Personal tools

next
previous
items

Skip to content. | Skip to navigation

Sound and independent information
on the environment

You are here: Home / Data and maps / Indicators / Urban waste water treatment / Urban waste water treatment (CSI 024/WAT 005) - Assessment published Jan 2009

Urban waste water treatment (CSI 024/WAT 005) - Assessment published Jan 2009

Indicator Assessment Created 29 Nov 2007 Published 29 Jan 2009 Last modified 09 Jan 2015, 03:24 PM
Topics: ,

Generic metadata

Topics:

Water Water (Primary topic)

Tags:
waste water treatment | csi | waste water | soer2010 | water | water resources | thematic assessments | waste
DPSIR: Response
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
Indicator codes
  • CSI 024
  • WAT 005
Geographic coverage:
Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, United Kingdom
 
Contents
 

Indicator definition

Percentage of population connected to primary, secondary and tertiary wastewater treatment plants. The indicator illustrates:

1. changes in wastewater treatment in the regions of Europe since the 1980s;

2. conformity (in terms of providing tertiary treatment) by Member States with the requirement to provide, by 31 December 1998, stringent treatment for agglomerations with population equivalent (p.e.) more than 10 000 that discharge into sensitive areas;

3. levels of urban wastewater treatment in large cities in the EU (agglomerations >150 000 p.e.).

Units

Percentages of population connected to primary, secondary and tertiary wastewater treatment.


Key policy question: How effective are existing policies in reducing loading discharges of nutrients and organic matter?

Key messages

Wastewater treatment in all parts of Europe has improved during the last 15-20 years. The percentage of the population connected to wastewater treatment in the southern, south-eastern and eastern Europe has increased during last ten years, but is still relative low compared to the central and northern Europe.

Changes in wastewater treatment in regions of Europe between 1990 and 2005

Note: Only countries with data from (almost) all periods were included, the numbers of countries are given in parentheses

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Changes in wastewater treatment in northern countries of Europe between 1980s and 2005

Note: N/A

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Changes in Changes in wastewater treatment in countries of Europe between 1980s and 2005 (Western)

Note: N/A

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Changes in wastewater treatment in countries of Europe between 1980s and 2005 (Southern)

Note: N/A

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Changes in wastewater treatment in countries of Europe between 1980s and 2005 (East)

Note: N/A

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Changes in wastewater treatment in countries of Europe between 1995 and 2005 (South-Eastern)

Note: N/A

Data source:

EEA-ETC/WTR based on country data reported to OECD/EUROSTAT Joint Questionnaire. Data are available at Eurostat data tables.

Downloads and more info

Key assessment

The main objective of the Urban Waste Water Treatment (UWWT) Directive is to protect the environment from the adverse effects of urban waste water discharges and discharges from certain industrial sectors and the measures concerns the collection, treatment and discharge of most of the waste water.

As a rule, the UWWT Directive provides for biological waste water treatment (secondary treatment), and thus a drastic reduction of the biodegradable pollution in waste water - which otherwise would severely impact on oxygen balance and ecosystems of our waters. In the catchments of particularly sensitive waters (sensitive areas), such as those suffering from eutrophication, more stringent treatment measures are required, to additionally eliminate nutrient pollution (nitrogen and phosphorus) from waste water (tertiary treatment).

 

The success indicators used in this assessment to measure the reduction in discharges of nutrients and organic matter from urban waste water to European surface waters are:

1. Percentage of population connected to waste water treatment.

2. Percentage of waste water given tertiary treatment.

 

1. Percentage of population connected to waste water treatment (Fig. 1 and the individual countries in Fig. 2-6). In northern and also in southern European countries more than 80 % of the population is connected to waste water treatment. In sparcely populated countries with a relative high proportion of the population living in scattered dwellings these dwelling are not connected to collecting systems and normally served by individual waste water treatment (e.g. septic tanks). In central Europe more than 90 % is connected. In eastern Europe only 50 % is connected (last data are from 2002, so this percentage may be higher now), whereas in south-eastern Europe (Turkey, Bulgaria and Romania) there is only 35 % that are connected to waste water treatment plants.

 

2. Percentage of waste water given tertiary treatment (yellow color on Fig. 1 to 6). Most of the population in the northern countries is connected to waste water treatment plants with the highest levels of treatment (tertiary), which efficiently removes nutrients (phosphorus or nitrogen or both) and organic matter. More than half of the waste water in central European countries is subject to tertiary treatment. In southern and eastern Europe only 20 % get tertiary treatment. Around half of the wastewater in southern European countries and 25 % in eastern Europe receive only secondary treatment. In south-eastern Europe the level of tertiary treatment is minor (< 5 %), whereas 20 % is subject to secondary treatment.

 

Specific policy question: What is the level of the Urban Waste Water Treatment Directive (91/271/ECC) implementation in large cities of the EU Member States?

Number of EU15 agglomerations of more than 150 000 p.e. by treatment level, situation on 1st January 2003.

Note: N/A

Data source:

DGENV 2007

Downloads and more info

Specific assessment

The lastest from 2007 EU Commissions Urban Waste Water Treatment (UWWT) Directive implementation report  can be found on http://ec.europa.eu/environment/water/water-framework/implrep2007/index_en.htm. According to this report waste water treatment in 349 out of the 571 big cities of Europe complied with the treatment requirements of the UWWT Directive without any need for updating the treatment. 122 of the 571 big cities with population equivalent more than 150 000 did not have a sufficient standard of treatment on 1st of January 2003 to meet the objectives of the UWWT Directive. 17 had no treatment at all. No information is available for four cities. These big cities account for 55% of the total waste water pollution load of organic matter covered by the 1998 and 2000 UWWT Directive deadlines (i.e. of > 470 mil. p.e.). 

 

Further information can be found in the WISE section on Urban Waste Water Treatment Directive http://www.eea.europa.eu/themes/water/water-pollution/prevention-strategies/urban-waste-water-treatment-directive.

 

Specific assessments of waste water treatment in different countries:

Northern Europe: Most of the waste water (80%) in Finland, Sweden and Norway receives tertiary treatment (Fig. 2), while in Iceland the waste water from half of the population is not treated at all and the other half only receive primary treatment. The trends in the rate of national population connected to the UWWTPs are affected by changes in the ratio of rural/urban population as well as by increasing use of separate individual treatment plants in rural areas.

 

Central Europe: In Switzerland, Germany, Denmark, Austria and the Netherlands most of the population is connected to the tertiary treatment (Fig. 3). In Ireland more than 30 % has no treatment at all and more than 40 % of waste water receives only primary treatment. In Belgium more than 60 % of the population had no treatment at all at the time of the last reporting (1998), but national state of the environment reports indicate marked improvement in waste water treatment over the last decade.

 

Southern Europe: The best situation is in Spain where more than 90% of population is connected to treatment systems (fig. 4). The worst situation is in Malta, where almost 90 % of population has no treatment of their waste water at all. In France 80 % is connected, whereas the percentage connected to waste water treatment in Italy, Greece and Portugal is higher than 60 %,  higher than  50 % and ca. 40 %, respectively. Tertiary treatment is minor in this region in general with maximum 20 % of the total waste water (Italy, France and Spain), and less than 10 % in Greece and Portugal

 

Eastern Europe:  More than 65 % of the population in the Czech Republic, Estonia, Latvia and Lithuania is connected to the waste water treatment, and roughly half of the waste water connected to treatment systems is given tertiary treatment (fig. 5). For Poland and Hungary around 60 % of the population is connected to waste water treatment systems. In Poland about half of the connected wastewater are given tertiary treatment, whereas in Hungary only 10 % gets tertiary treatment. The worst situation is in Slovenia, where almost 70 % of the population is not connected to waste water treatment systems. For Slovakia there is no detailed information on treatment type available.

 

South-Eastern Europe: In south eastern European countries (Turkey, Bulgaria, Romania) only around 40% of the population is connected to the waste water treatment, with most of the connected waste water receiving only secondary or primary treatment (fig. 6). Only in Turkey there is a small proportion of the waste water that receives tertiary treatment.

 

Data sources

Policy context and targets

Context description

The Urban Wastewater Treatment Directive (UWWT) prescribes the level of treatment required before discharge. It requires Member States to provide all agglomerations of more than 2 000 population equivalents (p.e.) with collecting systems. Secondary treatment (i.e. biological treatment) must be provided for all agglomerations of more than 2 000 p.e. discharging into fresh waters. Special requirements with intermediate deadlines depending on the sensitivity of the receiving waters are placed on agglomerations of more than 10 000 p.e. with various size classes of agglomerations. The performance of the treatment is assessed using 5 different determinands (BOD, COD, TSS, Ntot and Ptot). In the EU Member States, there are about 25 000 agglomerations with more than 2 000 p.e., the population is 501 million inhabitants and the overall generated load of  621 million p.e.

For agglomerations smaller than described above and those equipped with a collecting system, the treatment must be appropriate, meaning that the discharge allows the receiving waters to meet the relevant quality objectives.
The WFD is asking for the estimation and identification of significant point and diffuse source pollution, in particular by substances listed in Annex VIII, from urban, industrial, agricultural and other installations and activities, based, inter alia, on information gathered under Articles 15 and 17 of Directive 91/271/EEC and other Directives. From the substances listed in the Annex VIII, the following are important for the indicator : substances which have an unfavourable influence on the oxygen balance (and can be measured using parameters such as BOD, COD, etc.), materials in suspension, and substances which contribute to eutrophication (in particular, nitrates and phosphates). Member States should thus take the necessary steps to build a data collection system able to provide these data, urban source being one of the sources listed. The ultimate aim of this is to reach the target of the WFD that is a good chemical and biological status for all waters in 2015, the discharge of substances being one of the major problems to face.

Targets

The Urban Waste Water Treatment Directive (UWWTD; 91/271/EEC) aims to protect the environment from the adverse effects of urban wastewater discharges. It prescribes the level of treatment required before dischargeand has to be fully implemented in the EU-15 countries by 2005 and in the ten new Member States by 2008 - 2015. The directive requires Member States to provide all agglomerations of more than 2 000 population equivalent (p.e.) with collecting systems and all wastewaters collected to be provided with appropriate treatment by 2005. Secondary treatment (i.e. biological treatment) must be provided for all agglomerations of more than 2 000 p.e. that discharge into fresh waters, while more advanced treatment (tertiary treatment) is required for discharges into sensitive areas. To help minimise pollution from various point sources, the Integrated Pollution Prevention and Control directive, which came into force 1996, has a set of common rules on permitting for industrial installations.

The achievements through the UWWTD and the IPPC directive have to be seen as an integrated part of objectives under the Water Framework Directive (WFD) which aim at a good chemical and biological status for all waters by 2015.

Related policy documents

  • COM(2004) 248 final
    Implementation of Council Directive 91/271/EEC of 21 May 1991 concerning urban waste water treatment, as amended by Commission Directive 98/15/EC of 27 February 1998
  • Urban wastewater treatment summary report
    Summary report on: the identification of sensitive areas by the Member States; the measures implemented by the Member States with the view to the deadline of 31 December 1998; wastewater treatment in major cities; verification of the identification of sensitive areas by the Commission.

Methodology

Methodology for indicator calculation

Eurostat data are used and aggregated in groups of countries. Average of percentages connected to each treatment type, weighted by total population in each country:

Formula:

National resident population = "WW0_1 National resident population" if available or else "Table: pjan, unit: inhabitant, Population by sex and age on 1. January of each year"

% of population connected to a type of treatment for one area = sum of (National resident population X "WW0_2_1 Urban waste water treatment of primary treatment"or

"WW0_2_2 Urban waste water treatment of secondary treatment" or

"WW0_2_3 Urban waste water treatment of tertiary treatment") or

"WW0 5: Urban wastewater collecting system without treatment"

EU aggregated and national data are used as presented on DG Environment's web page and reports.

EU aggregated values representing the type of treatment applied in the wastewater treatment plants of 586 big cities/big dischargers (250,2 mil. p.e.) reported in 2011 by the Member States and Norway were retrieved from the latest version of Waterbase  via a series of subsequent queries linking information on agglomerations with total generated load higher than 150 000 p.e., treatment plants serving those agglomerations and the information on the percentage of total generated load treated in particular treatment plants. First, the sequence of scripts retrieved disaggregated information at the big city/big discharger level. Disaggregated information was then aggregated at the national level.

Methodology for gap filling

For the Eurostat dataset, gap fillings were made, by using figures provided by the respective NFPs during the review process or by replacing data available in Newcronos.

Methodology references

No methodology references available.

Uncertainties

Methodology uncertainty

For the assessment shown in Figure 1, countries have been grouped to show the relative contribution on a larger statistical basis and to overcome the incomplete nature of the data. Complete dataset (ie data available for all years ad all countries) is not available for either of the geographic groups except for South-eastern countries (since the beginning of 2000 ies). Aggregated values are calculated only for the years for which the most complete dataset (with regard to number of responding countries) is available.

Data sets uncertainty

 

Rationale uncertainty

Data gained from the UWWTD focuses on the performance of the treatment plant alone. But wastewater treatment systems could also include sewer networks with storm water overflows and storages which are complex and whose overall performance is difficult to assess. In addition to the treatments covered by the UWWTD there are other possible treatments, mostly industrial, but also independent treatments of smaller settlements outside urban agglomerations not included in UWWTD reporting. Compliance with the levels defined in the directive therefore does not guarantee that there is no pollution due to urban wastewater.

In addition Urban Waste Water Treatment is the main waste water treatment used across the EEA area, but there are other possible treatments that are treatment in Other Waste Water Treatment, mostly industrial, or in independent treatments. Furthermore there are differences in how countries have interpreted and implemented the Directive leading to differences in the data reported. There are especially variations in the definitions of different classes of treatment between countries (classes based on performance or on design capacity and tertiary treatment for N, P or organic matter) that in turn lead to differences in the level of purification attributed by the countries to the classes. These differences all the more emphasize the problem of using types of treatment plant as a proxy for the level of purification. Member States have also been taken to court by the European Commission because of insufficient application of the Directive.

More information about this indicator

See this indicator specification for more details.

Contacts and ownership

EEA Contact Info

Peter Kristensen

Ownership

EEA Management Plan

2010 (note: EEA internal system)

Dates

Frequency of updates

Updates are scheduled every 2 years
European Environment Agency (EEA)
Kongens Nytorv 6
1050 Copenhagen K
Denmark
Phone: +45 3336 7100