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  Services » Publications » Technical reports - by year » tr201238

Contaminants in Hamilton's urban stream sediments and ecotoxicity to amphipods

On this page: abstract, table of contents

Report: TR 2012/38

Author: SJ Clearwater (NIWA), T Valler (University of Waikato)


NIWA was commissioned by the Waikato Regional Council to survey contaminants in urban stream sediments in Hamilton and determine if sediment-associated contaminants are likely to inhibit restoration of these waterways.

The focus of the present study was on sediment associated contaminants. Dissolved or waterborne contaminant concentrations were not evaluated, however dissolved contaminants can significantly impact urban streams.

In June 2011 sediments were sampled at 27 locations in streams in the city of Hamilton and in May 2012 a subset of these locations was sampled again. Concentrations of up to 23 elements in stream sediments were compared.

Contaminants in Hamilton's urban stream sediments and ecotoxicity to amphipods (1mb)

Table of contents

  Executive summary 7
1 Introduction 10
1.1 Background 10
1.2 Site selection, contaminant analysis and toxicity testing 11
1.3 Comparison with sediment quality guidelines 11
1.4 Establishing current "background" concentrations and contaminant sources 12
2 Methods 14
2.1 Site locations 14
2.2 Sediment collection 17
2.3 Sediment analysis 17
2.4 Amphipod toxicity testing 19
3 Results and discussion 20
3.1 Grain size and organic carbon content 20
3.2 Sediment organochlorines and polycyclic aromatic hydrocarbons 22
3.3 Amphipod toxicity test 23
3.4 Sediment metals 2011 and 2012 24
3.5 Summary of guideline exceedance and amphipod results for each site 32
3.6 Peacockes tributary of the Mangkotukutuku Stream 37
3.7 Rukuhia and Te Anau tributaries of the Mangakotukutuku Stream 37
3.8 Normandy A and Graham A 37
3.9 Kirikiriroa catchment 39
3.10 Waitawhiriwhiri catchment 40
3.11 Bankwood Park and Parana Park 41
3.12 Ranfurly 41
4 Conclusions 43
5 Acknowledgements 44
6 References 45
  Appendix A: Sediment contaminant concentrations 47
  Appendix B: Sediment metal concentrations 68





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