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The Association of State Dam Safety Officials (ASDSO) supports the proclamation of April to be Low Head Dam Public Safety Awareness Month.

According to the American Society of Civil Engineers (ASCE), "A low head dam is a manufactured structure, built in a river or stream channel, extending fully across the banks. A low head dam is designed and built such that water flows continuously over the crest from bank to bank. If water levels rise downstream, a submerged hydraulic jump can form which produces an upstream directed current that traps any recreationist who might go over the dam."

To see the locations of known low head dams in Indiana, visit this page from the Indiana Department of Natural Resources. For safety information on low head dams, visit this page, also from IDNR.

Low head dams are often colloquially known as "drowning machines" (link courtesy Iowa DNR) due to the hazard they pose to swimmers, kayakers, and other recreationalists, who may not recognize the structures or be aware of the turbulent currents they can cause, which are extremely difficult to escape.

Stay out of the Drowning Zone. Source: Iowa Department of Natural Resources

ASCE is encouraging the public to assist in identifying low head dams across the country to create the National Inventory of Low Head Dams, a database of low head dams for the protection of the public. 

Click here to see a short documentary on the hazards of low head dams in Indiana and elsewhere from local public television station WFYI - "Over, Under, Gone: The Killer in our Rivers."

For even more on low head dam safety, see this link from our partners at the ASDSO.

Can you spot the potentially deadly low head dam in the first of the following two photos?


Upstream side of a Low Head Dam


Downstream of a Low Head Dam
Downstream side of a Low Head Dam


Click the image to enlarge graphic. Source: Indiana Department of Homeland Security

As part of our mission to build a Weather Ready Nation, NWS Indianapolis is a proud participant in the Indiana Silver Jackets, an interagency partnership for natural hazard mitigation and solutions sponsored by the U.S. Army Corps of Engineers.  NWS Indianapolis reminds you to respect the power of water at all times, and Turn Around, Don't Drown!