Bridges are dangerous in cold climates; because they cool more quickly than regular roads, ice can form when the rest of the road seems safe. More de-icing chemicals are used, which can cause the bridge to deteriorate.
In Fukui, Japan, the Snow Management and Construction Technology Research Center has developed a system where they store summer heat for snow-melting in winter by driving a large number of dedicated heat-exchanger piles into the riverbank.
According to Japan for Sustainability:
This is a closed-conduit system, in which heat-radiating pipes built in the bridge surface and 378 piles (42 rows and 9 columns) embedded 1.5 meters apart into the riverbank are connected through a circulation pump. During daytime in summer, the circulation pump operates automatically as the bridge surface becomes hot, carrying the heat to the underground storage piles. This system warms to 35 degrees Celsius a section of the riverbank measuring 15 meters wide, 64.5 meters long and 23 meters, and maintains the temperature until December for snow melting.
Counting emissions from construction and 50 years of operation, this new technology will result in one-twenty-fifth the carbon dioxide emissions compared to conventional electric snow-melting equipment. ::Japan for Sustainability and ::Snow Management and Construction Technology Research Center