A ground breaking traffic light system which uses a tide gauge to indicate when safest to cross a causeway is being trialled at Sully Island in Penarth.

With RNLI volunteers from Penarth regularly being called to assist people cut off by the tide, the RNLI’s Coastal Safety Team devised the pioneering warning system.

In 2013 the RNLI as a whole responded to 428 incidents of people being cut off by the tide and saved 109 lives. In Wales, there were 112 launches to people cut off, eight lives saved and 139 people rescued.

Sully Island is a popular place to walk and families regularly find themselves trapped and in need of RNLI assistance. The speed of the incoming tide can make crossing from the mainland to Sully Island dangerous and potentially life threatening. So by highlighting safe crossing times, the RNLI is hoping to reduce the number of incidents.

RNLI Community Incident Reduction Manager Nicola Davies says:

‘The rocky causeway which connects to Sully Island is only uncovered for three hours either side of low tide, which means that hundreds of visitors have been caught out over the years. Whilst RNLI volunteer crews are trained and ready to put to sea when people need help, we are keen to educate the public about potential hazards, so they are well aware of the dangers and don’t require assistance from the RNLI.

‘The sign is a pilot and has not been tested anywhere else in the UK. Sully Island is the perfect place for it to be tested as we are seeing regular incidents involving people cut off by the tide resulting in call outs for Penarth RNLI.

‘The tides around the island move very quickly so RNLI urge people visiting the island to check the tide times before they set out, and never ever be tempted to cross the causeway or swim across to the shore when the tide is coming in. By observing the sign, visitors don’t have to second guess how much time they have, and know exactly when it is safe to cross. We will be monitoring the impact this sign has throughout the season.’

The sign uses a tide gauge to indicate three phases - when it is safe to cross - when time is running out and when it is unsafe to cross the causeway. The tide gauge is able to sense how quickly the water is coming in. In the yellow phase, the sign provides a countdown as to how much time is left on the causeway. When the warning light displays red, it signals a warning that there may not be enough time to get back to the mainland.

The sign was developed with tide gauge experts Karlan Digital Ltd and is being supported by a local community partnership with Gordon Hadfield the owner of the local caravan park and Seashore Grill & Café.

The RNLI’s Coastal Safety Team is using Penarth as a pilot for the project and will be gathering data as to whether the project has been successful. If it is deemed to have cut down on the number of incidents of people being cut off by the tide, there is potential it may be rolled out to other problematic areas across the UK.