Identification
Bible commentator Matthew Henry erroneously identified the Pool of Siloam with the Pool of Bethesda and conjectured that the tower of Siloam may have been supporting one of the five porches of the Pool of Bethesda mentioned in the Gospel of John, and that the 18 victims were killed by the falling porch. This was discredited when the real Pool of Bethesda was discovered in north Jerusalem.
Other Bible commentators have speculated that the tower of Siloam may have been part of a Roman aqueduct connected to the Pool of Siloam. At least two aqueducts are known to have carried water to the pool from the Gihon Spring, but these aqueducts were built into the ground, not on elevated viaducts requiring towers.
It has also been speculated that the tower was a fortress built to defend the city, similar to the Phasael tower.
Read more about this topic: Tower Of Siloam