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 2013

Urban waste water treatment (CSI 024/WAT 005) - Assessment published Jan 2013

Indicator Assessment Created 26 Mar 2012 Published 31 Jan 2013 Last modified 09 Jan 2015, 03:25 PM
Topics: ,

Generic metadata

Topics:

Water Water (Primary topic)

Tags:
water resources | waste water treatment | thematic assessments | soer2010 | urban waste water
DPSIR: Response
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
Indicator codes
  • CSI 024
  • WAT 005
Dynamic
Temporal coverage:
1980, 1985, 1990-2010
Geographic coverage:
Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, England, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Scotland, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, United Kingdom, Wales
 
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 over the last ten years. Latest values of population connected to wastewater treatment in the Southern countries are comparable to the values of Central and Northern countries, whereas the values of Eastern and South-Eastern Europe are still relatively low compared to Central and Northern Europe.

Changes in wastewater treatment in regions of Europe between 1990 and 2012

Note: This figure illustrates the percentage population per European region connected to a waste water collection and treatment systems (UWWTPs) over the period 1980 to 2012. In addition, a breakdown by treatment type is portrayed. Numbers in brackets indicate number of countries in the aggregations.

Data source:
Downloads and more info

Changes in wastewater treatment in Northern European countries between 1980s and 2009

Note: This figure illustrates the percentage population in Norhern European countries connected to a waste water collection and treatment systems (UWWTPs) over the period 1980 to 2009. In addition, a breakdown by treatment type is portrayed.

Data source:
Downloads and more info

Changes in wastewater treatment in Central European countries between 1980s and 2009

Note: This figure illustrates the percentage population in Central European countries connected to a waste water collection and treatment systems (UWWTPs) over the period 1980 to 2009. In addition, a breakdown by treatment type is portrayed.

Data source:
Downloads and more info

Changes in wastewater treatment in Southern European countries between 1980s and 2009

Note: This figure illustrates the percentage population in Southern European countries connected to a waste water collection and treatment systems (UWWTPs) over the period 1980 to 2009. In addition, a breakdown by treatment type is portrayed.

Data source:
Downloads and more info

Changes in wastewater treatment in Eastern European countries between 1980s and 2009

Note: This figure illustrates the percentage population in Eastern European countries connected to a waste water collection and treatment systems (UWWTPs) over the period 1980 to 2009. In addition, a breakdown by treatment type is portrayed.

Data source:
Downloads and more info

Changes in wastewater treatment in South- Eastern European countries between 1990s and 2009

Note: This figure illustrates the percentage population in South - Eastern European countries connected to a waste water collection and treatment systems (UWWTPs) over the period 1990 to 2009. In addition, a breakdown by treatment type is portrayed.

Data source:
Downloads and more info

Key assessment

The main objective of the Urban Waste Water Treatment (UWWT) Directive and national legislation for non-EU countries is to protect surface waters from the adverse effects of wastewater discharges. This is achieved through the requirement for collection and treatment of wastewater in all settlements (agglomerations) and areas of economic activity with a population equivalent (p.e.) larger than 2000. As a rule, the UWWT Directive provides for biological treatment of waste water (secondary treatment), which would otherwise deplete oxygen levels in receiving waters, threatening aquatic ecosystems. In catchments with particularly sensitive waters (sensitive areas), such as those suffering from eutrophication, more stringent tertiary waste water treatment measures are required, in order to substantially reduce nutrient pollution (nitrogen and phosphorus) from waste water. The connection of population to sewerage systems is dependent both on sanitation services provided and on demography (population density). A low percent of connection in agglomerations can be due to lack of financial resources (or priority) for providing the sanitation services or due to a high proportion of the population living outside agglomerations where individual sanitation systems is the most feasible solution.
Some independent appropriate systems (IAS) may exhibit same treatment efficiencies as larger urban waste water treatment plants.

Success indicators used in this assessment to measure the reduction of discharged loads of nutrients and organic matter from urban waste water treatment plants to European surface waters are:

  1. Percentage of national population connected to waste water treatment
  2. Percentage of national population connected to tertiary waste water treatment


Percentage of national population connected to waste water treatment

About 80% of the population is connected to waste water treatment in Northern and Southern European countries. The connection rate in Central European countries is even higher, and exceeds 90%. On the basis of data reported in 2010, about 67% of total population is connected to wastewater treatment in the countries of Eastern Europe. Average connection rate in South-East Europe (Turkey, Bulgaria and Romania) is about 40%. About a quarter of population in South Eastern countries is connected to collecting systems without treatment. For the remaining countries the value of percentage of population connected to collecting systems without treatment ranges from 1,5 to 5,6.

Percentage of national population connected to tertiary waste water treatment

More than 70% of the population in Northern and Central Europe is connected to a wastewater treatment plant that implements tertiary treatment, substantially removing nutrients and organic matter. Wastewater generated by nearly half of the population in Southern and Eastern Europe receives tertiary treatment. This represents about 30% increase over last 10 years. In South-Eastern Europe the percentage of population connected to treatment plants with tertiary treatment is low (less that 9%), with 21% of the population of the region being connected to secondary treatment.

Timetable for the compliance with the UWWT Directive varies for EU15  and for new EU Member States (EU12). For Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal, Spain, Sweden and UK the latest date to fully comply with the Directive was 31/12/2005. For the new Member States in Central and Eastern Europe and in the Mediterranean, staged transitional periods have been set within the Accession Treaties; In principle these transitional periods do not exceed the year 2015; only in Romania, smaller agglomerations (with less than 10,000 p.e.) have to comply with the Directive by the end of 2018.

Specific regional assessment

Northern Europe (Fig. 2): The connection rate is around 80% in Norway, Sweden and Finland and, in the case of Finland, treatment is entirely at a tertiary level. In Norway, however, about a quarter of those connected receive primary treatment only. In Iceland waste water from about 30% of the population is collected in collecting systems, but is not treated, whilst the majority of Icelandic population connected to waste water treatment (about 50%) receives primary treatment. 

Central Europe (Fig. 3): Central Europe has one of the with highest overall connection rates in Europe and in Germany, Denmark, Switzerland, Austria and the Netherlands the rate of population connected to tertiary treatment ranges between 77-96%.
Connection rate to tertiary treatment is about 60% in Belgium. On the other hand Belgium reported the highest percentage of population connected to collecting systems without treatment (17%) among the Central counties.
England and Wales and Scotland report connection rates to tertiary treatment of about 40%, whilst in Ireland the figure is considerably lower at 12%. Secondary treatment in Ireland, however, increased considerably (more than three times) between 2001 and 2005. Percentage of population connected to collecting systems without treatment (11%) is also relatively high in Ireland in comparison to other Central countries. Connection rate to tertiary treatment is relatively low also in Luxembourg ( 22%).

Southern Europe (Fig. 4): The overall rate of population connected to wastewater treatment ranges from 13% to 94% in the countries of Southern Europe, being highest in Italy(94%), Spain (92%) and Greece (88%) and lowest in Malta (13%).Tertiary treatment occurs most often in Italy, Greece with rates around 80%. Spain and France reported connection rate to tertiary treatment 51% and 42% respectively. In other countries of the region the percentage of population connected to tertiary treatment is lower than 20%. Moreover, Malta reported that more than 50% of population is connected to collecting systems without treatment.

Eastern Europe (Fig. 5): The overall rate of population connected to wastewater treatment ranges from 52 to 81% in countries of Eastern Europe. Percentage of national population connected to collecting systems without treatment does not exceed 10% in Eastern countries. About 60% of population in the Czech Republic and Estonia is connected to tertiary treatment. Poland and Lithuania reported connection rate to tertiary treatment about 50%. In Latvia, the rate of connection to tertiary treatment is lower, about 40% whilst in Hungary and Slovenia only about a quarter of the national population is connected to tertiary treatment. For Slovakia there is no detailed information on treatment type available in Joint Questionnaire, however according to the data reported under the UWWTD for the reference year 2008 about 16% of total load generated in agglomerations larger than 2000 p.e. receives tertiary treatment and 69,7% of total load is treated in plants equipped with secondary treatment.

South-Eastern Europe (Fig. 6):  The rate of population connected to waste water treatment plants ranges from 29 to 46% in countries of South-Eastern Europe. Secondary or primary treatment prevails. Some tertiary treatment is applied in Turkey (12%).
About a quarter of population of Bulgaria and Turkey is connected to collecting systems without treatment. In Romania it is a bit less, 14%.

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?

Type of waste water treatment in EU big cities (agglomerations of more than 150 000 p.e.) expressed as % of total generated load treated, situation on 31st December 2009/2010

Note: The pie-chart summarizes 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. In total 640 big cities and big dischargers was reported, however complete data on waste water pathways was available only for 586.

Data source:
Downloads and more info

Specific assessment

Figure 7 summarizes the type of treatment applied in the wastewater treatment plants of 586 big cities/big dischargers with (250,2 mil. p.e.) reported in 2011 by the Member States. Five big cities reported no waste water treatment at all: 1 in Portugal , 1 in the United Kingdom and  3 in Italy.  Another seven had only primary treatment: 2 in Portugal, 1 in Spain, 2 in France and 2 in Romania. (deadline for compliance has expired in all above mentioned cases except for Romania)

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

2011 1.4.2 (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