Water supply and sanitation in Mexico is characterized by achievements and challenges. Among the achievements is a significant increase in access to piped water supply in urban areas as well as in rural areas between 1990 and 2010. Additionally, a strong nationwide increase in access to improved sanitation was observed in the same period. Other achievements include the existence of a functioning national system to finance water and sanitation infrastructure with a National Water Commission as its apex institution; and the existence of a few well-performing utilities such as Aguas y Drenaje de Monterrey.
Water scarcity is the lack of fresh water resources to meet the standard water demand. Water scarcity can be also caused by droughts lack of rainfall or pollution. This was listed in 2019 by the World Economic Forum as one of the largest global risks in terms of potential impact over the next decade. It is manifested by partial or no satisfaction of expressed demand, economic competition for water quantity or quality, disputes between users, irreversible depletion of groundwater, and negative impacts on the environment. Two-thirds of the global population live under conditions of severe water scarcity at least 1 month of the year. Half a billion people in the world face severe water scarcity all year round. Half of the world's largest cities experience water scarcity.many of people have problems with water scarcity.
While Peru accounts for about four per cent of the world's annual renewable water resources, over 98% of its water is available east of the Andes, in the Amazon region. The coastal area of Peru, with most of economic activities and more than half of the population, receives only 1.8% of the national freshwater renewable water resources. Economic and population growth are taking an increasing toll on water resources quantity and quality, especially in the coastal area of Peru.
Water resources management is a significant challenge for Mexico. Furthermore, water management is imposing a heavy cost to the economy. The arid northwest and central regions contain 77% of Mexico's population and generate 87% of the gross domestic product (GDP). By contrast, the poorer southern regions have abundant water resources ;however, surface and groundwater are overexploited and polluted thus leading to an insufficient water availability to support economic development and environmental sustainability. The country has in place a system of water resources management that includes both central (federal) and decentralized institutions.
Mexico, a classified arid and semi-arid country, has a total land area of 2 million square kilometres, 23% of which is equipped for irrigated agriculture. The agricultural sector plays an important role in the economic development of the country accounting for 8.4 of agricultural gross domestic product (GDP) and employing 23% of the economically active population. Irrigated agriculture contributes about 50% of the total value of agricultural production and accounts for about 70% of agriculture exports. Mexico's government initiated a number of structural reforms in the water sector aimed to introduce modern water management and irrigation.
Water resources management is a key element of Brazil's strategy to promote sustainable growth and a more equitable and inclusive society. Brazil's achievements over the past 70 years have been closely linked to the development of hydraulic infrastructure for hydroelectric power generation and just recently to the development of irrigation infrastructure, especially in the Northeast region.
Water resources are natural resources of water that are potentially useful. Uses of water include agricultural, industrial, household, recreational and environmental activities. All living things require water to grow and reproduce.
The water resources management system in Uruguay has been influenced by the general sense of water as an abundant resource in the country. Average annual rainfall is 1,182 mm, representing a contribution of 210 km3 annually throughout its territory. In 2002, the per capita renewable water resources was 41,065 cubic meters, way above the world average 8,467 m3 in 2006. Uruguay also shares one of the largest groundwater reserves in the world, the Guarani Aquifer, with Brazil, Argentina, Paraguay. The Guarani aquifer covers 1,200,000 square kilometers and has a storage capacity of 40,000 km3.
With surface water resources of 20 billion m3 (BCM) per year, of which 12 BCM are groundwater recharge, water resources in the Dominican Republic (DR) could be considered abundant. But irregular spatial and seasonal distribution, coupled with high consumption in irrigation and urban water supply, translates into water scarcity. Rapid economic growth and increased urbanization have also affected environmental quality and placed strains on the DR's water resources base. In addition, the DR is exposed to a number of natural hazards, such as hurricanes, storms, floods, Drought, earthquakes, and fires. Global climate change is expected to induce permanent climate shocks to the Caribbean region, which will likely affect the DR in the form of sea level rise, higher surface air and sea temperatures, extreme weather events, increased rainfall intensity and more frequent and more severe "El Niño-like" conditions.
As Australia's supply of freshwater is increasingly vulnerable to droughts, possibly as a result of climate change, there is an emphasis on water conservation and various regions have imposed restrictions on the use of water.
Greater Mexico City, a metropolitan area with more than 19 million inhabitants including Mexico's capital with about 9 million inhabitants, faces tremendous water challenges. These include groundwater overexploitation, land subsidence, the risk of major flooding, the impacts of increasing urbanization, poor water quality, inefficient water use, a low share of wastewater treatment, health concerns about the reuse of wastewater in agriculture, and limited cost recovery. Overcoming these challenges is complicated by fragmented responsibilities for water management in Greater Mexico City:
Beginning early in the 20th century, Monterrey, Mexico began a successful economic metamorphosis and growth pattern that remains an exception in Mexico. This all began with increased investments in irrigation that fueled a boom in agriculture and ranching for this northern Mexican city. The economic growth has fueled income disparity for the 3.86 million residents who live in the Monterrey Metro area (MMA). In addition, the rapid urbanization has taken a large toll on the water resources. In addressing many of this challenges, the city of Monterrey has become a model for sound and effective Integrated urban water management.
Integrated urban water management in Aracaju, the capital city of the Brazilian State of Sergipe (SSE) has been and still is a challenging prospect. Home to half a million people, Aracaju is located in a tropical coastal zone within a semi-arid state and receives below average rainfall of 1,200 mm/year where average rainfall in Latin America is higher at 1,556 mm/yr. Most of the residents do have access to the potable water supply and non-revenue water losses are nearly 50%.
Water resources management in Syria is confronted with numerous challenges. First, all of the country's major rivers are shared with neighboring countries, and Syria depends to a large extent on the inflow of water from Turkey through the Euphrates and its tributaries. Second, high population growth and urbanisation increase the pressure on water resources, resulting in localized groundwater depletion and pollution, for example in the Ghouta near Damascus. Third, there is no legal framework for integrated water resources management. Finally, the institutions in charge of water resources management are weak, being both highly centralized and fragmented between sectors, and they often lack the power to enforce regulations. Water resources policies have been focused on the construction of dams, the development of irrigated agriculture and occasional interbasin transfers, such as a pipeline to supply drinking water to Aleppo from the Euphrates. There are 165 dams in Syria with a total storage capacity of 19.6 km³. Demand management through metering, higher tariffs, more efficient irrigation technologies and the reduction of non-revenue water in drinking water supply has received less emphasis than supply management. The government implements a large program for the construction of wastewater treatment plants including the use of reclaimed water for irrigation.
Water resources management in modern Egypt is a complex process that involves multiple stakeholders who use water for irrigation, municipal and industrial water supply, hydropower generation and navigation. In addition, the waters of the Nile support aquatic ecosystems that are threatened by abstraction and pollution. Egypt also has substantial fossil groundwater resources in the Western Desert.
Guatemala faces substantial resource and institutional challenges in successfully managing its national water resources. Deforestation is increasing as the global demand for timber exerts pressure on the forests of Guatemala. Soil erosion, runoff, and sedimentation of surface water is a result of deforestation from development of urban centers, agriculture needs, and conflicting land and water use planning. Sectors within industry are also growing and the prevalence of untreated effluents entering waterways and aquifers has grown alongside.
The global freshwater model WaterGAP calculates flows and storages of water on all continents of the globe, taking into account the human influence on the natural freshwater system by water abstractions and dams. It supports understanding the freshwater situation across the world’s river basins during the 20th and the 21st century, and is applied to assess water scarcity, droughts and floods and to quantify the impact of human actions on freshwater. Modelling results of WaterGAP have contributed to international assessment of the global environmental situation including the UN World Water Development Reports, the Millennium Ecosystem Assessment, the UN Global Environmental Outlooks as well as to reports of the Intergovernmental Panel on Climate Change. They were included in the 2012 Environmental Performance Index which ranks countries according to their environmental performance.
National Water Policy is formulated by the Ministry of Water Resources of the Government of India to govern the planning and development of water resources and their optimum utilization. The first National Water Policy was adopted in September, 1987. It was reviewed and updated in 2002 and later in 2012.
Water scarcity in India is an ongoing water crisis in India that affects nearly 600 million people each year. In addition to affecting the huge rural and urban population, the water scarcity in India also extensively affects the ecosystem and agriculture. India has only 4% of the world’s fresh water resources despite a population of over 1.3 billion people. In addition to the disproportionate availability of freshwater, water scarcity in India also results from drying up of rivers and their reservoirs in the summer months, right before the onset of the monsoons throughout the country. The crisis has especially worsened in the recent years due to climate change which results in delayed monsoons, consequently drying out reservoirs in several regions. Other factors attributed to the shortage of water in India are a lack of proper infrastructure and government oversight and unchecked water pollution.
The Water crisis in Iran refers to the problems regarding water scarcity in Iran. Water scarcity can be a result of two mechanisms: physical (absolute) water scarcity and economic water scarcity, where physical water scarcity is a result of inadequate natural water resources to supply a region's demand, and economic water scarcity is a result of poor management of the sufficient available water resources. Iran's main concerns regarding the water crisis include high climatic variability, poor distribution of water, and prioritization of economic development.
