A few years ago, I travelled in south-eastern Spain to give a lecture in the town of Lorca in the Province of Murcia. It has an impressive fortress with an extraordinary history, but I think, the most dramatic thing I observed there was the Guadalentín River (from Arabic meaning "mud river"); a broad expanse with impressive bridges, and lacking only one thing – water.
Lorca is a pretty and interesting town, but the Guadalentín River is strange and somewhat forlorn. When, on rare occasion it floods, it is wild, broad and powerful, like the desert wadis of the Levant. But the bridges make it seem almost like a cruel joke - a river without what makes a river.
Water, it seems, is one of those things one either has too much of, or not enough of. For the past five or so years the Levant has been suffering from poor winter rainfalls. Is it part of the global warming, or merely another of those occasional droughts that arrive every so often in bundles of so many consecutive years, like the fulfilment of a Pharaonic dream? It is a much-debated topic. In Israel, although it has been partly offset by an intensive (if belated) desalination program, the dire effects of this present drought can be observed in the ever-receding inland lakes (or seas, as they are rather wishfully known). An outbreak of Leptospirosis, a disease caused by livestock or wild animals urinating and defecating in water sources, has been regarded as the outcome of poor water flow in streams in the north of the country.
In Jerusalem, the supply of water has always been a matter of considerable importance, certainly in the Crusader period when the population expanded and large numbers of pilgrims seasonally put a strain on its resources. This is not so much because there is a real shortage of rain, but because of the way it generally comes in this part of the world. Winter storms are brief and intense and this means that although the quantity of rainfall may be quite satisfactory, it cannot be properly utilised. It is a not very well-known fact, that the average annual rainfall in Jerusalem, at around 590 mm, is roughly the same as that of London, and only somewhat less than Paris, which has an average of 637 mm. In those regions of Syria that formerly constituted the northern crusader states the rainfall is higher still. Tripoli today has 921 mm and Antioch has as much as 1,121 mm. That is a lot of water, but not of much use if most of it is running off into the sea.
In battle and in siege, the water supply was of paramount importance. The presence or lack of it could effectively turn the dice in favour of one side or the other. Indeed, it was no less important than fortifications. One could surround oneself with massive walls, towers and moats, but if the water supply ran out, the strongest defences would be of no avail. A field army could not campaign effectively on insufficient water, and without water, a besieging army could not maintain a siege. That is why, for example, prior to the crusader siege of Jerusalem in the summer of 1099, the Fatimids, who had a good water supply in open reservoirs and underground cisterns within the city walls, made an effort to block or contaminate all the wells and springs outside the city upon which the crusader army would be dependent. This resulted in a serious shortage of drinking water for the tens of thousands of troops and their horses and livestock. Contemporary source like the Gesta Francorum and Albert of Aachen, describe the dire situation this produced, with water being sold at very high prices. It had to be carried from a source nearly six miles distant and to reach it the soldiers had to pass through dangerous enemy territory. Those who managed to avoid having their heads cut off by Muslims in ambush, returned with water that was stinking, muddied and putrid, and sometimes contained leeches which if swallowed, could cause a very painful death.
For Westerners coming from regions where water availability was generally not major concern, a harsh lesson was learnt during a siege early in the First Crusade. A German contingent passing through Anatolia, besieged and occupied a castle named Xerigordon. It was only when they were inside that the knights made the alarming discovery that the only water supply to the castle was from a well and spring located outside the walls, now under enemy control. When the situation became dire, they bled their horses in order to drink the blood, and drank water from a sewer. After eight days of this, they capitulated, and were given the choice of conversion or death, either one of which, by then, probably seemed like not so bad a deal.