Casting the dye: Cape Town and NSRI partner in ‘cutting edge rip current experiment’

Cape Town has partnered the National Sea Rescue Institute (NSRI) in a research project to study rip currents.

The experiment, which will use a non-toxic fluorescein dye to expose the flow of rip currents and help with beach safety education, will be carried out in False Bay and Table Bay. The NSRI’s  drowning-prevention team and the city’s recreation and parks department aim to develop “educational content based on aerial footage”.

Councillor Zahid Badroodien, the mayoral committee member for community services and health, waxed lyrical about the research.

“In a first for Cape Town, a research permit has been issued by the national department of forestry, fisheries and the environment for the deployment of a dye that will highlight and visually expose the flow of rip currents in the ocean,” said Badroodien.

“The dye is non-toxic to the environment and people. The footage captured will be used as part of a focused rip current/beach safety public awareness campaign as preparations for the summer season get under way.

“The NSRI has been granted the permit to deploy the fluorescein dye, according to global best practice among ocean researchers. Fluorescein is commonly used by scientists and plumbers in different water tracer experiments, as well as by carp fishermen, and is harmless. The first dye release took place last month at Kogel Bay and after studying the results from this experiment, the second release — which will be filmed — will take place at Strand beach.”

 Badroodien added: “Using the SA Weather Service’s experimental rip current forecast model, along with their standard operational coastal forecast systems, the rip current research team identified a strong likelihood for rip currents to occur on Wednesday October 20.” 

Badroodien said rip currents “can be deadly, as panicked swimmers often try to counter them by swimming straight back to shore, putting themselves at risk of drowning because of fatigue”.

“One of the top reasons for drownings at our beaches is swimming where there are no lifeguards present. The absence of lifeguards is the first indicator that it isn’t safe to swim there,” said Badroodien.

“Aside from emergency rescues, city lifeguards work closely with the NSRI to examine the surf and determine the safest swimming beaches. Only beaches where the red and yellow flags are put up and where lifeguards are on duty are deemed safe. Outside those areas, the coastline can be deceptively attractive for bathers looking for a quiet spot or secluded area to swim. In many instances, the surf is unsafe and bathers can quickly lose their lives in the unfortunate event that they get caught in a rip current.”

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