Personal tools


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 - outlook EEA / Urban waste water treatment - outlook EEA (Outlook 047) - Assessment published Jun 2007

Urban waste water treatment - outlook EEA (Outlook 047) - Assessment published Jun 2007

Indicator Assessmentexpired Created 08 Jan 2007 Published 08 Jun 2007 Last modified 12 Nov 2013, 09:27 AM
This content has been archived on 12 Nov 2013, reason: Content not regularly updated
Required information is not filled in: Information about the starting date of the publishing schedule is missing.

Generic metadata


Environmental scenarios Environmental scenarios (Primary topic)

Water Water

waste water | forward looking indicators | nitrogen | phosphorus
DPSIR: Response
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
Indicator codes
  • Outlook 047
Geographic coverage:
Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Luxembourg, Netherlands, Poland, Portugal, Slovenia, Spain, Sweden

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

Key messages

Assessment is created in 2007

By increasing the connection rate of the European population and the use of tertiary treatment, implementation of the UWWT directive is expected to make it possible to increase the amount of wastewater treated while reducing total discharges of nutrients.

The diverse situation in European countries regarding wastewater treatment systems is a challenge to the implementation of EU directives.

Diffuse sources of nutrients (e.g. agriculture) are expected to become prime issues to address as implementation of directives targeted at point sources results in significant reductions in their environmental impact (e.g. eutrophication).

Discharges of nitrogen and phosphorous from wastewater treatment plants

Note: N/A

Data source:

EEA European Topic Centre on Water: National Environmental Research Institute + International Office for Water + WRc, 2003-2004. Dataset: ETC/WTR model.

Downloads and more info

Key assessment

Industrial production and household consumption increased at a rapid rate during the last century, producing larger amounts of wastewater. The extent to which this is discharged into surface waters depends on the sewage collection and treatment facilities available, as well as on the content of the items produced or consumed (e.g. phosphorus in detergents). In Europe most phosphorus loading of surface waters is attributable to discharges from point sources (in particular municipal sewage and industrial effluents), while nitrogen loading comes mainly from the use of nitrogen fertilisers and manure in agriculture.

The central piece of legislation for this outlook is the Urban Waste Water Treatment Directive (91/271/EEC) (148). It is a key EU water policy, which aims at protecting the environment from the adverse effects of urban wastewater discharges. The directive sets minimum standards for the collection, treatment and disposal of wastewater that depend on the size of the agglomeration, and the type and sensitivity of the receiving waters. In general terms, the directive has to be fully implemented in the EU-15 countries by the end of 2005 and in the New-10 in the 2008-2015 period; the majority of the urban population will then be connected to tertiary or secondary treatment.

Specific policy question: Is the Urban Waste Water Treatment Directive (91/271/ECC) being implemented in Member States?

Current and projected levels of wastewater treatment in Europe

Note: N/A

Data source:

EEA European Topic Centre on Water: National Environmental Research Institute + International Office for Water + WRc, 2003-2004. Dataset: ETC/WTR model.

Downloads and more info

Specific assessment

Since many EU-15 countries have delayed implementing the UWWT directive, and the New-10 have diverse transition periods, this outlook reports the expected discharges of nutrients after the implementation of the directive rather than by a specific date. There are many requirements and deadlines for implementation of the directive, and there is significant uncertainty regarding its final implementation.

Implementation of the UWWT directive is expected to lead to the following developments (see Figures 1 and 2) (149):

  • A dramatic shift towards tertiary treatment is expected in the New-5 (Estonia, Czech Republic, Poland, Hungary and Slovenia) and Belgium and Luxembourg (Group 2), at the expense of primary and secondary treatment and significant levels of discharge without treatment. In the New-5, these improvements are expected to be accompanied by an increase in the connection of the population to wastewater treatment plants from 57 % to 70 %. For the Group 3 countries and the United Kingdom, in all of which a relatively low proportion of the territory is designated as sensitive area, the future development of wastewater treatment is expected to be characterised by an increasing connection rate (from 67 % to 80 %) and an enhanced diffusion of secondary treatment. Finally, only minor changes in the level and type of wastewater treatment are expected in Group 1 countries, since they already almost (i.e. in terms of level and type of wastewater treatment) and have a very limited amount treated only in primary facilities or discharged without treatment.
  • Considerable reductions in nutrient discharges are expected in countries that experience a dramatic increase in tertiary treatment. Belgium and Luxembourg are projected to reduce their total discharges of nitrogen and phosphorous by 40 % and 80 % respectively. In the New-5, discharges are projected to decrease from 3 to 2.3 kg N/person/year (a 24 % reduction), and 0.4 to 0.15 kg P (62 %). In contrast, total discharges in Group 3 countries are expected to increase since the percentage of the population connected to UWWT plants will increase significantly while tertiary treatment will remain limited: nitrogen and phosphorous discharges are projected to increase by about 14 %, which, compared with a 29 % increase in the connected population, leads to a slight decrease of nutrient discharges per capita. Finally, discharges are expected to remain nearly unchanged in countries that have already almost achieved the directive's requirements (Group 1).
  • Overall nitrogen and phosphorus discharges in countries with high levels of tertiary treatment are expected to be about 2.3 kg N/person/yr and 0.1 kg P. Countries that plan to rely essentially on secondary treatment are expected to have significantly higher discharges, in particular for phosphorous, by an estimated factor of three.
  • At the country level, data and information on wastewater treatment and population distribution in terms of size of agglomeration are limited and heterogeneous, hence very difficult to compile into a European overview. There is also some uncertainty about the detailed national implementation of the UWWTdirective (150). As a consequence, the projections reported here are subject to some uncertainty, and might conflict with national assessments.

By increasing the connection rate of the European population, the UWWT directive would in principle increase discharges of nutrients from UWWT plants; however, the increasing use of tertiary treatment that should result would make it possible to increase the amount of wastewater treated and achieve an overall decrease in discharges of nutrients. The net benefit to the environment, in terms of reduced discharges leading to less eutrophication, is therefore considerable since wastewater is expected to be more systematically treated in future and in a more efficient way (151).

Data sources

  • No datasets have been specified.

More information about this indicator

See this indicator specification for more details.

Contacts and ownership

EEA Contact Info

Anita Pirc Velkavrh


EEA Management Plan

2010 (note: EEA internal system)


European Environment Agency (EEA)
Kongens Nytorv 6
1050 Copenhagen K
Phone: +45 3336 7100