Common Problems in the Construction of Eruvin in Urban Areas part 3

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1. Eruvin ibid., Shulchan Aruch, Orach Chaim 362:11. There are Acharonim who rule that b'she'as hadechak it is possible to rely with overhead cables on tzuras hapesach min hatzad. The overwhelming majority of Poskim, however, strongly disagree. See Rabbi Elimelech Lange's Hilchos Eruvin (Tel Aviv, 1972) 4:5-8, footnotes 67-68, and Rabbi Ovadia Yosef's haskama to the sefer. It is, furthermore, difficult to conceive of a true she'as hadechak in our circumstances. In 19th century Europe an eruv was often essential to bring water to one's house on Shabbos! In a teshuva written to Detroit in 1979, Rabbi Moshe Feinstein discusses what is considered a "tzorech" and/or "tzorech gadol" that would indicate that an eruv should be built in a community. See The Detroit Eruv (Oak Park, MI, 1986), p. 19. "Tzorech gadol" is not, however, license to build and rely upon a "she'as hadechak eruv." See also below footnote 22.

2. Frequently the overhead cable will run through a hole drilled into a wooden utility pole (known as a "bolt-through" pole). The use of such poles and cables as part of a tzuras hapesach hinges on a disagreement between the Mishna Berura 362:64 (l'chumra) and the Aruch HaShulchan 362:32 and Chazon Ish, Hilchos Eruvin 71:9 (l'kulla) about whether the lechi may extend above the cable or not. See also Nesivos Shabbos 19:31 and footnote 70; and Hilchos Eruvin 4:3 and footnote 62 (the latter source rules l'kulla in this scenario).

3. See Mishna Berura, ibid., no. 62. The Pri Megadim 363:19 states that there may not be a gap of twenty amos between the top of the barrel or other object used as a lechi and the overhead cable.

4. It may be possible to use a stripe consisting of several coats of thick paint as a lechi. The advantage of such a lechi is that it is more resistant to vandalism. The validity of this solution involves the halacha in Shulchan Aruch, Orach Chaim 362:11 that the tzuras hapesach must be strong enough to support a door made of straw. Painted stripes only possess such strength together with the surface upon which they are painted. The Mishna Berura, ibid., 363:26 allows such lechayayim if they possess some substance. See also Nesivos Shabbos, 19:24.

5. Orach Chaim, Eruvin 71:6. See Hilchos Eruvin 4:13 and footnote 82. The Aruch HaShulchan 363:46 also states explicitly that the cable must be directly "absolutely straight" over the lechayayim.

6. The lefthand diagram in fig. 3 shows a cable drawn across the top of the middle of a lechi. The Chazon Ish, ibid., rules that gud asek begins only at the top, not the middle of a pole. The Avnei Nezer, Orach Chaim 291:12 proposes a novel approach to such a case, which the later Poskim question. See Hilchos Eruvin 4:13 footnote 82 and Nesivos Shabbos 19:39, footnote 86.

7. In the first edition I noted here a remark of one of my Rabbeim that, like most halachos in Torah, decisions here must be rendered based on the perspective of the naked eye - both l'kulla and l'chumra (see Michtav Me'Eliyahu vol. 4 pp. 355-356, footnote 4). Rabbi Shlomo Miller, however, in his haskama to this kuntres, and others, took issue with the application of this sevara to inyanei eruvin. I therefore consulted that Rebbe, and he informed me that his original remark was not meant l'halacha, and directed me to remove it from the text.

8. Mishna Berura, Orach Chaim 363:112 on the basis of the Taz there no. 19. The scenario discussed there concerns a roof positioned between the lechi and the overhead cable, but it seems that the same halacha applies to this case. I am indebted to Rabbi Chaim Moshe Levy who foundthis ruling explicit in the Divrei Yechezkel no. 6 and cited a similar psak in the Avnei Nezer, Orach Chaim no. 231. See also Rabbi Shimon Eider's Halachos of the Eruv (1968) Chap. VII, I; and Nesivos Shabbos 19:27 and footnote 62. Sometimes, however, a problem of pischei shima'ei may be involved. See below, Section 3.

9. Chazon Ish and Hilchos Eruvin, ibid. The lechi itself, however, must be reasonably straight, not pronouncedly crooked or bent (any angle of more than approximately 25 degrees is problematic) (fig. 4). Otherwise, she'eilos of pischei shima'ei and other problems may be involved. See below, end of section 3; Chazon Ish, ibid. 71:11; and Hilchos Eruvin 3:13 and footnotes 83-84. See Halachos of the Eruv Chap. VII, C; Hilchos Eruvin 3:10; and Nesivos Shabbos, ibid., for discussions of overhead cables on an angle (i.e., where one supporting lechi is higher than the other). Rabbi Eider cites a psak from Rabbi Aharon Kotler that an angle of more than 45 degrees upwards or downwards is problematic.

10. Orach Chaim 362:66; see Nesivos Shabbos 19:42. See also Rabbi Tzvi Pesach Frank's Har Tzvi, Orach Chaim vol. 2, no. 18:8 and no. 19 for a significant kulla in this halacha.

11. Aruch HaShulchan, Orach Chaim 362:37. See also Hilchos Eruvin 4:2 and footnote 58. We must note, however, that the Chazon Ish, Orach Chaim, Eruvin 71:10 holds that at the moment when an overhead cable that is not taut blows in the wind beyond the width of the lechayayim the eruv is pasul! The Chazon Ish, ibid., 111:5 also holds that the overhead "lintel" of a tzuras hapesach may not be wider than the width of the lechayayim that support it. The rationale behind his psak is his opinion that the inner edge of a lintel creates the tzuras hapesach. Since in such a scenario the inner edge is not over the lechayayim the eruv is pasul. I am indebted to Rabbi Moshe Yitzchok Bernson and Rabbi Elimelech Kornfeld, who pointed out the need to cite these two opinions of the Chazon Ish.

12. Imrei Yosher vol. 2, no. 133. See also Rabbi Gedalya Felder's Yesodei Yeshurun - Ma'areches Lamed Tes Melachos (Yerushalayim, 1976) vol. 2, pp. 282-283.

13. Emek Bracha, Sukkah no. 18.

14. Sha'arei Zion vol. 1, no.3.

15. Orach Chaim, Eruvin 71:10. See also Halachos of the Eruv Chap. VI, G:2 and footnote 39; and Nesivos Shabbos, ibid., and footnotes 94-95. It should be noted that the Chazon Ish is regarded as the primary source of practical psak halacha in matters of eruvin.

16. Orach Chaim 363:113. See also Hilchos Eruvin 4:19 and footnote 100.

17. Shabbos 5a.

18. Eruvin 5b. See also Har Tzvi, ibid. no. 18:1. There are rare exceptions to this rule. See Chazon Ish, Orach Chaim, Eruvin 70:15-16.

19. Another relevant case is that of an overhead cable passing through the foliage of a tree. The tree can be viewed as a lechi. Many Poskim rule that the cable may pass through a lechi. See footnote 2 above. See, however, Nesivos Shabbos, ibid., who notes the concern that over time the branches of the tree may bend the cable away from its correct direct path. See Section 3 above. See also Hilchos Eruvin 4:20-25 for an extensive discussion of tzuros hapesach that pass over structures such as trees, houses and other blockages. Rabbi Tzvi Pesach Frank in Har Tzvi, ibid., no. 18:10 is lenient in cases where the cable runs over or rests on a tree (he does not discuss the case of a cable running through a tree).

20. Orach Chaim no. 291.

21. Eruvin 11a. See, however, Hilchos Eruvin 4:3, footnote 59 and footnote 3 above for possible exceptions to this rule.

22. Hilchos Eruvin, ibid. In footnote 1 we noted that it is hard to apply the concept of she'ashadechak in our day. Rabbi Lange's sefer was written for orthodox soldiers who do often face she'as hadechak situations in the course of duty. Rabbi Lange therefore makes a special effort to identify opinions l'kulla. Opinions that he feels that one should, if possible, not rely upon, should be avoided in constructing an eruv in Chutz La'Aretz. The opinion of the Avnei Nezer in this regard may be an exception because of the strength of his arguments. The Chasam Sofer and other Poskim do not require a full ten tefachim, but only that the lechayayim extend somewhat above the fence or hedge. See Nesivos Shabbos 19:19 and footnotes 43-44.

23. Insuring an interrupted line is a little tricky when riverbanks used as mechitzos are interrupted by bridges. The lechayayim of the tzuras hapesach used to cross the bridge must be within three tefachim of the banks. See Nesivos Shabbos 19:16, footnote 36.

24. See Halachos of the Eruv Chap. VII, A:1-2. In Part 2, Section 6 we will discuss the principle of omed merubeh al haparutz k'omed dami that allows us to regard any break in the wall of a city of ten amos or less as if it were closed. The allowability of breaks and gaps of up to ten amos in a tzuras hapesach eruv is a big question in the Poskim. See Nesivos Shabbos 14:15, footnote 33 and 19:16, footnote 37. The Nesivos Shabbos in the latter footnote quotes the Biur Halacha, Orach Chaim 363:6 d.h. Tzarich who advises inclining l'chumra in this matter. The Nesivos Shabbos infers from this that b'she'as hadechak one may be lenient. Even, however, were one to be satisfied with a she'as hadechak eruv (see footnote 1 above) of this sort, this principle could not apply to the case in question here. The principle of omed merubeh used to allow breaks of less than ten amos applies only to cases where the two structures of omed merubeh are in line and do not overlap. Here, the two structures have overlapped and crossed over each other. They must now double back, so to speak, and meet each other (fig. 12, lefthand side). This is not a case of omed merubeh crossing and closing a gap. This is a case where there is no gap, thus by definition eliminating any application of omed merubeh al haparutz. Here we must connect two structures, which must therefore be within lavud of each other.

25. Orach Chaim, Eruvin 70:21. See also Kehillos Ya'akov, Eruvin no. 6, Hilchos Eruvin 4:21, and Nesivos Shabbos 19:18 and footnote 42.

26. This is even true where the tzuras hapesach is not actually bisected, as long as the lechayayim are outside the area of the enclosure (fig. 12). We have discussed fences and structures that bisect tzuros hapesach. The Chazon Ish, Orach Chaim, Eruvin 70:19 notes that structures that run parallel and within four tefachim of a tzuras hapesach may invalidate the eruv. If these structures are outside the area enclosed by the eruv they do not present a problem. If, however, they are inside that area, then the character of the "door way" is negated - because it opens into too small an area to be considered an "enclosed area." See Hilchos Eruvin 4:25.

27. Shulchan Aruch, Orach Chaim 358:3; Hilchos Eruvin 3:7-12, 7:1-2.

28. Shulchan Aruch, ibid., 358:1.

29. Eidus L'Yisroel, p.151. See Yesodei Yeshurun, ibid., pp. 276-278 for a brief overview of the history of eruvin in Manhattan in which many relevant sources are cited. Perhaps the most exhaustive treatment of the subject is to be found in Rabbi M. M. Kasher's Divrei Menachem, Orach Chaim vol. 2.

30. 82:9 and the Kuntres Acharon there.

31. Orach Chaim 363:28. The Magen Avraham there states that the walls that surround three sides of a courtyard (a "mavoi") cannot be considered the lechayayim for a tzuras hapesach on the courtyard's fourth side. The Magen Avraham does not explain the rationale for his ruling (see Nesivos Shabbos 19:17, footnote 39). A possible interpretation of the Magen Avraham's positionis that lechayayim cannot exceed a certain maximum shiur. See the Chazon Ish, Orach Chaim, Eruvin 70:16. (This Chazon Ish is discussed at length in Hilchos Eruvin 4:12 and footnotes 77-78, but I am not sure that the author depicts the cases presented by the Chazon Ish accurately.) raises the possibility that in certain cases the maximum shiur is three or four tefachim. Under normal circumstances, however, it seems that the maximum shiur is four amos. See Nesivos Shabbos, ibid., footnote 40, in the name of the Makor Chaim. Structures that long are no longer viewed as the "door posts" (lechayayim) of a "door frame" (tzuras hapesach) - they are walls. Elevated train line embankments or overpasses that are more than four amos long would therefore not be halachically suitable to serve as lechayayim. The Chelkas Ya'akov 1:166.4 presents arguments that would allow the use of "long" lechayayim such as embankments that support elevated train lines. His reasoning and proofs, however, are controversial and difficult to follow, and seem not to be in accordance with the opinions of the Poskim mentioned previously in this paragraph.

32. Chazon Ish, Orach Chaim, Eruvin 111:5 derives this ruling from the Magen Avraham mentioned in the previous note. The Chazon Ish there discusses several basic issues in Hilchos Eruvin. These include why we do not place mezuzos on a tzuras hapesach and why utility poles that were not constructed for an eruv may later be used to create one without any physical tikkunim. The Chazon Ish there also presents a significant kulla. He allows distinct features of an overpass or structure (such as support girders and beams) to be used as part of a tzuras hapesach even if they were originally constructed le'achzukai tikra - to support the roof - which is problematic in Hilchos Mezuza. He proves this from the sugya of pischei shima'ei, from the Biur HaGra, Orach Chaim 630:2 and other sources. I am indebted to Rabbi Shlomo Miller and Rabbi Elimelech Kornfeld for directing me to this Chazon Ish.

33. Eruvin 94b.

34. Orach Chaim 361:2.

35. Igros Moshe, Orach Chaim, vol. 1, no. 138.

36. One of my Rabbeim brought evidence that a roof cannot serve as tzuras hapesach from an observation that in Eruvin 94b Rav and Shmuel argue whether the roof of an achsadra (a shelter consisting of a roof supported by poles and no more than two walls) allows one to carry beneath it on Shabbos because of pi tikra yored v'sosem or not. Neither Amora entertains the seemingly obvious possibility of tzuras hapesach. The Chazon Ish cited above in note 32 brings this proof as well. The Nesivos Shabbos 19:17, end of footnote 39, discusses the possibility of using an overhang or ridge on a roof (fig. 14) as the lintel of a tzuras hapesach. He reasons that this is permissible where such a feature - and accompanying lechayayim - are at the edge of the roof. This would apply to an overhang on an overpass or elevated train line. Where the overhang is at the edge of the overpass it may be incorporated in an eruv. Cases where only a lechi is under the extension of a roof are problematic. See Halachos of the Eruv Chap. VII, J and footnote 20. The edge of the overhang may be considered a pi tikra, effectively cutting off the lechi from the rest of the eruv (fig. 15).

37. Shulchan Aruch, Orach Chaim 358:9. See also Hilchos Eruvin 7:3-15; Yesodei Yeshurun, ibid., pp. 261-265; She'arim Metzuyanim B'Halacha 83:4-6 and the Kuntres Acharon there; Tzitz Eliezer 13:41; and Nesivos Shabbos 12-13. The halachos of karpaf are amazingly complex. Many Acharonim have written teshuvos on the subject, and they often vehemently disagree with each other in deciding halacha l'ma'aseh.

38. Orach Chaim 358:11. See also Mishna Berura there no. 85 and the Sha'ar HaTziyunnos. 80-81. It seems from the Rashba's language that although in our times we rarely use pond or stream water for these purposes, nevertheless, where water is theoretically suitable for those purposes it is not considered a karpaf. This would still exclude polluted or dirty bodies of water.

39. Quoted in the Biur Halacha, Orach Chaim 358:9, d.h. Aval Im Nizra. The Chacham Tzvi, no. 59, also cited there by the Biur Halacha, extended the Dvar Shmuel's leniency even to cases where a tzuras hapesach preceded the development of a karpaf (such as a planted field) within its perimeter. In the specific case discussed by the Chacham Tzvi, however, other mitigating factors were involved. See also Nesivos Shabbos 13:15 and footnote 50.

40. Vol. 4 no. 3.

41. In Hilchos Eruvin 4:14, footnote 168, Rabbi Lange notes that the Biur Halacha, ibid., d.h. HaZera'im Mevatlim HaDira would apparently disagree with the Divrei Malkiel. Rabbi Lange therefore says that one may rely on the Divrei Malkiel's heter only "b'dochak gadol." We have already noted that it is difficult to conceive of a she'as hadechak in Chutz La'Aretz.

42. See, for example, The Detroit Eruv, pp. 17-18.

43. See Nesivos Shabbos, all of chap. 23; Noam, vol. 21, pp. 42-92; and Tzitz Eliezer 14:90.

44. See Nesivos Shabbos 15:37 and footnote 37.

45. See Shemiras Shabbos K'Hilchasa 17:25 and footnote 109; vol. 3 p. 29 and 1:29 and footnote 118. Rabbi Yehoshua Neuwirth advises telling those one is sure will listen that the eruv is down. Rabbi Shlomo Zalman Auerbach, however, seems inclined toward the shemu'a in the name of Reb Chaim.

46. Rabbi Hershel Schachter in HaPardes, year 63, 1:3. He does not discuss the principle of Mis'asek, but the similar concept that unintentional transgressions of Rabbinic prohibitions (Shogeg bidi'Rabbanan) do not require Teshuva. A discussion of this topic may be found in Asvan D'Orysa siman 10.

47. Yam shel Shlomo, Bava Kamma 38a.

48. Unfortunately, even smaller eruvin are not problem free. See, for example, articles by Rabbi Yosef Wikler in the Summer 1988 and June 1991 issues of Kashrus Magazine that discuss the many problems that frequently arise in bungalow colony eruvin.

49. A good "How To" guide describing in detail (down to where to buy materials!) many practical solutions to various problems that arise in the construction of urban eruvin is Dr. Bert Miller's The Baltimore Eruv (Baltimore, 1981).

Converted by Andrew Scriven

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