King tide readers needed for Coast

A gauge, which could be set up on Orewa wharf this summer to record king tides is the latest step in a network that brings together the community and scientists.

The Auckland King Tides Initiative was founded by environmental scientist Ben Sheeran to gather information about the region’s king tides, which occur when the gravitational forces of the sun, Earth and moon align.

The project began in 2014, working with organisations such as Auckland Council’s coastal team and NIWA. Researchers and the community have been submitting photos to the initiative’s website and these have been catalogued.

Ben says the gauges, including the one proposed at Orewa Estuary wharf – which has been funded by the Hibiscus & Bays Local Board to the tune of $5736 – are the next phase in the process. The funding covers the gauge itself, website development and the data capture and mapping processes.

The use of gauges began in North Carolina. Looking like a large ruler, they are placed in the intertidal zone. The highest point of a king tide leaves a wet mark, which is read by members of the community and the data uploaded.

Ben says the research is especially important because king tides approximate what daily average tides will be like in the future due to sea level rise, within our lifetimes.

NIWA and Auckland Council coastal team will use the information to confirm the accuracy of the coastal inundation they have mapped.

Council has also begun putting out other gauges in the last 12 months, to measure tides.

Ben hopes that the community will get behind the project and encourages as many people to get involved in gathering the data as possible.

Any individual or business can take a reading and upload it to the King Tides website. Monitoring of the gauge does not have to be restricted to king tides.

This year there have been six king tides and the next one will be on Boxing Day. The Orewa gauge should be in place by then.

Info: Auckland.kingtides.org.nz