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Flood
This is not the first flood, and certainly not the last.
Flooding started early on Wednesday, 30 March 1910.
In the 12 hours from 6.30 p.m. on Tuesday there was 12in of rainfall, while the fall for 16 hours from the time mentioned was rather over 14in [356 mm]. [1]
[1] https://paperspast.natlib.govt.nz/newspapers/NZH19100404.2.67
New Zealand Herald, Volume XLVII, Issue 14335, 4 April 1910, Page 6