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Living with Dams: Know Your Risk | April 2012
Aside from the possibility of
failure, dams also pose risks to
swimmers, fishermen and boaters.
Small dams, also known as low-head dams, “killer dams” or “drowning
machines,” are deceptively dangerous. These dams are especially
dangerous to swimmers and boaters since they are often hard to see,
especially from the upstream side. Boaters who go over a low-head
dam are often trapped in a submerged hydraulic jump or “roller”
formed just below the dam. Likewise, swimmers and fishermen who
get too close to dams can be caught in this dangerous circulating
current.
Hundreds of people have been killed at low-head dams, but few states
regulate these dangerous structures.
**STAY SAFE AROUND DAMS
Summer
Always stay outside booms and away from all dam structures.
Never swim above a dam or dive from a dam structure. Currents
can pull you through the dam or pull you against flow structures
with such force that you could not escape.
Never fish, boat, or swim below a dam. Water levels and flows can
change very quickly and you may not be able to react in time to
avoid the danger.
Personal water craft and boats should always stay clear from dams.
Never moor, tie or anchor your boat below a dam.
Never sunbathe, picnic or camp in an area which may become
flooded due to dam operations.
Autumn
All-Terrain Vehicles (ATVs) should be used with caution around
water. Operators should be aware of possible changes in water
flows or levels from dam operations.
Always obey posted signs, and do not enter fenced areas to hike,
or access hunting or nature viewing areas.
Winter
Beware of thin ice that may develop due to dam operations.
Never venture out on the ice alone. Always wear a life jacket and
carry a throw rope.
Dam operations often result in lowering of water levels
throughout the winter and spring. However, this can result in ice
collapsing onto lower water levels and then water seeping up
under the snow. When venturing out on the ice, always be aware
of the potential of slush under the snow over ice. Travel in slush
conditions is very difficult regardless of the mode of travel.
Spring
Stay clear of dams when fishing. Water flows and levels can
change quickly.
Canoers and kayakers should always stay clear of dams.
General
Stay off the dam structures unless the area is clearly marked for
public travel.
Be alert to changes in water levels.
**Ontario Ministry of Natural Resources website - 2012