מלכים ב כ:כ פירוש: רש״י

And how he made the pool, etc. In Divrei Hayomim.²⁴See II Divrei Hayomim 32:3-4 and 30. When Sancheiriv began his march on Yerusholayim, Chizkiyohu closed off all the springs and streams outside Yerusholayim as a defensive strategy.