Indicator Fact Sheet (WEU16) Urban waste water treatment

Transcription

1 Indicator Fact Sheet (WEU16) Urban waste water treatment Author: Benoit Fribourg-Blanc, IOW EEA project manager: Niels Thyssen version Key message Wastewater treatment in all parts of Europe has improved significantly since the 1980s. In several countries in north-western Europe there has been a marked increase in the population connected to tertiary waste water treatment in the 19 resulting in marked reductions in phosphorus and nitrogen discharges. However the percentage of population connected to waste water treatment is relatively low in southern Europe and in the Accession countries. Figure 1: Changes in wastewater treatment in regions of Europe between 1980s and late Tertiary Secondary Primary percent of population Late Late Late Late Nordic (4) Central (8) South (2) AC (4) Notes: Only countries with data from all periods included, the number of countries in parentheses. Nordic: Iceland, Norway, Sweden, Finland. Central EEA: Austria, Ireland, United Kingdom, Luxembourg, Netherlands, Germany, Denmark, Switzerland. Southern: Greece, Spain AC: Bulgaria, Estonia, Hungary, Poland Sources: EEA ETC/WTR based on Member States data reported to OECD / EUROSTAT Joint Questionnaire

2 Results and assessment Policy relevance: Wastewater from households and industry represent a significant pressure on the water environment. The Urban Wastewater Treatment Directive (UWWT) prescribes the level of treatment required before discharge. The indicator describes a response to reduce the pollution load arising from wastewater, that is, the amount of the population connected to public wastewater treatment plants. Policy context: The Urban Wastewater Treatment Directive (UWWTD) requires Member States to provide all agglomerations of more than population equivalents (p.e.) with collecting systems. Secondary treatment (i.e. biological treatment) must be provided for all agglomerations of more than p.e. discharging into fresh waters and estuaries and for all agglomerations of more than p.e. discharging into coastal waters. In the 14 Member States (no data from Italy), there are agglomerations with more than p.e., equivalent to organic matter from 424 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. Environmental context: Primary treatment (mechanical treatment technology) removes part of the suspended solids, while secondary treatment (biological treatment) uses aerobic or anaerobic micro-organisms to decompose most of the organic matter and retain some of the nutrients (around %). Tertiary treatment (or advanced treatment technology) generally includes phosphorus retention and in some cases nitrogen removal. Primary treatment alone will remove no ammonium whereas secondary (biological) treatment will remove around 75%. The data on the percentage of population connected to the different types of wastewater treatment plants can be used to illustrate trends in wastewater treatment. As well as containing organic matter and nutrients, wastewater can also contain hazardous substances. The level of treatment of these hazardous substances before discharge and the sensitivity of the receiving waters will affect their impact on the aquatic ecosystem % of Europe s population was urban in 1999 (417 million people). Assessing the population connected to urban wastewater treatment plants gives a clear overview of the pressure exerted on the receiving waters. EU Member States have to identify water bodies as sensitive areas in accordance with the criteria of the Directive (eutrophication). In sensitive areas and catchments of sensitive areas, Member States have to provide more advanced treatment of wastewater with nutrient removal. Assessment: Over the last twenty years, marked changes have occurred in the proportion of the population connected to wastewater treatment as well as in the wastewater treatment technology involved. In northern countries most of the population are today connected to wastewater treatment plants with tertiary treatment, which efficiently removes nutrients and organic matter from the wastewater. In the central EEA countries more than half of the wastewater is treated by tertiary treatment, which removes most of the organic matter and the ammonia. Southern countries and the Accession countries only have around half of the population connected to wastewater treatment plants at the moment. 30 to 40 % of the population are connected to secondary or tertiary treatment

3 Sub-indicators Key message Only 2 EU countries were close to conforming with the requirements of the UWWT Directive regarding their large agglomerations discharging into sensitive areas by the end of 1998, and 8 countries were far from conformity. Many of the 527 cities with population equivalents greater than did not have a sufficient standard of treatment by the end of 1998 to meet the objectives of the UWWT Directive. Figure 2: Conformity to article 5 (paragraph 2) of UWWT Directive by 31 December 1998 (tertiary treatment for agglomeration with population equivalent greater than discharging into sensitive areas). % of total load % load in sensitive area conform % load in sensitive area not conform BE DK DE GR ES FR IE IT LU NL AT PT FI SE UK Notes: Of the 13 EU Member States which provided sufficient information only 2 (Denmark and Austria) were considered by the European Commission to be almost in conformity with the Directive s requirements. All other Member States were considered not to be in conformity. Source: DGENV 2002 Figure 3: Levels of urban wastewater treatment in large cities in the EU, 1998 Treatment in large European cities Secondary plus full tertiary treatment Full secondary and full secondary with incomplete tertiary treatment Incomplete secondary treatment or primary treatment no treatment no information Notes: A large number of 527 cities with population equivalent more than did not have a sufficient standard of treatment by end of 1998 to meet the objectives of the UWWT Directive. 37 had no treatment at all including Brussels, Milan and Athens. Germany and France did not provide any information on their 190 cities. Since 1998 plans have been put into place to improve the situation in those cities with no treatment and incomplete treatment. % load = organic load No data on loads conforming from DE, FR, LU and NL Source: DGENV

4 Assessment for the sub-indicator The Urban Waste Water Treatment Directive (UWWTD) requires Member States to identify water bodies as sensitive areas in accordance with defined criteria such as the risk of eutrophication occurring. Member States were required to ensure that wastewater treatment facilities with tertiary treatment were in operation for all agglomerations with a population equivalent greater than and whose effluent was being discharged into a sensitive area or its catchment by 31 December 1998 and at least secondary treatment by 31 December 2000 for those discharging into normal waters. The European Commission has published a report on Member States conformity with this requirement. However, by the end of 1998 many of the 527 cities with population equivalents of greater than did not have a sufficient standard of treatment. 37 agglomerations had no treatment at all, including Brussels, Milan and Porto, while a total of 57 agglomerations were discharging a large part of their effluents untreated or had a clearly insufficient level of treatment in place, including Aberdeen, Athens, Barcelona, Dublin, Liege, Marseille and Florence. The situation is, however, generally improving and some of these cities made the necessary investment in , or plan to complete work soon. References EUROSTAT / OECD Joint questionnaire 2000 UWWTD (91/271/EEC) 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 regarding wastewater treatment in major cities, verification of the identification of sensitive areas by the Commission (EC 2002) consultation November 2002 OECD ENVIRONMENTAL PERFORMANCE REVIEW, UNECE report National Statistical offices and SoE reports ( consultation November 2002 Data Spreadsheets: 03-UWWTD-v4.xls 02-WWTP-v2.xls Table 1: Waste water treatment in the EECCA countries Armenia Azerbaijan The sewerage infrastructure was well developed in the past, but its present status is critical. There are sewerage systems in all towns but 60 to 80 % of waste waters, of which 75 % in Yerevan, are collected in km of old and worn out pipes. 60 % of these pipes are older than 20 years. 18 main treatment plants exist with a total designed capacity of m3/day, but the plants may no longer be in operation or only operate primary treatment. Almost no collective infrastructure for waste water exists in rural areas. The industries discharge to municipal sewers or directly to surface water bodies. In 1995, 841 million m3 of wastewaters (57 %) was treated in biological treatment plants, which were overloaded and lacking the means to treat toxic waste, and 29 % were treated in mechanical treatment plants. Most waste water is produced by industries such as cotton cleaning, cotton oil production, fish curing and grape processing, and is discharged untreated to the municipal sewers

5 Due to neighbourhood relationship problems with Armenia, some deliberate river pollutions have occurred. Belarus 46 % of the waste water is treated with biological treatment (882 million m3 in 1993). Between 1990 and 1995 the discharge of waste water fell by 32 %, which led to an equivalent decrease in the discharge of untreated waste water. Untreated industrial and municipal waste waters are treated together. The treatment plants are overloaded and do not have the means to treat toxic waste. A heavy polluter is a potash mine that has recently improved its treatment plant. A State programme was given the objective of achieving proper treatment systems for all towns with more than inhabitants by Georgia 60 % of waste water is domestic, 55.7% of the population live in urban areas and 45 % of urban areas have a sewerage system in operation. In 1994, 13 % of domestic and industrial waste water was treated, whereas in 1985, 45 % was treated. Most waste water treatment plants are not operating or only at a very low level of efficiency. In Tbilisi in 2000, 80.4% of population were connected to sewerage systems and 20 % of waste water was treated. Moldova About 53 % of the population and many industrial plants are connected to km of sewers and to 35 municipal wastewater treatment plant with a design capacity of million m3 to reach % abatement of BOD. Most villages discharge their waste water untreated. The connected industries are required to pre-treat and 50 industrial waste water treatment plants have been built. Most of these are not operated. In 1993, 60 % of the installations were in operation, some overloaded, especially by heavy metals from untreated industrial waste waters, the rest out of operation due to lack of maintenance or age. In 1994, 52 % of the 350 million m3 of waste water collected was sufficiently treated, 46 % only partly treated and 2 % untreated. Kazakhstan In 1993, total waste water produced amounted to 1.8 km³/year, of which 0.27 km³/year was treated. In 1998, 4.8 km³ was produced. The discharge of toxic waste has decreased. Collected waste water through extremely worn out networks is low at just 19 %. In the major cities (Almaty, Kokshetau) storm water is collected separately and directly discharged to surface waters. Waste water is collected in large sewers and treated at plants with good treatment efficiency (88.5 % for Almaty, 83 % for Kokshetau, but 30 to 60 % for Atyrau), then to specially prepared lakes. Kyrgyzstan Less than 50 % of settlements are equipped with waste water treatment plants that receive both municipal and industrial waste waters. 40 % of the waste water treatment plants in existence do not operate at all, 30 % do not meet the required standards, and the rest often only operate primary treatment. Industries often have pre-treatment installations but they are rarely operated. More than 90 % of the rural population are not connected to waste water treatment plants. The poor technical state, poor maintenance and overload of existing installations together with very low investment have led to concerns for the surface and groundwaters. Russian Federation About 55 % of the population are connected to public waste water treatment plants. All large cities have secondary treatment plants (except Murmansk, with only a primary treatment plant, and Vladivostok, with sewerage network but without treatment). Smaller towns mostly have only primary treatment facilities. Facilities providing tertiary treatment (chemical processes) represent 2 % of total waste water treatment capacity. Treatment efficiency is low: only 10.8% is treated to required standards. The poor condition of municipal waste water treatment plants and the high load of toxic waste from untreated industrial waste waters are the main reasons for this. However, progress has been made over the last five years: treated waste water has increased by 2.9 %. Waste water treatment facilities in Russia presently treat 20 km3 per year. Nearly 22 km3 of wastewater is discharged annually through the sewerage system: 17.4 km3 (76 %) is treated, of which 16.6 km3 (94 %) by biological treatment plants. Tajikistan Communal waste waters are treated with secondary treatment. Industries are treated in 300 outdated waste water treatment plants mainly with secondary treatment but with a 30 % abatement rate. Many rural settlements and some cities have no waste water purification facilities and hence all waste water is discharged directly. Turkmenistan In Turkmenistan only 44 % of the population are connected to sewerage systems. At present, none of treatment plants in Turkmenistan achieve the required parameters and most of them discharge waste water into desert depressions practically untreated. The centralised sewerage systems do not satisfy the current requirements. Ukraine: Waste water treatment is a major problem in Ukraine due to poor quality and inefficiency of waste water and sludge treatment. Bad technical state, poor maintenance and overload of existing installations have led to this. Over 60 % of the population are connected to km of sewers and to municipal waste water treatment plants with a total treatment capacity of 5.7 billion m3/year, mostly secondary treatment, but a majority of the villages discharge their waste water without treatment. In the Dnieper river basin, which serves as a source of drinking water for 30 million

6 people, only 25 % of the sewage is treated to a level that meets current hygiene standards. Uzbekistan Many cities have installations that only partially treat domestic sewage, but, due to obsolete equipment and technologies in many plants, the efficiency for municipal and industrial waste water is about 50 %. Sewage water and industrial water are usually treated together by mechanical and biological methods. Treated and partly treated sewage is discharged into surface water. 2.2billion m3/year of industrial waste water is discharged only partially treated. Meta data Technical information 1. Data source EUROSTAT / OECD Joint questionnaire 2000, theme 3 table demography (population data) and theme 8 table 4. UWWTD (591/271/ECC). 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, OECD ENVIRONMENTAL PERFORMANCE REVIEW, UNECE report, National Statistical offices and SoEs ( 2. Description of data: Data of population is extracted from a request to the EUROSTAT / OECD database called New-cronos expressed in capita. Percentage of population connected to wastewater treatment types: Distribution of treatment types, expressed as percent of population connected, per country. For the NIS countries the data on population come from the respective national statistical offices, and the wastewater information from international and national publications. 3. Geographical coverage: For this illustration, the whole EEA area is covered and the whole NIS countries but data are only available for a maximum of 21 out of the 31 countries for EEA area and 1 out of 10 countries for the NIS. 4. Temporal coverage: Data are available from 1970; they should be available since 1993 yearly for internal national reports, every two years for Member States reporting to the Commission and synthesis report by the Commission. 5. Methodology and frequency of data collection: A yearly survey has to be made by water policy authorities to control the conformity of MSTP discharges that should not exceed 25 mg/l of O2 for EU countries. 6. Methodology of data manipulation, including making early estimates : Average of percentages connected to each treatment type, weighted by total population in each country. For conformity : national figures for the 1998 report. For AC countries : the most recent figure of the period mentioned is used. For the NIS countries : the most recent figure available for each of the series is used Quality information 7. Strength and weakness (at data level): The treatment types are only coarse indications of the quality of purification. There are some variations in the definitions of different classes of treatment between countries. Not all countries provide data for all years, or have the same information level as regards the wastewater treatment plants situation. 8. Reliability, accuracy, robustness, uncertainty (at data level): Different definitions decrease the comparability of the data. Data are collected from national statistical offices. 9. Overall scoring (give 1 to 3 points: 1=no major problems, 3=major reservations): Relevancy: 1 Accuracy: 2 Comparability over time: 1 Comparability over space:

7 Further work required The data on the percentage of population connected to the different types of wastewater treatment plants are the only data which can be used to illustrate trends in waste water treatment. More detailed information on P and/or N removal would give a better indication of the quality of purification. Future reports of the Commission will provide more information on the implementation of UWWT Directive in Member States. Future improvements in the data collection process of EUROSTAT will improve the quality of information