With more people on the beaches over the festive season NSRI are urging the public to be extra cautious between now and the New Year with the New Moon Spring Tide, which peaked yesterday, that will cause stronger than normal rip currents around the coast.
Spring Tide happens twice every month, at full moon and at new moon.
Spring Tides bring a higher than normal high tide and a lower than normal low tide, causing stronger than normal rip currents, for a few days leading up to the full moon OR new moon, peaking on the day of the full moon OR new moon and lasting for a few days after the full moon OR new moon.
There are two high tides and two low tides every day. During Spring Tide the twice daily high tides are higher than normal and the twice daily low tides are lower than normal and while rip currents are always present and dangerous the Spring Tide creates stronger than normal rip currents and hence the danger is increased.
Rip Currents are caused when the water reaching the shoreline in waves, swells and sea currents needs to find a way to retreat back into the sea and this is achieved in rip currents (a river of water retreating through the incoming swells back out into the sea).
There are two types of rip currents, permanent rip currents, found alongside islands, rocky outcrops jutting into the sea, at river mouths, in between reefs and alongside harbour walls and piers, are found constantly occurring in the same place allowing the water reaching the shoreline to retreat back into the sea in the permanent rip current. Temporary rip currents, found along beach fronts (along the shoreline), are forever changing their position and are unpredictable and can form suddenly along a beach front without warning at different places along the shore front throughout the day.
During Spring Tide these permanent rip currents and temporary rip currents are stronger than normal and although rip currents at all times pose a danger to bathers they pose the greatest danger during the Spring Tide.
Bathers are at risk of being swept out to sea by rip currents while swimming or wading in water along the beach front. Even bathers wading in shallow water who find themselves trapped in a rip current that forms suddenly are at risk of being swept out to sea by rip currents.
Bathers caught in a rip current should not panic. Simply stay afloat by treading water (moving your arms and legs in circular movements), don’t try to swim against the current as it will only cause you exhaustion and let the current sweep you out to sea but at your first opportunity swim parallel to the beach front until you are free of the rip current and then use the incoming waves to get back to shore.
While this is happening scream for help and wave your arm to alert people on the beach to raise the alarm.
Swim at beaches where lifeguards are on duty and obey the instructions of the lifeguards and only swim within the safe swimming zones lifeguards mark (using their red and yellow flags).
Children should have responsible adult supervision at all times around coastal and inland waters and at swimming pools.
Anglers fishing along the shoreline, particularly along rocks on the shoreline, are at greatest risk during the Spring Tide where incoming waves during the high tides engulf higher than normal over rocks.
Anglers should not turn their back to the sea and should be vigilant and cautious of the wave action at all times while fishing.
NSRI have also circulated this video as a swimmer lesson on how to avoid rip currents...
Boaters, paddlers, sail boarders and anyone launching any kind of craft onto water should wear their life-jackets at all times while on water and carry easily accessible safety equipment – red distress flares, communications cellphone or VHF radio with fully charged batteries in water tight plastic sleeves, a waterproof torch, highly visible neon coloured clothing, a referee whistle worn around the neck, a silver emergency foil blanket, and let a responsible person know your time of departure, your exact intended route and your estimated return time, stick to your plans and check in with the responsible person on your safe return. (If you are overdue the responsible person should raise the alarm without hesitation).