Last Updated on July 13, 2022 by Ecorf
Water bodies are known to be a great location for recreational and competitive activities. Fishing, scuba diving, and canoeing are just some of the vast thrilling activities that we engage in daily.
Sadly, it is not always fun and games as accidents are likely to occur.
Drowning is one of the main hazards of water activities. Events causing these drownings range from unstable weather conditions to physical events like “low head dams” and human carelessness.
What Are Low Head Dams
Often referred to as “drowning machines” due to incorporated submerged hydraulic jump, Low head dams consist of a barrier across the width of a river, which effectively alters the normal flow of water. This leads to a free flow of water over the top of the barrier before falling down to a lower level.
The distance between two levels ranges from 6 inches to astonishing 25 feet, and although they are still useful for some genuine purposes, the popular belief is that they have outlived their usefulness.
In the last few years, quite a number of people have lost their lives to low head dams. The high rate of deaths caused by low head dams makes it something everyone should make sure to pay a lot of attention to.
What Makes Them Dangerous
There are a vast number of events that makes these dams a really dangerous part of recreational and competitive aquatic activities:
They Are Virtually Impossible to Spot
A major use of low head dams is in competitive aquatic activities like kayaking or canoeing. Due to the low structure of a kayak or canoe and the barrier of the low head dam being fully submerged, it is really difficult to spot the area that indicates them. This effectively reduces reaction time.
The Pressure Generated
The pressure in these dams is really great, such that they can pin anything or anyone underwater. Being a good or professional swimmer doesn’t really help much as the pressure also sucks in debriefs like wood which effectively creates a much more difficult environment to swim out off.
No Assured Rescue Operation
Kayaks and canoes are not the only watercrafts that can be wreaked by the low head dam, as they’ve been known to capsize even rescue boats. The thought that a rescue team could be in the same predicament as the victim is quite startling. Floatation devices are also no good against the massive pressure of the “boil”.
The Dreaded “Boil”
The incorporated submerged barriers effectively cause a change in the level of flow, quickly turning the river into “mini-waterfall”. This means the water flowing from the top-level would apply a lot of current when it falls to the lower level. This current is referred to as “the boil”.
The current of the boil is so great that it sucks kayaks and boats alike underwater and pins them there. A kayaker in a boil would find it almost impossible to swim or paddle away while also pinned underwater.
They Are Not Marked
Most low head dams are not marked or located on maps and guides. Also, states don’t possess an inventory of how many of such dams are present in specific counties or states. These unmarked low head dams do not have warning signs which leads to kayakers unintentionally paddling into them.
Why Are Low Head Dams Made?
You must be thinking; “if they are this dangerous, why do they still exist”. It should be noted that not all low head dams are meant for recreational or sporting activities. The original reason for invention of these dams was never for recreational purposes.
A high number of low head dams were created in the 1800s, meant to power small industries. Mill ponds also used these dams efficiently as the energy created by the flow of water from the top level to bottom level was sufficient to power watermill, sawmills and some other equipment.
In modern applications, the low head dams are used to regulate flow rate. Increasing or decreasing the height of the barrier could effectively increase or reduce the volume of water flowing downstream.
This comes in handy during occurrences of constant heavy rainfall, resulting in flooding.
These dams are also used to alter the currents of larger water bodies, thereby making them initially inaccessible waterways accessible to vessels. Irrigation purposes and water supply are also some good uses of the low head dams.
This being said, it’s important to know that low head dam could be anywhere and you could unintentionally come up against one.
What To Do When Approaching A Low Head Dam In A Kayak Or Canoe
Avoid Them Completely
Low head dams are no joke and chances should not be taken regarding them. Some maps highlight the presence and location of these dams. If you see any warning or maps suggesting the presence of these dams, then the safest choice is to completely avoid it, don’t be reckless with safety.
Paddle To Shore
At this point, we’ve established just how dangerous these dams can be. Regardless of the fun and thrill we crave; safety should always come first which makes it wise to carefully paddle back to shore when you spot or suspect you are approaching a low head dam.
Go Round the Dam
For those hard-shelled explorers out there that would still like to proceed, you could go around the dam when you get to shore. This solution might require moving a reasonable distance to bypass the dam, which could be really stressful, but you know what they say about ‘will’.
To wrap it all up
The best bet against a low head dam is avoiding it completely. Make quality research on where you are about to explore and if it helps, follow a waterway that is familiar and normally accessible by other kayakers. Being alone in situations like this is the last thing you need, trust me. It is important you know the environment to avoid being caught unawares. Safety first, cheers.