Coromandel flood protection scheme service level review
Report: TR 2018/26
Author: Anderson Aimusu
About this report
Hydrological and hydraulic models of the Coromandel Township and its catchment was developed and used to model the flood levels for Whangarahi Stream, Karaka Stream and the Golf Course Drainage for a range of different return period events, under both current and expected future climate conditions.
The modelled flood levels was then used to assess the performance of the existing stop banks and floodwalls under design storm events. The results was used for the hydrological review, it is concluded that the Coromandel scheme stop banks and floodwalls meet to their design objectives. There could still be a potential risk of flooding in the lower reach of Whangarahi Stream and on the right bank of Karaka Stream near Kapanga Road. This flooding risk is highest when there is a combined high tide level at Coromandel harbour and high overflow from Karaka Stream.
|3.5||High intensity rainfalls|
|4.2.1||Channel cross sections and model network|
|4.3||Coupled One/Two-dimensional modelling|
|4.3.1||Digital elevation data|
|5||Service level assessment|