Shortages of fresh water for Palestinians in the Gaza Strip are compounded by lack of sewerage. John Lewis recently returned from three months as a humanitarian observer, where he wrote this report.
Historic Palestine is fed by a single river, the Jordan, which is shared with Syria, Lebanon and Turkey, as well as the dry Kingdom of Jordan.
There are a few seasonal streams, but rainfall is low along the coast.
There is little enough water to go round.
In the Palestinian Territories - the West Bank and Gaza Strip - the total water consumption for all purposes is about 75 litre/day per person. In Israel proper, consumption of water averages about 350 litre/day per person.
The 1.2M population who live in 40km long, 8km wide Gaza Strip face severe problems.
The flat sandy area, along the Mediterranean seashore, has water bearing rock formations below the sand, but they lie below sea level. As fresh water is drawn up through wells, salty Mediterranean water is migrating inland and gradually contaminating the wells.
In 2002 a water assessment scheme funded by US agency US Aid and carried out by the Palestine Hydrology Group found that the Strip is now using up the water supply at about three times the rate at which rainfall can replenish it. In some places saltwater is within 20m of the surface, and in others wells have had to be closed because the water is unusable for any purpose.
At the moment, 95% of people are drinking water beyond limits recommended by the World Health Organisation (WHO). Agriculture is failing because well water is already too saline.
At the current population growth and water consumption rates, in 20 years there will be no drinkable water in the Gaza Strip, the US Aid report predicts. There is insufficient water on adjacent Israeli territory to pipe in water, even if Israel were willing. Egypt could not sell water from the Nile because it is also needed by Ethiopia and Sudan.
That leaves desalination as the only solution. The American government has agreed to build a desalination plant and to pay running costs for a short period.
But a single desalination plant will make up only about a quarter of the current shortfall, and given the poverty of the area there is no prospect of this district being able to pay for operating the plant when American funding runs out.
To make the situation worse, there is no general sewerage system and effluent runs through the sand into water bearing geological layers which supply the wells. Right across the Gaza Strip people are being forced to pump water from deeper and deeper levels to avoid contamination.
And in the northern Bedouin Village, which sits in a depression, a great lake of untreated sewage has collected, seeping into the aquifer. Locals now make no attempt to use well water at all in this village, but children cannot be entirely kept away from it, goats drink it, and it is crawling with mosquitoes. The level is rising.
John Lewis was stationed in the Gaza Strip by the Quakers as part of the organisation's remit to observe and report on conflict zones.