2 Chronicles 32:1-5

After Hezekiah had faithfully carried out this work, King Sennacherib of Assyria invaded Judah. He laid siege to the fortified towns, giving orders for his army to break through their walls. When Hezekiah realized that Sennacherib also intended to attack Jerusalem, he consulted with his officials and military advisers, and they decided to stop the flow of the springs outside the city. They organized a huge work crew to stop the flow of the springs, cutting off the brook that ran through the fields. For they said, “Why should the kings of Assyria come here and find plenty of water?” Then Hezekiah worked hard at repairing all the broken sections of the wall, erecting towers, and constructing a second wall outside the first. He also reinforced the supporting terraces in the City of David and manufactured large numbers of weapons and shields.