Water issues in developing countries

The article on water issues in of developing countries includes information on scarcity of drinking-water, poor infrastructure for water access, floods and droughts, and the contamination of rivers and large dams in developing countries. Over one billion people in developing countries have inadequate access to clean water. Millions of women spend hours everyday collecting water, 2.6 billion people lack access to sanitation, and 1.8 million children die each year from diarrhea.[1] Barriers to addressing water problems in developing nations include poverty, education, climate change, and poor governance.

Rising demand

Woman washing at water's edge in Bangladeshi Village

People need fresh water for personal care, agriculture, industry, and commerce. The 2019 UN World Water Development report notes that about 4 billion people, representing nearly two-thirds of the world population, experience severe water scarcity during at least one month of the year.[2] With rising demand, the quality and supply of water diminishes.[3]

Water use has been increasing worldwide by about 1% per year since the 1980s. Global water demand is expected to continue increasing at a similar rate until 2050, accounting for an increase of 20-30% above 2019 usage levels.[2] The steady rise in use has principally been led by surging demand in developing countries and emerging economies. Per capita water use in the majority of these countries remains far below water use in developed countries—they are merely catching up.[2]

Agriculture (including irrigation, livestock, and aquaculture) is by far the largest water consumer, accounting for 69% of annual water withdrawals globally. Agriculture's share of total water use is likely to fall in comparison with other sectors, but it will remain the largest user overall in terms of both withdrawal and consumption. Industry (including power generation) accounts for 19% and households for 12%.[2]

Availability and access

The scarcity of fresh water resources is an issue in arid regions around the world, but is becoming more common due to overcommitment of resources.[4] In the case of physical water scarcity, there is not enough water to meet demand. Dry regions do not have access to fresh water in lakes or rivers while access to groundwater is sometimes limited.[4] Regions most affected by this type of water scarcity are Mexico, Northern and Southern Africa, the Middle East, India, and Northern China.[4]

Economic water scarcity applies to areas that lack the fiscal resources and/or human capacity to invest in water sources and meet local demand. Water is often only available to those who can pay for it or those in political power, leaving millions of the world's poorest without access. Regions most affected by this type of scarcity are portions of Central and South America, Central Africa, India, and Southeast Asia.[4]

Case Studies

India

India's growing population is putting a strain on the country's water resources. The country is classified as "water stressed" with a water availability of 1,000-1,700 m3/person/year.[5] In 2008, 88% of the population had access and was using improved drinking water sources.[6] "Improved drinking water source" is an ambiguous term, ranging in meaning from fully treated and 24-hour availability to merely being piped through the city and sporadically available.[7] This is in part due to large inefficiencies in the water infrastructure in which up to 40% of water leaks out.[7]

In UNICEF's 2008 report, only 31% of the population had access and used improved sanitation facilities.[6] A little more than half of the 16 million residents of New Delhi, the capital city, have access to this service. Every day, 950 million gallons of sewage flows from New Delhi into the Yamuna River without any significant forms of treatment.[7] This river bubbles with methane and was found to have a fecal coliform count 10,000 times the safe limit for bathing.[7]

Surface water contamination, due to lack of sewage treatment and industrial discharge, makes groundwater increasingly exploited in many regions of India.[7] This is aggravated by heavily subsidized energy costs for agriculture practices[7] that make up roughly 80% of India's water resource demand.[8]

To illustrate the sheer challenge of improving water quality: in India, 80% of the health issues come from waterborne diseases.[9] Part of this challenge includes addressing the pollution of the Ganges (Ganga) river, which is home to about 400 million people.[10] The river receives about over 1.3 billion litres of domestic waste, along with 260 million litres of industrial waste, run off from 6 million tons of fertilizers and 9,000 tons of pesticides used in agriculture, thousands of animal carcasses and several hundred human corpses released into the river every day for spiritual rebirth. Two-thirds of this waste is released into the river untreated.[10]

Kenya

Kenya, a country of 36.6 million, struggles with a staggering population growth rate of 2.6% per year.[11] This high population growth rate pushes Kenya's natural resources to the brink of total depletion. Much of the country suffers from a severely arid climate, with a few areas enjoying rain and access to water resources. Deforestation and soil degradation have polluted surface water, and the government does not have the capacity to develop water treatment or distribution systems, leaving the vast majority of the country without access to water. This has exacerbated gender politics, as 74% of women must spend an average of 8 hours per day securing water for their families.[12]

The growing population and stagnant economy have exacerbated urban, suburban, and rural poverty. It also has aggravated the country's lack of access to clean drinking water which leaves most of the non-elite population suffering from disease. This leads to the crippling of Kenya's human capital.[13]

Private water companies have taken up the slack from Kenya's government but the Kenyan government prevents them from moving into the poverty-stricken areas to avoid profiteering activities.[12] Unfortunately, since Kenya's government also refuses to provide services, this leaves the disenfranchised with no options for obtaining clean water..

Bangladesh

Historically, water sources in Bangladesh came from surface water contaminated with bacteria. Drinking infected water resulted in infants and children suffering from acute gastrointestinal disease that led to a high mortality rate.[14]

During the 1970s, UNICEF worked with Department of Public Health Engineering to install tube-wells. Tube-wells draw water from underground aquifers to provide a safe source of water for the nation. As of 2010, 67% of Bangladeshis had a permanent water source and a majority of them used tube wells.[15]

The wells consist of tubes 5 cm in diameter inserted less than 200 m into the ground and capped with an iron or steel hand pump. At that time, standard water testing procedures did not include arsenic testing.[14] This lack of precaution led to one of the largest mass poisoning of a population because the ground water used for drinking was contaminated with arsenic.[16] Intervention measures such as awareness programs and the painting of tube-wells red if the water is above the government limit of 50 ppb arsenic (green otherwise) have been effective in preventing further poisoning.

Available options for providing safe drinking water include deep wells, traditionally dug wells, treatment of surface water, and rainwater harvesting.[17] Between 2000 and 2009, more than 160,000 safe water devices have been installed in arsenic-affected regions of Bangladesh.[18]

Contamination

After accounting for availability or access, water quality can reduce the amount of water for consumption, sanitation, agriculture, and industrial purposes. Acceptable water quality depends on its intended purpose: water that is unfit for human consumption could still be used in industrial or agriculture applications. Parts of the world are experiencing extensive deterioration of water quality, rendering the water unfit for agricultural or industrial use. For example, in China, 54% of the Hai River basin surface water is so polluted that it is considered un-usable.[19]

Safe water is one of the eight Millennium Development Goals: between 1990 and 2015 to "reduce by half the proportion of the population without sustainable access to safe drinking water and basic sanitation." Even having access to an ‘improved water source’ does not guarantee the water's quality, as it could lack proper treatment, become contaminated during transport or home storage.[20] A study by the World Health Organization (WHO) found that estimates of safe water could be overestimated if accounting for water quality, especially if the water sources were poorly maintained.[21]

Runoff from development along the river in Pune, India could contribute to reduced water quality.

Specific contaminants of concern include unsafe levels of biological pollutants and chemical contaminants, including

  • metals, including iron and arsenic
  • organic matter
  • salts
  • viruses
  • bacteria
  • protozoa
  • parasites[19][20]

These contaminants can lead to debilitating or deadly water-borne diseases, such as fever, cholera, dysentery, diarrhea and others.[20] UNICEF cites fecal contamination and high levels of naturally occurring arsenic and fluoride as two of the world's major water quality concerns. Approximately 71% of all illnesses in developing countries are caused by poor water and sanitation conditions.[22] Worldwide, contaminated water leads to 4,000 diarrhea deaths a day in children under 5.[23]

UNICEF notes that non-harmful physical qualities of water, such as color, taste, and smell, could cause water to be perceived as poor quality and deemed un-usable by its intended users.[24]

Child standing next to a well pump in a Bangladeshi Village. Many such wells have naturally high levels of arsenic.

The volume of contaminants can overwhelm an area's infrastructure or resources to treat and remove them. Cultural norms and governance structures can also contribute further reduction or water quality. Water quality in developing countries is often hampered by lack of or limited enforcement of:

  • emission standards
  • water quality standards
  • chemical controls
  • non-point source controls (e.g. agricultural runoff)
  • market based incentives for pollution control/water treatment
  • follow-up and legal enforcement
  • integration with other related concerns (solid waste management)
  • trans-boundary regulation on shared water bodies
  • environmental agency capacity (due to resources or lack of political will)
  • understanding/awareness of issues and laws [25]

Beyond human health and ecosystem health, water quality is important for various industries (such as power generation, metals, mining, and petroleum) which require high-quality water to operate. Less high quality water (either through contamination or physical water scarcity) could impact and limit the choices of technology available to developing countries. Reductions in water quality have the dual effect of not only increase the water stress to industrial companies in these areas but typically also apply increasing the pressure to improve the quality of the industrial wastewater.[19]

However, gaps in wastewater treatment (the amount of wastewater to be treated is greater than the amount that is actually treated) represent the most significant contribution to water pollution and water quality deterioration. In the majority of the developing world, most of the collected wastewater is returned to surface waters directly without treatment, reducing the water's quality.[26] In China, only 38% of China's urban wastewater is treated and although 91% of China's industrial waste water is treated, it still releases extensive toxins into the water supply.[19]

The amount of wastewater treatment possible can also be compromised by the networks required to bring the wastewater to the treatment plants. It is estimated that 15% of China's wastewater treatment facilities are not being used to capacity due to a limited pipe network to collect and transport wastewater. In São Paulo, Brazil, a lack of sanitation infrastructure results in the pollution of the majority of its water supply and forces the city to import over 50% of its water from outside watersheds. Polluted water increases a developing country's operating costs, as lower quality water is more expensive to treat. In Brazil, polluted water from the Guarapiranga Reservoir costs $0.43 per m3 to treat to usable quality, while water from the compared to only $0.10 per m3 for water coming from the Cantareira Mountains.[19]

Improving water resources

Improving access

To address water scarcity, organizations focus on increasing the supply of fresh water, mitigating its demand, and enabling reuse and recycling.[27] In 2011 the World Health Organization revised its Guidelines for Drinking-water Quality. This document, written for an audience of water and/or health regulators and policy-makers, is intended to aid in the development of national drinking water quality standards. The guidelines include health based targets, water safety plans, surveillance, and supporting information regarding the microbial, chemical, radiological, and acceptability aspects of common drinking water contaminants. In addition, the document offers guidance regarding the application of the drinking water quality guidelines in specific circumstances, including large buildings, emergencies and disasters, travelers, desalination systems, planes and ships, packaged drinking water, and food production.[28]

According to the WHO, "The most effective means of consistently ensuring the safety of a drinking-water supply is through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from catchment to consumer. In these Guidelines, such approaches are called water safety plans (WSPs)". A WSP is a plan that will ensure the safety and acceptability of a drinking-water supply. The Water Safety Plan Manual, published in 2009 by the WHO and the International Water Association, offers guidance to water utilities (or similar entities) as they develop WSPs. This manual provides information to help water utilities to: assess their water system, develop monitoring systems and procedures, manage and community their plan, carry out periodic review of the WSP, and to review the WSP following an incident. The WSP manual also includes three case studies drawn from WSP initiatives in three countries/regions.[29]

Wello

Wello, a social venture, developed the WaterWheel to improve global access to water. The WaterWheel is a non-mechanical wheel enabling one person to transport 25 gallons (90 litres) of water, enough water for one family, in a single trip. A WaterWheel user can put up to 200 pounds (90 kg) of water in the "wheel", a broad drum with round edges and a steel handle, transforming the water to an effective weight of approximately 22 pounds (10 kg). The design allows for easy maneuvering over different terrains, inclines, and corners. By reducing the number of daily trips needed to collect water, the WaterWheel allows women and children in developing countries to devote more time and energy to educational and economic activities. In addition, the WaterWheel is a sustainable solution for water transportation. It does not require any energy or other supplies in order to operate. It also does not require repairs over its 10-15 year life.[30]

Reclaimed water

Utilizing wastewater from one processes to be used another in another process where lower-quality water is acceptable is one way to reduce the amount of wastewater pollution and simultaneously increase water supplies. Recycling and reuse techniques can include the reuse and treatment of wastewater water from industrial plant wastewater or treated service water (from mining) for use in lower quality uses. Similarly, wastewater re-use in commercial buildings (e.g. in toilets) and use of treated municipal wastewater (e.g. for industrial cooling).[19]

Purification

AQUAtap Community Drinking Water Stations

Quest Water Solutions’ AQUAtap Drinking Water Station is a simple system that uses solar power to purify contaminated groundwater, brackish water, or sea water into safe drinking water. The systems are powered by photovoltaic panels. Each Drinking Water Station is fully autonomous and can purify water at a rate of up to 20,000 litres per day without any existing infrastructure. They are also modular, so can be scaled for increased water purification. In addition, the system includes a distribution system.[31]

In 2012, Quest Water Solutions started construction of an AQUAtap Drinking Water System in Bom Jesus, an Angolan village 50 kilometers east of Luanda, the capital of Angola. The 500 residents of Bom Jesus currently rely on a dirty river for drinking water. The clean drinking water produced by the AQUAtap will be available to villagers at no cost to the villagers.[32]

HydroPack

The HydroPack, developed by Hydration Technology Innovations (HTI), is a one-time use, self hydrating, emergency hydration pouch. Victims of natural disasters often struggle to find clean drinking water. Water sources and drinking water supplies are often contaminated during a disaster; victims often suffer from water borne illnesses. The HydroPack is a 4-inch by 6-inch pouch filled with electrolytes and nutrients. When in contact with water, the HydroPack swells to create a healthy drink in 10 to 12 hours. "It doesn’t matter what the quality of water is like", says Keith Lampi, vice president and chief operating officer for HTI. "There just needs to be a source of water, even dirty or brackish water, and we can supply clean drinks at the initial stages of a disaster using the HydroPacks."[33]

The HydroPack is a 12 fluid ounce (355 millilitre) pouch with two compartments that are separated by a membrane. One side of the pouch includes a sports drink syrup. The user places the pack in a water source for 10 to 12 hours. During that time untreated water diffuses across the membrane and dilutes the sports drink syrup. The HydroPack uses Forward Osmosis, a natural equilibrium process that rejects even the harshest of contaminants. The technology does not clog and can be used in very turbid water. The pouch includes a straw and the resulting nutrient drink is very palatable. According to HTI, "HTI's products are not meant to displace other bulk water strategies such as ROWPUs, municipal water systems, or shipboard desalination and bottling. Instead, they should play a very critical role in the early phase of disaster relief until other production and distribution strategies can be put in place." This technology also reduces the weight of aide materials needed to be transported after a disaster. One pallet of 94,500 HydroPacks weighs 8,325 pounds (3,785 kg) and will produce 12,482 gallons (47,250 litres) of clean drink. This equates to about a 92% reduction in weight compared to bottled water. HydroPack were distributed to earthquake survivors in the tent city of Carrefour in Haiti in 2010.[34]

Global programs

UN-Water

In 2003, the United Nations High Level Committee on Programmes created UN-Water, an inter-agency mechanism, "to add value to UN initiatives by fostering greater co-operation and information-sharing among existing UN agencies and outside partners." UN-Water publishes communication materials for decision-makers that work directly with water issues and provides a platform for discussions regarding global water management. They also sponsor World Water Day (http://www.unwater.org/worldwaterday/index.html) on March 22 to focus attention on the importance of freshwater and sustainable freshwater management.[35]

The Water Project

The Water Project, Inc is a non-profit organization that develops and implements sustainable water projects in Kenya, Rwanda, Sierra Leone, Sudan, and Uganda. The Water Project has funded or completed over 250 projects that have helped over 125,000 people improve their access to clean water and sanitation.[36]

ACP-EU Water Facility

Established in 2004, the ACP-EU Water Facility received money from the European Development Fund to sponsor projects that improve water quality and sanitation and improve water management governance in African, Caribbean, and Pacific (ACP) countries.[37]

Improving Water Quality

Despite the clear benefits of improving water sources (a WHO study showed a potential economic benefit of $3–34 USD for every $1 USD invested), aid for water improvements have declined from 1998 to 2008 and generally is less than is needed to meet the MDG targets. In addition to increasing funding resources towards water quality, many development plans stress the importance of improving policy, market and governance structures to implement, monitor and enforce water quality improvements.[38]

Contaminant Reduction through Policy & Market Improvements

Reducing the amount of pollution emitted from both point and non-point represents a direct method to address the source of water quality challenges. Pollution reduction represents a more direct and low-cost method to improve water quality, compared to costly and extensive wastewater treatment improvements.[26]

Various policy measures and infrastructure systems could help limit and reduce water pollution in developing countries. These include:

  1. Improved management, enforcement and regulation for pre-treatment of industrial and agricultural waste, including charges for pollution[25]
  2. Policies to reduce agricultural run-off or subsidies to improve the quality and reduce the quantity needed of water polluting agricultural inputs (e.g. fertilizers)
  3. Limiting water abstraction during critical low flow periods to limit the concentration of pollutants
  4. Strong and consistent political leadership on water[25]
  5. Land planning (e.g. locating industrial sites outside the city) [25]

Water treatment options

Large Scale Water Treatment

Current technology enables us to solve this with a variety of solutions to increase the supply; we can convert non-freshwater to freshwater by treating water pollution (Woltersdorf, 2018).[39] Much of water’s physical pollution includes organisms, metals, acids, sediment, chemicals, waste, and nutrients. Water can be treated and purified into freshwater with limited or no constituents through certain processes (Tebbutt, 1998).[3]

Common Large Scale Water Treatment Technologies:

  • Distillation - The processes of water distillation are solely defined by the similar processes of desalination units, thermal evaporation, and condensation. It involves the process of vaporization of a substance at determined boil to convert water from its liquid state into vapor then subsequently condense it back into liquid; separating itself from the initially concentrated particles and effluent (D'Souza, n.d.).[40] The same concept proceeds with any other type of contaminated water. This process provides consistent purified water that is separated from contaminants rather than directly filtered, yet has drawbacks on mechanical maintenance, costs on electricity, and concentrates with lower boiling points have to be filtered separate from the system.[40] In water distillation, water is heated to its boiling point, resulting in condensation and separates itself from any of its concentrated impurities, many of which are commonly chemical constituents of lead, copper, municipal fluoride, chlorine, and other minerals and chemicals. Distillers produce fresh water free of contaminants, along with some particle residue.[40] Some of these particles are minerals ideal for the human body, making it viable drinking water.[40] Distilled water is also utilized in common mechanical applications including the topping off of lead acid batteries capacity, non-corrosive cooling for heat exchange in systems such as jacket water in engines and automotive vehicles, or water-cooling systems in computers.[41] Although it is ideal, as a result of molecular interactions between chemicals such as inter-molecular forces, most distillation systems lack actual 100.00% removal of unwanted constituents that may still be present, much of which is fluoride.[40] In that, distillation is rather notable for its high energy consumption rates and is increasingly being replaced by current membrane technologies, specifically reverse osmosis (RO) membranes as RO's are more energy efficient for water desalination (Manish Kumar, Tyler Culp, & Yuexiao Shen, 2016).[41]
  • Reverse Osmosis - One of the popular commercial competitors with water distillation, which is commonly referred to as one of the main filtration methods, is reverse osmosis.[41] Reverse osmosis membrane technology has been reliable and developed for about 50 years and is the leading technology for desalination today.[42] Reverse osmosis is a biological process used for the removal of dissolved solids within water (Greenlee, 2009).[42] By use of water pressure and a filter instead of chemical or mechanical systems, this particular water treatment system is more energy efficient than when compared to distillation.[41] In the beginning of installation, reverse osmosis is known to be competitive with distillation in making purified water for human consumption.[41] Reverse osmosis is done by filtration of effluent materials from the water molecules such as most dissolved salts, bacterium, organics, and common constituents like chlorine and fluoride via high pressured water. This pressured water is sent through a cross-filtration system that prevents build up between filters. These specialized filters are known as semipermeable membranes that only let particular molecules to travel through, allowing direct filtration of salt from seawater. Reverse osmosis systems use kinetic energy of incoming water pressure instead of electricity to allow the passage of the water through these filters, pushing out water and leaving the contaminants behind.[41] On top of mitigating the energy costs, primary RO unit management is simple because the filters just need to be replaced on a yearly basis. On the adverse side, as a result of impermanence, the membranes can age with wear and tear on the pores, allowing some viruses, bacteria, pharmaceuticals, pesticides and other contaminants to pass through them.[42]

Point of use and small scale treatment

Various innovations exist to effectively treat water at the point of use for human consumption. Studies have shown point of use treatment to reduce diarrhea mortality in children under 5 by 29%. Home water treatment solutions may not be widely considered in development strategies, as they are not recognized under the water supply indicator in the United Nations' Millennium Development Goals. Various challenges may reduce the effectiveness of home treatment solutions, such as low education, low-dedication to repair and replacement, or local repair services or parts are unavailable.[20]

Current point of use and small scale treatment technologies include:

  • NaDCC, sodium dichloroisocyanurate
  • Boiling water
  • Solar disinfection (SODIS)
  • Chlorine


See also

References

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