Description
1. Introduction
Use for global reporting: The collective purpose of UN-Water is to monitor the performance of the water sector from
the perspective of a sustainable development objective. UN-Water also follows a set of more specific objectives
related to specific dimensions of water management and related Millennium Development Goals (particularly Goal 7)
that also require performance assessments.
Presentation: The Task Force report 1 proposes a representation of the water sector, intrinsically linked to the
development of a given territory. It classify water indicators as ‘context indicators‘, ‘functioning indicators’ and
‘governance indicators‘. Considered jointly, these three dimensions allow the performance of the water sector to be
assessed, leading to the definition of related ‘performance indicators’.
Four categories of indicators to understand the water sector
(ref. ‘UN-Water Task Force IMR, 2009b2’)
Context Some indicators relate to the natural context (e.g. water availability, rainfall), to infrastructure (such as water
treatment capacity, or storage), or to human and economic capitals. ‘Context indicators’ are required to act as
benchmarks when assessing the achievements of another territory with a comparable context.
Functioning Functioning relates to inputs, outputs and outcomes (e.g. water use intensity). A number of indicators relate to
describing the dynamic functioning of the water sector at the national level (e.g. water withdrawals, water
depletion or wastewater actually treated).
Governance A set of governance indicators is required to track the possible explanations behind the different levels of
performance achieved between the given territory and different benchmark territories. The breadth of governance
indicators must embrace territorial water resources and water uses management to provide an insightful diagnosis
of possible weak spots in need of further investigation and possible improvement or reforms.
Performance Performance adds an element of evaluation. Performance assessment relates to considering the functioning of the
sector in relation to its objectives and within a given context. Issues of efficiency/productivity, effectiveness and
impact can be considered (e.g. access to water supply and sanitation or value added in agriculture or industry).
Level: The implicit geographical scale adopted by UN-Water is the national level, although some indicators could be
monitored at other levels as well. Indeed, other levels are necessary for more detailed assessments (regional, basins,
local) or benchmarking objectives (cities, irrigations schemes, industries).
Periodicity: The indicators should be updated regularly (1 to 5 years according to the data set).
Data: These indicators build on the databases of UN-Water members and partners, updated with information provided
by authorities from Member States or from internal UN and other international or regional sources (e.g. OECD,
Eurostat, European Environmental Agency, Blue Plan/MAP/UNEP).
These annexes (completed by an excel document) provide examples of what could be a regular snapshot of the ‘water
sector situation, context and functioning’ – provided supporting data are improved in terms of coverage and updates, as
well as elements on the existence of key governance means at global, regional and national levels. In addition, it provides
a statistical Annex, as well as a summary of existing global initiatives concerning monitoring, reporting and the
development of indicators; as well as more elements of definitions and detailed methodology sheets for the short term
indicator set.
1 UN-Water TF-IMR. 2009a. ‘Monitoring progress in the Water sector, A limited indicator set to inform on the situation : Draft
report of the Task Force 30/7/2009 .
2 UN-Water TF-IMR. 2009b. ‘Assessing the water sector’, concept paper prepared for UN-Water Task Force.
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2. A snapshot of the water sector using the UN-Water set of key
indicators
It is possible to present a snapshot of the water sector – its context, functioning and performance – using a subset of
the UN-Water key set of indicators (Ref. Report of UN-Water Task Force on Indicator, Monitoring and Reporting,
2009) and that are illustrative of certain questions received by UN-Water from information users.
Ind. Simple Definitions
1. Total resources that are offered by the average annual natural inflow and runoff that feed each hydrosystem (catchment area or
aquifer).
2. Total cumulative storage capacity of all large dams.divided by the actual average surface runoff that is produced inside the
country.
3. Percentage of the renewable water which is used (%)
4. Percentage of water use of each sector (agriculture, domestic, industry) divided by the Total water withdrawals (all uses)
5. Evolution of freshwater fish production (capture and aquaculture)
6. A country uses multiple options to provide the food consumed internally –agriculture rainfed, irrigation, food imports-. the
virtual water indicates the water volume embeeded in the food imported.
7. JMP definition of access to sanitation
8. JMP definition of access to water supply
9. Crude proxy: Value of agricultural production divided by the water volume abstracted for agriculture (does not take into account
the use of rainfall)
10. Crude proxy: Value of industrial production divided by the water volume abstracted for industry (does not take into account the
degradation of water in quality after use; and the different between industries).
11. % of people connected to public wastewater treatment plants (primary secondary. tertiary)
Issues Indicators Unit Source
Context
Population growth 1- TARWR-Renewable water resources/year m3/cap FAO-Aquastat (latest available);
(IGRAC, GRDC)
2- Storage capacity surface water/surface water
resources (and storage / cap)
%
(m3/cap)
FAO-Aquastat (latest available);
(ICOLD)
Climate change
+ internal groundwater /IRWR % FAO-Aquastat (latest available)
Functioning
Intensity of water use 3- % renewable water used (+ % renewable
groundwater used)
% FAO-Aquastat (latest available)
Diversity of water
withdrawals
4- Withdrawals per main sectors-agriculture,
domestic, industry- over Total withdrawals
% FAO-Aquastat (latest available)
On stream water
needs: fishery
5- Change in freshwater fish production
(breakdown capture & aquaculture)
tons/yr FAO-Fishstat (latest available)
Trade & water use 6- Share of blue, green, virtual water used to
produce food in a country
% UNESCO-IHE; FAO-AQUASTAT
Performance
Access to water
supply
7. % population using an improved drinking
water source
% JMP, UNESCO-WHO (2008 report;
data from 2006)
Access to sanitation 8- % population using an improved
sanitation facility
% JMP, UNESCO-WHO (2008 report;
data from 2006)
Productivity
agricultural water
9- Irrigated added value / Agricultural water use $/cap/
m3
FAO-Aquastat (latest available);
country studies; World Bank
Productivity of
industrial water
10-industrial added value / industrial water use $/cap/
m3
FAO-Aquastat (latest available);
UNIDO; World Bank
Water quality 11- Wastewater treatment connection rates % OECD, Eurostat
2.1 Population growth: water competition or water crowding?
Population growth and its development needs drive water development – direct water demands for various needs, or indirect
through migration or urbanisation. Population growth represents a main driver of pressure on the renewable but limited water
resources in a given territory.
Less than 1% of the total freshwater resources on earth (about 200 000 km3 of water) is theoretically usable by humans and
ecosystems and it is very unequally distributed. In an average year, it rains from a few millimetres (e.g. 61 mm in Egypt) to more than
10 metres, according to where we are. This diversity is amplified between climatic areas, and years – dry and wet. The ‘resources’
theoretically accessible to humans are assimilated to actual renewable freshwater resources, TARWR, defined as the average
annual flow of rivers and recharge of aquifers generated from precipitation. TARWR gives the maximum theoretical amount of water
annually available for each country in cubic kilometres. TARWR is based on a long-term period (30 years) and indicates a renewable
but finite amount of water ‘potentially available’. TARWR estimates are the basis for planning water development.
The indicator (water resources per capita) is frequently used to show the mismatch between freshwater resources – a renewable
but finite resource- and population, and a sense of the level of competition. It indicates a risk of scarcity3 when population (and its
needs) are high when compared with the water ‘availability‘ of water. A country is said to be rich in water when it has more than
1700 m3 /inhabitant/year4, while a water scarce country is below 1000 m3 (and becomes extremely water scarce when below 500
m3/inhab/year).
The reverse indicator, the ‘water crowding’ indicator (population per m3), gives a stronger image of the level of competition over
the finite resource. Countries with 600 people per million m3 of the resource are considered water scarce.
These indicators provide an estimate of the maximum theoretical amount of water resources in a country. The available water
resources will be less, according to various factors, but the indicators are an overall measure of the country’s resources. This also
provides an average annual per capita volume of water available to individuals within the country. Within the indicator are five
important dependencies, which relate to each nation’s TARWR as to how much of that water resource volume is:
• flowing from outside the country (a security & political issue)
• generated surface water runoff ( a precipitation issue)
• generated groundwater recharge (a sustainability issue)
• shared in both the groundwater and surface water regimes (a sustainability issue)
• committed to downstream nations. (a security & political issue)
These indicators can be used in scenario exercises using population projections for 2050 and considering TARWR stable. However,
climate change may change the TARWR values and change the water competition landscape, particularly in areas scarce in water and
where population growth is faster
With fast population growth, the gap increases between ‘water rich’ and ‘water scarce’ countries. People are not living where
resources are the most abundant: 364 million are water poor (living in areas with less than 1000 m3/inhab/year) and 127 million are
water stressed (in areas of less than 500 m3/inhab/year). Population growth has been faster in arid and semi-arid areas. By 2050, 1,282
million people will be living in countries or regions with absolute water scarcity, and two-thirds of the world’s population could be
under stress conditions.
Improving the indicator
Climate is changing precipitation patterns and temperatures. The impacts on natural resources are unknown but the long term
average of water resources (TARWR estimates) may need to be revised for future planning. in addition, human uses have also an
impact on water runoff and evaporation. A specific project is proposed by the WWAP EG IMD to revise these estimates.
Humans can in fact access only part of the resource. Differences in water accessibility (storing flood water, reaching water stored
1000m below the ground), variability (between dry and wet years) and quality (between freshwater to brackish or saline resources)
are increasing the gaps between rich and poor countries. Only part of the total actual renewable resources (TARWR) is in fact
‘exploitable’ – due to technical, economical, political or environmental constraints. Criteria and definitions change from country to
country, but they enable us to calculate ‘environmental flow assessments’. Calculating the total exploitable RWR per capita or its
reverse would give a darker but more objective indication. For the Mediterranean region, the Blue Plan/MAP/UNEP calculates
exploitable water resources per capita from country estimates of their ‘exploitable resources’.
3 Water scarcity is a relative concept and can occur at any level of supply and demand..
4 The criteria were defined by Malin Falkenmark on the basis of the water necessary for all uses and in particular irrigation needs.
It is more relevant for arid and semi arid context.
Measurability
The indicator is defined as the total resources that are offered by the average annual inflow and runoff that feed each hydrosystem
(catchment are or aquifer) and that is ‘available in theory’ per person. The reverse indicator gives a sense of crowding over a finite
resource. A national figure, however, can hide great differences within the country, particularly in large countries with very diverse
climates. The indicator would be most significative at the sub-regional level.
Data sets of TARWR are available for 174 countries in the AQUASTAT database. The 28 countries of the database where data are
missing are mostly small islands. The compilation of TARWR estimates was prepared in 2003 through a critical review of multiple
national and international sources for the different data items necessary to compute TARWR. The estimates are revised only if new
data sets are available.
Total actual renewable water resources (TARWR in km3/yr) is calculated in the AQUASTAT database as follows =(External
inflows + Surface water runoff + Groundwater recharge) – (Overlap +Treaty obligations).
Comment: TARWR is a fixed value (rarely updated), therefore it simply indicates a growing population pressure.
Experts (WWAP, 2009b) indicate that there is a need to revise the national estimates of TARWR, and look at:
– how hydrology data are produced at national level (measurements, estimations, monitoring networks functional)
– ‘changes in the long term as averages – 30 years’ that would account for the change in water cycle and improvement in
measurements and estimations for some of the data items using modern technologies.
Detailed global information systems are being compiled on sub-components of TARWR, in particular on groundwater resources
by the International Groundwater resources Centre (IGRAC), and on river flows by the Global runoff data centre (GRDC).
Additional elements can be found with regional organizations or thematic networks such as (UNESCO/FRIEND, & HELP).
Figure 1. Actual renewable water resources per capita (Aquastat online global map)
Calculated at the country level, resources per inhabitant ranges between a few m3 (e.g. 7.20 m3/inhab /year in Kuwait) to millions of
m3 /inhab/year. In large countries, this national indicator is hiding great internal differences. For example, in Spain, water resources
used per capita range from 500 m3/year in the south east to 6610 m3/year in the Ebro Basin.
Looking into the future and adopting the 1700 m3/cap/year limit, 644 millions people may be in excess to the water the nature
could offer!
2.2 Climate: variability and vulnerability?
Climate change is a main source of change to water cycle patterns (change in total water resources annually and moving averages if
the water cycle changes). Rains provide water for rivers, aquifers, oceans and soils – the main support for vegetation and crops.
Water stored in the soil is pumped by the plant’s roots and transpired into the atmosphere through its leaves (green water flows). But
these rains also bring a risk of destructive events. Humans have always had to adapt to natural climate variability and mitigate risks
linked to extreme events.
Climate variability influenced societies, in particular those living in arid and semi-arid areas, where rainfall periods are short and
floods can be particularly destructive. For example, West Africa witnessed a wet 1930-1960 period, followed by droughts in 1970-
1980 and better rainfalls in the years 1990 and 2000. These years have shown the vulnerability of population to climate variability,
where droughts lead to massive famine events in the Sahel areas. In addition, demands are often seasonal, relating not only to
agriculture, but also to peak demands for tourism, and hydropower production . For millennia, people have tried to control and store
water flows by creating reservoirs and storing water to regulate seasonal flows, limit floods and overcome dry spells..
Climate change adds a new dimension with anticipated changes in the precipitation regime and temperature that may affect water
availability in some areas and water use needs, and exacerbate vulnerability. Some areas are particularly at risk when dependant on
rainfed agricultural production, one of the most climate-dependant economic sectors, which plays a critical livelihood support and
safety net role in many poor rural areas of the world. Uses that depend directly on rainfalls or indirectly on the quantity of water
flowing or stored will be affected. The GIEC predicts yields from rain-dependent agriculture could be down by 50 percent by 2020.
Himalayan snow and ice, which provide vast amounts of water for agriculture in Asia, are expected to decline by 20 percent by 2030
(FAO). A typology of climate change impacts on major agricultural systems proposed by FAO (2008) pinpoints areas where major
changes are expected and where it would be necessary to monitor closely hydrological changes, adapt and mitigate.
With increasing uncertainty, it is impossible to do without some form of water storage, either surface (reservoirs or water harvesting
systems) or underground (cisterns, aquifers). The mitigation approach to climate change elevates the need for water storage – small to
large – to a higher priority, as well as the need to improve irrigation infrastructure where rural livelihoods are at stake.
The indicator proposed below focuses on ‘existing coping infrastructures compared to potential’: to store water (natural or
man-made surface reservoirs), with access to ground storage (aquifers) or with capacity to bring it where it is most needed (irrigated
areas). It gives a measure of the country’s ability to cope with water resources variability (worsened in the context of climate change).
Improving this indicator
The context information on infrastructure should be accompanied by an improved understanding of changes in the natural water
cycle. A recent study in Morocco, a water-scarce country (940 m3/inhab or 1064 people per hm3) analyzed historic data sets and
concluded that annual rainfall and runoff coefficients have changed. In most of the country, the annual runoff coefficient is lower. 5
Figure 2. Annual precipitation trends, 1900-2000 (Ref. UNEP, geo outlook 4, 2008)
In the medium term, it is anticipated that global observation and monitoring systems (e.g. WMO/WHYCOS,GRDC, IGRAC) and
programmes (WWAP) will be able to provide a more direct indicator of ‘changes in water resources variability’ based on historic
data sets of rainfall/runoff, and would assess ‘moving long-term averages (30 years) of TARWR’. Such a calculation will be based on
the global network of existing and regularly monitored meteorological and river flow stations, but would also need to find ways to
overcome data gaps (where no stations are available) using modern technologies such as remote sensing instruments (GRACE,
GOCE, satellite altimetry and other space methods) and modelling. It may stimulate the improvement of field level measurement and
5Singla Stéphanie, June 2009.
pinpoint a representative sample of rainfall stations and natural flow measurement points (selected where more critical changes are
expected, and where long historic data sets exist today and will be maintained).
Measurability
WWDR3 indicates that for terrestrial hydrologic observation systems, data is inadequate and deteriorating. Many systems lack
adequate quality insurance and control standards for calibrating instruments. Basic capacity to assess, interpret and apply water cycle
information from both terrestrial and satellite observation system is often insufficient. (chapter 13, pp 229).
Data on rainfall are gathered by the GPCC/WMO and updated every two years. Data on river flows of main rivers are gathered by the
Global runoff data centre (GRDC /managed in Koblenz for WMO) with a biannual updating. Data on disasters are gathered by
CRE/WMO (http://www.emdat.be/ ). A web based global groundwater information systems with a global groundwater monitoring
network is developed by IGRAC and would be a good base for groundwater data. These global information systems provide very
useful point information that may be use in sub-national analysis. They do not provide directly ‘national figures‘, apart from values
such as long term average (30 years) but are essential elements of modelling exercises at global level.
Data on large storage are gathered by ICOLD (large storage), but no regular gathering of information of small and middle
storages.Data on irrigated infrastructures are gathered by AQUASTAT on a global scale and updated regularly through a survey
process.
2.3 Changing realities of water uses
Total global freshwater use is estimated at about 4000 cubic kilometres (km3) a year. Population growth and rapid economic
development have accelerated freshwater withdrawals for multiple uses, mainly for provisioning services (basic services, food,
industry, energy). Water withdrawals have tripled over the last 50 years (WWDR3). This trend is explained largely by the rapid
increase in irrigation development stimulated by the food demand in the 1970s and by the continued growth of agricultural based
economies (with a large rural population). The industrial and urban based economies are often stabilizing their water abstractions.
The indicator proposed shows high variability of gross abstractions globally, both within sectors and across users. It focuses
on the uses putting pressure on the freshwater systems (surface and groundwater). The major water users are irrigation (70% of
abstractions), industry (20%) and domestic uses (10%).
The ‘green water uses’ are not considered here but represent significant water flows, and can influence climate locally. An estimated
6,400 km3 of rainwater is also used directly by agriculture for crop production in non-irrigated systems. Nature is in fact the most
important user, as an estimated 70,000 km3 of water is evaporated from forest, areas of natural (uncultivated) vegetation and
wetlands. Evaporation from manmade reservoirs is difficult to estimate, but it is considerable and estimated to reach 200 km3 per year
(12% of the storage capacity of the Aswan lake are lost every year by evaporation).
It is interesting to complete this information with an indication of the main sources of water. Surface water represents more than
70% of all water used (88 % of water used for energy and industrial purposes), and groundwater an additional 18% (46 % of
domestic uses). Three countries in the world are heavy users of non renewable (fossil) deep aquifer waters (Libya, Saudi Arabia and
Algeria) as it is their main source. In areas of scarce freshwater resources, brackish and saline waters or wastewater are used to meet
some of the demands.
Improving this indicator would require working on collecting improved data on withdrawals, as information is largely incomplete –
particularly for agriculture, the largest water user, and in particular compile historic data sets top follow trends (this is possible
partially for some OECD and European countries).
Figure 5. Sources of water use globally and for major sectors, 2000 (WWDR3)
Measurability
Water abstractions refers to freshwater taken from ground or surface water sources, either permanently or temporarily, and conveyed
to the place of use. If the water is returned again to a surface water source, abstraction of the same water by the downstream user is
counted again in compiling total abstractions (withdrawals). The in situ or on-stream uses (navigation, fishing, hydroelectricity etc.)
are important uses of water systems and have significant structural impacts on the water systems (e.g. fragmentation) but they cannot
be measured in volume terms and are therefore not reflected in the withdrawals statistics.
It should be borne in mind that the definition used by different countries may vary considerably and may have changed over time. In
general data availability is best for abstractions for public supply, representing about 10% of the total water abstracted in the world.
