Unexpected underground stream uncovered

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I first posted about this dramatically deep hole a year ago (here and here).
Since then this new tunnel has been started on the southern side of the shaft.
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Here's the northern side.
Someday a high speed train will run between Jerusalem and Tel Aviv and it will enter Jerusalem through these tunnels.
The big underground central train station will double as a bomb shelter.
It is between the busy Central Bus Station and Binyanei HaUma convention center.
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Meanwhile, a few days ago (and just in time for ABC Wednesday U-Day), a great discovery hit the news:
An unexpected underground stream was uncovered at a depth of 75 meters, five meters from the planned bottom of the shaft!
"The largest and most impressive underground water sources ever discovered in Israel," scholars say.
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The karstic cave developed as water seeped in from the surface and dissolved the limestone.
It is between a half a meter to a few meters wide, and is a few dozen meters high and at least 200 meters long.
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Prof. Amos Frumkin, Head of the Cave Research Unit at Hebrew University, said the cave also has hydrological significance because it is part of the mountain aquifer, an underground reservoir into which rainwater flows from the surface and that extends all along Israel's central mountain range. "The study of the cave can help us understand the precise mechanism by which water flows through the aquifer in the Jerusalem area."
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TV news showed him and a few lucky colleagues squeezing through nooks and crannies and crawling in mud. Brave explorers they are.
And I imagine the first humans to enter this cave!
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Frumkin says the cave must be protected as a valuable natural phenomenon and that this can be accomplished without impeding construction of the railway station.
That is good news!
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Read more details in the Haaretz article.
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UPDATE: A newer and better article has become available at JPost.
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