Wouldn’t Joseph Smith have thought that all “rivers” have water?

In 1 Nephi 2:6 we read:

And it came to pass that when he had traveled three days in the wilderness, he pitched his tent in a valley by the side of a river of water.

Why would Joseph Smith say “river of water”? Book of Mormon Online responds:

According to Hunter and Ferguson, it is only in the springtime that most of the stream beds in Palestine and the desert by the Gulf of Aqaba contain water. In fact, the writers note that the Hebrew language has one word, “nahar”, for “river of water” (see 1 Nephi 2:6) and another for the dry stream bed, “nachal.” [Milton Hunter and T. Stuart Ferguson, Ancient America and the Book of Mormon, p. 77]
– Book of Mormon Online – Lehites in Jerusalem and Arabia

Wouldn’t we expect Joseph Smith to have simply said Lehi pitched his tent by the side of a river? Where would Joseph Smith have learned so much about Arabia?

See:

Book of Mormon Online – Lehites in Jerusalem and Arabia

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