This is not exactly news — it is something that I discovered serendipitously a couple of years ago — but it’s new enough that it was not included in my ca. 2007 article on this topic, which I have now updated (and re-posted in PDF format).
This concerns a section of Jerusalem’s Lower Aqueduct which lies at the eastern edge of today’s Jewish Quarter in the Old City, roughly opposite the southwestern corner of the Haram al-Sharif/Temple Mount. It is right where one descends the southern staircase leading toward the Western Wall area. If you’ve visited Jerusalem, perhaps you’ve walked right past it without realizing it — as I did dozens of times!
Here is the general location: The channel is visible in the cliff-face just below this building, which faces the southwest corner of the the Haram/TM…
Here are the visible remains, seen in cross-section where the bedrock of the western hill scarp broke away (or was cut away). Note the tall rock-hewn channel, which experts say dates from the Hasmonean period, plus the two segments of terra-cotta pipe, a 16th-century Ottoman-Turkish addition inserted into the ancient channel.
The following map shows the Lower Aqueduct in it’s 1st century context: After following the west bank of the Hinnom and crossing the valley on a bridge (left), it looped around the southern end of the western hill (Josephus’ “Upper City” and today’s “Mount Zion”) and entered the city, beneath the walls (center). The segment highlighted here (red markings) was carrying water — always purely by gravity, all the way from Solomon’s Pools! — northward along the scarp. Turning east, it then traversed the ancient “Wilson’s Arch” bridge over the Tyropoeon Valley, finally discharging it’s flow into the great cisterns lying beneath the platform of the Temple Mount.
Here are additional views of the remains at this particular site: