Stay Clear, Stay Safe

Hydroelectric Dams and Stations are NOT Safe Places for Recreation

There are dangers in coming too close to hydroelectric dams and stations. A spot that looks calm and safe one moment can become dangerous within a few seconds as water levels and flows change, often without warning. Calm waters or a dry riverbed could change quickly into one with rapidly moving, dangerous waters.

DANGER Dam Outflow, Keep Out

Most hydroelectric dams and stations are remotely controlled by operators stationed many kilometers away. Throughout the day and night, as demand for electricity rises and falls operators open and close dams, and start and stop generating units. This results in frequent and rapid changes in water levels and flows around dams and generating stations, changes that can affect the safety of those who venture too close.

Waters in the headponds above hydroelectric dams and stations and the waters below them are particularly dangerous. At a generation station, water from the headpond rushes into the station, turning large turbines that produce electricity. The water rushes out of the station, to join the main stream of the river. At dams excess water can be released through gates into formerly calm or dry riverbeds below. At both dams and stations, the fast-moving water creates dangerous turbulence and strong undercurrents.

Even if you can't see a generating station or dam, waterways upstream and downstream can still be affected by their operations. It's important to be aware of the potential dangers caused by changing water flows, and to stay clear of the waters near stations and dams.

Hydroelectric dams and stations, and the areas around them are:

  • NOT parks
  • NOT fishing holes
  • NOT boating areas
  • NOT swimming areas
  • NOT camping sites or picnic areas
  • NOT snowmobile or X-Country Ski areas
  • NOT safe places for recreation

Obey all warning signs. Symbols show the consequences of not staying clear.

EXTREME DANGER - Dam Upstream - Keep Out - This Reiverbed Floods Without Warning

For your own safety near a hydroelectric dam or station, make sure that you:

  • Obey all warning signs, fences, buoys, booms and barriers. They are put there to protect you. The areas inside are dangerous, stay clear of them.
  • Stay a safe distance outside of warning signs, buoys, booms and barriers when fishing, boating or swimming.
  • Stay well back from the edge of waters above and below hydroelectric dams and stations
  • Never stand below a dam, or anchor or tie your boat there. Rapidly changing water levels and flows can take you by surprise and could swamp your boat or put you in the grip of an undertow.
  • Stay off hydroelectric dams or station structures, unless OPG has clearly indicated walkways, or observation points.
  • Stay well back of dry riverbeds below dams. They can quickly change into rapidly flowing waterways.
  • Stay well back from the edge of a waterway where footing may be slippery.
  • Don’t wade into moving water.
  • When swimming, fishing, boating or paddling in a river, be aware of the water level and check upstream frequently for any sign of increasing currents or rising water levels. If the water level is rising or the flow is speeding up, get out of the water or move your boat downstream. Even when the hydroelectric dam or station is out of sight, changing water levels and flows can take you by surprise, pulling you into an undertow, leaving you stranded away from shore or swamping your boat.
  • Set an example for children, who may not be aware of the dangers, even if they can read. State explicitly where they can and cannot go and make sure you are close to them and can see them at all times.

Winter poses additional dangers

Hydroelectric dams and stations operate all year round, 24 hours a day. Their operation affects water flows and ice conditions. Ice that forms near a hydroelectric dam or station can be thinner and more inconsistent than in other locations because of the changing water flows beneath it.

  • Avoid snowmobiling, cross-country skiing, skating or ice fishing on rivers or lakes near dams and generating stations.
  • Don’t risk walking onto a river or lake where the ice may be thin due to the current or where changing water levels have pushed water on top of the ice.

We take pride in operating our facilities safely and in a manner that respects the environment and the rights of other users of the waterways. Your safety is important to us. Please respect the hazards near our dams and stations, and heed warning signs, booms buoys and barriers. They are there for your protection.

For more information about safety around hydroelectric dams and stations, to obtain a free video, or freeinteractive CD-ROM for children, visit

Ontario Power Generation

Remotely Operated Dam Gates

When opened, remotely operated dam gates can quickly turn a calm or dry riverbed into one with dangerous flows.

Remotely Operated Dam Gates

The same spot just minutes later. Remotely operated dam gates release large volumes of water that could swamp your boat or put you in the grip of an undertow


These anglers are in a dangerous spot and should not be there. Areas inside warning signs, buoys and booms are dangerous, stay clear of them

Obey All Warnings

The area between booms and dams is very dangerous. Stay clear–obey all warning booms, buoys, signs and barriers.

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