Friday, March 11, 2011

Ice Jams and your Ancestors

The news lately has all been weather and earth related. Frigid temperatures, tsunamis, earthquakes, mud slides, and here in New Hampshire and Maine we’ve had a spate of ice jams. The local TV news shows amazing film of ice crushing against bridges and dams, causing flooding and widespread damage. The rest of the country asks “Ice what?”

The 1936 Flood in Nashua, New Hampshire
was caused by ice jams and spring rains

An ice jam is caused by an accumulation of floating ice, usually in a river, that restricts the water flow and causes flooding upstream. When the ice jam releases, damage is caused downstream from the sudden flow of water and ice. Usually the crush of ice weakens or destroys bridges and dams.

The local Manchester, New Hampshire newspaper ran an article yesterday about the all the flooding since the unseasonal rains. For example, in Keene, the Contoocook River in Peterborough sent water flowing over Route 202.  Last year the Pemigewasset River was a foot over flood level due to ice jams. Closer to home the police were monitoring the streets of Pinardville, in Goffstown, which are prone to flooding.  Even the Charles River, west of Boston, is above flood stage this morning.  This much rain is unusual, causing the ice in the rivers to loosen and the snow pack to melt much faster than through regular thawing.

According to the US Army Corps of Engineers, the earliest ice jam disaster occurred in 1780. They keep an Ice Jam Database on over 12,200 ice jam events, each with a narrative description. The latest ice jam disaster occurred right here in New Hampshire, on 24 January 1999 in the town of Littleton. On that day 40 senior citizens were evacuated when the Ammonoosuc River and its ice and water flooded near their assisted living center.

Many people remember the 1936 Flood in New Hampshire, but few remember that it was caused by both ice dams and open flooding. Industry along the rivers lost $5,000,000 (1936 USD) during the depression, which not only was a huge amount of money for the time, but also many scarce jobs were lost. Total property damage exceeded $100,000,000 (1936 USD). About 150 to 200 people lost their lives. The Millyard Museum in Manchester has many photographs of the flood, and the aftermath. I particularly remember one photo of the water up to the second floor windows of one of the mill yard buildings. That is a lot of water!

If your ancestors or relatives tell stories of lives and property lost during flooding, you might be able to trace it to a flood caused by an ice dam. Using a combination of newspaper accounts and the Ice Jam Database, you can find exactly where the damage occurred, names of victims, estimates on property damage and narratives of the event. Ice jam flooding usually occurs between January and March.

I Googled “ice jams” “New Hampshire” and went to the Google news search. I started reading articles from the 1920’s. The first one was from the “Lewiston Daily Sun” in Maine, dated 13 February 1925. It described a stretch of warm weather and rain that was similar to the conditions here this week. According to the article “…so warm that some have even allowed their furnace fires to go out.” This was followed by descriptions of flooding in sections of Lewiston and serious damage due to ice jams. Boats were floating in the streets of Montpelier, Vermont and two people were injured when the cold water hit a boiler, causing an explosion. The front page articles also covered ice jam flooding stories in New Hampshire and Boston, Massachusetts.

I can imagine that in the future my descendants would be reading articles from the “Nashua Telegraph” and the “Manchester Union Leader” to see what the ice jam events were like in March 2011.


For more information:

The photo above is of Nashua, New Hampshire in the aftermath of the March 1936 flood from the NOAA Easter Regional Headquarters website  An article from the US Army Corps of Engineers which lists many references such as newspaper articles on disasters in the state of New Hampshire.

U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) (part of the U.S .Army Corps of Engineers) welcomes inquires about their database. Call 603-646-4361 or write to:
ATTN: J. C. Tatinclaux
71 Lyme Road
Hanover, NH 03755-1290

The Manchester Millyard Museum and the Research Center are run by the Manchester Historic Association   There is an online library catalog of the books and most of the photograph collection. There were over 212 records found relating to the word “Flood” and most were related to photographs and scrapbooks pertaining to the 1936 and 1896 floods.

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Copyright 2011, Heather Wilkinson Rojo


  1. This bowls me over, because I have never heard of an Ice Jam before. It sounds dangerous--water and freezing at the same time. Thoughts of the Titanic. No wonder Ice Jams can kill. NH has had so much power loss due to ice in the last few years, anyway (I have friends there).

  2. I was reading the Greenfield MA Annual Town Reports, which made note that WPA labor was used in the clean up for the 1938 flooding.

  3. I read in the Greenfield MA Annual Town Reports that WPA labor was allowed to be used in the cleanup of the 1938 flooding.