Analysis of Whitianga, Tararu, Kawhia and Manu Bay sea level records to July 2024

Waikato Regional Council operates sea-level gauges at Tararu, Whitianga, Kāwhia, Raglan and Manu Bay. Digital sea-level records began at Tararu in 1990 and at Whitianga in 1999, with the other gauge records beginning 2008.

NIWA were engaged to analyse the sea-level records. The primary focus was on examining mean sea-level change, tidal heights, and extreme events within the sea-level records to elucidate the localized dynamics of storm-tides in relation to tides and meteorological conditions.

This report offers diverse sea-level analyses pertinent to coastal planning, regulatory efforts, hazard assessment, and is applicable across the five sea-level records.

Report: TR 2025/23

Authors: Glen Reeve (NIWA)