Common Problems in the Construction of Eruvin in Urban Areas part 2

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    Several years ago, during a routine tour of an eruv located in a coastal community, it was discovered that a large saltwater inlet was encompassed by the eruv. This inlet had previously gone unnoticed because it was surrounded by a thicket of reeds. Examination of other thickets in the area revealed that some of them were in reality marshes. These proved impassable, even by local youth equipped with machetes for the specific purpose of trying to traverse these thickets! The problem that had arisen was the obscure halacha of "karpaf."

    We have already mentioned the problem of walls that are einam mukafim l'dira. An area may also be considered "eino mukaf l'dira" if it is not an area designated for human habitation. Such an area is called a karpaf. If a karpaf that is larger than five thousand square amos (a "beis se'asayim") is included within an eruv it renders the entire eruv invalid37. The Poskim extend the definition of human habitation to include any use of the area in question for human needs. This would include parks and any other area suitable for walking or strolling, but not planted fields, unless there are walking paths between the furrows. The Rashba, quoted in the Shulchan Aruch38, states that if a body of water included within an eruv is suitable for human consumption, and possibly even if it is suitable for laundry, then, even if it is more than five thousand square amos, it does not invalidate the eruv. This excludes salty or brackish water. The Dvar Shmuel39 does allow a karpaf within an eruv consisting of real walls, but this is generally not relevant in modern urban settings. The Divrei Malkiel40 rules that if an eruv was built around an area that contained a pre-existing karpaf, then the hekef l'dira of the eruv enclosure counteracts the eino mukaf l'dira of the karpaf. Such an eruv is therefore valid. The case in question in that teshuva, however, concerned an area that was technically suitable for walking, only the gentile owner would not allow anyone to actually do so. The Divrei Malkiel employs several reasons in validating the eruv that included this karpaf. It is therefore difficult to isolate one of his reasons and extrapolate l'heter solely from that one reason to other cases41. The best solution is to exclude a questionable area from the eruv (this may be achieved by constructing a tzuras hapesach around the karpaf itself).


    We will not deal with the construction of eruvin in true reshuyos harabbim in this kuntres. We should, however, note briefly that a street that is a reshus harabbim must be rectified by means of doors, which are regarded as true walls (see also Part 2 Section 1 below). Many modern eruvin employ some innovative form of delasos, such as tarpaulins wrapped around light poles that, at least theoretically, may be drawn across a street and close it off42. The halachos of delasos, however, are just as controversial as the halachos of karpaf. Excepting Amsterdam (where the authorities would not allow use of standard tzuros hapesach), delasos are usually used only as a snif (an additional heter) - adding weight to other heterim already employed43.


    It is customary to check a municipal eruv every Erev Shabbos. What happens if subsequently, on Shabbos, it is discovered that the eruv is in fact pasul? The Poskim rule that one should not attempt to notify the population of this development. The reason they cite for this ruling is the principle of mutav sheyeeheyu shoggegin v'al yeeheyu mezidin - since many people will be skeptical of a declaration that an eruv is pasul and will carry anyway, better that they remain unaware of their sin than that they be made aware of the possible problem and sin intentionally44. I have heard from my great-uncle that Rabbi Chaim Soloveichik in Brisk ruled similarly, but for a different reason. Reb Chaim's rationale was that people who carry under the mistaken impression that the eruv is valid fall into the Halachic category of Mis'asek. A Mis'asek is one who commits any forbidden act thinking that it is permissible. When it comes to Hilchos Shabbos, where only Meleches Machasheves, intentional activity, is prohibited, a Mis'asek's deeds are not considered sinful at all, and do not require Teshuva45. Since the people that are carrying do so because they think that the eruv is still valid, they are committing no wrong.

    This leads us to an interesting question. If a city's eruv is pasul, why bother fixing it or informing others that it is invalid? As long as the Rav HaMachshir and whoever else knows that the eruv is invalid do not carry, everyone else should be considered Mis'asek, and thus are not liable for carrying! The Poskim discuss the related issue of a new Rav taking over the supervision of an eruv built by his predecessor that is clearly invalid. Must the new Rav immediately pronounce the eruv invalid46? Clearly, very basic issues of public Emes and Sheker are involved in such circumstances. In each subjective situation a Posek must be consulted. It is worth noting that the Maharshal47 states that willful falsification and distortion of Torah precepts is a capital offense.


    A word of caution: Due to the complex nature of these halachos, it is imperative to consider the specific nature of the terrain, equipment, and appearances of any situation that may generate she'eilos. It is therefor crucial and essential that a Rav be taken to personally inspect the scene out in the field48. Facts related to the Rav may not accurately portray the circumstances of the case, leading to an inaccurate psak49.

Converted by Andrew Scriven

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