It was Hezekiah who blocked the upper outlet of the Spring of Gihon and channeled it down to the west side of the City of David. And Hezekiah prospered in all that he did.
KJV
This same Hezekiah also stopped the upper watercourse of Gihon, and brought it straight down to the west side of the city of David. And Hezekiah prospered in all his works.
ASV
This same Hezekiah also stopped the upper spring of the waters of Gihon, and brought them straight down on the west side of the city of David. And Hezekiah prospered in all his works.