(Aug. 15, 2014) People were amazed and entertained last week by the formation of several very large tide pools along the 10 miles of Ocean City’s beach.
This typically happens this time of the year. We commonly refer to these as tide pools. However, they are not only formed by the outgoing tide but are also formed when large waves are driven further onto the beach by wind or during storms. Tropical activity in the Atlantic during this time of the year can cause larger than usual waves and surf conditions. When this happens, these waves bring more water onto the beach and if it becomes trapped in a low area a “tide pool” may form.
These low areas on the beach are formed as waves push sand into large mounds running parallel to the shore with the area behind the mound (to the west) being lower than this newly formed retaining mound. As water is pushed over this mound, it cannot make its way back into the ocean as runoff and becomes trapped in the low lying area.
Although the amount of water, the size of the low lying area and the depth of low lying area, may vary from a few inches to a few feet deep and the size may be as small as a backyard pool or as large as several city blocks, most tide pools are only a few inches deep and less than a block long. Because of the relatively small quantity of water, the sun heats it and it is much warmer than the ocean and it usually has no wave action making it very inviting.
When a child comes to the beach and finds a tide pool, they become very excited. It is like having a backyard pool on the beach. However, tide pools pose their own dangers. Because a tide pool seems like the perfect place for small children to play, parents often do not give the same attention to their children as they would if they were playing in the ocean. Further complicating this is the fact that most often the tide pool ends up forming behind the guard stands. This means that the Surf Rescue Technician is only scanning this area as part of their secondary scan giving much less attention to this water hazard than the large body of water directly in front of them.
Parents often have a false sense of security due to the shallow depth of most of these tide pools but those of us in water safety realize it only takes 1 inch of water to drown a toddler. A second hazard associated with this phenomenon is the risk of injuries from running and jumping into such a shallow area. Although not a safety concern another potential issue has to do with this trapped water becoming stagnant, dirty, and smelly. Therefore, the Public Works Maintenance Department sculpts the beach to facilitate the drainage of these tide pools after they have remained for a couple of days.
Sometimes you might find a tide pool that behaves more like a water slide than a pool. This was the case last week in Ocean City. In this instance, wave action was bringing more water into the low area while breaks in the retaining mound allow water to flow back into the ocean resulting in strong currents being formed in the tide pool. When this happens, the tide pool becomes far more dangerous as people playing in the tide pool might find themselves washed into the ocean. This action is the perfect model of what is happening out in the ocean as waves come across the underwater sand bar and then make there way back out to the deeper water which is the mechanics and cause of the deadly rip currents you have heard so much about.
Although we have given some cautions about tide pools, they can be fun when enjoyed safely. This season the tide pools have already formed in several locations. Hopefully, you will be lucky enough to see one and pass along our cautions to the people you are with. One of the tide pools that formed last week, did find a break in the crest of the beach (retaining mound) and created one of the fast flowing “water slides” we referred to on our OCBP Facebook page. A witness to this phenomenon filmed it and posted it on YouTube. You can view it on our Facebook page.