Gritting material for winter road clearance: Is salt or brine better?

When snow and ice dominate the roads, many farmers and contractors use their machines to help with winter road maintenance. In addition to clearing snow-covered roads with a snow blade, gritting is also a common task. For a long time, salt was predominantly used for gritting - however, the trend is now increasingly moving away from the use of dry salt and towards other alternatives. Brine in particular has become increasingly popular as a gritting agent in recent years. But what are the advantages of brine compared to dry salt? And what should you as a farmer bear in mind when using it?

Dry salt: the classic against ice and snow

Gritting salt, de-icing salt or road salt are just some of the terms by which dry salt is known. These terms generally refer to salt that consists largely of sodium chloride and is used as a de-icing agent in winter road maintenance. The advantages of classic dry salt are obvious: it is easy to store and can be spread using classic spreaders for dry gritting material. In addition, salt is still considered a particularly effective de-icing agent for large amounts of snow. Unfortunately, however, dry salt is repeatedly criticized for various reasons. The highly concentrated salt dissolves in water and is then absorbed by plants and trees at the roadside, which in the worst case can lead to the death of the plants. In addition, the dry salt not only damages the machines in the long term, but can even dissolve concrete. Problems are also encountered when spreading dry salt: In strong winds or at high driving speeds, the salt often does not remain on the road, but is carried to the edge of the road in a very short time. Here, of course, it does not have the desired effect.

Pre-wetted salt: the middle way between salt and brine

One gritting agent in particular is becoming increasingly popular with local authorities: pre-wetted salt, also known as F30. Pre-wetted salt consists of 70% conventional dry salt and 30% brine. When spreading, the dry salt is moistened with the brine. The big advantage: the wet salt adheres directly to the road surface, minimizing losses to the side. Disadvantage of this method: Instead of a simple spreader, a combination device is required which additionally moistens the salt during spreading.

Brine: Gritting agent of the future?

Brine, also known as F100 in specialist circles, is becoming increasingly popular in winter road maintenance. The liquid, which consists of 22% salt dissolved in water, has several positive properties. On the one hand, significantly less salt needs to be used to achieve a comparable effect to dry salt. The Zweckverband Abfallwirtschaft Region Hannover (aha) tested the effectiveness of brine spraying on cycle paths for three winter maintenance periods. The result: with brine, 30 ml per square meter was needed, which corresponds to around 6.6 g of salt. With dry salt, more than three times the amount of salt would have been needed to achieve the same result. This salt saving is not only good for the environment, but also for your wallet. In addition, brine can be applied very precisely and works quickly and reliably even in dry, cold conditions. Brine can also be used as a preventative gritting agent down to temperatures of -10°C. However, brine is only of limited use as a gritting agent for large amounts of snow or very low temperatures.