Masada: Herod's Water System

Masada has no spring, and the annual rainfall comes to less than 100 mm., a fifth of what Jerusalem gets. Yet Herod the Great stored 40,000 cubic meters of water (about 10 million gallons) in cisterns in the sides of the mountain. Where did it come from? And why did he need so much?

Where did the water come from?

About a tenth of the supply came from the rain that fell here. On entering from the east, we can see that the central part of the plateau dips and narrows in our direction. Herod's architect gathered the run-off and led it to a cistern on the mountain's east side (visible upon leaving the cable car), by means of a drainage canal (also visible).

Yes, but where did the other 36,000 cubic meters come from?

To answer this, we need to combine a little information with what we can see from the western side.

Information: It rains little here indeed, but it rains five times as much or more along the peak of the Judean mountain block from Jerusalem to Hebron. Half of this water flows downhill to the east -- into the desert, whose surface is chalk. At the touch of moisture, the molecules of the chalk swell up, becoming waterproof. The water flows on the surface, uniting and forming mighty flash floods near the Dead Sea a few hours later. (See photo below. For a biblical reference to these, see 2 Kings 3:4-27.)

Map: the pattern of the rain.

The modern Dead Sea road, damaged by a flash flood.

What we can see: Looking west from Masada, we can see a gorge. Here Herod's engineers built a dam to catch the floods.

Near the top of the gorge they attached an aqueduct. They also dug and plastered cisterns in the western side of the mountain. (We can see them from above or visit them from the Roman ramp.) They placed these over an abyss, high enough to be beyond an attacker's reach but low enough to catch the water, which flowed by gravity through the aqueduct. One cistern filled, the overflow would go into its neighbor, and so on. In fact, they dammed two gorges (the other is around the corner of the cliff to the north) creating two such systems.

Map of the desert fortresses

People would have to descend to the cisterns and bring the water up (to more cisterns on the plateau). For this purpose Herod had slaves. He provided them with a secret staircase and a wall, so that no one standing west of the abyss could see them.

An enemy could destroy the aqueduct! Indeed, but what good would it do them? The defenders of Masada would already have water enough in the mountain, much more than the besiegers. Until the Romans arrived in 73 AD, no major army had ever been able to stay for long in the desert.

How then did the besieging Romans, with ten or fifteen thousand soldiers, solve their water problem? After putting down the Jewish revolt in 70 AD, they had so many prisoners and pack animals, they could form a "bucket brigade" from springs in the Tse'elim river three miles to the north. We can still see the path of the "brigade."

Again, the view to the north, emphasizing the Roman water sources.

Why did Herod need so much water?

Early in his career, Herod and his family had fled to Masada for refuge. Because of the mountain's strength, the family was able to hold out while he traveled to Rome and back, a year's journey. At one point they were desperately short of water, but a rainstorm saved them.

Impressed with the natural defenses, Herod decided to turn it into his bunker of last resort. If his enemies ever got the upper hand, all he would have to do was reach Masada. Here he could live out the rest of his natural life without "turning on the news." The southern part of the mountain was free, Josephus tells us, for agriculture. The water, therefore, wasn't only for drinking, but to ensure a permanent food supply. Here we have, then, a little isle of self-sufficiency.

Masada: Introduction

Young Herod and Masada

The Herodian structures on Masada

The Northern Palace

The Water Supply

The Build-up to the First Revolt Against Rome

Masada's Water Supply

Masada and the Jewish revolt against Rome

The Synagogue on Masada

Logistics for Masada