On 25 July 2017, the elected Council adopted a strategic position paper (the Paper) to protect the low lying areas from future flood risks associated with climate change. The Paper includes a list of actions (phase 1 -6) that are triggered if increments of sea level rise are recorded. Phase 1 was triggered upon adoption of the Paper and requires sea and groundwater level monitoring.
In relation to sea levels, City of Newcastle has worked with the Department of Planning, Industry and Environment (DPIE) to establish a benchmark and methodology for the measurement of mean sea level rise. The Paper has set the benchmark based on mean sea level at time of its adoption.
City of Newcastle and DPIE have since investigated the behaviour of sea levels. DPIE has recommended using the Fort Denison tide gauge in Sydney for the monitoring because, not only is this the longest publicly available record in the southern hemisphere, but more importantly the site holds data of the highest accuracy in NSW. There is not reported to be any difference in sea level rise between Sydney and Newcastle.
When analysing the data from 1990 to 2017 it was found that the mean sea level has risen by approximately 3cm or 0.032m. This indicates sea levels are rising slowly, and it indicates that there is at least 10 to 25 years until the 0.1m trigger (Phase 2) is reached. Phase 2 requires installation of improved flood gates and drainage outlets, high powered pumps, and the design of the levee for construction in Phase 3 (0.2m sea level rise).
In relation to groundwater, wells have been installed in March 2018 and a long term groundwater monitoring program will commence to better understand groundwater behaviour in the study area.