News / 7.2.2019

Ilmala’s snow-melting field operating on district heat in use for the first time

Preparations for snow-rich winters were started at the Ilmala railway yard already two years ago by building a snow-melting field, which operates on district heat. This winter, the snow-melting field has been a great help in keeping the trains running smoothly.

In snowy winters, the railway section between the Helsinki central railway station and Pasila is challenging in terms of melting the snow. The problem has been solved with a snow-melting field built in Ilmala, where snow is melted with district heat.  

“We wanted to develop an eco-friendly and efficient way to handle snow in a dense urban environment. Since the snow cleared from the railway network is relatively clean, it is better to melt the snow and discharge the resulting water into the sewer rather than transport it by lorry out of town,” says Regional Manager Eero Liehu (Maintenance Area for Southern Finland, Finnish Transport Infrastructure Agency).

Sufficient heating of the properties in the railway yard has also been optimised in the solution: district heat is used for melting snow only when the temperature remains above -10 degrees Celsius. When the temperature falls below -10, the full capacity of district heating will be used on the buildings.  

“The solution for the railway section crucial for rail transport clearly demonstrates the intelligence of the district heating network in Helsinki: all available heat of the district heating water is utilised. The district heat return water, which has already been used for heating the properties, will still have plenty of energy left for melting the snow,” says Helen’s Account Manager Reijo Lemetyinen.

Melting of snow in the railway section is also cost-effective: the costs are only one-tenth of the cost of transporting the snow away by lorry.  

In addition to heating of properties, district heat can be used for keeping streets clear of ice and for melting snow.


  • The 2,500 m2 snow-melting field located between railway tracks can be used for melting up to 100,000 m3 of snow with district heat, as necessary, during a single winter season.
  • After the start of areal development, snow masses can no longer be transported to Central Pasila. 
  • However, when necessary, snow can still be transported to the 100,000 m3 disposal site in Ilmala, although in snow-rich winters this will not be sufficient.
  • The snow-melting system was designed for the Finnish Transport Infrastructure Agency by Ramboll Oy.   

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