(July 20, 2018) If you spend anytime at the beach and listen to local television or radio at this time of the year, you will hear about the dangers of rip currents.
I get a lot of questions about what the difference between a rip current and a rip tide is and what makes them so dangerous.
You will see on local and national news coverage stories about rip currents. Although they are often mistakenly referred to as “rip tides,” they are in fact a current.
A current is simply a volume of water moving from one location to another. In contrast, tides are caused by the gravitational pull of the moon and sun and occur about every 12 hours.
What makes a rip current dangerous is that it moves water away from the beach and out to sea, where north or south currents (littoral current) just move water along the beach. As water flows away from the beach, in the rip, anything or anyone in that water will also be pulled steadily away from shore.
This action not only accounts for how unsuspecting bathers and people that never intended to go out further than their waist are pulled into water that is over their heads. It also is responsible for creating the telltale signs that identify a rip current to the trained eye.
As waves break and stir up the sandy bottom and create foam, this discolored water and foam are carried away from the shore clearly marking the location of a rip current.
While the mechanics of a rip current are easily understood, they still remain the greatest surf zone hazard for anyone enjoying water activities at any beach (80 percent worldwide) and account for 95 percent of all water related rescues in Ocean City.
Rip currents are such a well-known natural hazard that the National Weather Service has identified them as the third leading cause of weather related death. If you question the seriousness of this threat then just take a moment to realize that not all states could even contribute to this statistic because not all states have ocean beaches.
So being the third leading cause of weather-related death is quite significant. Already this summer there have been dozens of rip current drowning around the US as well as in the Great Lakes. Yes, even the Great Lakes has rip currents.
To understand how to escape a rip current it is important to understand what causes rip currents.
Rip currents occur when water that comes into the beach by wave action and wind needs to make its way back out. Because a sand bar runs the length of Ocean City, water that has come over the sand bar needs to make its way back out.
Because wave action continues to bring water over the sandbar, the water has difficulty going out against the incoming flow. Water will take the path of least resistance and find a lower spot along the sandbar to become the natural path for the flow of the water.
As more water comes across the sandbar the volume in the trough (water trapped between the beach and sandbar) increases and this additional volume of water causes an increasingly greater volume of water to flow through this path.
As water flows along this path it will move sand and creates a deep underwater channel from the shoreline through the sandbar. As waves break near the beach they cause a change in bathometry (the contour of the ocean bottom), which causes a constant change in the sandbar and thus rip current locations and severity are constantly changing.
Rips can open up at any given time, sometimes referred to as “Flash Rips.” Just last week I was out swimming and I could see little rips opening up where just minutes before there weren’t any in the area where I was swimming. It was a rough choppy day and the sandbar was being broken away.
Another factor that has an influence on the frequency and severity of rip current activity is water depth, which is directly related to changing tides. This is why rip current risk may be reported as moderate at 1 p.m. and become high at 4 p.m.
The Ocean City Beach Patrol provides rip current assessments to NOAA three times each day. We have also worked directly with scientists to understand rip currents and how to better forecast and predict them.
Rip currents do not pull a person under water as a lot of people believe. It is the deep channel cut into the sandbar that gives the impression that a swimmer maybe pulled down.
In reality what is happening is a non-swimmer who intended to remain only in waste deep water is being moved by the rip current into increasingly deeper water channel. Since they cannot swim, they try to stand on the bottom and as they move away from the shore the water becomes over their head and they are no longer able to keep their head above water.
Therefore, a person watching from the beach may think that what they believe they are seeing is a person being pulled under. In fact, it is a non-swimmer who does not have the ability to keep their head above water.
If this occurs while the beach patrol is on duty, the lifeguard will simply assist the person back to safety. However, if this occurs while lifeguards are not on duty, the outcome could be deadly.
You may believe that only non-swimmers drown as a result of rip currents while in reality many rip current drowning victims had moderate to good swimming ability. This brings up the question, why would a person who knows how to swim, drown? The answer is simple.
Panic, fatigue and lack of ocean awareness all contribute to the outcome. A rip current is very much like a treadmill. As water is flowing away from the beach, a swimmer attempting to swim straight in will make little or no progress against this outgoing current.
Since a rip current may flow faster than an Olympic swimmer (Michael Phelps) can swim, swimming against this current only causes a person in this situation to become fatigued while getting no closer to the beach.
Eventually they become so fatigued that they are no longer able to keep their head above water and once they slip below the water’s surface and are no longer able to get air, they become unconscious and only have moments before they become a statistic.
In contrast, a swimmer or someone with a flotation device can easily escape the pull of the rip. By nature a typical rip current is not very wide usually 20 yards at most which means that a person who is being pulled out can be out of the rip after a few swimming strokes.
Also, once the rip current flows through the cut in the sandbar the pull disperses and the current no longer continues to pull you away from shore. With these facts in mind if you find yourself being pulled away from shore, do not panic, simply swim parallel to shore and once you no longer feel the pull of the rip, swim back into shore.
If you feel you are unable to swim across the rip relax, let it take you out to the sandbar and then swim back to shore. Whatever you do, never abandon a flotation device and always signal the lifeguard if you want their assistance.
In most cases they will already be on their way to assist you back to safety. Even our lifeguards will not attempt to swim straight in against a rip current. They use their knowledge of the ocean to swim parallel to the beach until they are out of the rip current and then make their way back into safety with a victim in tow.
If you can remember the word RIP then you can remember what to do to save your life, R = Relax and do not panic, I = I need help (wave your arm), P= Swim Parallel to return to safety.
For additional information about rip currents and other water safety topics visit our webpage, www.ococean.com/ocbp and follow the safety button.
NOAA also has a very informative site to learn more about how they occur and how to remain safe: http://www.ripcurrents.noaa.gov/ .
Last year we attended a Rip Current and Surf Zone conference at the University of Delaware. It was exciting to be able to network with other organizations including NOAA about rip current and surf zone research.
NOAA also presented the beach patrol with an award for “Rip Current Awareness and Prevention” at a meeting of the Mayor and City Council last season. We also had Scott Schumann, IT officer from NOAA, come and train our lifeguards this year as we continue our partnership for identifying, predicting and understanding rip-currents.
My best advice to you is to only swim when lifeguards are on duty and you can always approach any of our friendly and knowledgeable lifeguards and ask them to talk to you about current conditions and information about rip currents.
If you think you would like to make a difference and have an exciting fulfilling position with the beach patrol, ask any of our guards or visit our website at www.ococean.com/ocbp.