water statistics, technical obstacles

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Wastewater generation treatment
statistics Reliable statistics Intersecretariat
Working Group on Environment Statistics Work
Session on Water Statistics (Vienna, 20-22 June
2005) Benoît FRIBOURG-BLANC
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Wastewater from generation to discharge Various
pathways
Source Lassainissement des grandes villes,
RNDE, France, 1998
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Wastewater from generation to discharge
Wastewater loading scheme

• 4 steps
• Water quantity and transfers
• pollution quantity and transfers (non
  conservative)
• Equipments and performance

Source Data Collection Manual for the
OECD/Eurostat Joint Questionnaire on Inland
Waters, Tables 1 7, June 2004
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Definitions for Wastewater Proposed sources
organisation
NACE/ISIC approach
Source Data Collection Manual for the
OECD/Eurostat Joint Questionnaire on Inland
Waters, Tables 1 7, June 2004
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Definitions for Wastewater Some characteristics
of sources

• Only the agent that emit the pollution (avoid
  double counting)
• Point, small point and diffuse sources
• A link with NACE/ISIC
• Process based vs Source based NOSE

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Definitions for Wastewater the collection systems

• The first part of the wastewater treatment
  system,
• Many equipments,
• Estimation of performance,
• Reduced to connection rate,
• Private part neglected,
• Population served vs connected.

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Definitions for Wastewater the treatment

• Definition / delimitation
• Primary, Secondary and Tertiary treatment (JQ
  design and real performance)
• Investment - working costs / pollution
  destruction - transfers

Source SANDRE-OIEau 1997
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Definitions for Wastewater the pollution

• the direct or indirect introduction, as a result
  of human activity, of substances or heat into the
  air, water or land which may be harmful to human
  health or the quality of aquatic ecosystems or
  terrestrial ecosystems directly depending on
  aquatic ecosystems, which result in damage to
  material property, or which impair or interfere
  with amenities and other legitimate uses of the
  environment. (EU Water Framework Directive)
• Parameters and substances
• Geographical and temporal
• Available classification systems (CAS, ELINCS,
  EINECS)

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data collection for Wastewater the raw data

• Temporal and geographical variations,
• High influence of processes and human activities,
• Multiple pathways
• Reliable monitoring (continuous, quality check)
• High cost of monitoring,
• ?combination of monitoring and calculating
• (formula, emission factors, models, experts)

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data collection for Wastewater data aggregation

• A wide use of thresholds reliable individual
  data,
• A need to complete the picture,
• A need to aggregate for international statistics,
• Geographical or temporal aggregation (frequency,
  quality),
• Wide use of all possible methods from monitoring
  to modelling

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Wastewater generation and discharge The main
conclusions

• Reliability is crucial for priority setting
• Completeness vs confidence
• shared terminology (definitions, data format,
  nomenclature)
• ?EN 10851997 wastewater treatment
• Not only monitoring but also design capacity,
  emission factors and other estimations.