Clean Water & Sanitation
2.2 billion people lack access to safely managed drinking water, and 3.5 billion lack safe sanitation. Contaminated water and poor sanitation cause 1.4 million preventable deaths annually, primarily from diarrheal disease in young children.
Scale of the Problem
Every $1 invested in water and sanitation infrastructure yields $4–$12 in economic returns, per WHO.
703 million people lack basic water services; 1.7 billion lack basic sanitation; 2.3 billion lack basic handwashing facilities. Sub-Saharan Africa has the highest rates of unimproved access, while South Asia carries the largest absolute numbers without sanitation. WASH-related diseases cause 1.4 million deaths annually. Beyond mortality, waterborne illness produces enormous disability: diarrhea hospitalizations, stunting from repeated intestinal infections in children, and school absenteeism that impairs learning.
Why This Is Pressing
2.2 billion people lack access to safely managed drinking water, and diarrheal disease — 88% of which is attributable to inadequate WASH — kills 1.4 million people annually, 90% of them children under five. This is a solvable problem: water purification interventions like chlorination cost as little as $1–$2 per person per year, making WASH among the most cost-effective development investments available. Evidence Action's dispensers-for-safe-water program is rated by GiveWell as a top charity. Yet the global WASH financing gap is $54 billion per year, and the Sustainable Development Goal to achieve universal clean water by 2030 is badly off-track. The case for dramatically scaling WASH investment is clear, evidence-backed, and undeniably urgent.
Why It's Neglected
Global WASH funding is approximately $60 billion per year — roughly half the estimated requirement. Most funding comes from governments with weak accountability for access outcomes. Philanthropic WASH funding with rigorous measurement is a small fraction of this. The most cost-effective urban water access interventions — chlorination dispensers at community water points — receive under $50 million globally per year despite achieving verified impact at under $2 per person protected.
Can It Be Solved?
WASH is highly tractable. Chlorination of water reduces diarrhea incidence by 25–40% in field conditions. Evidence Action's safe water program delivers this at approximately $1–2 per person per year, with GiveWell rating it among the top 10 most cost-effective charities globally. Community-Led Total Sanitation programs have achieved open-defecation-free status in thousands of villages across Africa and Asia. School WASH improvements simultaneously deliver health, attendance, and gender equity benefits. The primary constraint is funding, not technical knowledge.
Research & Solutions
Safe Water for All: The Case for Prioritizing WASH Interventions
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What You Can Do
What this problem still needs
Donate to Evidence Action's dispensers-for-safe-water program, rated among GiveWell's top charities for cost-effectiveness. Support Water.org for financial access approaches to household water infrastructure. Advocate for SDG 6 financing in development aid budgets. Career opportunities in WASH engineering, public health, and development policy at UNICEF, WHO, or implementing NGOs.
Priority Score
22
Breakdown
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