Can I shovel snow on Shabbos

Question:

Can I shovel snow on Shabbos? Can I spread salt on my walkway on Shabbos?

Note: we are assuming that the snow is in a place where people may slip on it.

Discussion:

If the snow is still soft (i.e. it is fresh and has not frozen over) one would be permitted to clear a path. However, if the snow has hardened it may be prohibited because it is a form of Boneh (building). Some poskim do not make this distinction between soft snow and hard snow (Orchos Shabbos vol. 2 pg. 94). If the snow is on a dirt path one should not shovel it because he will certainly come to being Mashveh Gumos – leveling the ground (Sefer 39 Melachos pg. 1098). Some poskim are of the opinion that one may not shovel  snow under any circumstances because it is Tircha – strain (Lev Avraham siman 49).

Normally, it is prohibited to add a layer of material to the ground as this is a form of Boneh. However, one is permitted to spread salt over an icy patch because the salt will dissolve and is therefore only temporary. Never-the-less this would still be prohibited under rabbinic law, but in this case where the purpose is to prevent harm it is permitted. One would even be permitted to spread a salt substitute over the ice patch even though those items are normally muktzah (Rema 308:6).

Spreading sand is somewhat more questionable because it is more permanent then salt. Some poskim permit it based on the idea that even the sand is not permanent because the rain will wash it away or it will get swept away when the weather gets warmer (Shmeras Shabbos Khilchasa 25:9). However, this would only be true if the sand was spread on a concrete walkway.

According to some poskim breaking up ice with a shovel would be prohibited because of Sterrah (destroying). However, if there is a danger that people may slip and hurt themselves it may be permitted even according to these poskim, one should consult with his rav. Everyone would agree that spreading salt is permitted.

Summary:

Some poskim say that one can shovel snow on Shabbos if it is in a place that people may slip on it. Other poskim are of the opinion that soft snow may be shoveled but snow that has hardened may not be cleared away. A third opinion is that one may not shovel snow in any circumstance. One should ask his rav what to do.

One is permitted to spread salt or a salt substitute on a patch of ice on Shabbos. Breaking up ice with a shovel is more problematic, but if it is in a place that may cause someone to slip it may be permitted. In this situation a rav should be consulted. Spreading sand is also more problematic then salt, again, a rav should be consulted.