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Kaihu Flood Control Scheme Investigation - Stage 1 and 2

The purpose of Stages 1 and 2 of the Kaihu flood control scheme investigation was to establish a base case of flooding under existing conditions in events of 2, 5, 10, and 100 year average recurrence interval, against which the effectiveness of proposed flood control measures could be assessed.

Report Table of Contents

1. Executive Summary

2. Introduction
2.1 Scope
2.2 Background
2.3 Site visit
2.4 Source data
2.5 Software

3. Hydrology
3.1 Flood frequency analysis
3.1.1 Flow data
3.1.2 Peak discharge distribution
3.1.3 Flood volume analysis
3.1.4 Historical return periods
3.2 Design floods
3.2.1 Hydrograph shape
3.2.2 Hydrograph size
3.2.3 Ungauged catchment hydrographs
3.3 Historical calibration floods
3.4 Tidal record analysis
3.4.1 Calibration event tides
3.4.2 Design event tides
3.4.3 Storm surge and river floods

4. Hydraulic model
4.1 Hydraulic model construction
4.1.1 Overview
4.1.2 Kaihu River
4.1.3 Floodplains
4.1.4 River banks, stopbanks, and other embankments
4.1.5 Boundary conditions
4.2 Calibration of hydraulic model
4.3 Existing case simulations
4.4 Flood mapping

5. Conclusions and recommendations

6. References


Appendix A Model files
Appendix B Figures and plans
Appendix C Flood Maps
Appendix D Kaihu River cross sections
Appendix E Floodplain branch details
Appendix F Hydraulic model boundary conditions