Water Accounts and Statistics
(SEEA-Water and IRWS)
UN Statistics Division
17 July 2011
In general, water policy objectives can be grouped in the following four
quadrants:
I.
Improving drinking
water and sanitation
services
II.
Managing water
supply and demand
Water
Security
III.
Mitigating water
resources
degradation/
Improving quality of
water resources
IV.
Adapting to extreme
hydro-meteorological
events
SEEA-Water and IRWS provide the concepts and methods for measuring progress
towards the attainment of the objectives in each of the four quadrants, as well as higher
level indicators linking water security with human well being.
2
The four quadrants in plain English:
I.
Nature provides water,
but not the pipes
II.
Water is enough,
if it is well managed
Water
Security
III.
Water cleanses, but cannot
absorb all our wastes
IV.
Too much, too little,
better be prepared
Sustainable development requires good water and sanitation services for all, sharing
water to maximize benefits, making sure we don’t exceed water’s carrying capacity, and
getting ready for wet and dry years. The four quadrants are interconnected.
3
Quadrant I: Water and Sanitation
I.
Improving drinking
water and sanitation
services
Key information required:
• Number of people with access to improved
water and sanitation (MDG, from JMP)
• Tariffs, taxes and transfers
• All costs associated to the provision of the
services
• Investments in infrastructure and value of
infrastructure
• Volume of water abstracted, distributed
and lost (unaccounted for water)
Key indicators for this quadrant can be derived from the standardized information
collected according to SEEA-Water and IRWS concepts and definitions. The indicators
can therefore be consistent and comparable over time and space.
4
Quadrant II: Water Supply and Demand
Key information required:
II.
Managing water
supply and demand
• Renewable inland water resources
• Water abstracted/consumed/returned by
economic activities (including households).
• Water productivity by economic activity
• Trade off when allocating water
• Investments in hydraulic infrastructure and
value of existing infrastructure
Key indicators for this quadrant can be derived from the standardized information
collected according to SEEA-Water and IRWS concepts and definitions. The indicators
can therefore be consistent and comparable over time and space.
5
Quadrant III: Water Quality and Water Health
III.
Mitigating water
resources
degradation/
Improving quality of
water resources
Key information required:
• Waterborne pollutants emitted by economic
activity
• Pollutants removed as a result of treatment
• Water quality assessments in watercourses
• Regulatory services provided by ecosystems in
terms of assimilation of waterborne pollution
(water purification and disease control)
• Measures of the health of the water
ecosystems
Key indicators for this quadrant can be derived from the standardized information
collected according to SEEA-Water and IRWS concepts and definitions. The indicators
can therefore be consistent and comparable across time and space
6
Quadrant IV: Extreme Hydro-Meteorological Events
Key information required:
IV.
Adapting to extreme
hydrometeorological
events
• Water stocks and variations through time
(surface and groundwater).
• Investments for the storage and control of
water
• Disturbance prevention
• Regulatory services provided by the
ecosystems in terms of water flows
Key indicators for this quadrant can be derived from the standardized information
collected according to SEEA-Water and IRWS concepts and definitions. The indicators
can therefore be consistent and comparable across time and space
7
Economic policies are monitored using indicators which are widely accepted and
comparable between countries and through time. Most of the indicators are
derived from the standard concepts and definitions prescribed in the System of
National Accounts (SNA).
•
•
•
The first version of SNA was adopted in
1953.
The SNA has become a standard for
policy analysis throughout the world.
There is a lot of capacity developed in the
use of the SNA.
The environmental–economic accounts were developed from the SNA concepts and
definitions. The process to approve the system of environmental economic accounts is as
strict as the one followed for the approval of SNA.
8
Recently, the United Nations Statistical Commission (UNSC) adopted the System
of Environmental Economic Accounts for Water (SEEA-Water) and the
International Recommendations for Water Statistics (IRWS).
The UNSC is a functional commission of the UN
Economic and Social Council (ECOSOC). It is the
highest decision making body for international
statistical activities, especially the setting of
statistical standards, the development of concepts
and methods and their implementation at the
national and international level.
SEEA-Water and IRWS are key ingredients for the development of information systems
for the design and evaluation of water policies.
9
In 2007 the UNSC adopted the SEEA-Water. It covers all the physical and
economic stocks and flows associated with water. It also covers emissions of
pollutants and water quality.
In 2010 the UNSC adopted the IRWS, designed to
assist countries in the collection, compilation and
dissemination of internationally comparable water
statistics.
The SEEA-Water and the IRWS provide the framework for developing indicators that are
comparable through time and space.
10
More than fifty countries around the world are doing or planning to do water
accounts.
Countries doing significant progress are: Australia, Brazil, Canada, China, Colombia,
Dominican Republic, Ecuador, Egypt, Guatemala, Jordan, Mexico, Netherlands, Oman
and South Africa, among others.
11
We speak the language of our particular discipline, our specific field of expertise.
Inter-disciplinary work is sometimes similar to building the Babel tower.
Traducción libre
“When I use a word,” Humpty Dumpty said, in a
rather a scornful tone, “it means just what I
choose it to mean—neither more nor less.”
“The question is,” said Alice, “whether
you can make words mean so many different
things.”
“The question is,” said Humpty Dumpty, “which
is to be master
that’s all.”
This presentation concentrates on concepts, rather than words.
building blocks of water accounts from a system’s perspective.
It reviews the basic
Esperanto was developed hoping (Mr. Hope) to increase understanding between
nations and cultures. Perhaps there is a need for practical approaches that
promote common understanding with small training investments.
The solution of environmental problems requires simple intuitive languages that can help
build shared visions. Correct coding and standardization is also required.
13
The language of “stocks” and “flows” is useful to talk about dynamic processes. A
sentence has a noun and a verb. The “stocks” are like the nouns and the “flows”
are like the verbs. For example, by saving I increase money saved.
The example above can be expressed as follows in mathematical terms.
𝜕𝑀𝑜𝑛𝑒𝑦
= 𝑠𝑎𝑣𝑖𝑛𝑔 𝑡 − 𝑠𝑝𝑒𝑛𝑑𝑖𝑛𝑔(𝑡)
𝜕𝑡
With these simple elements it is possible to describe the dynamics of complex systems.
14
The following example refers to a closed system (there are no clouds). The
example tells us that by moving the energy stored is depleted, but at the same
time the position is changed.
The example above can be expressed as follows in mathematical terms.
𝜕𝐸𝑛𝑒𝑟𝑔𝑦
= −𝑚𝑜𝑣𝑖𝑛𝑔 𝑡
𝜕𝑡
𝜕𝑃𝑜𝑠𝑖𝑡𝑖𝑜𝑛
= 𝑚𝑜𝑣𝑖𝑛𝑔(𝑡)
𝜕𝑡
The equations shown above can be solved by integration of the function that describes the
movement. Everything has to be expressed in the same measuring units.
15
In a similar way the transactions in a society can be described. Even though the
example is very simple, more detail can be added to communicate useful
information for decision making.
All the flows and stocks have to be expressed in the same measuring units. One way of
achieving this is using monetary units calculated with uniform criteria.
16
The following diagram shows a simplified natural water cycle.
The diagram represents a closed system in which the mass has to be conserved.
17
The economy can be included in the water cycle. For simplicity not all the flows
are shown.
Due to the complexities associated with measuring the atmospheric and oceanic stocks, it
is more practical to use an open system model (with clouds showing the boundaries)
18
The following diagram shows a simplified open model. The sea and atmosphere
are left out.
The diagram represents a closed system in which the mass has to be conserved.
19
The Inland Water Resources can be divided into surface water, groundwater and
soil water.
The diagram represents a closed system in which the mass has to be conserved.
20
Flows of water being used by the economy.
21
All the flows and stocks can be presented in a “hypermatrix.”
Each element in the “hypermatrix” has a corresponding concept in SEEA-Water
22
The following “hypermatrix” shows the relationships with IRWS.
Groundwater
Soil Water
D.4
Industries
ADDITIONS TO STOCKS:
Total inflow in the year
Stocks at the end of the
year
Addition of columns
Initial stocks - SUBTRACTIONS +
ADDITIONS
Stocks at the beginning of
the year
Industries & Households
Rest of the world
Sea
Water consumption
A.1.1
A.1.2
A.1.3
A.1.4
A.1.5
E.1.2
A.2
E.1.3
Not in IRWS
E.3
Sea
Rest of the world
Soil Water
Groundwater
Snow, ice and glaciers
Wetlands
Rivers and streams
Lakes
Artificial reservoirs
D.2 From surface water to groundwater
SUBTRACTIONS TO STOCKS:
total outflow in the year
Snow, ice and glaciers
Addition of rows
Wetlands
A.1
E.1.1 From surface water
Rivers and streams
D.3. Between surface water resources
C.2.1 Outflow of water to downstream territories
Lakes
E.2
C.2.2 Outflow of water to the sea
Artificial reservoirs
B.1 Precipitation
Not in IRWS
Surface water
STOCKS
D.1 From surface to groundwater
Atmosphere
C.1. Evapotranspirationf from inland waters
Atmosphere
water
flows
Surface water
C.1. Evapotranspirationf from inland waters
FLOWS
B.2 Inflow of water from upstream territories
H.1.1 Returns to surface water, I.1 & I.2
F.3 &G.3
H.1.2, I.1 H.3, I.1 H.2, I.1 F.2, F.5, F.1 & F.4,
& I.2 & I.2 & I.2 I.1 & I.2 G.1 & G.4
Complement
Each element in the “hypermatrix” has a corresponding element in the IRWS.
23
The following diagram shows a simplified natural water cycle.
The diagram represents a closed system in which the mass has to be conserved.
24
Indicators can be derived from the “hypermatrix”
Example:
E.1.1 + E.1.2
Water stress =
B.1 + C.1+B.2-C.2.1
It is important to use the data provided by countries through the
UNSD/UNEP questionnaire, which is sent every two years.
The indicators are therefore comparable through space and time.
25
EECCA Indicators:
1. Total water use: consider the MDG 7.5 indicator. It might be better to
measure or estimate abstractions of water by agriculture (ISIC 1-3),
water supply industry (ISIC 36), cooling for electricity (ISIC 35 without
hydroelectricity) and all other industries.
2.
Water supply industry: consider abstractions per capita by water supply
industry (ISIC 36), losses and the amount of water that is actually
supplied to households.
3.
Population connected to wastewater treatment. Consider MDG 7.9
indicator, included in the International Recommendations for Water
Statistics (IRWS), table 4.16 of data items.
4.
Wastewater treatment facilities. Consider waterborne gross emissions
and the emissions removed by wastewater treatment facilities.
Emissions can be measured in terms of BOD and COD, among others.
5.
Concentration of pollutants in seawater and sediments. Consider
waterborne emissions discharged to the sea in terms of BOD and COD,
among others.
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Thank you!
Ricardo Martinez-Lagunes (martinezr@un.org)