Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
Eurostat, the Statistical Office of the European Union
1.2. Contact organisation unit
E2: Environmental statistics and accounts; sustainable development
1.3. Contact name
Restricted from publication
1.4. Contact person function
Restricted from publication
1.5. Contact mail address
2920 Luxembourg LUXEMBOURG
1.6. Contact email address
Restricted from publication
1.7. Contact phone number
Restricted from publication
1.8. Contact fax number
Restricted from publication
2.1. Metadata last certified
11 July 2024
2.2. Metadata last posted
11 July 2024
2.3. Metadata last update
11 July 2024
3.1. Data description
Eurostat's water statistics on national level (env_nwat) include the following data sets based on the OECD/Eurostat Joint Questionnaire on Inland waters (JQ-IW):
Dataset code
Dataset label
Data source: JQ-IW table
ENV_WAT_LTAA
Renewable freshwater resources – long term annual averages
T1 Renewable freshwater resources
ENV_WAT_RES
Renewable freshwater resources
T1 Renewable freshwater resources
ENV_WAT_ABS
Annual freshwater abstraction by source and sector
T2 Annual freshwater abstraction by source and by sector
ENV_WAT_USE
Water made available for use
T3 Water made available for use
ENV_WAT_CAT
Water use by supply category and economical sector
T4 Water use by supply category and by sector
ENV_WAT_POP
Population connected to public water supply
T4 Water use by supply category and by sector
ENV_WAT_BAL
Water use balance
Several
ENV_WAT_CON
Population connected to wastewater treatment plants
T5 Population connected to wastewater treatment plants
ENV_WAT_SPD
Sewage sludge production and disposal
T7 Sewage sludge production and disposal (in dry substance)
ENV_WAT_GENV
Generation and discharge of wastewater in volume
T8 Generation and discharge of wastewater
ENV_WAT_GENP
Generation and discharge of wastewater by pollutant
T8 Generation and discharge of wastewater
3.2. Classification system
The OECD/Eurostat Joint Questionnaire on Inland Waters records a number of water related characteristics, which are broken down by the following dimensions and related code lists:
Water process (wat_proc)
Water sources (wat_src)
Waste-water treatment plants (ww_tp)
Waste-water generation, treatment and discharge (ww_gtd)
Statistical classification of economic activities (nace_r2)
Wastewater treatment plants parameter (ww_tpar)
Substances (substances)
3.3. Coverage - sector
In principle all NACE sectors and private households are covered by the data set produced.
3.4. Statistical concepts and definitions
Statistical concepts and definitions for the OECD/Eurostat Joint Questionnaire on Inland Waters are laid down in the following:
Statistical units differ, depending on the various data sources used to compile water statistics.
3.6. Statistical population
All inland water flows.
3.7. Reference area
EU Member States, EFTA countries, EU candidate countries and potential candidates. EU totals or averages are not yet calculated as there are many data gaps due to the voluntary nature of reporting.
3.8. Coverage - Time
Depending on availability of data for different countries the period between 1970 - 2022 is covered
3.9. Base period
Not applicable.
For water resources, water abstraction and water use: million m³
For population connected to sewer systems and wastewater treatment plants: % of resident population
For sewage sludge production and disposal: million kg (dry substance)
For wastewater generation and discharge:
Volume: million m³ / year
BOD and COD: 1000 kg O2 / day
Suspended solids, N, P: 1000 kg / day
The calendar year
6.1. Institutional Mandate - legal acts and other agreements
The data collection is voluntary. Eurostat’s work on water statistics is covered by the European Statistical Programme.
6.2. Institutional Mandate - data sharing
The data collection is a common action of OECD and Eurostat.
Data are also shared with the European Environment Agency (EEA) and provided to the Water Information System for Europe (WISE), the European data centre for water. Data are as well used by the UN Statistics Division and FAO.
7.1. Confidentiality - policy
Regulation (EC) No 223/2009 on European statistics (recital 24 and Article 20(4)) of 11 March 2009 (OJ L 87, p. 164), stipulates the need to establish common principles and guidelines ensuring the confidentiality of data used for the production of European statistics and the access to those confidential data with due account for technical developments and the requirements of users in a democratic society.
7.2. Confidentiality - data treatment
Not applicable
8.1. Release calendar
Not applicable
8.2. Release calendar access
Not applicable
8.3. Release policy - user access
In line with the Community legal framework and the European Statistics Code of Practice, Eurostat disseminates European statistics on Eurostat's website (see item 10 - 'Accessibility and clarity') respecting professional independence and in an objective, professional and transparent manner in which all users are treated equitably. The detailed arrangements are governed by the Eurostat protocol on impartial access to Eurostat data for users.
From 2019 onwards, the data collection is executed every year, and with this the database is updated at once a year.
10.1. Dissemination format - News release
not available
10.2. Dissemination format - Publications
Statistics explained: section water statistics
There is no regular publication dedicated just to water statistics. However data are used for the production of different Eurostat sample publications.
10.3. Dissemination format - online database
Please consult free data on-line or refer to contact details.
Data are disseminated free through Eurostat's website.
10.4. Dissemination format - microdata access
not applicable
10.5. Dissemination format - other
not applicable
10.6. Documentation on methodology
Documentation on the collection of the water data collection can be found in the manual for water statistics.
10.7. Quality management - documentation
Quality is assured by internal data validation processes for which public documentation is not yet available.
11.1. Quality assurance
Quality is assured by internal data validation processes.
Contributing countries are requested to document their approach by means of standardized quality reports.
11.2. Quality management - assessment
Data are checked for logical consistency within the tables, in between tables, in between countries, as well as over time.
12.1. Relevance - User Needs
DG Environment, DG Agriculture and Rural Development (Agri), Joint Research Centre (DG JRC), DG Climate Action
OECD
EEA (European Environment Agency)
UN Statistics Division
UN FAO
European Court of Auditors
European Investment Bank
12.2. Relevance - User Satisfaction
No information available
12.3. Completeness
There are data gaps of different size and character for all participating countries.
13.1. Accuracy - overall
No information available
13.2. Sampling error
Not applicable
13.3. Non-sampling error
Not applicable
14.1. Timeliness
In case of regular reporting, the time lag between the period covered by the data and publication of the data amounts up to 16 -18 months.
14.2. Punctuality
The data collection launched in 2023 had a response of 39 countries of which 5 countries reported within three months after the deadline.
15.1. Comparability - geographical
In principle geographical comparability is good, but interpretability of country data is limited for some parameters due to aggregation of regional differences.
15.2. Comparability - over time
Comparability over time is generally good, but can be limited due to data gaps and breaks in series.
15.3. Coherence - cross domain
Data on sewage sludge treatment are also reported under the waste statistics Regulation but with limited comparability.
The data are revised whenever a new questionnaire is filled in: historical data are pre-filled, and National Statistical Institutes are asked to revise their data and make corrections wherever necessary.
The questionnaire itself is revised after discussions at the meetings of the relevant OECD and Eurostat bodies. In doing so, Eurostat strives to keep the balance between consistency of time series and adaptation to the users' needs and to progress in science and technology.
17.2. Data revision - practice
Reported errors are assessed for seriousness to determine whether they should trigger a correction of already disseminated data. Reported errors are corrected in the disseminated data as soon as the correct data have been validated.
New data are only used to update disseminated data if provided according to the provision schedule set by Eurostat, or in the case of reported errors.
18.1. Source data
The default operational source of the data is the National Statistical Institute on which no specific data collection method is imposed by Eurostat. In a few countries, collection of all or part of the data is delegated to other administrations, such as e.g. environment agencies operating under supervision of the ministry of the environment.
The data collection uses the "Joint OECD/Eurostat questionnaire on inland water (JQ-IW)"
18.2. Frequency of data collection
The data collection is executed annually by Eurostat, the frequency on national level depends on country and issue.
18.3. Data collection
National Statistical Institutes collect the data from a variety of data sources, including regional or local authorities, environmental administrations and industry. Where suitable and necessary, they apply own surveys and statistical estimation methods.
The data collection is done every calendar year, as well as gap-filling and corrections for earlier reference years.
Eurostat collects the data using questionnaires presented as SDMX-compatible Excel files. Each of the 7 tables of the Joint Questionnaire comes as a separate file and is released in the EDAMIS system (Eurostat single entry point). Supplementary information relevant for filling in the tables (e.g. data collection manual) is made available on Circabc for download by the Member States. The filled-in questionnaires are accessible by Eurostat within the EDAMIS system. Apart from the automatic EDAMIS monitoring files, a working file is kept up-to-date to monitor the incoming replies.
Following data is collected for every country:
Renewable fresh water resources;
Annual fresh water abstraction by source and by sector and other sources of water (marine and brackish water, desalinated water, reused water);
Water use by supply category, by sector and by industrial activities;
Resident population connected to wastewater collecting systems and to wastewater treatment plants;
Sewage sludge production and disposal;
Generation (by source and by sector) and discharge (by type of collecting system) of wastewater
18.4. Data validation
Data is filled in a tailor-made database (WATER in MDT), and Eurostat checks the data for plausibility, e.g. for logical consistency in several dimensions and for unusual changes in time series. All detected problems are reported and treated in close collaboration with the National Statistical Institutes and/or the relevant experts in the countries. Once validation is done, the data are uploaded to Eurostat's website ('Eurobase').
The data validation is done following the validation levels 0 to 3 and partly level 5 (see concept of validation levels), as proposed in the VIP Validation project. Some basic quality checks in the file itself, intra-file checks, as well as comparison with other files referring to the same statistical domain followed by "intra-domain and intra-source checks" are of relevance: it includes revision checks, time series checks and inter-dataset checks, as well as some mirror checks.
Validation level 4 is not of use for us, but validation level 5 is partly used for some data checking with our partners outside the Institution (eg. EAA).
18.5. Data compilation
Eurostat calculates some indicators, e.g. "per capita" values, and water statistics are used in the indicator sets for the assessment of sustainable develoment and resource effciency.
18.6. Adjustment
Not applicable
Explanatory footnotes provided by the countries are not directly available via Eurostat's dissemination database. The content is made accessible via the metadata Annex sheet (in preparation).
Eurostat's water statistics on national level (env_nwat) include the following data sets based on the OECD/Eurostat Joint Questionnaire on Inland waters (JQ-IW):
Dataset code
Dataset label
Data source: JQ-IW table
ENV_WAT_LTAA
Renewable freshwater resources – long term annual averages
T1 Renewable freshwater resources
ENV_WAT_RES
Renewable freshwater resources
T1 Renewable freshwater resources
ENV_WAT_ABS
Annual freshwater abstraction by source and sector
T2 Annual freshwater abstraction by source and by sector
ENV_WAT_USE
Water made available for use
T3 Water made available for use
ENV_WAT_CAT
Water use by supply category and economical sector
T4 Water use by supply category and by sector
ENV_WAT_POP
Population connected to public water supply
T4 Water use by supply category and by sector
ENV_WAT_BAL
Water use balance
Several
ENV_WAT_CON
Population connected to wastewater treatment plants
T5 Population connected to wastewater treatment plants
ENV_WAT_SPD
Sewage sludge production and disposal
T7 Sewage sludge production and disposal (in dry substance)
ENV_WAT_GENV
Generation and discharge of wastewater in volume
T8 Generation and discharge of wastewater
ENV_WAT_GENP
Generation and discharge of wastewater by pollutant
T8 Generation and discharge of wastewater
11 July 2024
Statistical concepts and definitions for the OECD/Eurostat Joint Questionnaire on Inland Waters are laid down in the following:
Statistical units differ, depending on the various data sources used to compile water statistics.
All inland water flows.
EU Member States, EFTA countries, EU candidate countries and potential candidates. EU totals or averages are not yet calculated as there are many data gaps due to the voluntary nature of reporting.
The calendar year
No information available
For water resources, water abstraction and water use: million m³
For population connected to sewer systems and wastewater treatment plants: % of resident population
For sewage sludge production and disposal: million kg (dry substance)
For wastewater generation and discharge:
Volume: million m³ / year
BOD and COD: 1000 kg O2 / day
Suspended solids, N, P: 1000 kg / day
Eurostat calculates some indicators, e.g. "per capita" values, and water statistics are used in the indicator sets for the assessment of sustainable develoment and resource effciency.
The default operational source of the data is the National Statistical Institute on which no specific data collection method is imposed by Eurostat. In a few countries, collection of all or part of the data is delegated to other administrations, such as e.g. environment agencies operating under supervision of the ministry of the environment.
The data collection uses the "Joint OECD/Eurostat questionnaire on inland water (JQ-IW)"
From 2019 onwards, the data collection is executed every year, and with this the database is updated at once a year.
In case of regular reporting, the time lag between the period covered by the data and publication of the data amounts up to 16 -18 months.
In principle geographical comparability is good, but interpretability of country data is limited for some parameters due to aggregation of regional differences.
Comparability over time is generally good, but can be limited due to data gaps and breaks in series.
