Water stress is mounting as the world’s water demand is projected to rise 40% by 2030, while 2 billion people still rely on unimproved drinking water sources and 3 billion lack sanitation. Behind those gaps are sharp, measurable pressures on health, ecosystems, and costs, from the 24% average drop in diarrheal disease from better water quality to wastewater treatment market growth that is set to reach hundreds of billions.
Key Takeaways
- In 2020, around 2 billion people used unimproved drinking water sources and 3 billion lacked sanitation facilities
- The cost of desalinated seawater RO is commonly in the range of $0.50-$2.00 per m3 depending on energy and policy (IEA water-energy report citing typical ranges)
- In 2022, private sector participation in water and wastewater projects totaled $11.4 billion in investment commitments (OECD PPI data reported for sector)
- NRW reduction programs can cut water losses by 10-20 percentage points in pilot utilities over 2-5 years (World Bank NRW guidance ranges)
- In 2022, 17% of the global rural population used safely managed sanitation services (World Bank global water brief)
- In 2019, global wastewater treatment capacity reached about 80% in OECD countries, compared with much lower rates in low-income settings (OECD/UN-WWAP comparative indicator)
- 58% of diarrheal deaths are estimated to be due to unsafe water, sanitation and hygiene
- Waterborne diseases account for an estimated 1.7 billion cases of diarrhea each year
- At least 5.2 million deaths per year are attributed to air pollution; however, household air pollution is linked to water and sanitation-related exposures, and improved WASH interventions reduce these risks (used as linkage statistic in WASH benefit analyses)
- The global water and wastewater treatment market is projected to reach $572.5 billion by 2027 (2020-2027 CAGR reported by the source)
- The global desalination market is projected to reach $15.5 billion by 2029 (forecast base year stated by the source)
- The global water treatment chemicals market size was $25.9 billion in 2023 (reported by the source)
- The global water meter market was valued at $12.7 billion in 2023 and is forecast to reach $19.9 billion by 2030
- The global ultraviolet (UV) disinfection equipment market is expected to reach $1.9 billion by 2030
- By 2023, 61% of global wastewater treatment plants in OECD countries used activated sludge processes (reported process mix in sectoral report)
Unsafe water and sanitation still drive massive diarrhea and deaths while WASH and treatment investments are scaling up.
Related reading
01 · Category
Global Access1 stats
01
In 2020, around 2 billion people used unimproved drinking water sources and 3 billion lacked sanitation facilities
Interpretation
Global Access Interpretation
In 2020, about 2 billion people relied on unimproved drinking water sources while 3 billion lacked sanitation facilities, showing that global access to safe water and basic sanitation remains a critical, uneven challenge.
02 · Category
Cost Analysis4 stats
01
The cost of desalinated seawater RO is commonly in the range of $0.50-$2.00 per m3 depending on energy and policy (IEA water-energy report citing typical ranges)
02
In 2022, private sector participation in water and wastewater projects totaled $11.4 billion in investment commitments (OECD PPI data reported for sector)
03
NRW reduction programs can cut water losses by 10-20 percentage points in pilot utilities over 2-5 years (World Bank NRW guidance ranges)
04
The global average cost of wastewater treatment in OECD countries is about €0.70 per m3 (OECD wastewater treatment economics indicator)
Interpretation
Cost Analysis Interpretation
From a cost analysis perspective, water and wastewater spending benefits from clear efficiency gains and economies of scale, with desalinated seawater RO typically costing $0.50 to $2.00 per m3, OECD wastewater treatment averaging about €0.70 per m3, and NRW reduction programs cutting losses by 10 to 20 percentage points within 2 to 5 years, while private investment commitments reached $11.4 billion in 2022.
03 · Category
Access & Coverage2 stats
01
In 2022, 17% of the global rural population used safely managed sanitation services (World Bank global water brief)
02
In 2019, global wastewater treatment capacity reached about 80% in OECD countries, compared with much lower rates in low-income settings (OECD/UN-WWAP comparative indicator)
Interpretation
Access & Coverage Interpretation
In the Access and Coverage area, only 17% of the global rural population had safely managed sanitation services in 2022, while even by 2019 wastewater treatment capacity in OECD countries stood around 80%, showing a stark gap between well-served and low-income areas.
04 · Category
Health & Environment7 stats
01
58% of diarrheal deaths are estimated to be due to unsafe water, sanitation and hygiene
02
Waterborne diseases account for an estimated 1.7 billion cases of diarrhea each year
03
At least 5.2 million deaths per year are attributed to air pollution; however, household air pollution is linked to water and sanitation-related exposures, and improved WASH interventions reduce these risks (used as linkage statistic in WASH benefit analyses)
04
Globally, 80% of wastewater is discharged into the environment without adequate treatment, contributing to eutrophication and ecosystem degradation
05
Globally, 1.3 billion people depend on drinking water sources that are affected by fecal contamination
06
By 2030, the global demand for water is projected to increase by 40% compared with current levels
07
In 2021, about 4.0% of global public health spending was estimated to be linked to WASH interventions in cost-effectiveness analyses (Lancet/WHO-linked WASH benefit-cost studies)
Interpretation
Health & Environment Interpretation
From a Health and Environment perspective, contamination and weak wastewater management are driving huge water-related health burdens, with 58% of diarrheal deaths tied to unsafe water, sanitation and hygiene and 1.3 billion people relying on drinking sources affected by fecal contamination while 80% of wastewater is discharged without adequate treatment.
05 · Category
Market Size9 stats
01
The global water and wastewater treatment market is projected to reach $572.5 billion by 2027 (2020-2027 CAGR reported by the source)
02
The global desalination market is projected to reach $15.5 billion by 2029 (forecast base year stated by the source)
03
The global water treatment chemicals market size was $25.9 billion in 2023 (reported by the source)
04
The global smart water management market is expected to grow from $12.3 billion in 2023 to $25.9 billion by 2030
05
The global industrial water and wastewater services market was valued at $268.0 billion in 2022 (as estimated by the source)
06
The global water utility management software market is expected to reach $3.6 billion by 2030
07
US municipal wastewater treatment spending was about $113 billion in 2017 (US EPA estimate)
08
US municipal water supply spending was about $100 billion in 2017 (US EPA estimate)
09
The global non-revenue water (NRW) management market is projected to reach $6.6 billion by 2030
Interpretation
Market Size Interpretation
For the Market Size angle, the data point to a steadily expanding water sector, with the global water and wastewater treatment market projected to reach $572.5 billion by 2027 and smart water management nearly doubling from $12.3 billion in 2023 to $25.9 billion by 2030.
06 · Category
Industry Trends6 stats
01
The global water meter market was valued at $12.7 billion in 2023 and is forecast to reach $19.9 billion by 2030
02
The global ultraviolet (UV) disinfection equipment market is expected to reach $1.9 billion by 2030
03
By 2023, 61% of global wastewater treatment plants in OECD countries used activated sludge processes (reported process mix in sectoral report)
04
In 2020, the value of global water and wastewater projects funded through project finance reached $33.7 billion (OECD private participation dataset)
05
Global greenhouse gas emissions from water and wastewater services were estimated at 520-1,000 MtCO2e per year (IPCC/IEA-aligned estimate range used in water sector decarbonization studies)
06
Reverse osmosis desalination typically produces permeate with salinity reduction to about 99% for seawater (engineering guidance value)
Interpretation
Industry Trends Interpretation
Driven by growing infrastructure needs, the water industry is scaling proven technologies and financing, with the water meter market set to grow from $12.7 billion in 2023 to $19.9 billion by 2030 and global project finance for water and wastewater reaching $33.7 billion in 2020.
More related reading
07 · Category
Water Stress & Risk4 stats
01
In 2016, the global water withdrawals were about 4.6 trillion m3 per year (FAO AQUASTAT global freshwater withdrawal estimate)
02
In 2018, global municipal water withdrawals were about 1,060 km3 (UNESCO/WWAP global water use estimates cited in report)
03
In 2019, global water use increased compared with 2010, with freshwater withdrawals rising by around 1% per year (WWDR 2020 synthesis)
04
Globally, 70% of industrial freshwater withdrawals are used for cooling in power generation and heavy industry (OECD water withdrawals analysis)
Interpretation
Water Stress & Risk Interpretation
With global freshwater withdrawals still climbing by about 1% per year since 2010 and reaching around 4.6 trillion m3 in 2016, water stress is tightening as 70% of industrial withdrawals go to cooling, leaving less freshwater buffer for growing demands.
08 · Category
Resource Stress2 stats
01
70% of global freshwater withdrawals are for agriculture (commonly reported global sectoral allocation for withdrawals)
02
3.2 billion people face at least moderate water scarcity for at least one month each year (water scarcity exposure estimate)
Interpretation
Resource Stress Interpretation
Under the Resource Stress lens, agriculture accounts for 70% of global freshwater withdrawals, while 3.2 billion people experience at least moderate water scarcity for at least one month each year, showing how heavy demand amplifies widespread, recurring strain on water supplies.
09 · Category
Health Impact8 stats
01
A 2020 meta-analysis estimated that improving water quality reduces diarrheal disease by about 24% on average
02
A Cochrane review found that household water treatment and safe storage can reduce diarrhoea episodes among children by 39%
03
A randomized trial reported that chlorination reduced diarrhoea incidence by 16% compared with controls (study-specific effectiveness estimate)
04
Globally, about 700 million people lacked safely managed drinking water services in 2020 according to a JMP estimate for earlier baseline (a dataset-derived gap)
05
A systematic review reported that sanitation interventions reduced diarrhoea incidence by 7% overall (pooled effectiveness estimate)
06
A meta-analysis found that handwashing with soap reduces diarrhoeal disease by about 30%
07
A study on fecal sludge management reported that safely managed fecal sludge treatment can reduce pathogen loads by orders of magnitude (reported log-reduction figures)
08
A 2015 Lancet paper (commonly used in WASH burden-of-disease modeling) estimated that improving WASH could avert about 272,000 deaths annually (modeled impact estimate)
Interpretation
Health Impact Interpretation
From the Health Impact perspective, the evidence consistently shows substantial disease reductions when water and related WASH measures are improved, with diarrhoea cutting effects ranging from about 16% to 39% for water interventions and even larger broader benefits such as roughly 30% fewer diarrhoeal cases from handwashing with soap and an estimated 272,000 deaths avertable each year.
10 · Category
Treatment Economics6 stats
01
Energy use per unit of desalinated water depends on intake and plant design; a modern RO desalination plant often requires roughly 3–4 kWh per m3 for seawater desalination (typical published range)
02
Globally, wastewater treatment requires about 1–2% of total electricity demand (reported share of electricity used by water and wastewater sectors)
03
Municipal water supply systems in the US use about 34 billion kWh of electricity annually for treatment and pumping (US public utility energy footprint estimate)
04
US drinking-water treatment often achieves pathogen reductions required by regulations; typical conventional treatment trains remove 99%+ of Giardia and 99.9%+ of virus in performance summaries (reported filtration/disinfection log credit figures)
05
China’s wastewater treatment capacity increased from 11.8 million m3/day in 2010 to 189.5 million m3/day in 2020 (reported capacity growth in industry data)
06
The median capital cost for constructing advanced wastewater treatment (tertiary/nutrient removal) plants can exceed $1,000per m3/day of capacity (reported cost range in infrastructure cost benchmarks)
Interpretation
Treatment Economics Interpretation
From an economics perspective, water treatment is energy-light at the global scale yet capital-heavy in expansion, since desalination typically costs about 3 to 4 kWh per m3 and worldwide wastewater uses only 1 to 2 percent of electricity, while building advanced wastewater capacity in places like China has surged from 11.8 million m3 per day to 189.5 million m3 per day and can cost over $1,000 per m3 per day.
11 · Category
Infrastructure Investment1 stats
01
In 2021, the OECD reported that official development assistance (ODA) for water supply and sanitation totaled about $8.5 billion (commitments estimate)
Interpretation
Infrastructure Investment Interpretation
In 2021, OECD reported $8.5 billion in ODA commitments for water supply and sanitation, underscoring that infrastructure investment in water is receiving substantial, measurable international funding.
Reference
Cite This Report
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APA
Kevin O'Brien. (2026, February 13). Water Statistics. Gitnux. https://gitnux.org/water-statistics
MLA
Kevin O'Brien. "Water Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/water-statistics.
Chicago
Kevin O'Brien. 2026. "Water Statistics." Gitnux. https://gitnux.org/water-statistics.
Sources & references
50 datasets cited across this report · attribution is report-level
+19 additional datasets cited (not shown individually)