During the Yom Kippur Mussaf service, we always go over the Avodah of the Cohen Gadol. One part has always confused me. The Cohen Gadol makes a point to daven that for the Anshei Sharon, that their homes not become their graves. The Artscroll explains that the earth in Sharon was not suitable for construction, and that frequent flash floods and mudslides would require rebuilding their houses twice every seven years. I am wondering why people kept moving back there and insisted in living in such a place when there are many safer places in Eretz Yisrael to be living. Also, does the area described still exist? Is there a significance to rebuilding twice in seven years (I know this is the metric many people use for Tefillin and Mezuzahs, and wondered if it is a coincidence)?

The source that mentions the prayer of the Cohen Gadol is the Yerushalmi Masechet Yoma Ch.5, halacha 2 and there is additional reference to the impermanence of the houses of the Sharon plain in the Mishna Masechet Sotah ch.8 (discussed in the Bavli Sotah 33-34). The problem was that because the Sharon is a flat plain, the rain water didn’t drain properly and eroded the foundations of the buildings (Korban Haeda on Yoma). Another explanation was that the land was not suited for making bricks (Rashi Sotah 43a). It would seem that the danger involved, while real, was not severe enough to prohibit settling the area- which, because the Sharon is part of the Land of Israel, is of course a Mitzva. The cities of Herzliya and Netanya, among others are located today on the Sharon plain. The problems of drainage have been mostly solved- although in recent rains some low-lying areas of Tel Aviv were evacuated because of flooding. The dangers today in the cities of the Sharon are from other sources- terrorism and the threat of missile attack. With G-d’s help, these too will be overcome.