TEMPLE MOUNT WATCH:

Temple Aqueduct and Ritual Bath Excavated Opposite Temple Mount
01:00 Jan 15, '07 / 25 Tevet 5767
by Ezra HaLevi (Arutz Sheva)

Excavations being conducted opposite the Western Wall Plaza have uncovered an aqueduct that brought water to the Holy Temple, as well as a ritual bath from that period.


The never-before-excavated area is situated behind the Western Wall police station, adjacent to the plaza where millions of worshipers and tourists come each year to visit the Western Wall and Temple Mount.

The new archaeological find uncovers a missing link in the ancient water system, known as the "Lower Aqueduct" which channeled water from Solomon’s Pools near Bethlehem (located miles south of Jerusalem) directly to the national focal point of Jewish worship - the Temple Mount.

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UPDATE: The Jerusalem Post also has a story on the excavation that includes additional information:

Invading Romans' greatest obstacle uncovered in J'lem
By ETGAR LEFKOVITS

An immense bedrock cliff uncovered opposite Jerusalem's Temple Mount may help explain why it took the Romans so long to capture what is now known as the Jewish Quarter almost two millenia ago, an Israeli archeologist said Sunday.

The cliff, uncovered during a year-long excavation at the western edge of the Western Wall Plaza, was one of several important finds that include the remains of a colonnaded street called the Eastern Cardo, dating from the Roman-Byzantine period; a section of the Lower Aqueduct that conveyed water from Solomon's Pools to the Temple Mount; and a damaged rock-hewn and plastered Jewish mikve (ritual bath) that dates back to the Second Temple period, the Israel Antiquities Authority announced at a press conference.

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And there's also a report by the Israel Ministry of Foreign Affairs that looks as though it's the source of the Arutz Sheva article.