Disruption of water supplies during war is an ancient miliary tactic. Water is used as a weapon in besieged cities, where water supply is either cut off or deliberately polluted to weaken the enemy population.
The armed conflicts recent years have to a large extent taken place in urban areas. The complex infrastructure for both supplying water and for removing waste water are vulnerable to enemy disruption and pose a great challenge to water engineers to provide emergency repairs or emergency supplies. When the civil war in Lebanon led to the disruption of the water supply, residents of individual blocks of houses in west Beirut drilled 3000 m into the ground to tap fresh water. After a while, however, the groundwater level was lowered to such an extent that saltwater was sucked into the wells and all boreholes were useless for freshwater supply. Similarly when the Kurdish people were fleeing Iraqi troops, their only means of water supply was mountain springs. However these springs were frequently mined. Emergency agencies like the International Committee of the Red Cross installed Oxfam water racks along the main roads to provide water for the millions of refugees.
An example of the relationship of conflict and water is on the West Bank. Tens of thousands of Palestinians in tiny villages on the West Bank rely on springs for drinking water. Water experts estimate as many as 120 villages – or about one- fifth of the population – are not connected to a water network. Though Israel handed over parts of West Bank territory to Palestinians in December 1995, it kept control over the sources of underground water. Today, if Palestinians want to drill new wells, they must first get permission from Israel. Palestinians say this in an unfair arrangement that leaves them with less water than the minimum daily amount needed for basic use. By contrast, none of the 144 Israeli settlements that dot the West Bank have water shortages. Most home have gardens and some have swimming pools. Where a Palestinian villager typically uses 50 litres of water per day, settlers use 250.
When water negotiators meet, Palestinians focus almost exclusively on water rights. They blame their own water shortage on the excess consumed by settlers. The Israelis claim that having one control authority for the shared aquifers is the only way to preserve fragile water sources. They accuse Palestinians of damaging the sources by tapping in without permission as soon as Israeli troops vacated the territory. They claim the water shortages of the Palestinians are not due settlements or sovereignty, but simple economics and under- development -- just plain poverty and lack of water resource management.
Malaysia, which supplies about half of Singapore's water, threatened to cut off that supply in 1997 after Singapore criticized its government policies. In Africa, relations between Botswana and Namibia have been severely strained by Namibian plans to construct a pipeline to divert water from the shared Okavango River to eastern Namibia.
Water is becoming an increasingly important element of internal and international conflicts. Many television viewers associate conflict with long queues for water. The siege of Sarajevo will always be remembered by the images of people pushing their wheelbarrows with jerry cans of drinking water.
Disrupting water supply can be a direct weapon in armed conflict. It can also be an indirect consequence of the conflict. For example, in Iraq during the Gulf War, the allied troops bombed all important electrical power stations. As a consequence, both water treatment and sewage pumping were disrupted. Due to the embargo, diesel and spare parts were very scarce. As an indirect consequence, thousands of infants died due to poor hygiene.