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1 European Commission ESTAT 'RF::$ 2ULJLQDOLQ(1 3RLQW$RIWKHDJHQGD :DWHU'LVFKDUJHV 5RGULJR-LOLEHUWR7$8DQG/DUV.QXGVHQ9., Meeting of the Task Force on Water Statistics $GKRFJURXSRQZDVWHZDWHUWUHDWPHQWVOXGJHGLVSRVDODQGGLVFKDUJHV 0HHWLQJRIDQG)HEUXDU\ 6WDWLVWLFV1HWKHUODQGV&%69RRUEXUJ

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3 In the context of the Eurostat project Towards Environmental Pressure Indices for the EU (TEPI), 10 pressure indicators, of which six are operational, have been defined for each of the ten environmental policy fields laid down in the EU s Fifth Environmental Action Programme. These 60 operational indicators have been presented in the report Towards Environmental Pressure Indicators for the EU, first edition The indicators have been developed further and/or have been updated in the second year of the project. The data and methodologies for the five pressure indicators for water discharges to inland waters and to marine areas are explained in this document. :3(0,66,2162)1875,(17672,1/$1':$7(56 'HILQLWLRQ The indicator is defined as the average annual load of nitrogen and phosphorous from land sources (households and economic sectors) discharged into aquatic ecosystems. The indicator is expressed in tonnes per year or kg/hectare/year, reported separately for N and P. The indicator consists of emissions of nutrients from households, agriculture and industry. 0HWKRGRORJ\ $ (PLVVLRQVIURPKRXVHKROGV Household emissions are estimated using the following data: Population connected to treatment plants, by type of treatment (primary, secondary, advanced), and not connected to treatment plants. Nitrogen and phosphorus emission coefficients (kg N/inhabitant and kg P/inhabitant). Efficiency of the treatment plants. Total emissions before treatment are obtained multiplying the national population by the emission factor. These emissions are reduced taking into account the percentage of population connected to each type of treatment and the treatment efficiency. Data on the percentage of population connected to each type of treatment plant are available at the European Union level from the Eurostat/OECD Joint Questionnaire, and are included in ENVSTAT database (Eurostat). There are data available from 1970 to 1996 (data for 1997 is only available for Greece). Some data gaps in ENVSTAT database have been filled in with data from national sources and several publications. Average emission factors have been obtained from several information sources (Oslo and Paris Convention, Baltic Sea, Environment DG's reports, national sources, etc.). As the consumption of phosphate-free detergent has increased along the time series, a decreasing phosphate emission factor has been used in indicator calculation. WW/00/7A P. 3

4 Emission factors NJ\HDU 1LWURJHQ(PLVVLRQ )DFWRU 3KRVSKRUXV(PLVVLRQ )DFWRU Data on actual treatment efficiency are scarce, therefore the indicator has been calculated using the theoretical treatment efficiency (engineering data) included in the table below: Theoretical treatment efficiency Type of Treatment Primary Secondary Tertiary Nitrogen Removal Phosphorus Removal The engineering data used in estimations reflect the potential efficiency in pollution removal. As these efficiencies are average data, Member States with efficiencies higher than the average have lower actual emissions than those estimated. % (PLVVLRQVIURPDJULFXOWXUH Potential emissions from agriculture are included by means of the soil surface nitrogen balance, calculated by Eurostat. This balance takes into account the inputs of mineral nitrogen and nitrogen of animal origin, input from biological nitrogen fixation and atmospheric deposition, uptake by crops, and estimations on grass consumed based on fodder requirements. The data considered for indicator calculation is the nitrogen surplus by hectare of utilised agricultural land. The available data series correspond to 1990, 1993 and & (PLVVLRQVIURPLQGXVWULHV Discharge of nitrogen and phosphorous from industries into aquatic ecosystems takes place either directly or through public sewer systems. The discharges usually take the form of wastewater, process water and also, in some cases, of surface run-off water. Direct discharge can be in the form of untreated wastewater or wastewater after different types and degrees of treatment while discharge into public sewer system normally will be in the form of untreated or pre-treated wastewater and only in some rare cases as wastewater after advanced treatment. In the public sewer system the industrial wastewater will be mixed with household wastewater, infiltrated ground water and rainwater run-off, and the mixed wastewater can either be discharged into aquatic ecosystems without treatment or be let to a public wastewater treatment plant before final discharge. In summary, there are several ways whereby industrial wastewater can WW/00/7A P. 4

5 be discharged into aquatic ecosystems, and each way will have a specific impact on the contained nitrogen and phosphorous compounds. Some knowledge is available on the industrial load of municipal wastewater treatment plants. Meanwhile, it is quite complicated to determine or estimate the degree whereby nutrients originating from industrial discharges are removed in these plants. This requires beyond knowledge of the load also knowledge of the compositions of the specific nitrogen and phosphorous compounds within the wastewater. In cases where the nitrogen and phosphorous are bound to an organic fraction, also knowledge of the specific degradation in the treatment plants are required. As a consequence of these limitations, it has been decided to apply a more limited operational definition direct emissions of nutrients from industries into aquatic ecosystems. It is realised that this definition only includes a fraction of the total emission of nutrients from industries. Through many industries are connected to public wastewater treatment plants a large part of the total discharges still take place directly from the industries. The direct emissions of nutrients have been estimated as collected data from national inventories and other sources divided by the population in the individual Member States. The unit of measurement has been decided in order to be able to compare the emissions from the different Member States. However, it is realised that this method of measurement will reflect the industrial structure and the economical industrial activities in a given country to larger extent than environmental issues. Meanwhile, No other suitable unit of measurement has been found at present.,w KDV EHHQ IRXQG WKDW DJJUHJDWHG QDWLRQDO GDWD RQ GLUHFW LQGXVWULDO GLVFKDUJHV DUH SHUIRUPHG LQ RQO\ D OLPLWHG QXPEHU RI FRXQWULHV $YDLODEOH GDWD LV W\SLFDOO\ LQ DQ XQWUHDWHGIRUPQRWVXLWDEOHIRUGLUHFWSXEOLFDWLRQ :3(0,66,2162)25*$1,&0$77(5$6%2'72,1/$1':$7(56 'HILQLWLRQ The indicator is defined as the quantity of organic matter discharged by human activities measured in terms of BOD (BOD tonnes/year). In the applied definition the emissions are reported separately for households and industries, and expressed in kg/capita. The indicator consists of emissions of nutrients from households and industry. The emissions of organic matter from households and industries are described separately due to different methodological approaches, use of different databases as well as differences in quality and quantities of the discharges. 0HWKRGRORJ\ $ +RXVHKROGVHPLVVLRQV The emissions from households have been calculated using the following data: Population connected to treatment plants, by type of treatment (primary, secondary, advanced), and not connected to treatment plants. Emission factors of BOD per inhabitant. BOD removal efficiency by each type of treatment. WW/00/7A P. 5

6 Total emissions before treatment are obtained multiplying the national population by the emission factor. These emissions are reduced taking into account the percentage of population connected to each type of treatment and the treatment efficiency. Data on the percentage of population connected to each type of treatment plant are available at the European Union level from the Eurostat/OECD Joint Questionnaire, and included in ENVSTAT database (Eurostat). There are data available from 1970 to 1996 (data for 1997 are only available for Greece). Some data gaps in ENVSTAT database have been filled with data from national sources and several publications. Considering that emission factors from different data sources are not comparable and there are no available data for some countries, it has been decided to calculate the estimations with the same emission factor for all the Member States. This factor is 60 gr. BOD/person and day. Data on actual treatment efficiency are scarce, therefore the indicator has been calculated using the theoretical treatment efficiency (engineering data) included in the table below: Theoretical treatment efficiency Type of Treatment Primary Secondary Tertiary BOD Removal The engineering data used in estimations reflect the potential efficiency in pollution removal. As these efficiencies are average data, Member States with efficiencies higher than the average have lower actual emissions than those estimated. % (PLVVLRQVIURPLQGXVWULHV By the selected methodological approach applied for this indicator, only a limit number of industrial branches have been considered. The operational definition used can therefore be described as the quantity of organic matter discharged by selected industrial branches measured in terms of BOD. The methodology developed by the World Bank NIPR Group was adopted. In this methodology it was found that sectoral intensities are always exponentially distributed, with a few highly intensive sectors and many with very low intensities. The conclusion of this finding was that pollution projections always should be done with the most disaggregated data available. Further, it was revealed that regarding industrial water pollution within specified sectors, BOD emission/labour ratios are approximately constant across countries at all income levels of economic development. That is, developing economies generate much more pollution per unit of output than developed countries, but they also employ much more labour per unit of output, and in the same ratio. Thus, emission coefficients related to labour are expected to be more reliable than coefficients related to output when comparing total sectoral emissions across countries. WW/00/7A P. 6

7 The emission coefficients reported by the World Bank are all 1987 US data at the ISIC4-digit level. The coefficients are based on environmental and economic information from approximately 200,000 factories in all regions of the United States. In most cases translation of ISIC codes into NACE codes was found to be quite simple. Transferring the IPPS emission coefficients (US-data) to Europe impose limitations to applicability and the data should therefore be used with care. However, the IPPS data sets are so far the only data available with emission coefficients at a highly disaggregated level. Altogether, 68 emission coefficients on different industries were obtained. Data on employment in the different industrial sub-groups and countries was made available from Eurostat. Year 1993 was used as reference year for the calculations. In some cases only employment data was available for 1992 or In these cases this data were used as the best alternative. In general the methodology applied presents the most disaggregated level, and it is possible to extract the contributions from each industrial subgroup included. However, it was found suitable only to perform the sectoral breakdown into 9 main industrial groups. The result obtained should be used with great care, as it only accounts for 0,9 mill tonnes BOD (total EU), which is less than 50% of the expected total industrial emissions in the Member States. 7;,1'(;2)+($9<0(7$/(0,66,2172:$7(5& Heavy Metals are totally persistent and all amounts emitted to water will accumulate in water, sediments and, when applicable also in sewage sludge. Many heavy metals are toxic and an accumulation in these media is, consequently, not sustainable. 'HILQLWLRQ According to the original PIP definition, heavy metals are described as metals with an environmental interest - e.g. mercury, cadmium, and lead - with few exceptions - HJ aluminium. By giving them index, they can be handled in clusters according to sources and emission patterns. The unit of measurement was given as tonne per year. In the first year of the TEPI project the indicator was limited to development of emission coefficients from households and evaluation of the fate of the metals in different municipal wastewater treatment plants. The estimates of the emitted amount of metals were aggregated into one index by use of an eco-toxicity-weighting scheme. The weighting scheme was developed by use of reference values for sediment and water adopted from OSPAR. No time series were produced, as there was a lack of yearly data on emission coefficients from households in most countries. Identification of reliable data on emissions and/or emission coefficients from different types of industries and emissions from other sectors e.g. agriculture and energy was found to be very difficult. As an alternative, a top down approach was used by expressing the heavy metal emissions as direct and riverine inputs to the coastal zones. The emissions were estimated by use of data presented by various HELCOM and OSPACOM reports, and it was possible to produce time series for 1990 to WW/00/7A P. 7

8 However, this approach on development of the indicator is not particularly satisfying compared to the original PIP definition. Considering the difficulties in obtaining reliable data on heavy metal emissions to water it is proposed in this second phase of the study to work on a very limited operational definition of the indicator: emission of mercury, cadmium and lead to water from selected sources. The unit of measurement is Arsenic Toxicity Equivalents (As-EEQ) per annum. 0HWKRGRORJ\ Two approaches have been used for development of a methodology for the indicator: Development of time-dependent emissions coefficients from households and detailed evaluation on the fate of the metals in different types of municipal wastewater treatment plants Development of overall aggregated estimates of heavy metal emission to water, in order to point out the most important sources in different countries The unit of measurement is kept as developed for the first year TEPI report. This unit of measurement is based on a weighting scheme for the metal considered which is used to produce a weighted summarisation index. The weighting applied is based on roughly estimated and tentative reference values for trace metals in sediment and water proposed by OSPAR (1994). Finally, it is suggested to normalise the factors relative to arsenic. Arsenic is regarded as a potentially very hazardous metal and is often used for normalisation, and thereby given the weighting factor 1. In using reference values of both sediments and water it is suggested that equal weighting be applied. Regarding emission coefficients to water of the considered heavy metals from households the methodology is based on collecting as many reliable year-specific data as possible and from as many countries as possible. In comparing the collected data different mathematical methods are used in order to develop possible trends and possible differences between the individual countries. Regarding emission from wastewater treatment plants, a model was developed based on the fraction of population connected to various types of treatment plants. Generally four treatment situations were considered: No connection to treatment plants and connection to primary, biological or advanced treatment facilities. Each of the three treatment options will have a different impact on the removal of heavy metals from the liquid fraction of the wastewater as presented in the table below. The data sources applied were from the Eurostat/OECD Questionnaire, and are included in ENVSTAT s database. 0(',6&+$5*(62)+($9<0(7$/6720$5,1(:$7(56 2SHUDWLRQDOGHILQLWLRQ The riverine and direct inputs as well as the total (dry and wet) deposition of heavy metals (Copper, Lead, Mercury, Cadmium and Zinc) into the coastal zone and marine environment. The results are expressed in terms of Tonnes Arsenic Eco-toxicity Equivalents (As-EEQ). WW/00/7A P. 8

9 0HWKRGRORJ\ It is suggested to base the methodology on specific international reports on ecotoxicity as the main data sources in order to set up a viable weighting factor system. The group of heavy metals considered is not well defined and includes metals which are highly hazardous to man and the environment due to their toxicological properties, e.g.,. mercury, cadmium and lead as well as metals with a lower toxicological potential, e.g,. zinc and copper. Because of differences in environmental properties and exposure routes the index should be used with caution. The methodology applied includes the following suggestions: Development of an index based on a weighting summarisation of the considered metals To base the weighting scheme among the metals on roughly estimated and tentative reference values for trace metals for sediment and water proposed by OSPAR (1994) for the marine environment To normalise the weighting factors relative to arsenic (= apply the weighting factor of 1for Arsenic) To apply an equal weighting on the ecotoxicity reference values of both sediments and water The data on heavy metal emission to coastal zones, published in HELCOM Compilations (1985, 1990, 1995) and in the OSPAR Summary Report of the Comprehensive Study on Riverine Inputs and Direct Discharges in (1998) were used to calculate national emissions from the Member States. The references include data sets on direct and riverine inputs of heavy metals to the marine environment specified by different sea areas. It was therefore necessary to reorganise the data from references to sea areas to references to countries in order to calculate the contributions from the individual countries. As a tool for data management, a database was developed covering riverine and direct inputs of heavy metals from individual countries by year, receiving sub region, type and amount of water input (direct or riverine) as well as type and amount of heavy metals in the water. The database covers more than 5,000 data sets and there is a representation of altogether 11 EU Member States covering the marine environment and coastal areas from Gibraltar to the Gulf of Bothnia. Data on heavy metal deposition (wet and dry) into marine areas was obtained from different reports published by OSPAR, HELCOM, UNEP, and EMEP. However, it has only been possible to obtain satisfying time series for the Baltic Sea and some single standing data from the North Sea and NW Mediterranean. 0(2,/32//87,21$7&2$67$1'$76($ 'HILQLWLRQ The original PIP definition of the indicator is total accidental, licensed and illegal disposal of mineral oil to the coastal and marine environment. The unit of measurement is metric tonnes per annum. WW/00/7A P. 9

10 In the first year s study of the TEPI project it was only possible to present a very rough picture of the total amount of oil disposal to the marine environment and a presentation was only possible with reference to specific sea areas. Many sources of marine oil pollution have been identified and most of these are not monitored on a regularly basis. Further it was found that oil spills at sea are by far the most important source for the indicator and will dominate the data presentation especially when oil tankers are wrecked near the coast in one of the Member States. Based on findings in the first year of study, it is recommended to develop an alternative operational definition of the indicator. A proposal for an operational definition could include a division of the indicator into two sections: Oil lost at sea by spills (legal as well as illegal) from shipping Oil disposal to marine environments by other significant sources than shipping. Further, it is suggested to maintain the unit of measurement in metric tonnes per year. By other sources than shipping focus should primarily be on oil lost by offshore activities and oil discharged by coastal refineries. Riverine inputs of oil as well as directs inputs of oil from coastal industries and deposition from the atmosphere are other important sources. However, in these cases no aggregated and reliable data seems to be available at present. In favour of the operational definition is also the observation that accidental oil spills and/or illegal oil disposal at sea receives much attention from the press (polluted coast lines, dead birds, etc.) rather than other types of oil disposal at sea. 0HWKRGRORJ\ The applied methodology included the following steps: 1. Collection of data on recorded oil spills in the individual Member States 2. Collection of data on oil discharges from offshore activities and from refineries as well as production figures 3. Development of emission coefficients from offshore activities and refineries based on an EPIS approach (emission per product unit). This seems to be necessary as oil disposal from these activities are recorded only every three to five year and not in all Member States 4. Calculation of total oil disposal from offshore activities and refineries based on emission coefficients in order to produce time series 5. Evaluation of obtained calculation results on oil disposal by offshore activities and refineries compared to published and available data 6. Aggregation of total oil disposal from offshore activities and refineries into one indicator Data on oil discharges was obtained from ITOPF, CONCAVE and OSPAR, while data on oil production offshore and at refineries was obtained from Eurostat's SERINE database. WW/00/7A P. 10