Desalination is a process that takes away mineral components from saline water. More generally, desalination is the removal of salts and minerals from a target substance, as in soil desalination, which is an issue for agriculture. Saltwater is desalinated to produce water suitable for human consumption or irrigation. The by-product of the desalination process is brine. Desalination is used on many seagoing ships and submarines. Most of the modern interest in desalination is focused on cost-effective provision of fresh water for human use. Along with recycled wastewater, it is one of the few rainfall-independent water resources.
Gwadar is a port city on the southwestern coast of the Pakistani province of Balochistan. The city is located on the shores of the Arabian Sea, opposite Oman and has a population of over 90,000, according to the 2017 census. It was an overseas possession of Oman from 1783 to 1958. It is about 120 km (75 mi) southwest of Turbat. The sister port city of Chabahar in Iran's Sistan and Baluchestan provinces is about 170 km (110 mi) to the west of Gwadar. On 2 April 2021, it was declared the capital of the south Balochistan region.
Water supply and sanitation in Hong Kong is characterized by water import, reservoirs, and treatment infrastructure. Though multiple measures were made throughout its history, providing an adequate water supply for Hong Kong has met with numerous challenges because the region has few natural lakes and rivers, inadequate groundwater sources, a high population density, and extreme seasonable variations in rainfall. Thus nearly 80 percent of water demand is met by importing water from mainland China, based on a longstanding contract. In addition, freshwater demand is curtailed by the use of seawater for toilet flushing, using a separate distribution system. Hong Kong also uses reservoirs and water treatment plants to maintain its source of clean water.
Water supply and sanitation in Singapore are intricately linked to the historical development of Singapore. It is characterised by a number of outstanding achievements in a challenging environment with geographical limitations. Access to water in Singapore is universal, affordable, efficient and of high quality.
The Gwadar Port is situated on the Arabian Sea at Gwadar in Balochistan province of Pakistan and is under the administrative control of the Maritime Secretary of Pakistan and operational control of the China Overseas Port Holding Company. The port features prominently in the China–Pakistan Economic Corridor (CPEC) plan, and is considered to be a link between the Belt and Road Initiative and the Maritime Silk Road projects. It is about 120 kilometres (75 mi) southwest of Turbat, and 170 kilometres (110 mi) to the east of Chabahar Port.
A reverse osmosis plant is a manufacturing plant where the process of reverse osmosis takes place. Reverse osmosis is a common process to purify or desalinate contaminated water by forcing water through a membrane. Water produced by reverse osmosis may be used for a variety of purposes, including desalination, wastewater treatment, concentration of contaminants, and the reclamation of dissolved minerals. An average modern reverse osmosis plant needs six kilowatt-hours of electricity to desalinate one cubic metre of water. The process also results in an amount of salty briny waste. The challenge for these plants is to find ways to reduce energy consumption, use sustainable energy sources, improve the process of desalination and to innovate in the area of waste management to deal with the waste. Self-contained water treatment plants using reverse osmosis, called reverse osmosis water purification units, are normally used in a military context.
Mekorot is the national water company of Israel and the country's top agency for water management. Founded in 1937, it supplies Israel with approx. 80% of its drinking water and operates a cross-country water supply network known as the National Water Carrier. Mekorot and its subsidiaries have partnered with numerous countries around the world in areas including desalination and water management.
The Perth Seawater Desalination Plant, located in Naval Base, south of Perth, Western Australia, turns seawater from Cockburn Sound into nearly 140 megalitres of drinking water per day, supplying the Perth metropolitan area.
Water supply and sanitation in Saudi Arabia is characterized by challenges and achievements. One of the main challenges is water scarcity. In order to overcome water scarcity, substantial investments have been undertaken in seawater desalination, water distribution, sewerage and wastewater treatment. Today about 50% of drinking water comes from desalination, 40% from the mining of non-renewable groundwater and only 10% from surface water in the mountainous southwest of the country. The capital Riyadh, located in the heart of the country, is supplied with desalinated water pumped from the Persian Gulf over a distance of 467 km. Water is provided almost for free to residential users. Despite improvements, service quality remains poor, for example in terms of continuity of supply. Another challenge is weak institutional capacity and governance, reflecting general characteristics of the public sector in Saudi Arabia. Among the achievements is a significant increases in desalination, and in access to water, the expansion of wastewater treatment, as well as the use of treated effluent for the irrigation of urban green spaces, and for agriculture.
The Victorian Desalination Plant is a water desalination plant in Dalyston, on the Bass Coast in southern Victoria, Australia. The project was announced by Premier Steve Bracks in June 2007, at the height of the millennium drought when Melbourne's water storage levels dropped to 28.4%, a drop of more than 20% from the previous year. Increased winter-spring rains after mid-2007 took water storage levels above 40%, but it was not until 2011 that storages returned to pre-2006 levels.
Peak water is a concept that underlines the growing constraints on the availability, quality, and use of freshwater resources. Peak water was defined in 2010 by Peter Gleick and Meena Palaniappan. They distinguish between peak renewable, peak non-renewable, and peak ecological water to demonstrate the fact that although there is a vast amount of water on the planet, sustainably managed water is becoming scarce.
The Sydney Desalination Plant also known as the Kurnell Desalination Plant is a potable drinking water desalination plant that forms part of the water supply system of Greater Metropolitan Sydney. The plant is located in the Kurnell industrial estate, in Southern Sydney in the Australian state of New South Wales. The plant uses reverse osmosis filtration membranes to remove salt from seawater and is powered using renewable energy, supplied to the national power grid from the Infigen Energy–owned Capital Wind Farm located at Bungendore.
Water supply and sanitation in Israel are intricately linked to the historical development of Israel. Because rain falls only in the winter, and largely in the northern part of the country, irrigation and water engineering are considered vital to the country's economic survival and growth. Large scale projects to desalinate seawater, direct water from rivers and reservoirs in the north, make optimal use of groundwater, and reclaim flood overflow and sewage have been undertaken. Among them is the National Water Carrier, carrying water from the country's biggest freshwater lake, the Sea of Galilee, to the northern part of the Negev desert through channels, pipes and tunnels. Israel's water demand today outstrips available conventional water resources. Thus, in an average year, Israel relies for about half of its water supply on unconventional water resources, including reclaimed water and desalination. A particularly long drought in 1998–2002 had prompted the government to promote large-scale seawater desalination. In 2022, 85% of the country's drinkable water was produced through desalination of saltwater and brackish water.
The Adelaide Desalination plant (ADP), formerly known as the Port Stanvac Desalination Plant, is a sea water reverse osmosis desalination plant located in Lonsdale, South Australia which has the capacity to provide the city of Adelaide with up to 50% of its drinking water needs.
The Claude "Bud" Lewis Carlsbad Desalination Plant is a desalination plant in Carlsbad, California, north of the Encina Power Station. The San Diego County Water Authority (SDCWA), the recipient of the fresh water produced by the plant, calls it "the nation’s largest, most technologically advanced and energy-efficient seawater desalination plant." Opened on December 14, 2015, the entire desalination project cost about $1 billion for the plant, pipelines, and upgrades to existing SDCWA facilities to use the water.
Australia is the driest habitable continent on Earth and its installed desalination capacity has been increasing. Until a few decades ago, Australia met its demands for water by drawing freshwater from dams and water catchments. As a result of the water supply crisis during the severe 1997–2009 drought, state governments began building desalination plants that purify seawater using reverse osmosis technology. Approximately one percent of the world's drinkable water originates from desalination plants.
The Minjur Desalination Plant is a reverse osmosis, water desalination plant at Kattupalli village, a northern suburb of Chennai, India, on the coast of the Bay of Bengal that supplies water to the city of Chennai. Built on a 60-acre site, it is the largest desalination plant in India. Construction works were carried out by the Indian company IVRCL and the Spanish company Abengoa, under the direction of the Project Manager Fernando Portillo Vallés and the Construction Manager Juan Ignacio Jiménez-Velasco, who returned to Europe after the inauguration of the plant to work on renewable energy projects. Originally scheduled to be operational by January 2009, the work on the plant was delayed due to Cyclone Nisha in October 2008, which damaged a portion of the completed marine works and destroyed the cofferdam meant for the installation of transition pipes. The trial runs were completed in June 2010 and the plant was opened in July 2010. Water from the plant will be utilised chiefly for industrial purposes such as the Ennore Port and North Chennai Thermal Power Station. However, during droughts, water from the plant will be supplied to the public, serving an estimated population of 1,000,000.
Drinking water supply and sanitation in Algeria is characterized by achievements and challenges. Among the achievements is a substantial increase in the amount of drinking water supplied from reservoirs, long-distance water transfers and desalination at a low price to consumers, thanks to the country's substantial oil and gas revenues. These measures increased per capita water supply despite a rapidly increasing population. Another achievement is the transition from intermittent to continuous water supply in the capital Algiers in 2011, along with considerable improvements in wastewater treatment resulting in better water quality at beaches. These achievements were made possible through a public-private partnership with a private French water company. The number of wastewater treatment plants throughout the country increased rapidly from only 18 in 2000 to 113 in 2011, with 96 more under construction. However, there are also many challenges. One of them is poor service quality in many cities outside Algiers with 78% of urban residents suffering from intermittent water supply. Another challenge is the pollution of water resources. There has also been insufficient progress concerning reuse of treated water, a government priority in this dry country.
China–Pakistan Economic Corridor (CPEC) is a 3,000 km Chinese infrastructure network project in construction in Pakistan. This sea-and-land-based corridor is aimed to secure and reduce the passage for China's energy imports from the Middle East, by avoiding the existing route from the Straits of Malacca between Malaysia and Indonesia, which, in case of war could be blockaded, and thus hamper the Chinese energy-dependent economic avenues. Developing a deep water port at Gwadar in the Arabian Sea and a well built road and rail line from this port to Xinjiang region in western China would be a shortcut for boosting the trade between Europe and China. In Pakistan, it aims to overcome an electricity shortfall, infrastructural development and modernize transportation networks. Along with shifting it from an agricultural based economic structure to industrial based.
There are approximately 16,000 operational desalination plants, located across 177 countries, which generate an estimated 95 million m3/day of fresh water. Micro desalination plants operate near almost every natural gas or fracking facility in the United States. Furthermore, micro desalination facilities exist in textile, leather, food industries, etc.
