NORMAN GOLB argues in The Forward that the recently discovered escape tunnel in Jerusalem may have been used to evacuate Dead Sea Scrolls. Excerpt:

Putting the various statements of the archaeologists and of Josephus together, we have the following picture:

The archaeologists have discovered a Jerusalem tunnel that could accommodate many individuals and which led, at the least, from the Temple Mount to the Siloam Pool situated in the southern extremity of the ancient city. The pool, in turn, led directly to the Nahal Qidron, which, as the news reports indicate, led eastward down to the Dead Sea.

While no description in Josephus’s “Jewish War” actually makes mention of a particular locus, he does indeed state that various inhabitants of Jerusalem hid in the city’s underground passages (plural), and at one point he describes an important group of rebels whom he calls “the tyrants” as having secured temporary refuge in “the ravine below Siloam,” by which he undoubtedly means the opening gorges of the Nahal Qidron. It is thus a fair inference or assumption on the part of the archaeologists that the tunnel they uncovered was one of those used by Jerusalem’s inhabitants to hide and flee from the Romans. However, if we follow Josephus, not only one but several escape routes could be and were used by the refugees. No available indications appear to confirm the archaeologists’ suggestion that the drain-tunnel discovered by them is a particular one uniquely referred to by Josephus.

Tunnels of this type, moreover, were discovered by explorers of Jerusalem’s past in the 19th-century; see particularly the accounts given by Charles Warren in his 1876 “Underground Jerusalem” and the four illustrations reproduced in reduced form here.

Warren’s findings, together with the discovery of Reich and Shukron described in the recent news reports, fully support Josephus’s statements relating to the tunnels beneath Jerusalem and the use to which they were put during the Roman siege of 70 A.D. These underground passages enabled many inhabitants of Jerusalem to exit the city and flee both south to Masada and, via Nahal Qidron and other wadis heading from Jerusalem eastward toward the Dead Sea, to the Machaerus fort lying just east of that sea, and which was actually closer to Jerusalem than was Masada. (Josephus describes the large number of refugees who gathered at Machaerus.)

The circumstances as now known leave little doubt that, quite likely beginning even before the siege had begun, groups engaged in hiding the Temple treasures, the books and other items listed in the Copper Scroll — as well as those ancient writings of the Palestinian Jews known as the Dead Sea Scrolls, which were found centuries later in caves near the wadis leading out of Jerusalem.

Interesting idea, which builds on Golb's theory that the Dead Sea Scrolls were literary archives from Jerusalem rather than a sectarian library. (See here, here, and here.)