Inshore Holes

An inshore hole is a trench in the sand that runs parallel to the shoreline anywhere from one foot, to fifty feet from shore. It can vary in depth and width depending on the size and direction of the surf and the long-shore current. They range from only a couple of feet wide and small enough to step over, to twenty feet wide and deep enough to fully submerge a full grown man standing on his toes. Inshore holes are common at long stretches of sandy beach where the long-shore current can run freely for a long period of time and distance. Because inshore holes are generally close to shore, they present a significant hazard to young children and unskilled swimmers who expect it to be shallow. Inshore holes can exist in some shore-break conditions and are commonly filled with pebbles, shells, and other sharp debris. These kinds of inshore holes can be especially treacherous as they cause waves to break onto dry beach without any water to cushion a person being knocked down by the wave.

Sandbars

A sandbar is a ridge of sand formed in a river or along a shore by the action of waves or currents. Sandbars are common at beaches with inshore holes and are basically underwater sand dunes that have been built by waves and currents pushing the sand into mounds as opposed to the winds of the desert. Sand bars can be completely submerged, or become exposed during low tides. They can be small and isolated, or large and reoccurring in areas of steady current flow such as river mouths. In any case, they cause waves to break abruptly and with unusual force in shallow water. Surfers and swimmers can seriously injure their necks when diving head first either off their surfboards, or while attempting to dive under the waves. Sandbars can shift around and appear and disappear on a daily basis. It is important to always enter the water feet first and to keep your hands in front of your head at all times to avoid being surprised by a head-on collision with on of these hidden hazards. (see Images 1 and 2)

Image 1: Arial view of a sandbar. Waves. currents, sand grain sizes, sandbar configurations, water table levels beneath the beach, and other phenomena combine in complex ways, causing very different patterns along the same beach. Photo by Steve Elgar .

Image 2: Boat breached on a sandbar.

The waves at Zuma beach in Malibu break on a sand bard that runs nearly the entire length of the beach. Inshore holes can be found to the inside of the sandbar at Zuma beach but are always changing sizes and locations.

Whenever you enter the water in is important to cautiously inspect the oceans’ bottom. Inshore holes are a leading cause in broken and or twisted ankles at beaches with sand bottoms. Beach goers will run into the water not realizing there are many holes in the ocean floor that which can cause serious foot, ankle, or leg injury.

Sources:
The American Heritage Dictionary of the English Language, Fourth Edition. Copyright © 2000 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
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