Research & evidence
Most water crises are governance crises before they are engineering crises. This page brings together the key numbers, frameworks and regulatory deadlines behind our tools. Each item ends with a "so what" for boards and civic groups, and every figure links to its source.
Key numbers
Framework
The OECD groups good water governance into three mutually reinforcing dimensions. Effectiveness means clear goals and the right actors at the right scale. Efficiency means getting the most value from data, money and rules. Trust and engagement means integrity, inclusion and fairness. Our tools map onto all twelve.
| # | Principle | Dimension | Question a board can ask | Our tool |
|---|---|---|---|---|
| 1 | Clear roles & responsibilities | Effectiveness | Who sets policy, regulates, operates, pays — on one page? | Self-check |
| 2 | Appropriate scales within basin systems | Effectiveness | Do we co-ordinate with everyone who shares our sources? | Assessment |
| 3 | Policy coherence | Effectiveness | Do land-use, energy and farm policies help or hurt water? | Assessment |
| 4 | Capacity | Effectiveness | Do we have the skills to manage assets and contracts? | Assessment |
| 5 | Data & information | Efficiency | Is there a published annual water balance? | NRW & ILI |
| 6 | Financing | Efficiency | Is revenue ring-fenced and renewal funded? | Budget questions |
| 7 | Regulatory frameworks | Efficiency | Who independently checks tariffs and performance? | Agenda |
| 8 | Innovative governance | Efficiency | What did we pilot, and was it evaluated? | Assessment |
| 9 | Integrity & transparency | Trust & engagement | Are contract awards and variations public? | Red flags |
| 10 | Stakeholder engagement | Trust & engagement | Did users see the options before the decision? | Agenda |
| 11 | Trade-offs across users, areas & generations | Trust & engagement | Can low-income households pay? Who's served first? | Affordability |
| 12 | Monitoring & evaluation | Trust & engagement | Are decisions logged and reviewed? | Decision log |
Limiting waste
The International Water Association's standard balance splits system input into billed and unbilled authorised use, apparent losses (meter error, billing errors, theft) and real losses (leaks, bursts, tank overflows). Apparent losses cost revenue; real losses cost water, energy and chemicals.
So what: ask for the four-way split, not one "loss %".
NRW as a percentage falls when consumption rises and rises when people save water, even if no pipe has changed. It also penalises systems with low per-capita use.
So what: track real losses in litres per connection per day, or m³ per km of mains per day.
ILI = current annual real losses ÷ unavoidable annual real losses (UARL). The standard UARL formula is (18 × km mains + 0.8 × connections + 25 × km private service pipe) × average pressure in metres, in litres/day. An ILI of 1.0 is the technical minimum.
So what: the calculator now computes ILI and the World Bank Institute band.
Liemberger & Wyatt estimate that reducing global NRW by one third would save around US$13 billion a year. They put realistic payback at about 7–10 years.
So what: loss reduction belongs in the capital plan, not only the maintenance budget.
Under the recast Drinking Water Directive (Art. 4(3)), Member States had to assess leakage, using ILI or another suitable method, for large suppliers (≥10,000 m³/day or ≥50,000 people) and report by 12 January 2026. The Commission must set an EU leakage threshold by 12 January 2028. Countries above it will need action plans.
So what: EU utilities should have an ILI figure now. Ask to see it.
Leak flow rises with pressure, and so does burst frequency. That's why the UARL formula scales with pressure. Pressure management by district metered area (DMA) is often the fastest, cheapest way to cut real losses.
So what: ask what share of the network is in DMAs with managed pressure.
Integrity & trust
The Water Integrity Network's 2016 outlook argues that every 10% of investment lost to corruption costs over US$75 billion a year worldwide. It cites a 2015 audit of a Benin water programme that found €4 million unaccounted for out of €70 million.
So what: screen tenders and contract variations with the 16 red flags.
Illegal connections, bribes to skip disconnection and manipulated meter readings show up as apparent losses. Phnom Penh's turnaround began by tackling these directly.
So what: a large apparent-loss share is an integrity signal, not only a technical one.
In Flint, Michigan, state-appointed emergency managers took over local decision-making. The 2014 source switch went ahead without corrosion control, and the city council's 2015 vote to switch back was non-binding.
So what: protect public oversight, especially under fiscal stress. See the case study.
After a 2017 television investigation alleged water theft in Australia's Barwon–Darling, New South Wales moved enforcement to a new independent regulator, operating from April 2018.
So what: the body that promotes water use shouldn't be the only one that polices it. See the Murray–Darling case.
Budgets & assets
Austria's Court of Audit found about 0.3% of the drinking-water network renewed per year, against roughly 2% needed to preserve its value. EurEau's 2025 statistics name renewal as the top concern of Europe's water services.
So what: ask for the renewal rate as a share of the network, and compare it with the expected service life. Use the renewal gap calculator.
A World Bank study estimated capital needs of about US$114 billion a year to reach universal safely managed water and sanitation (SDG 6.1 and 6.2), roughly three times recent investment. Operating and maintenance costs come on top.
So what: new connections without funded maintenance create tomorrow's failures.
The OECD's "3Ts" framework says services are paid for by some mix of user tariffs, public budgets and transfers such as grants. Problems start when nobody decides the mix openly.
So what: ask which of the three pays for renewal, and whether that is written down.
In Jackson, Mississippi, a failed metering and billing contract cut revenue for years before the 2022 treatment-plant crisis left more than 150,000 people without safe water.
So what: treat billing systems as critical infrastructure. See the Jackson case.
Sanitation & wastewater
In 2024, 3.4 billion people lacked safely managed sanitation and 1.7 billion lacked basic hygiene at home, according to the WHO/UNICEF Joint Monitoring Programme.
So what: sanitation plans need the same governance attention as drinking water.
England's near-complete monitoring of storm overflows showed 450,398 spills lasting 3.61 million hours in 2024, and helped trigger a review that recommended replacing the economic regulator.
So what: publish spill data for every overflow. See the England case.
The recast Urban Wastewater Treatment Directive (2024/3019) extends treatment to towns of 1,000 p.e., adds micropollutant removal for large plants by 2045, and makes pharmaceutical and cosmetics producers pay at least 80% of that extra cost.
So what: transposition is due by 31 July 2027; start the gap analysis now. See the obligations table.
Scarcity & basins
Cape Town said most taps would be turned off if its major dams fell to 13.5%. Regularly updated "Day Zero" forecasts, restrictions and pressure management helped cut daily use by more than half between 2015 and 2018.
So what: agree trigger levels and a public forecast before a drought. Try the drought runway calculator.
OECD principle 2 asks for decisions at the scale of the catchment or aquifer. The EU Water Framework Directive (2000) requires river basin management plans for the same reason.
So what: know who else draws on your sources, and what you have agreed with them.
Australia's Murray–Darling Basin Plan (2012) set sustainable limits on extraction and a baseline target to recover 2,750 GL a year for the environment. Its legitimacy has depended on metering and enforcement.
So what: no allocation rule is fair if extraction isn't measured.
The Dutch water boards, the oldest founded in the 13th century, are elected every four years and levy their own taxes for flood protection, water levels and wastewater treatment.
So what: long-term water tasks need protected revenue and visible oversight. See the case.
Standards timeline
IWA standard water balance and performance indicators published, the basis for comparing water losses internationally.
UN General Comment No. 15: water must be sufficient, safe, acceptable, physically accessible and affordable.
UN General Assembly resolution 64/292 recognises the human right to safe drinking water and sanitation.
OECD Principles on Water Governance and SDG 6 (clean water and sanitation for all by 2030) adopted.
OECD Council Recommendation on Water integrates the governance principles. Water Integrity Network publishes its first Global Outlook.
Recast EU Drinking Water Directive (2020/2184) adds risk-based safety planning, leakage assessment and access-to-water duties.
Recast EU Urban Wastewater Treatment Directive (2024/3019) adds energy neutrality goals and extended producer responsibility for micropollutant removal.
July: England's Independent Water Commission makes 88 recommendations; the UK government announces Ofwat will be abolished.
12 January: EU Member States' leakage assessments due to the Commission. 20 January: UK White Paper A New Vision for Water sets out a single new water regulator for England.
31 July: Member States must transpose the recast Urban Wastewater Treatment Directive into national law.
By 12 January: Commission to set an EU leakage threshold by delegated act. Countries above it will need action plans.
SDG 6 deadline. On current trends, universal safely managed drinking water and sanitation will not be reached.
Integrated urban wastewater management plans due for EU agglomerations above 100,000 p.e.
Quaternary treatment for large EU plants (150,000 p.e. and above) and energy neutrality for plants of 10,000 p.e. and above.
Sources