How Sanitation Impacts Health and the Environment: An In-Depth Look

Sanitation is far more than just toilets and clean streets. It is a foundational pillar of public health, shaping how diseases spread, how rivers flow, and how soil sustains crops. When sanitation systems break down, the ripple effects touch nearly every part of life, from a child’s growth in a village to the quality of water that reaches a city tap. Understanding these connections helps explain why sanitation continues to be one of the most studied determinants of population health and environmental wellbeing.

Sanitation as a social determinant of health
Why sanitation is a question of equity
The disease burden in numbers
Environmental impacts of poor sanitation
Water pollution and contaminated rivers
Waste accumulation and soil degradation
Air, smell, and climate links
Solutions for sustainable sanitation
Waste stabilisation ponds
Community-based sanitation management
Waste recycling and circular sanitation
Policy and infrastructure together

The World Health Organization frames social determinants of health as the conditions in which people are born, live, work, and age. Sanitation sits squarely within this framework because access to a safe toilet, clean water, and proper waste disposal is rarely distributed equally. It depends on income, caste, geography, housing type, and gender. A landmark review on social determinants of health across Indian states highlighted that unimproved sanitation, child undernutrition, and indoor air pollution remain top priorities for policy because they cluster together among the poorest households.

Poor sanitation drives disease patterns in predictable ways. Faecal-oral pathogens cause diarrhoea, cholera, typhoid, hepatitis A and E, and various parasitic infections. Children under five carry the heaviest burden. The World Economic Forum has reported that lack of water, sanitation, and hygiene contributes to about 400,000 deaths each year in India, with most of these linked to diarrhoeal disease among young children. Beyond mortality, repeated infections cause environmental enteropathy, which damages the gut lining, impairs nutrient absorption, and stunts growth even when food intake is adequate.

Why sanitation is a question of equity

Sanitation gaps are not random. A 2024 analysis using National Family Health Survey data showed that socioeconomic inequality in the utilisation of improved sanitation facilities persists across Indian households, with the poorest quintiles disproportionately excluded. Researchers studying rural sanitation have also pointed out that caste-based notions of untouchability can perpetuate open defecation, since cleaning pit latrines is socially stigmatised. These layered inequalities mean that even when toilets are built, they may not be used by everyone, or maintained over time.

Gender adds another dimension. Women and adolescent girls without access to private toilets often delay using sanitation facilities, leading to urinary infections and psychosocial stress. Studies on the Swachh Bharat Mission have noted that open defecation disproportionately affects women, increasing risks of harassment and assault, particularly at night.

The disease burden in numbers

The link between sanitation and mortality is well documented. According to a review on water as a social determinant of health, between 1.5 and 2 million children worldwide die each year from illnesses connected to water and sanitation. In India, the cost of treating preventable waterborne disease places a heavy strain on already stretched primary health systems. The health costs linked to water pollution alone are estimated at 470 to 610 billion rupees per year, much of it associated with diarrhoeal mortality and morbidity in young children. These are not abstract figures. They translate into lost school days, lost wages, and households pushed deeper into poverty.

Environmental impacts of poor sanitation

When sanitation systems fail, the environment absorbs the cost. Untreated sewage, faecal sludge, and solid waste rarely disappear quietly. They flow into rivers, seep into groundwater, accumulate on land, and alter the chemistry of soil. The result is a slow-moving environmental crisis that compounds the health burden already discussed.

Water pollution and contaminated rivers

The Ganga remains one of the most cited examples of how sanitation failures translate into ecological damage. The Central Pollution Control Board has long observed that organic matter and bacteria of faecal origin continue to dominate the water pollution problem in India, with biological oxygen demand rising in many major rivers. Even well-intentioned interventions can backfire when downstream infrastructure is missing. A recent study on the unintended consequences of sanitation investment found that scaling up latrine construction without adequate faecal sludge treatment increased fecal contamination of rivers by 72 percent in some areas, partially offsetting the health gains of reduced open defecation.

Groundwater is similarly vulnerable. Pit latrines placed too close to wells or in sandy soils allow pathogens and nitrates to leach into aquifers. Since a large share of rural Indian households still depend on hand pumps and borewells for drinking water, this contamination directly shapes the disease load in communities where toilets were supposed to bring improvement.

Waste accumulation and soil degradation

Solid waste tells a parallel story. India generates roughly 62 million tonnes of waste per year, of which only about 80 percent is collected, and far less is properly processed. The uncollected portion ends up in drains, vacant plots, and water bodies. Sewage treatment plants are often non-functional due to poor design, irregular electricity, or absentee staff, so wastewater percolates into the soil or evaporates without treatment.

Over time, this changes soil chemistry. Heavy metals from industrial effluents, pathogens from untreated sewage, and persistent organic compounds reduce soil fertility and crop productivity. Polluted irrigation water leads to soil degradation and loss of arable land, while contaminated crops carry health risks back to consumers. In urban slums where waste management is weakest, waste is often dumped directly into nearby water bodies, harming aquatic biodiversity and damaging the livelihoods of communities that depend on fishing and small-scale farming.

Air, smell, and climate links

Decomposing waste releases methane and other greenhouse gases, linking sanitation failures to the broader climate question. Open dumps and poorly managed septic tanks also generate odours, attract vectors like flies and rodents, and create breeding sites for mosquitoes. The combined effect is a degraded living environment that suppresses property values, discourages investment, and reinforces the very poverty cycles that produced the sanitation gap in the first place.

Solutions for sustainable sanitation

Recognising the scale of the problem, researchers and policymakers have moved toward sanitation models that treat waste as a resource rather than a nuisance. Three approaches stand out: waste stabilisation ponds, community-based management, and waste recycling.

Waste stabilisation ponds

Waste stabilisation ponds are large, shallow, human-made basins that treat wastewater using sunlight, wind, algae, and microorganisms rather than electricity or chemicals. The three main types are anaerobic, facultative, and maturation ponds, often arranged in series so that wastewater becomes progressively cleaner as it moves through the system. Anaerobic ponds break down heavy organic loads, facultative ponds rely on algae to produce oxygen for bacteria, and maturation ponds polish the effluent and remove pathogens.

Their appeal in resource-constrained settings is practical. A technical review on waste stabilisation ponds for wastewater treatment notes that they achieve higher pollutant removal at lower cost than many conventional systems, generate fewer greenhouse gas emissions, and require relatively simple operation and maintenance. The treated effluent retains nitrogen and phosphorus, making it useful for agricultural reuse. The famous wastewater-fed fishponds of Kolkata, where municipal sewage supports a productive aquaculture system, are an internationally cited example of how this technology can work at scale.

Community-based sanitation management

Infrastructure alone rarely solves sanitation problems. Toilets built without community ownership often go unused or fall into disrepair. Community-based sanitation management shifts decision-making to local users, who help plan, finance, operate, and monitor facilities. This is particularly important in peri-urban areas where land ownership is uncertain and household toilets are not feasible. An exploratory study from Jharkhand found that clean and safe shared sanitation facilities played a meaningful role in equalising access for the poorest households, and were used even by people who had a private toilet at home.

Behavioural change communication is the other half of this approach. The Swachh Bharat Mission combined toilet subsidies with intensive awareness campaigns, and evaluations have shown that the programme reduced open defecation meaningfully when behavioural messaging accompanied infrastructure provision. Sustained use, however, requires continued investment in maintenance, faecal sludge management, and education, especially as new generations of users come online.

Waste recycling and circular sanitation

The third pillar is treating waste as a resource. Recycling sanitation outputs can produce biogas for cooking and electricity, compost for agriculture, and treated water for irrigation. Decentralised wastewater treatment systems, including constructed wetlands and small-scale anaerobic digesters, allow housing societies, schools, and panchayats to manage their own waste streams and capture value from them.

This circular approach also strengthens the economic case for sanitation. When effluent is reused for irrigation, communities save on freshwater. When biogas replaces firewood, indoor air quality improves and forests are spared. When organic waste returns to fields as compost, soil health recovers and chemical fertiliser dependence falls. The Jal Jeevan Mission and related programmes increasingly emphasise these integrated approaches alongside piped water supply.

Policy and infrastructure together

None of these solutions work in isolation. A study on sanitation, socio-economy, and groundwater pollution across India found that sanitation gains translate into public health improvements only when education levels rise and hygiene practices change alongside infrastructure. Investment in sewage treatment plants must be matched with reliable electricity, skilled operators, and accountability mechanisms. The long history of sanitation programmes in India, from the National Water Supply and Sanitation Programme of 1954 to the Total Sanitation Campaign and Swachh Bharat Mission, shows that consistent political commitment and ground-level implementation matter as much as the technology chosen.

What do you think? If sanitation infrastructure and behavioural change must move together, which one tends to lag behind in your own neighbourhood, and what would it take to close that gap? And how might treating wastewater as a resource rather than waste change the way Indian cities plan for the next two decades?

References

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How Sanitation Impacts Health and the Environment: An In-Depth Look

Table of Contents

Sanitation as a social determinant of health 🔗

Why sanitation is a question of equity 🔗

The disease burden in numbers 🔗

Environmental impacts of poor sanitation 🔗

Water pollution and contaminated rivers 🔗

Waste accumulation and soil degradation 🔗

Air, smell, and climate links 🔗

Solutions for sustainable sanitation 🔗

Waste stabilisation ponds 🔗

Community-based sanitation management 🔗

Waste recycling and circular sanitation 🔗

Policy and infrastructure together 🔗