Beijing is situated on the northern tip of the North China Plain and lies adjacent to Tianjin and Hebei Province. The city is located in a very flat part of the country surrounded by mountains to the west and north-west. Its long history dates back 3,000 years and is closely interlinked with water. In Beijing municipality there are 21 million inhabitants, with an average growth of 580,000 inhabitants/year. The urban population amounts to 18.6 million inhabitants. The city covers a total area of 16,410 km2 with an urban area of 1,368 km
The Buenos Aires Metropolitan Area (AMBA) is home to 12.8 million inhabitants (2010) and covers 2,500 km2, stretching along the Rio de la Plata, an immense river with a flowrate of 23,000 m3/s. The city also extends across a plain endowed with a large groundwater supply. AMBA encompasses the City of Buenos Aires and 24 surrounding municipalities within the Province of Buenos Aires. A main challenge for its water and land management is the lack of a metropolitan authority.
The City of Chicago is the third-largest city in the United States and is home to 8.3 million people. It is situated 179 m above sea level in a metropolitan region that has a continental climate with warm summers, cold winters and an average annual precipitation of 937 mm.
Ho Chi Minh City
Ho Chi Minh City (HCMC) covers 2,096 km2 and is home to almost 10 million inhabitants (8.1 million according to the 2014 census), and one of the most important megacities in South-East Asia. The city’s population grows at about 3% per year, resulting in major socio-economic and demographic changes. Since 2000, about 16 km2 of this territory has been urbanized every year. The urban area has exceeded its administrative borders and HCMC has become the centre of a metropolitan area of 19 million inhabitants.
The city of Kinshasa, capital of the Democratic Republic of the Congo, is located on the left bank of the Congo River in front of the city of Brazzaville, capital of the Republic of Congo. Its latitude is 4° 19' 39’’ South and its longitude is 15° 18' 48'' East. It has the administrative status of a Province.
Lagos State, Nigeria’s largest city, is located in the south-western region of Nigeria, and encompasses an area of 3,577 km2. Lagos sits on a coastal plain characterized by flat terrain at an average elevation of 15 m above sea level. Water bodies and wetlands cover over 40% of the total land area. The population of Lagos State was 17.5 million in 2006 with a growth rate of 3.2%. It is one of the fastest growing cities in the world and in 2015 the population was estimated at 23.3 million. The city has 57 local government administrative units.
London is the largest urban area and capital city of the United Kingdom, with a population of 8.6 million and a forecast of 11 million by 2050. Its economy is based on service industries, while the city itself is one of the world’s leading financial centres. London enjoys a good transport infrastructure and the average life expectancy of residents is high. It is also a major tourist destination, often cited as the most visited city in the world
The City of Los Angeles (LA) has 4 million residents and forms the economic centre of the greater LA area, which is inhabited by 13 million people. The city is located along the Pacific Ocean in Southern California and is known for its warm climate, beautiful beaches and as the centre of the American entertainment industry.
The Mexico City Metropolitan Area (MCMA) occupies much of the Mexico Valley Basin. It is at once the capital of the country and its political, economic, religious and commercial hub. The basin, closed in its natural state, is bounded in the four cardinal directions by mountain ranges, so that precipitation within it generates rivers, streams and springs, whose waters flows into five large permanent lakes and several smaller ones, extending to the lower reaches of the valley
Mumbai is the largest city in India. A large part of this megacity was reclaimed from the sea when the seven original islands were joined together, with the result that most of the city is at sea level. In 2011, the population of Mumbai reached 12.4 million. It had a high rate of growth, but is now showing signs of stabilization. Fifty-six percent of the citizens of Mumbai live in slums.
New York City (NYC) has the largest unfiltered water supply in the United States. More than 9 million customers and visitors rely on three extensive reservoir systems, including 19 reservoirs and three controlled lakes, which hold a storage capacity of nearly 2.2 trillion litres. This system was meticulously designed as an interconnected network that has ensured a flexible, reliable and resilient supply of drinking water for more than a century. Rain water and wastewater is conveyed via a 12,070-km network of sanitary storm and combined storm sewers, and treated by 14 large municipal wastewater treatment plants. Currently, longrange planning and adaptive management efforts are being undertaken by the city to address the challenging impacts of a growing population, aging infrastructure and climate change.
Greater Paris, considered as the continuous built-up area around the city, has 10.5 million inhabitants. It can be considered an old megacity that grew denser at its centre in the nineteenth century and at the periphery following the Second World War. It is located in a temperate climate that is relatively dry, with 650 mm of rainfall/year well distributed all year round.
The development and rapid industrialization of the Republic of Korea in the 1960s and 1970s saw people move to the Seoul Metropolitan Area (Seoul and satellite cities) seeking decent jobs and better opportunities for their future. Today, the total population amounts to approximately 20 million, accounting for almost half of the country.
Water and wastewater service in Tokyo dates back to the 1890s, approximately 130 years ago. Facilities have been expanded continuously to keep up with the population’s desire for improved services. The city’s water-related offices have struggled to provide the best possible service, while confronting new challenges from climate change and natural disasters. Currently, water-related services cover a population of approximately 13 million and an area of 1,239 km2. Service coverage is 100% from 11 water purification plants and 20 wastewater treatment plants.
Manila is situated on the plain of the Pasig River that flows into Manila Bay. The city has a tropical climate with mean temperatures ranging from 20°C to 38°C. Metro Manila, comprising 17 municipalities, covers an area of about 636 km2. The total urban area has a population of 24 million, while the estimated population density is 19,130 persons/km2, one of the highest in the world.
Istanbul is the only city located on the continents of both Asia and Europe, and has served for centuries as the capital of three empires. Today, it is the commercial and financial centre of the Turkish Republic, and has an urban population of around 15 million. The city was founded under the name of Constantinople around BC 659, and its first major water structures were built during the Roman Period. It then became the capital of the Byzantine Empire, which focused on the construction of cisterns throughout the city. Following the conquest of Constantinople in 1453, the Ottoman Empire developed a unique water civilization, including the rehabilitation of historic water structures, the usage of aqueducts for water flow and the construction of four dams.