Giant Snow Mounds

Posted by Richard Primack

“For many years I was the self-appointed inspector of snow-storms and rain-storms.”  

- Thoreau in Walden. 

Giant snow mounds still towering in our parking lots in late April remind us of the three powerful northeaster snowstorms that made this past March one of the snowiest on record. Government departments and large landowners are no longer allowed to dump excess snow into rivers, the ocean, or other bodies of water because of salt, trash, and possible toxic materials that might be intermixed with the snow. So they create mountains of snow that melt in the spring.

The parkway snow mound was dirty white in late March

This year’s snow mound on the Hammond Pond Parkway in Newton was enormous; a 300 foot long, 48 foot wide, and 21 foot high wall of snow. Making some simple assumptions, this mound was about 5000 cubic yards in volume, or 400 dump truck loads of snow.

In late March the parkway mound was dirty white, but it has now become blackish, as the snow melted, leaving behind sand, soil, and other debris on the convoluted and eroded surface. Much of the surface dirt is jagged, rice grain-sized fragments of black rubber; this is probably “crumb rubber” used to provide cushioning on athletic fields. The surface of the mound also has scattered grass clumps, large rocks, logs, sticks, chunks of concrete, and metal and plastic junk.

As the snow melted, the surface became convoluted and increasingly black

Three weeks ago, the air temperature was a pleasant 55 degrees, and the nearby forest floor was 62 degrees where it was warmed by the sun. In contrast, the snow mound surface was a chilly 36 degrees and a frigid 28 degrees 6 inches below the surface. Water dripped from the sides and small springs of icy cold water emerged from the base of the mound. Most of the water leaving the mounds was probably evaporating and sublimating directly from snow to airborne water vapor.

Much of the debris on the surface was black crumb rubber from athletic fields

It is a fun game to guess when the giant snow mounds might finally melt in the spring. We will probably have many more opportunities to observe the melting of such snow mounds—because of climate change, winter storms are predicted to become more frequent for our region.

This posting is a summary of longer article published in the Newton Tab.