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The effect on Waikato river water quality of changes to river flow and catchment land use, including the December addendum

TR 2005/03
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Report: TR05/03

Author: Kit Rutherford (National Institute of Water & Atmospheric Research Ltd)

Abstract

Environment Waikato has requested NIWA to predict the likely effects on Waikato River water quality of:

1. reductions in the flow of the river at times of low flow; and

2. changes in nutrient loads to the river from dairy conversions;

by making use of an existing Waikato River water quality model (Rutherford et al. 2001). Results are provided in this report. Appendix 1 contains the contract details.

Originally 10 scenarios were detailed for modelling but subsequently an 11th scenario was requested (Appendix 2). Email correspondence to clarify assumptions made in these scenarios is attached (Appendix 2).

Subsequent to the presentation and acceptance of this report, EW requested that we run the model for 5 additional scenarios (cases 12-16). These are presented as an addendum in section 4.

The effect on Waikato River water quality of changes to river flow and catchment land use, including the December addendum [PDF, 598 KB]