Isn’t everything else about Hezekiah, all his heroic acts and how he made the pool and tunnel to bring water into the city, written in the official records of the kings of Judah?
Hezekiah was the one who stopped the water from flowing from the upper outlet of Gihon. He channeled the water directly underground to the west side of the City of David. Hezekiah succeeded in everything he did.
After him Nehemiah, Azbuk’s son, the official in charge of half the district of Beth Zur, made repairs all the way to a point across from the tombs of David as far as the pool and the soldiers’ barracks.