Water quality serves as the foundation for almost all development. Contaminated, unsafe water threatens human health, diminishes food production, reduces ecosystem functions, and limits economic growth. Unfortunately, new water quality challenges due to emerging pollutants like pharmaceuticals, pesticides, and industrial and household chemicals exacerbate historical water quality threats, particularly in light of changing climate patterns and their impacts on human health and ecosystems.
A UNESCO fact sheet notes that lack of safely managed sanitation, including sewage treatment (for piped sewers) and fecal sludge management (for on-site sanitation like latrines and septic systems), contributes significantly to water pollution. A reduction of about one-third of the world's biodiversity is estimated to be a consequence of the degradation of freshwater ecosystems due to pollution of water resources.
To improve water quality and quantity, USAID works with its partners to expand watershed protection and restoration and provide support to develop and implement water quality assurance plans as well as water quality monitoring and surveillance. This includes helping water user associations, regulatory agencies, and laboratories to collect water quality data and promote routine monitoring.
This issue contains resources and recent studies that discuss water quality monitoring, water quality and COVID-19, chemical and microbial pollution, household water treatment, and the use of biochar to address chemical pollution of water supplies.
Water and Development Technical Series: Rural Water Services. USAID, May 2020. This brief provides an overview of the important factors to consider when designing a rural water activity and information on the strengths and weaknesses of various possible water service delivery models.
Water and Development Technical Series: Urban Water Services. USAID, October, 2020. Water service delivery in urban areas of developing countries is often fragmented, with people relying on multiple sources for water. This brief describes approaches for improving urban water services, quick wins for improving service in the water sector, and how to measure success. Other technical briefs in the series are available here.
Drinking-Water Quality Guidelines. World Health Organization (WHO), 2017. The fourth edition of the WHO guidelines for drinking water quality builds on more than 50 years of guidance from the organization, which has formed an authoritative basis for the setting of national regulations and standards for water safety in support of public health.
Domestic Water Quantity, Service Level and Health. WHO, December 2020. This second edition reviews the evidence about the relationships among water quantity, water accessibility, and health. The effects of water reliability, continuity, and price on water use are also covered. Updated guidance, including recommended targets, is provided on domestic water supply to ensure beneficial health outcomes.
Drinking Water Fact Sheet. WHO, June 2019. Contaminated water can transmit diseases such diarrhea, cholera, dysentery, typhoid, and polio. Contaminated drinking water is estimated to cause 485,000 diarrheal deaths each year.
Water Quality Monitoring
From Data to Decisions: Understanding Information Flows within Regulatory Water Quality Monitoring Programs. NPJ Clean Water, August 2020. Results suggest that broad reforms are necessary to improve the use of water quality data to manage water safety. These measures could include strengthening enforcement of testing and reporting, building staff capacity for managing and using data, and integrating collection of water quality data with other information systems.
From Data to Decisions: Water Quality Monitoring Programs in Sub-Saharan Africa. Aquaya; REACH, September 2020. This study describes and assesses the formal and informal systems used by institutions with regulatory requirements for testing drinking water quality in six sub-Saharan African countries to organize, analyze, and transmit information about drinking water quality.
Including Water Quality Monitoring in Rural Water Services: Why Safe Water Requires Challenging the Quantity Versus Quality Dichotomy. NPJ Clean Water, April 2020. Using dilemma analysis and drawing on an institutional experiment engaging 76 stakeholders, the authors conclude that conceptualizing water quality versus quantity as a dichotomy delays progress on safe water.
A Primer on Emerging Field-Deployable Synthetic Biology Tools for Global Water Quality Monitoring. NPJ Clean Water, April 2020. The authors describe current water quality monitoring strategies enabled by synthetic biology and compare them to previous approaches used to detect three priority water contaminants.
Success Factors for Citizen Science Projects in Water Quality Monitoring. Science of The Total Environment, August 2020. Three sets of factors for successful citizen science projects in water quality monitoring are discussed.
Shallow Aquifer Monitoring Using Handpump Vibration Data. Journal of Hydrology, August 2020. Researchers present a novel technology for monitoring changes in aquifer depth using handpump vibration data.
Are Presence/Absence Microbial Tests Appropriate for Monitoring Large Urban Water Supplies in Sub-Saharan Africa? Water, March 2019. This study compares 1,048 water quality test results for samples collected from five African urban water systems.
COVID-19 and Water Quality
Drinking Water Pollutants May Affect the Immune System: Concerns Regarding COVID-19 Health Effects. Environmental Science and Pollution Research, November 2020. This article discusses major contaminants in drinking water known to be immunotoxic and explores the known mechanisms of action that could likely compromise the effective immune response of humans.
Responding to Water Stagnation in Buildings with Reduced or No Water Use. American Water Works Association, November 2020. The purpose of this document is to help building managers without a water management program or without a program that addresses building water system stagnation assess and react to the problem.
Information on Maintaining or Restoring Water Quality in Buildings with Low or No Use. EPA, July 2020. The U.S. EPA recommends that building owners and managers take proactive steps to protect public health by minimizing water stagnation during closures and taking action to address building water quality prior to reopening.
Pollution – Chemical Pollution
Chemical Contamination of Drinking Water in Resource-Constrained Settings: Global Prevalence and Piloted Mitigation Strategies. Annual Review of Environment and Resources, October 2020. Chemical contamination of drinking water puts more than 1 billion people at risk of adverse health effects globally. This review focuses on arsenic, fluoride, nitrates, lead, chromium, total dissolved solids, emerging organic contaminants, and, to a lesser extent, manganese, cadmium, selenium, and uranium.
Emerging Contaminants Affect the Microbiome of Water Systems—Strategies for their Mitigation. NPJ Clean Water, September 2020. Emerging contaminants (ECs) in the environment have been consistently recognized as a worldwide concern. ECs may be defined as chemicals or materials found in the environment at trace concentrations with potential, perceived, or real risk to the “One Health” trilogy (environment, human, and animal health).
Underrepresented Groups in WaSH: The Overlooked Role of Chemical Toxicants in Water and Health. Journal of Water, Sanitation and Hygiene for Development, October 2019. The review concludes that a rapid, major effort to address toxic chemicals in WASH is necessary to meet UN Sustainable Development Goals for universal access.
Chemical Hazards in Drinking-Water. WHO, December 2020. New or revised background documents for selected chemical hazards in drinking water are now available. These documents will inform the development of the WHO guidelines for drinking-water quality. Chemicals evaluated are: anatoxin-a and analogues, bentazone, chromium, cylindrospermopsins, iodine, microcystins, organotins, saxitoxins, tetrachloroethene, and trichloroethene. Updated background documents on asbestos, manganese, and silver are also available.
The Role of Chemical Exposures in Reducing the Effectiveness of Water–Sanitation–Hygiene Interventions in Bangladesh, Kenya, and Zimbabwe. WIREs Water, August 2020. Mitigating exposures to organic and inorganic chemical immunotoxins through drinking water and other routes is likely to be a necessary‐but‐insufficient criterion for the sustainable success of WASH interventions.
Pollution – Microbial Contamination
Sanitary Inspection, Microbial Water Quality Analysis, and Water Safety in Handpumps in Rural Sub-Saharan Africa. NPJ Clean Water, January 2021. Authors discuss the relationship between sanitary inspection and water quality analysis using data from 1,028 boreholes with handpumps in 12 countries in sub-Saharan Africa.
The Utility of Escherichia coli as a Contamination Indicator for Rural Drinking Water: Evidence from Whole Genome Sequencing. PLoS One, January 2021. Researchers discuss the difficulty of interpreting health risk from E. coli grab samples, especially at household level, and how the findings support the use of E. coli risk categories and encourage monitoring that accounts for sanitary conditions and temporal variability.
Sources of Microbiological Contamination in Sachet Water from Ghana. Journal of Water, Sanitation and Hygiene for Development, February 2020. This study to assess the microbiological quality of sachet water in 21 different brands indicates an urgent need for increased regulation and standardized manufacturing to ensure safer drinking water.
Microbial Indicators of Fecal Pollution: Recent Progress and Challenges in Assessing Water Quality. Water and Health, June 2020. Research has advanced although challenges remain for the effective use of both traditional and alternative fecal indicators for risk characterization, source attribution and apportionment, and impact evaluation.
Water Treatment – Biochar
Production of Granular Activated Carbon by Thermal Air Oxidation of Biomass Charcoal/Biochar for Water Treatment in Rural Communities: A Mechanistic Investigation. Chemical Engineering Journal Advances, December 2020. This simple, innovative granular activated carbon production approach is suitable for use in small community- and household-scale applications.
High Temperature Co-Pyrolysis Thermal Air Activation Enhances Biochar Adsorption of Herbicides from Surface Water. Environmental Engineering Science, June 2019. Recent interest has arisen in the use of biochar as a low-cost adsorbent for control of organic micropollutants in water.
Ash Pretreatment of Pine and Biosolids Produces Biochars with Enhanced Capacity for Organic Micropollutant Removal from Surface Water, Wastewater, and Stormwater. Environmental Science: Water Research & Technology, March 2020. Ash pretreatment of biochar increased organic micropollutant sorption and is applicable in low-cost water treatment scenarios, such as stormwater and wastewater treatment, as well as in low- and middle-income countries.
Water Treatment – Household Water Treatment
Results of Round II of the WHO Household Water Treatment Evaluation Scheme. WHO, July 2019. This report summarizes the results of 19 out of 20 household water treatment products evaluated. These represent a range of treatment methods, including chemical, solar and ultraviolet disinfection, and ceramic and membrane filtration.
Design, Performance, and Demand for a Novel In-Line Chlorine Doser to Increase Safe Water Access. NPJ Clean Water, January 2021. The technical performance of the Venturi in-line chlorine doser and effective demand from kiosks indicate high potential for the Venturi to increase safe water access in low-income communities.
Potential of Ceramic and Biosand Water Filters as Low-Cost Point-of-Use Water Treatment Options for Household Use in Nigeria. Journal of Water, Sanitation and Hygiene for Development, January 2021. The market research indicates low popularity of the water filters due to lack of promotion and marketing. However, the research outcomes show great potential for sustainability and marketability of clay and biosand water filters.
A Hierarchical Bayesian Belief Network Model of Household Water Treatment Behaviour in a Suburban Area: A Case Study of Palu—Indonesia. PLoS One, November 2020. The socio-economic characteristics and psychological determinants of household water treatment behavior in a suburban area of Indonesia were investigated.
Zeolite Cotton in Tube: A Simple Robust Household Water Treatment Filter for Heavy Metal Removal. Scientific Reports, May 2020. Researchers report on a simple flow-through filter made by zeolite-cotton packing in a tube as a low-cost household water treatment device to remove heavy metal ions from contaminated water.
A Cluster Randomized Trial of the Impact of Education through Listening (a Novel Behavior Change Technique) on Household Water Treatment with Chlorine in Vihiga District, Kenya, 2010–2011. American Journal of Tropical Medicine and Hygiene, January 2021. Observations from this study exemplify the complexities of habits, practices, attitudes, and external factors that can create challenging conditions for implementing behavioral interventions.
Field Investigation and Economic Benefit of a Novel Method of Silver Application to Ceramic Water Filters for Point-Of-Use Water Treatment in Low-Income Settings. Water, January 2021. This study reports on field testing of ceramic water filters fabricated using a new method of silver application (using silver nitrate as a raw material) compared to conventionally manufactured filters (fabricated with silver nanoparticles).