Effects of estuary’s geometry and bathymetry on extreme water levels, study case: manukau harbour, new zealand

The present work aims to understand the potential effects of bathymetry and geometry on the total water level in Manukau Harbor in the present and future projections of sea-level rise. Our study site is in the southwest region of Auckland. The tide is mesotidal amplitude, and the estuary has a prismatic geometry, extensive tidal zone, and depths ranging from 30m (close to the estuary entrance) to 1m in the inner channels. We analyzed the observed total water level in 2 tide gauges. The first one, located outside the Harbor, is the Anawhata tide gauge — managed by the National Institute for Water and Atmospheric Research (NIWA) —; the second, located in the inner estuary, is the Onehunga tide gauge, managed by the Auckland Council. Our methods can be divided into two sessions, the data and numerical analysis.