Desalination in the Gaza Strip: drinking water supply and environmental impact

More than 90% of the population of the Gaza Strip depends on desalinated water for drinking purposes. About 90% of the groundwater is unacceptable for drinking as a result of contamination by nitrate and chloride. One of the major options for resolving the water problems is the utilization of desalination technology for both sea and brackish water. The objective of this article is to address desalination water management in its embryonic stage in the Gaza Strip. The sources of drinking water supply, distribution system and the environmental impact of brine water will be fingered in detail. Desalination facilities range from large seawater plants to small brackish desalination units on a home scale. Governmental, non-governmental and private desalination plants are common. The distribution system of desalinated water is a responsibility of governmental, non-governmental, private small community bodies and even individuals. Disposal of brine water is made either directly or indirectly into the sea, sewage system, poor land, channels, wadies, etc. Brine constituents have an adverse impact on the surrounding environment, e.g., sea life, soil, wastewater treatment plants and the groundwater aquifer. The lack of real environmental impact assessments, especially for mid- and homescale units may lead to a deterioration of the environment. The fragmentation of the responsibilities of water desalination, distribution of desalinated water and the disposal of brine water suggest that urgent action should be taken (e.g., legislation or establishment of a supervisory body). In other words, strict policies and management actions are to be taken in order to alleviate the health and environmental impact of an important and uncontrolled new system.

The Gaza Strip is a narrow small area in which groundwater is the only source of water; its shortage is becoming an increasingly urgent problem as water quantity and quality problems are quite vital in the area. The high population growth rate is causing heavy increasing demand on water resources. The demand for potable water significantly exceeds the available supply in the Gaza Strip. As the water table falls, saltwater from the Mediterranean and nearby saline aquifers are introduced into the Gaza aquifer. Therefore, one of the major options for the remedy of the water shortage in the Gaza Strip is the utilization of desalination technology for brackish water and seawater. Management of desalinated water is rather difficult because of the fragmentation of the responsible bodies. Desalination is considered a very important option for meeting the rapidly growing demands for fresh water and mitigating the environmental problems associated with over-extraction of the aquifer. More than 90% of the population in the Gaza Strip depends on desalinated water as the only source for drinking. There are several sources from which the population can get desali- nated water, e.g., government, non-government and private desalination plants. Additionally, home-scale desalination units are widespread. The distribution system of desalinated water is quite complex because it is not well organized or fully supervised by the authorities. Brine has a very high concentration of salt and other toxic chemical compounds. Disposal of brine is a primary environmental issue associated with desalination processes. Normally, 60 to 70% of intake water is rejected. Large desalination plants discharge brine into the sea, while small private desalination plants and household RO units discharge brine into the sewage network. The environmental impact includes, but is not limited to: (a) impact on the seawater, (b) impact on soil, (c) impact on the aquifer and last but not least (d) impact on the sewage system. The government and people recognize that both brackish and seawater desalination plants are very important to maintain as an alternative water source in the Gaza Strip, but brine management is a very important issue to consider, especially since there is a wide distribution of desalination plants either in the private and public sector.