catchment was added to the scope of this study.

Suspended sediment time trends in the Waipa River and Waitomo Stream [PDF, 937 KB]

Contents
1 Introduction 4
1.1 Background 4
1.2 Drivers of changes in suspended sediment concentration 4
2 Methodology 10
3 Results and discussion 13
3.1 Waipa 13
3.2 Waitomo 15
4 Conclusions 18
5 Acknowledgements 19
6 References 19
  Appendix A : Plots of residuals over various time for testing time trends 20