COMMISSION STAFF WORKING DOCUMENT IMPACT ASSESSMENT Accompanying the document Proposal for a Directive of the European Parliament and of the Council concerning urban wastewater treatment (recast)
Date: 2022-10-26
Institutions: Directorate-General for Environment, European Commission
Subjects: industrial pollution, pollution control measures, public health, urban area, wastewater, water pollutant, water pollution, water protection, water treatment

EN 

  EN 

   EUROPEAN COMMISSION  Brussels, 26.10.2022  SWD(2022) 541 final  COMMISSION STAFF WORKING DOCUMENT  IMPACT ASSESSMENT  Accompanying the document Proposal for a Directive of the European Parliament and of the Council concerning urban wastewater treatment (recast) {COM(2022) 541 final} - {SEC(2022) 541 final} - {SWD(2022) 544 final}  
 
 
Table of contents 

1. 

INTRODUCTION: POLITICAL AND LEGAL CONTEXT ................................... 13 

2.  PROBLEM DEFINITION ........................................................................................ 15 

2.1 What are the problems and their drivers? ............................................................ 15 
2.1.1 Remaining pollution from urban sources – problem and drivers ............. 15 

2.1.1.1 Non-compliant agglomerations ..................................................................... 16 

2.1.1.2 Storm water overflow (SWO) and urban runoff ........................................... 17 

2.1.1.3 Individual appropriate systems (IAS) ........................................................... 18 

2.1.1.4 Small agglomerations .................................................................................... 18 

2.1.1.5 Remaining releases from Nitrogen and Phosphorus ..................................... 19 

2.1.1.6 Micro-pollutants and Micro-plastics ............................................................. 20 

2.1.1.7 Non domestic releases ................................................................................... 22 

2.1.2 Alignment with Green Deal, new societal challenges - problems and 
drivers ....................................................................................................................... 23 

2.1.2.1 Green House Gas emissions .......................................................................... 23 

2.1.2.2 Energy use ..................................................................................................... 23 

2.1.2.3 Sludge and water re-use ................................................................................ 24 

2.1.2.4 Health and wastewaters ................................................................................. 25 

2.1.3 Modernisation and Governance - problem and drivers ............................. 25 

2.1.3.1 Operators’ performances and transparency ................................................... 26 

2.1.3.2 Uneven application of the ‘polluter pays’ principle ...................................... 26 

2.1.3.2 Not adapted monitoring and reporting .......................................................... 27 

2.1.3.2 Insufficient access to sanitation .................................................................... 28 

2.2 How likely is the problem to persist? .................................................................. 28 

3.  WHY SHOULD THE EU ACT? .............................................................................. 29 

3.1 Legal basis ........................................................................................................... 29 
3.2 Subsidiarity: Necessity of EU action ................................................................... 29 
3.3 Subsidiarity: added value of EU action ............................................................... 30 

4.  OBJECTIVES: WHAT IS TO BE ACHIEVED? ..................................................... 31 

4.1 General objectives ............................................................................................... 31 
4.2 Specific objectives ............................................................................................... 31 

5.  WHAT ARE THE AVAILABLE POLICY OPTIONS? .......................................... 34 

5.1 What is the baseline from which options are assessed? ...................................... 34 

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5.2 Description of the policy options ........................................................................ 36 
5.2.1 Storm water overflows (SWO) and urban runoff ............................................. 37 

5.2.2 Small Agglomerations ...................................................................................... 38 

5.2.3 Loads from individual or other appropriate systems (IAS) ............................. 39 

5.2.4 N and P releases and eutrophication ................................................................ 39 

5.2.5 Micro-pollutants ............................................................................................... 40 

5.2.6 Non-domestic emissions .................................................................................. 41 

5.2.7 Energy .............................................................................................................. 41 

5.2.8 Sludge management and water re-use .............................................................. 44 

5.2.9 Wastewater and health ..................................................................................... 44 

5.2.10 Transparency and Governance ....................................................................... 45 

5.2.11 Monitoring and reporting ............................................................................... 45 

5.2.12 Access to sanitation ........................................................................................ 46 

5.3 Options discarded at an early stage ..................................................................... 46 

6.  WHAT ARE THE IMPACTS OF THE POLICY OPTIONS, HOW DO THEY COMPARE 

AND WHAT ARE THE PREFERRED OPTIONS? .......................................................................... 49 

6.1 Storm water overflows and urban runoff............................................................. 50 
6.2 Individual or other appropriate systems (IAS) .................................................... 53 
6.3 Small Agglomerations ......................................................................................... 53 
6.4 N and P releases and eutrophication .................................................................... 54 
6.5 Micro-pollutants .................................................................................................. 55 
6.6 Non-domestic Emissions ..................................................................................... 57 
6.7 Energy neutrality and GHG emissions ................................................................ 58 
6.8 Governance – transparency ................................................................................. 60 
6.9 Wastewater and health ......................................................................................... 60 
6.10 Access to sanitation ........................................................................................... 61 
6.11 Reporting ........................................................................................................... 61 

7. 

PREFERRED OPTION ...................................................................................................................... 64 

7.1 Preferred Option – summary ............................................................................... 64 
7.2 REFIT and “One in, One out” ............................................................................. 73 

8.  HOW WILL ACTUAL IMPACTS BE MONITORED AND EVALUATED? .................................. 75 

ANNEX 1: PROCEDURAL INFORMATION ............................................................................................ 77 

1. 

LEAD DG, DECIDE PLANNING/CWP REFERENCES .................................................................. 77 

2.  ORGANISATION AND TIMING ...................................................................................................... 77 

3. 

4. 

CONSULTATION OF THE RSB....................................................................................................... 77 

EVIDENCE, SOURCES AND QUALITY ......................................................................................... 81 

ANNEX 2: STAKEHOLDER CONSULTATION (SYNOPSIS REPORT) ................................................ 83 

1. CONSULTATION STRATEGY & ACTIVITIES ................................................................................... 83 

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2. STAKEHOLDER GROUP ....................................................................................................................... 85 

3. METHODOLOGY AND TOOLS USED TO PROCESS THE DATA ................................................... 86 

4. OPC – GENERAL VIEW......................................................................................................................... 87 

5.  STAKEHOLDERS’ VIEWS ON THE DIFFERENT AREAS ............................................................... 88 

6.  POSITION PAPERS ............................................................................................................................... 96 

ANNEX 3: WHO IS AFFECTED AND HOW? .......................................................................................... 98 

1. 

2. 

3. 

PRACTICAL IMPLICATIONS OF THE INITIATIVE..................................................................... 98 

SUMMARY OF COSTS AND BENEFITS ..................................................................................... 102 

RELEVANT SUSTAINABLE DEVELOPMENT GOALS ............................................................. 105 

ANNEX 4: ANALYTICAL METHODS ................................................................................................... 106 

ANNEX 5: SUMMARY OF MEMBER STATE SITUATION ................................................................. 129 

ANNEX 6:  ASSESSING COMPLIANCE ................................................................................................ 133 

ANNEX 7:  ADDITIONAL DETAILED INFORMATION ...................................................................... 135 

ANNEX  8:  MAIN  RELATIONS  BETWEEN  ONGOING  INITIATIVES  AND  THE  PRESENT 

INITIATIVE ..................................................................................................................................... 144 

ANNEX 9: ACTORS INVOLVED IN AN EPR SCHEME AND THEIR RESPECTIVE ROLES .......... 146 

ANNEX 10: LITERATURE REFERENCES ............................................................................................. 148 

3 

 
Glossary 

Term 

Explanation 

Agglomeration 

According  to  the  Urban  Wastewater  Treatment  Directive  (UWWTD): 
‘Agglomeration’  means  an  area  where  the  population  and/or  economic 
activities  are  ‘sufficiently  concentrated’  for  urban  wastewater  to  be 
collected and  conducted  to  an urban  wastewater treatment  plant or to a 
final discharge point. (Article 2(4)). 

An  agglomeration  can  be  a  city  or  municipality,  but  it  can  also  be  a 
number of smaller cities or towns clustered together.   

Anti-microbial 
Resistance 
(AMR)  

AMR  occurs  when  e.g.  fungi  and  bacteria  transform  over  time  and  no 
longer  respond  to  medications  (WHO,  2022).  The  main  drivers  of  the 
development of drug-resistant pathogens are misuse and overuse of anti-
microbials  e.g.  antibiotics,  antivirals,  antifungals  and  antiparasitics. 
AMR has been declared as one of the top 10 global public health threats 
facing humanity by the World Health Organization (WHO). 

Biochemical 
oxygen 
demand 
(BOD) 

According  to  the  UWWTD:  in  the  wastewater  discharge,  biochemical 
oxygen  demand  (BOD)  needs  to  be  reduced  to  25mg/l  of  Oxygen  or  a 
minimum reduction of 70-90% needs to be achieved. (Annex I). 

BOD is ‘the amount of dissolved oxygen used by micro-organisms in the 
biological  process  of  metabolising  organic  matter  in  water.  The  more 
organic matter there is (e.g. in sewage and polluted bodies of water), the 
greater  the  BOD.  And  the  greater  the  BOD,  the  lower  the  amount  of 
dissolved oxygen available for higher animals such as fishes. The BOD 
is therefore a reliable gauge of the organic pollution of a body of water. 
One of the main reasons for treating wastewater prior to its discharge is 
to lower its BOD — i.e., reduce its need of oxygen and thereby lessen its 
demand  from  the  streams,  lakes,  rivers,  or  estuaries  into  which  it  is 
released.’ (Britannica, 2019a). 

BOD  is  most  commonly  expressed  as  milligrams  of  oxygen  consumed 
per  litre  of  samples  over  5  days  of  incubation  at  20°C  –  this  is  called 
BOD5 (Sawyer et al., 2003).  In this text “BOD” means “BOD5”. 

The  UWWTD  states  that  chemical  oxygen  demand  (COD)  in  the 
wastewater discharge needs to be reduced to 125mg/l O2. Alternatively, 
a minimum reduction of 75% needs to be achieved.  

Chemical 
oxygen 

COD  ‘is  a  second  method  of  estimating  how  much  oxygen  would  be 
depleted  from  a  body  of  receiving  water  as  a  result  of  bacterial  action. 
While the BOD test is performed by using a population of bacteria and 

4 

 
 
 
 
demand 

other  micro-organisms  to  attempt  to  duplicate  what  would  happen  in  a 
natural  stream  over  a  period  of  five  days,  the  COD  test  uses  a  strong 
chemical  oxidising  agent 
(potassium  dichromate  or  potassium 
permanganate) to chemically oxidise the organic material in the sample 
of  wastewater  under  conditions  of  heat  and  strong  acid.’  (Woodard  & 
Curran, 2006).  

Collecting 
system 

The  UWWTD  defines  this  as  a  system  of  conduits  which  collects  and 
conducts urban wastewater. (Article 2(5)). 

Combined 
sewers 

Combined  sewers  are  defined  as  ‘Systems  that  carry  a  mixture  of  both 
domestic sewage and storm sewage’. Combined sewers typically consist 
of large-diameter pipes or tunnels, because of the large volumes of storm 
water  that  must  be  carried  during  wet-weather  periods.  They  are  very 
common  in  older  cities  but  are  no  longer  designed  and  built  as  part  of 
new sewerage facilities.’ (Britannica, 2019b).  

The UWWTD does not include a reference to contaminants of emerging 
concern. According to the Organisation for Economic Co-operation and 
Development  (OECD)  “Contaminants  of  emerging  concern”  (CECs) 
comprise a vast array of contaminants that have only recently appeared 
in water, or that are of recent concern because they have been detected at 
concentrations significantly higher than expected, or their risk to human 
and environmental health may not be fully understood. Examples include 
pharmaceuticals,  industrial  and  household  chemicals,  personal  care 
their 
pesticides,  manufactured 
products, 
transformation products’ (OECD, 2018). 

nanomaterials, 

and 

Contaminants 
of emerging 
concern  

The  Environmental  Quality  Standards  Directive  explains  pollutants  of 
emerging concern. Recital 26 states that ‘emerging pollutants … can be 
defined  as  pollutants  currently  not  included  in  routine  monitoring 
programmes  at  Union  level  but  which  could  pose  a  significant  risk 
requiring  regulation,  depending  upon  their  potential  eco-toxicological 
and toxicological effects and on their levels in the aquatic environment.’ 

Dilution rate  

In the context of this IA, the dilution rate refers to the ratio between the 
flow of released wastewater from  a treatment  plant  and the flow of the 
receiving body (river). A dilution rate of 10 means that 1 litre of released 
wastewater from the treatment plant is diluted in less than 10 litres in the 
river. Lower dilution rates represent more risks for the environment but 
also for potentially for public health.   

Distance to 
target  

‘Distance  to  target’  reflects  the  remaining  efforts  to  be  made  to  collect 
and treat the load generated in accordance with the requirements of the 
Directive. For instance, in 2018, 98% of the generated load is collected, 
across all Member States, in line with Article 3 of the Directive, meaning 
that, for this goal, the EU average distance to target is 2 %.       

5 

 
Eutrophication 

UWWTD  definition:  The  enrichment  of  water  by  nutrients,  especially 
compounds  of  nitrogen  and/or  phosphorus,  causing  an  accelerated 
growth of algae and higher forms of plant life to produce an undesirable 
disturbance to  the balance of organisms present  in  the water and to  the 
quality of the water concerned. (Article 2(11)). 

E. coli  

Fourth 
treatment  

Indicators of faecal contamination are commonly analysed in treated 
wastewater prior to discharge or reuse. Escherichia coli (E. coli) is one 
of the most commonly adopted indicators for the determination of the 
microbiological quality in water and treated wastewater since it is 
considered a good indicator of this type of contamination. It is also 
easily detectable, almost exclusively of faecal origin and its presence is 
linked to the presence of pathogens. Due to this, E. coli is used in most 
regulations regarding the microbiological quality of treated municipal 
wastewater (Vergine et al, 2017; Annex 10, report 1).  

Fourth treatment consist of micro-pollutant removal notably via 
ozonation and/or filtering with activated carbon or advanced techniques 
like nano-filtration, membranes.  It comes after tertiary treatment 
(Nitrogen treatment in particular) – which is a pre-requisite to ensure an 
optimal functioning of the 4th treatment. So far there is no obligation in 
the UWWTD to treat micro-pollutants. 

Individual or 
other 
appropriate 
systems 

(IAS) 

The UWWTD states that ‘where the establishment of a collecting system 
is not justified either because it would produce no environmental benefit 
or  because  it  would  involve  excessive  cost,  individual  systems  or  other 
appropriate  systems  which  achieve  the  same  level  of  environmental 
protection  shall  be  used.’  (Article  3(1)).  This  covers  simple  facilities 
such as sceptic thanks up to more sophisticated small facilities.  

Micro-
pollutants   

Emerging  micro-pollutants  are  defined  as  synthetic  or  natural 
compounds released from point and nonpoint resources and end up to the 
aquatic  environments  at  low  concentration  -  typically  µg/L  or  less 
(Barbosa et al., 2016) 

Pollutant  which  exists  in  very  small  traces  in  water  (Source:  EEA).  
Most  micro-pollutants  are  considered  as  “Contaminants  of  emerging 
concern” (see above).  In this IA and in the context of the study on EPR, 
a more specific definition focusing on organic substances was used (See 
report 2, Annex 10).  

Micro-plastics 

According  to  the  European  Chemicals  Agency  (ECHA),  ‘the  term 
“micro-plastic” is not consistently defined, but is typically considered to 
refer  to  small,  usually  microscopic,  solid  particles  made  of  a  synthetic 
polymer.  They  are  associated  with  long-term  persistence  in  the 
environment, if released, as they are very resistant to (bio)degradation.’ 

6 

 
 
 
UWWTD definition: ‘1 p.e. (population equivalent)’ means the organic 
biodegradable  load  having  a  five-day  biochemical  oxygen  demand 
(BOD5)  of  60  g  of  oxygen  per  day.’  In  this  IA,  one  p.e.  includes  on 
average 11.18 g/day for total Nitrogen, and 1.68 g/day for Phosphorus. It 
also includes a range of micro-pollutants (around 1.300 chemicals were 
considered in this IA) each having a specific load – see Annex 4.  

Population 
equivalent 
(p.e.) 

In  summary,  1  p.e.  describes  the  average  pollution  load  release  by  one 
person in one day. 

PRO – 
Producer 
Responsibility 
Organisation  

‘PRO’  are  organisations  set  up  by  the  sectors  subject  to  a  producer 
responsibility. Their role is to implement the legal obligation in the name 
of their Members. PRO’s are usually requested by law to establish self-
control  mechanisms  controlled  by  regular  independent  audits  for  both 
their  financial  management  and  the  quality  of  collected  and  reported 
data.  In  the  case  of  micro-pollutants,  PRO  would  collect  the  required 
funds based on their members’ declaration (quantities placed on the EU 
market and toxicity). They would then finance wastewater operators for 
more stringent treatment. 

Primary 
treatment 

Secondary 
treatment 

Tertiary 
treatment  

Toxic load  

PFAS  

According  to  the  UWWTD,  ‘Primary  treatment’  means  treatment  of 
urban  wastewater  by  a  physical  and/or  chemical  process  involving 
settlement of suspended solids, or other processes in which the BOD of 
the incoming wastewater is reduced by at least 20% before discharge and 
the total suspended solids of the incoming wastewater are reduced by at 
least 50% (Article 2(7)). 

UWWTD  definition:  ‘Secondary  treatment’  means  treatment  of  urban 
wastewater by a process generally involving biological treatment with a 
secondary  settlement  or  other  processes  in  which  the  requirements 
established in Table 1 of Annex I are respected (Article 2(8)). 

More  stringent  treatment  or  tertiary  treatment  is  the  third  stage  of 
treatment  and  can  consist  of  nutrient  removal,  chemical  or  physical 
disinfection.  In  the  UWWTD,  table  2  in  Annex  I  lays  down  the 
thresholds for nutrient reduction. 

In the context of this  IA an indicator of the toxic load was built on the 
basis  of  a  set  of  micro-pollutants  found  on  the  wastewaters  (pollutant 
quantity  weighted  by  toxicity  of  individual  substances  more  details  are 
provided in Annex 4. 

Per-  and  polyfluoroalkyl  substances  (PFAS)  are  a  large  family  of 
thousands of synthetic chemicals that are widely used throughout society 
and  found  in  the  environment. They  all  contain  carbon-fluorine  bonds, 
which are one of the strongest chemical bonds in organic chemistry. This 
means  that  they  resist  degradation  when  used  and  also  in  the 

7 

 
environment. Most PFAS are also easily transported in the environment 
covering long distances away from the source of their release.  

PFAS  have  been  frequently  observed  to  contaminate  groundwater, 
surface water and soil. Cleaning up polluted sites is technically difficult 
and costly. If releases continue, they will continue to accumulate in the 
environment, drinking water and food (Source: ECHA).  

PNEC  

The  ‘Predicted  No  Effect  Concentration’  is  the  concentration  of  a 
substance,  below  which  exposure  is  not  expected  to  cause  adverse 
effects.  E.g.,  a  concentration  of  a  pharmaceutical  for  which  no 
pharmacological effect is expected to occur for a specific organism.  

The UWWTD allows for the use of combined and separate sewers. 

Separate 
sewers 

Storm Water 
Overflows 

(SWO) 

Separate systems: “New wastewater collection facilities are designed as 
separate systems,  carrying either domestic sewage or storm  sewage but 
not both. Storm sewers usually carry surface runoff to a point of disposal 
in  a  stream  or  river.  Small  detention  basins  may  be  built  as  part  of the 
system, storing storm  water temporarily  and reducing the magnitude of 
the  peak  flow  rate.  Sanitary  sewers,  on  the  other  hand,  carry  domestic 
wastewater 
industrial 
wastewater  may  be  allowed  into  municipal  sanitary  sewerage  systems, 
but storm water is excluded.” (Britannica, 2019c). 

treatment  plant.  Pre-treated 

to  a  sewage 

A footnote in Annex I to the UWWTD states ‘…during situations such 
as unusually heavy rainfall, Member States shall decide on measures to 
limit  pollution  from  storm  water  overflows.  Such  measures  could  be 
based  on  dilution  rates  or  capacity  in  relation  to  dry  weather  flow  or 
could specify a certain acceptable number of overflows per year.’ 

As  mentioned  under  combined  sewers,  these  systems  carry  wastewater 
and  storm  water.  According 
to  Britannica,  ‘because  wastewater 
treatment  plants  cannot  handle  large  volumes  of  storm  water,  sewage 
must bypass the treatment plants during wet weather and be discharged 
directly  into  the  receiving  water.  These  combined  sewer  overflows, 
containing  untreated  domestic  sewage,  cause  recurring  water  pollution 
problems  and  are  very  troublesome  sources  of  pollution.’  (Britannica, 
2019b).  

Surface water 

inland  waters,  except 
Water  Framework  Directive  definition: 
groundwater; transitional waters and coastal waters, except in respect of 
chemical status for which it shall also include territorial waters. (Article 
2(1)). 

(Total) 
nitrogen 

Total  nitrogen  is  defined  in  the  UWWTD  as  ‘the  sum  of  total  Kjedahl 
nitrogen (organic and ammoniacal nitrogen), nitrate-nitrogen and nitrite-
nitrogen’.  The  UWWTD  requires  a  reduction  of  total  nitrogen  in 

8 

 
wastewater  discharges 
(in 
agglomerations  with  10.000  –  100.000  p.e.)  and  10  mg/1  N  (in 
agglomerations with more than 100.000 p.e.) (Annex I of the Directive). 

to  concentrations  of  15  mg/1  N 

Nitrogen  is,  together  with  phosphorus,  one  of  the  main  nutrients  in 
wastewater.  Nitrogen  becomes  ammonia/ammonium,  creating  an 
additional  oxygen  demand.  This  can  lead  to  excessive  plant  and  algae 
growth,  which  can  then  prevent  other  organisms  from  living  and 
growing. 

The  UWWTD  requires  a  reduction  of  total  phosphorus  in  wastewater 
discharges to concentrations of 2 mg/1 P (in agglomerations with 10.000 
–  100.000  p.  e.)  and  1  mg/1  P  (in  agglomerations  with  more  than 
100.000 p.e.) (Annex I). 

Together  with  nitrogen,  phosphorus  is  one  of  the  main  nutrients  in 
wastewater. Phosphorus becomes ortho-phosphate, creating an additional 
oxygen  demand.  This  can  lead  to  excessive  plant  and  algae  growth, 
which can then prevent other organisms from living and growing. 

(Total) 
phosphorus 

Urban runoff  

 Urban  runoff  consist  of  storm  water  from  city  streets  and  private  or 
commercial  properties  that  contains  litter,  as  well  as  organic  and 
bacterial  waste  (EEA  glossary).  Depending  on  local  conditions,  urban 
runoff can be collected in combined or separate networks.  

Urban 
wastewater 

The UWWTD defines ‘urban wastewater’ as domestic wastewater on its 
own  or  domestic  wastewater  mixed  with  industrial  wastewater  and/or 
runoff rain water. (Article 2(1)). 

Water 
resilience  

‘Resilience’ is the quality of being able to return quickly to 
a previous good condition after problems. (Source: Cambridge 
Dictionary). ‘Water resilience’ refers to those characteristics in a water 
system (droughts, floods, water pollution).    

9 

 
 
 
 
 
Abbreviations 

Term or abbreviations 

Meaning or definition 

AMR 

BWD 

BOD 

COD 

CJEU 

CSO 

DWD 

ECA 

ECHA 

EEA 

Antimicrobial resistance 

Bathing Water Directive 

Biochemical oxygen demand 

Chemical oxygen demand 

Court of Justice of the European Union 

Combined sewer overflow 

Drinking Water Directive 

European Court of Auditors 

European Chemicals Agency 

European Environment Agency 

E-PRTR 

European Pollutants Release and Transfer Register  

EED  

EPR 

EQS 

EU 

GHG 

GWh 

Energy Efficiency Directive  

Extended Producer Responsibility  

Environmental quality standards 

European Union 

Greenhouse gas  

Gigawatt hour 

10 

 
Term or abbreviations 

Meaning or definition 

IAS 

IED 

IPCC 

JRC  

Individual or other appropriate system 

Industrial Emissions Directive 

Intergovernmental Panel on Climate Change 

European Commission Joint Research Centre 

MSFD 

Marine Strategy Framework Directive 

N 

ND 

NVZ 

OECD 

OPC 

P 

PFAS 

p.e. 

PNEC 

PRO 

RBMP 

REACH 

Nitrogen 

Nitrates Directive 

Nitrates vulnerable zones 

Organisation for Economic Cooperation and 
Development 

Open Public Consultation 

Phosphorus 

Perfluoroalkyl chemicals 

Population equivalent 

Predicted No Effect Concentration 

Producer Responsibility Organisation  

River basin management plan 

Registration, evaluation, authorisation and restriction of 
chemicals 

11 

 
Term or abbreviations 

Meaning or definition 

REDII 

RTC 

SME’s 

SSD 

SWO 

Proposal of revision of the Renewable Energy Directive  

Real time control  

Small and medium-sized enterprises 

Sewage Sludge Directive 

Storm water overflow 

UWWTD 

Urban Wastewater Treatment Directive 

WFD 

Water Framework Directive 

12 

 
 
 
1. 

INTRODUCTION: POLITICAL AND LEGAL CONTEXT 

The  European  Union  adopted  in  1991  the  Urban  Wastewater  Treatment  Directive 
(UWWTD). The objective of this Directive is to “protect the environment from adverse 
effects  of  wastewater  discharges  from  urban  sources  and  specific  industries”.  Member 
States (MS) are required to ensure that wastewater from all agglomerations above 2.000 
inhabitants  is  collected  and  treated  according  to  minimum  EU  standards.  Stricter 
standards  apply  for  ‘sensitive  areas’  which  have  to  be  identified  by  MS  according  to 
criteria included in the Directive – for instance in case of risk of eutrophication.   

to 

MS report every two  years on the implementation of the Directive. This  information  is 
published by the Commission in biennial reports. Across the EU, 21.708 agglomerations 
generating  wastewater  equivalent 
the  pollution  from  517 million  population 
equivalents  (p.e.)1  are  treated  in  centralised  systems.  Wastewater  operators  are  either 
private companies operating for a public competent authority or public companies owned 
by  the  public  competent  authorities  (around  60%)  or  mixed  companies.  Collection  and 
treatment of urban wastewater have improved over the last decade: 98% of the generated 
load is appropriately collected, 92% meet the primary and secondary treatment standards 
(basic  treatment  of  organic  pollution  –  see  glossary),  while  another  92%  meet  more 
stringent  treatment  standards  (tertiary  treatment  removing  Nitrogen  and  Phosphorus). 
There are differences between MS  – a limited number of MS still having difficulties to 
reach compliance (Annex 7, Table 1).  

The  2019  UWWTD  REFIT  Evaluation  (hereby  referred  to  as  ‘the  Evaluation’),  which 
entailed  a  comprehensive  stakeholder  consultation,  confirmed  that  the  Directive’s 
implementation  has  caused  a  significant  reduction  of  pollutant  releases.  The  effects  on 
the quality of the EU lakes, rivers and seas are visible and tangible. The Evaluation also 
identified remaining challenges which served as a basis for the definition of the problem 
for this impact assessment (IA). MS supported the main findings of the Evaluation during 
an  Environment  Council  meeting  as  well  as  the  European  Parliament  through  a 
Resolution focusing on the need to improve the energy balance of the sector. There is a 
large  consensus  in  the  Council  and  the  Parliament,  as  well  as  within  the  stakeholder 
community,  on  the  need  to  modernise  the  Directive  and  to  better  link  it  with  the 
European  Green  Deal  (EGD)  ambitions.  Similarly,  the  European  Committee  of  the 
Regions agreed with the Evaluation findings, pushing for a revision of the UWWTD to 
adapt  it  to  new  societal  needs  and  urging  the  Commission  to  better  apply  the  “polluter 
pays” principle.    

Since  the  publication  of  the  Evaluation,  the  EU  took  important  steps  to  set  out  its 
ambitions with the adoption of the European Green Deal. The review of the Directive is 
included  as  one  of  the  actions  of  the  Zero  Pollution  Action  Plan  (ZPA),  in  close 
connection with a sound implementation of the Chemicals Strategy for Sustainability and 
the Pharmaceuticals Strategy. There are direct connections with the Biodiversity Strategy 
as reducing water pollution has a direct beneficial effect to ecosystems. Actions to green 
the cities, such as those stemming from the upcoming  Nature Restoration Law, can not 

1 In this impact assessment, the standard unit to measure pollution is the ‘population equivalent’ (p.e.) – see 
Glossary.  For  some  pollutants  (N,  P  and  BOD)  it  is  possible  to  convert  p.e.  into  tons.  The  wastewater 
treatment plants treat water mainly from inhabitants, but also from small enterprises or rain waters, which 
explains why total number of covered p.e. is higher than the total number of EU27 citizens.      

13 

 
                                                           
 
only create a good habitat for pollinators, birds and other species, but also directly help to 
control rain water and related pollution, while improving the overall quality of life. Better 
management  of  water  quality  and  quantities  in  the  urban  areas  will  also  contribute  to 
climate  adaptation.  The  new  Circular  Economy  Action  Plan  sets  out  that  a  better 
integration of the urban  wastewater sector with the circular economy is needed. This is 
particularly relevant for the Sewage Sludge Directive (currently being evaluated), which 
regulates the use of sewage sludge in agriculture and has implications for the  Soil Health 
proposal announced in the EU Soil Strategy for 2030.  

Furthermore,  the  EU  climate  neutrality  objective  as  included  in  the  EU  Climate 
Regulation,  combined  with  the  Effort  Sharing  Regulation,  requires  MS  to  reduce  their 
GHG emissions according to national objectives from the sectors such as the wastewater 
treatment  sector  which  are  not  covered  by  the  EU  Emission  Trading  Scheme.2    At  the 
same time, the recent recast proposal of the Energy Efficiency Directive (EED) requires 
MS to reduce their overall energy consumption by 9% by 2030 compared to 2020, while 
including a specific target of 1,7% reduction each year of the energy consumption of all 
public  bodies.  The  EED  also  includes  the  obligation  to  achieve  energy  audits  for 
enterprises  consuming  large  amounts  of  energy.  As  detailed  in  section  2.1.2.2,  a  large 
part of the UWWT facilities would be excluded from this obligation. The 2021 proposal 
for  a  revision  of  the  Renewable  Energy  Directive  (“REDII”)  includes  an  objective  of 
40%  of  renewable  energy  in  the  energy  mix  by  2030.  The  Evaluation  showed  that  the 
wastewater sector has specific potential not only to reduce its own energy consumption, 
currently amounting to around 0.8% of the overall EU energy use, but also to produce, in 
a steady and reliable manner not dependent on weather variations, renewable biogas out 
of sewage sludge next to offering well-suited locations for the production of renewable 
energies (wind and solar). This sector-specific potential should be untapped, in line with 
the  recently  adopted  Repower  EU  Communication  insisting  on  the  need  to  accelerate 
action for more affordable, secure and sustainable energy, including from biogas.   

Over the past months it has become apparent that surveillance of different health related 
parameters  in  wastewaters  can  provide  useful  information  for  public  health  purposes. 
This was the case with  SARS-CoV-2 virus and its variants monitoring in wastewaters, 
used as a complementary approach to public health measures. To support the use of this 
tool and enhance the early detection capacities across all MS the Commission published a 
Recommendation and provided in 2021 financial support to 26 MS. Also in line with the 
“A Europe fit for the Digital Age” Communication, the potential benefits of digitalisation 
should be further explored as they are particularly relevant in the water sector. 

The  revision  of  the  UWWTD  is  linked  to  the  revision  of  the  pollutants  lists  under  the 
Environmental  Quality  Standards  Directive  and  the  Groundwater  Directive  –  two 
‘daughter’  Directives  of  the  Water  Framework  Directive  (WFD),  regulating  the 
acceptable levels of pollutants in surface and ground water bodies. It is also connected to 
the revision of the Industrial Emissions Directive (IED) and the related review of the E-
PRTR  Regulation,  as  some  industrial  emissions  are  collected  in  public  collection 
networks.  It  will  have  a  positive  impact  on  the  ongoing  review  of  the  Marine  Strategy 
Framework Directive (MSFD) and on the review of the Bathing Water Directive (BDW). 
These  parallel  revisions  and  reviews  help  to  ensure  that  any  coherence  issues  can  be 
resolved.  N  emissions  to  the  environment  are  regulated  both  by  the  UWWTD  (urban 

2 The main interactions of this initiative with other ongoing initiatives are summarised in Annex 8.   

14 

 
                                                           
pollution) and by the Nitrates Directive (N from agriculture) and, as recalled in the ZPA, 
the  revision  of  the  UWWTD  will  support  the  concrete  implementation  of  the  future 
Nutrient Management Action Plan. Over the last decades, the UWWTD has contributed 
to achieving the Sustainable Development Goals (SDGs), in particular SDG 6 on access 
to adequate and equitable sanitation and hygiene for all. Most MS have signed the 1999 
UN  Protocol  on  Water  and  Health,  setting  out  requirement  on  access  to  sanitation.  As 
such,  it  contributes  to  achieving  the  commitments  made  under  the  European  Pillar  of 
Social Rights Action Plan on access to essential services.   

2.  PROBLEM DEFINITION 

2.1 What are the problems and their drivers? 

In the Evaluation, three main sets of problems were identified, which are discussed in 
more depth below together with their drivers:  

1)  Remaining pollution from urban sources (section 2.1.1);  
2)  Insufficient  alignment  of  the  Directive  to  new  societal  ambitions  and  the  Green 

Deal objectives (section 2.1.2);  

3)  Insufficient/uneven level of governance of the sector (section 2.1.3).   

The  stakeholder  consultation3  showed  a  broad  consensus  on  (1)  the  necessity  to 
undertake  a  revision  of  the  Directive,  and  (2)  the  list  of  problems  to  be  tackled  in  a 
possible  review.  No  other  important  issue  emerged  during  the  different  consultations. 
Overall,  no  major  problems  of  coherence  with  other  legislation  were  found  in  the 
Evaluation,  even  if  some  adjustments  might  be  needed  as  several  Directives  were 
adopted after the UWWTD. This is further detailed in the ad hoc sections below.     

2.1.1 Remaining pollution from urban sources – problem and drivers  

The Evaluation provided a first quantification of the remaining sources of pollution not 
optimally  addressed  by  the  Directive.  This  quantification  was  updated  and  fine-tuned 
using the same model developed by the JRC for the Evaluation (see Annexes 1 and 4). 
The Evaluation also pointed to the new types of pollutants requiring more attention (such 
as micro-pollutants) having emerged since the adoption of the Directive.  

At  the  time  of  its  adoption  the  focus  of  the  Directive  was  on  organic  pollution  from 
domestic sources emitted in usual (‘dry weather’) conditions and collected and treated in 
centralised facilities, for which the requirements are clear and precise. Less attention was 
given  to  rain  waters,  smaller  agglomerations  and  individual  appropriate  systems  for 
which the requirements were kept more generic. The emissions from these sources have 
progressively  become  equivalent  to  the  releases  from  centralised  facilities.  This  is 
illustrated  in  modelling  results  presented  in  Table  1  and  Figure  1  below  showing  the 
remaining load of pollutants rejected in the environment from different sources. The total 
initial load generated amounts to 708,8 p.e. Of this, 517 million p.e. is sent to centralised 
wastewater treatment plants and 191,8 million p.e. is not collected and thus not treated in 
centralised facilities (49,3 million p.e. is generated in small agglomerations, 16,5 million 
in IAS and 126 million are coming from SWO/urban runoff.) 

3 More details on stakeholder views are provided in Annex 2 and in Appendix F of the report 1 (Annex 10). 
When divergent views amongst stakeholders were expressed, they are reported in the main text of this IA.    

15 

 
                                                           
Micro pollutants

E.Coli

Phosphorus

Nitrogen

BOD

 -

 50.000.000  100.000.000  150.000.000  200.000.000  250.000.000  300.000.000

Population equivalent per year 

SWO
Compliant IAS
Remaining compliant treated load

Urban run off
Small Agglo

Non Compliant IAS
Non compliant load

Figure  1:  Remaining  loads  from  urban  sources  (p.e./year)  -  Source  JRC  -  see  Annex  4. 
Breakdown per MS is provided in Table A7.5 in Annex 7 

The remaining load  sent to  the environment varies from  one pollutant to  another (from 
66,2 million p.e. for BOD to 264 million p.e. for micro-pollutants). Part of this pollution 
could be avoided. However, as shown in Table 1, with the maximum feasible scenario4, 
there  are  limits  to  what  can  be  technically  achieved:  with  the  current  techniques,  it  is 
indeed impossible to remove and treat 100% of the load from the wastewaters (between 
48% for BOD to 92% for E. Coli – could be removed - see line (5) in Table 1).     

BOD (p.e.) 

Nitrogen 
(p.e.) 

Phosphorus 
(p.e.) 

E. coli 
(p.e.)  

Micro 
pollutants 
(p.e.) 

54.993.361  

57.159.194  

26.752.894  

39.395.928  

51.224.149  

(1) Remaining load from 191,8 
million p.e. from  SWO/urban 
runoff, small agglo., and IAS   
(2) Remaining load from 517 
million p.e. sent to centralised 
facilities after treatment  
(3)Total remaining load (1) + (2) 
(4) Remaining load if maximum 
feasible treatment is applied  
(5) % of the remaining load 
which is ‘treatable’((3) –(4))/(3) 
Table 1: Remaining loads sent to the environment (p.e./year) - source JRC - see Annex 4. 
More details are provided in Annex 7, Table A7.2 and Table A7.5 (details per MS)  

133.967.530  

191.126.725 

148.600.784 

264.127.257 

130.837.224 

19.886.613  

93.607.423  

88.219.608 

71.110.762 

47.658.013 

66.148.823 

34.239.042 

5.736.591 

48,24% 

53,84% 

67,93% 

91,93% 

50,46% 

105.766.283  

158.360.974  

2.1.1.1 Non-compliant agglomerations  

Discharges  from  non-compliant  agglomerations  above  2.000  p.e.  represent  around 
6,7% of the remaining load for BOD, 1,9% for Nitrogen (N), 7,78 % for Phosphorus (P) 
and 7,4% for bacteria (E. coli). The Evaluation pointed out that the deadlines set in the 

4  This  scenario  was  built  as  a  reference  using  all  the  available  treatment  techniques  without  taking  into 
account costs – see Annex 4 for more details.   

16 

 
 
 
            
            
            
            
         
            
         
            
            
         
                                                           
Directive  might  have  been  overly  ambitious  for  some  MS.  As  explained  in  the 
Evaluation,  effective  legal  actions  were  taken  by  the  Commission  to  ensure  timely  and 
correct implementation of the Directive. More than 40 CJEU rulings were issued against 
nearly all MS and 30 horizontal cases are still open today. Despite significant  progress 
accomplished  by  MS,  implementing  the  Directive  remains  challenging  in  a  limited 
number of them (see Annex 7, Table 1).  

The Evaluation showed that this is mainly due to the lack of institutional/administrative 
capacity, combined to a lesser extent with insufficient financing capacities. At the same 
time,  some  MS  have  managed  to  fully  implement  the  Directive  in  a  rather  short  time, 
particularly  MS  having  joined  the  EU  after  2004.  Such  better  performances  are  mainly 
due to a proper organisation and planning of the required investments combined with a 
sound  financing  strategy  and  the  support  of  EU  funds.  These  MS  have  also  benefitted 
from  newest  and  more  effective  technologies  compared  to  MS  having  invested  in  their 
infrastructures after the adoption of the 1991 Directive.      

2.1.1.2 Storm water overflow (SWO) and urban runoff 

During rainfall events, storm water overflows (SWO- see Glossary) and urban runoff 
represent  a  sizeable  remaining  source  of  loads  sent  to  the  environment:  19%  of  the 
remaining  load  for  BOD,  7,2%  for  Nitrogen,  9,5%  for  Phosphorus,  29,77%  for  E.  coli 
and 25,7% for micro-pollutants (see Figure 1). These emissions are expected to increase 
due  to  the  combined  effects  of  urbanisation  and  progressive  change  of  the  rain  regime 
due to climate change. Most of this pollution takes place during a relatively short period 
of  time  bringing  suddenly,  in  the  receiving  water  body,  a  peak  of  untreated  pollutants 
including waste and litters from the streets, such as plastics and micro-plastics (‘flushing 
effect’).  The  Evaluation  showed  that  part  of  this  pollution  is  due  to  a  lack  of  detailed 
provisions in the Directive: in case of heavy rain, MS have indeed the possibility to send 
directly to the environment part of SWO and urban run-off without any need for previous 
treatment.5   

Reporting under the WFD showed that at least 15% of UWWTPs above 10.000 p.e. are 
in  waterbodies  failing  to  meet  the  WFD  ecological  status  due  to  SWO pressure.6 
According  to  a  report  from  the  EEA,  the  absence  of  proper  management  measures  for 
SWO and urban run-off combined with the increasing number of heavy rains events due 
to climate change are the main reasons why the limit values of the BWD for bacteria are 
exceeded  in  several  EU  bathing  areas.  The  situation  differs  from  one  agglomeration  to 
another  depending  on  the  local  conditions  (rainfall  patterns,  density  of  population, 
the 
urbanisation  green  spaces),  but  also  according 
collecting/treatment system.  

the  performance  of 

to 

The Evaluation also showed that the lack of specific provisions in the Directive has led to 
an  uneven  management  of  the  issue  across  the  MS  (see  Annex  5).  Only  very  few  MS 
have put in place systematic integrated water management approaches in their cities: the 
division  of  competences  between  services  in  charge  of  wastewater  collection  and/or 

5 Annex I to the  Directive  states ‘during situations such as unusually heavy rainfall, MS shall decide on 
measures  to  limit  pollution  from  SWO.  Such  measures  could  be  based  on  dilution  rates  or  capacity  in 
relation to dry weather flow or could specify a certain acceptable number of overflows per year.’ 
6 it was not possible to assess the status of another 15% of UWWTPs. 

17 

 
                                                           
treatment,  urban  planning,  monitoring  of  water  bodies  quality,  often  represents  an 
obstacle for designing integrated, optimal and cost effective solutions.  

2.1.1.3 Individual appropriate systems (IAS) 

As seen in Figure 1 and Table A7.2 in Annex 7, the use of IAS contributes to 15,7% of 
the  remaining  load  for  BOD,  7%  for  N,  8,6%  for  P,  16,1%  for  E.  coli  and  4,7%  for 
micro-pollutants.  The  Directive  allows  the  use  of  these  individual  systems  where 
building  a  collecting  system  comes  at  disproportionate  costs,  and  as  long  as  these 
systems achieve the ‘same level of environmental protection’ as in a centralised plant.  

However,  in  the  absence  of  more  precise  requirements,  it  is  difficult  to  verify  whether 
IAS are conform or not. Also, some MS report high and non-justified use of IAS (Figure 
2) in their agglomerations above 2.000 p.e. (more than 21% of the total load in Croatia).  

Figure 2: Percentage of reported generated load treated by IAS in agglomerations above 2.000 
p.e. in 2018, Source: Annex 10, report 7  

There is a variety of requirements for IAS set at national level, with a few MS applying 
best practices in terms of design, maintenance, monitoring and reporting (see Annex 5 for 
more details). Some MS (such as AT, DE, NL, BE and FR) have put in place their own 
national  environmental  standards  to  complete  or  replace  the  standards  laid  down  under 
the  Construction  Product  Regulation  (CPR)  for    smaller  facilities  below  50  p.e.  The 
multiplication  of  national  standards  has  resulted  in  some  degree  of  disruption  of  the 
internal market – but also in some confusion, as the ‘CE marking’ under the CPR does 
not  relate  to  the  environmental  performances  of  the  installations  (source:  Annex  10, 
report 16).7 Under the March 2022 proposal for reviewing the CPR, wastewater treatment 
would be excluded from the CPR scope. This will contribute to clarify the situation while 
increasing the importance of developing environmental standards under the UWWTD.  

7 The main reports used for this IA are referenced in the first part of Annex 10.  

18 

 
 
 
                                                           
2.1.1.4 Small agglomerations   

Small agglomerations are covered by the Directive only in a very general manner8 and 
yet constitute a significant pressure on 11% of the EU’s surface water bodies (EEA): as 
shown in Figure 1, around 24,9% of the remaining load for BOD, 15,8% for N, 18,9% for 
P, 26,2% for E. coli and 9,7% for micro-pollutants. The situation varies across MS: some 
MS  like  AT,  DE,  SE  and  FR  have  established  in  their  legislation  that  all  urban 
wastewater needs to be treated. Other MS have set standards for smaller agglomerations 
with a few, like EE, IE and PT, going beyond the requirements set out in the Directive. 

2.1.1.5 Remaining releases from Nitrogen and Phosphorus    

Despite  the  significant  reduction  of  emissions  achieved  with  the  existing  Directive  for 
Nitrogen  and  Phosphorus9,  wastewater  treatment  plants  remain  an  important  point 
source of both N and P (see Figure 3). Released wastewater is a more important source 
of  P  than  fertilizers  used  in  agriculture.  N  from  urban  wastewater  is  the  second  most 
significant source of inputs into rivers and seas after agriculture.  

Figure 3: Loads of N (tonnes/year) to EU regional seas by source (JRC).   

As  shown  during  the  stakeholder  consultation  (see  Annex  2),  the  problem  is  due  to  a 
combination  of  two  factors:  (1)  not  enough  areas  were  designated  by  the  MS  as 
‘sensitive’ for eutrophication, and (2) the standards of the Directive for N/P are outdated.  

Under Article 5.1 of the Directive, MS are required to designate ‘sensitive areas’ subject 
to eutrophication and apply either more stringent standards for N/P for each facility or an 
overall  load  reduction  rate  for  N/P.  The  Evaluation  showed  that  MS  have  applied  the 
Directive in different ways (see Figure 4) leading to some inconsistencies: for the same 
river the designation might not be the same. It means that the efforts made by some MS 
to  reduce  N/P  are  undermined  by  the  lack  of  efforts  by  others.  On  the  contrary,  in  the 
Baltic  Sea  basin,  for  instance,  coordination  is  ensured  at  regional  level:  the  same  more 
stringent standards for N/P is applied for all incoming waters.  

8 MS have to ensure ‘appropriate treatment’ from agglomerations of less than 2.000 p.e. (Article 7). 
9 Emissions from treatment plants are reduced from 517 to 134 and 94 million p.e. for N and P. 

19 

 
 
 
                                                           
From  MS  current  practices10,  it  appears  that  emission  limit  values  in  the  Directive  for 
N/P  could  be  reinforced:  several  MS  (DE,  AT,  NL,  HU  and  DK)  are  achieving  better 
performances than those prescribed by the minimum requirements of the Directive.  

N  and  P  releases  are  directly  contributing  to  eutrophication  (see  Glossary)  which 
remains an important problem in several rivers, lakes and seas in the EU. According to 
the EEA assessment, there are significant impacts from nutrient pollution on 426.267 km 
of  rivers  and  19.460  km2  of  lakes  across  the  EU.  According  to  a  recent  report  on  the 
implementation  of  the  MSFD,  eutrophication  occurs  in  the  Baltic  and  the  Black  Seas, 
along the North-western coast of France within the North-east Atlantic Ocean and along 
coastal areas mainly in the vicinity of riverine outflows within the Mediterranean Sea.  

Figure 4: Overview of sensitive areas and their catchments in the EU (2016) - Article 5(2-3): 
more stringent treatment > 10.000 p.e.; Article 5(4): 75% removal of  N and P; Article 
5(8): more stringent treatment on the whole country, Source: Annex 10, report 7. 

2.1.1.6 Micro-pollutants and Micro-plastics   

As shown in the Evaluation, the scientific community, policy makers and general public 
consider the growing evidence of  micro-pollutants and  micro-plastics in water bodies 

10  More  details  on  the  starting  position  of  each  MS  are provided  in  Annex  5  but  also  in Annex  4, Table 
A4.5 and Annex 7, Table  A7.5 

20 

 
 
 
                                                           
 
an  increasingly  important  issue.  The  need  for  action  was  also  highlighted  in  the 
Commission’s recent strategies.11  

Micro-pollutants  arise  from  the  use  of  many  products  in  households.  Pharmaceuticals 
and  to  a  lesser  extent  Personal  care  products  (PCP)  represent  a  large  share  of  the 
potentially harmful substances found in  wastewater (see report 2, Annex 10). The toxic 
load (see glossary) corresponding to 264 million p.e. is emitted to the environment, part 
of it (158 million p.e.) coming from  centralised treatment plants, the rest  being emitted 
by other sources (see Table 1 and Figure 1). Part of these emissions are taking place in 
rivers with a relatively low dilution rate, leading to higher risk of toxicity: the outlet of 
around 115 million  p.e.  are  emitted in  rivers with a dilution rate lower than  5  (Source: 
JRC,  Annex  10,  reports  13  and  14).  Their  accumulation  in  the  environment  and  the 
creation of ‘hot spots’ with low dilution rates are becoming a serious environmental and, 
in some instances, public health concern, notably where the downstream waters are used 
for bathing or for extracting and producing drinking waters.12  

As shown in the Evaluation and in Figure 5, micro-pollutants are now detected in all EU 
waters.  The  cumulative  effects  of  these  substances,  notably  in  fish  communities,  were 
already shown on several occasions: fish exposed to micro-pollutant residues may change 
their  behaviour,  harming  their  survival  abilities,  or  even  change  sex,  harming  their 
reproduction abilities and fertility rates.   

Figure 5: Number of pharmaceuticals detected in surface, ground or drinking water.  Source: 
Aus der Beek et al., 2015 

These  findings  were  confirmed  by  a  2022  study  on  pharmaceutical  pollution  (US 
National Academy of Science) based on samples from 1.052 locations in 104 countries 
from  all  continents.  25.7%  of  the  samples  included  at  least  one  pharmaceutical  in 
concentration  higher  than  what  is  considered  safe  for  aquatic  organisms.  According  to 
this study, ‘pharmaceutical  pollution poses a global  threat  to  environmental and human 
health, as well as to the delivery of the United Nations Sustainable Development Goals’. 

Plastics  and  Micro-plastics:  Most  of  the  micro-plastics  found  in  the  domestic 
wastewaters  directly  stem  from  the  use  of  textiles  (micro  fibres  emitted  during  the 
washing of clothes). They also come from the degradation of tyres on the roads or from 
the uncontrolled use of plastic pellets in plastic production, when wastewaters are mixed 

11  Including  the  Plastics  Strategy,  the  Strategic  Approach  to  Pharmaceuticals  in  the  Environment,  the 
Chemical Strategy,  the Zero Pollution Action Plan.  
12 Additional treatment is applied for the production of drinking  water. In line  with the revised  Drinking 
water Directive, all efforts should be done to reduce sources of pollution at source  

21 

 
 
                                                           
with rain waters (source Annex 10, report 3). The recently adopted  Textile strategy as 
well  as  the  upcoming  EU  initiative  on  Micro-plastics  are  expected  to  reduce  micro-
plastics emissions from these sources. As a result, less micro-plastics from these sectors 
should over time be found in incoming waters of the urban wastewaters treatment plants.  

Currently,  when  collected  and  sent  to  centralised  treatment  facilities,  nearly  all  large 
pieces  of  plastics  are  removed  at  the  beginning  of  the  treatment  process.  Also  micro-
plastics  are  relatively  well  captured  in  the  treatment  plants  –  80,5%  with  a  primary 
treatment, 97,5% with a secondary treatment and 99,2% with a tertiary treatment (Annex 
10, report 8). Significant amounts of (micro) plastics can be released in the environment 
in case of heavy rains (see previous section 2.1.1.2). It thus remains crucial to secure that 
appropriate measures are put in place in order to cater for SWO/urban run offs.  

The captured micro-plastics are partly degraded in the treatment plants. A recent Swedish 
study  show  that  about  40-60%  of  the  micro-plastics  in  the  incoming  wastewater  were 
found  in  the  sludge.  This  is  confirmed  by  another  recent  Norwegian  study:  over  500 
billion micro-plastic pieces are released each year into the environment via sludge use on 
the  soils.  As  half  of  the  sludge  is  used  agriculture  in  the  EU  (see  Figure  8  below), 
attention should be given to the presence of micro-plastics in the sludge and then in the 
soils.  

Micro-plastics  biomedia  (micro  pieces  of  plastics  used  in  very  specific  treatment 
process)  are  also  used  in  a  limited  number  of  wastewater  treatment  plants  (0,1%  in 
France in 2016). According to a report from the Surfrider foundation, significant amount 
of micro-plastics were found under the stream of such wastewater plants.13   

2.1.1.7 Non domestic releases    

Treatment  plants  covered  by  the  UWWTD,  although  designed  to  treat  ‘domestic 
wastewaters’, also receive other types of waters including industrial wastewaters, mainly 
from  SMEs.  These  wastewaters  can  include  a  range  of  pollutants  not  targeted  by  the 
Directive  such  as  heavy  metals,  micro-pollutants  or  other  chemicals.  Wastewater 
operators are in the first line when harmful releases are not controlled enough. 

Under Article 11 of the Directive, industrial releases in the public network are subject to 
pre-authorisation  and,  if  required  pre-treatment.  Releases  to  water  from  the  larger 
installations regulated by the  Industrial Emission Directive (IED) are already subject to 
authorisation  requirements.  As  detailed  in  the  Impact  Assessment  (adopted  by  the 
College on 5 April 2022) on the review of the IED, there is a need to better align the IED 
and the UWWTD to avoid the release of pollutants not abated in urban treatment plants 
into the public network. When it comes to releases from smaller installations not covered 
by the IED, the consultation showed that the regulatory approach, the level of control as 
well  as  the  degree  of  involvement  of  wastewater  operators  in  the  permitting  process 
differ from one MS to another (see Annex 5).  

Since  the  UWWTD  entails  no  requirement  for  monitoring  and  reporting  on  such  non-
domestic  pollution  entering  the  wastewater  treatment  plants,  it  is  difficult  to  provide  a 
quantification of this issue. The current lack of understanding prevents additional actions 

13 notably in FR, PT, ES but also in Switzerland.   

22 

 
                                                           
 
to  reduce  pollution  at  source  notably  through  stricter  permits  and  better  control  of 
industries connected to the public network.  

2.1.2 Alignment with Green Deal, new societal challenges - problems and drivers  

Since the adoption of the Directive, new societal challenges have emerged. The European 
Green  Deal  (EGD)  sets  ambitious  policy  objectives  to  fight  climate  change  and 
environmental degradation. The below listed topics are the most relevant aspects of the 
EGD to which the UWWTD needs to align.   

2.1.2.1 Green House Gas emissions  

In 2018, wastewater treatment was responsible for 34,45 million tons CO2e/year - around 
0,86% of the total GHG emissions of the EU including 4% of methane (CH4) and 3% of 
Nitrous Oxide (N2O) emissions (source: Annex 10, report 9). GHG emissions are specific 
to  each  facility  and  the  type  of  treatment  applied.    As  shown  in  Figure  6,  14,1  million 
tons CO2/year are due to carbon footprint of the infrastructures (mainly sewer networks). 
Another  3,98  million  tons  is  due  to  rejected  effluents  and  further  degradation  of  the 
remaining load. A last part – 3,34 million tons - is linked with the use of inputs produced 
by other industries, such as chemicals used for the treatment. These emissions cannot be 
avoided with measures in the wastewater sector.  

The  remaining  and  avoidable  GHG  emissions  (13,03  million  tons)  are  related  to 
operational  activities:  use  of  energy  (electricity)  for  the  collection  and  treatment  of 
wastewaters  (4,6  million  tons)  and  emissions  linked  with  the  treatment  process  (8,4 
million  tons  –  diffuse  emissions  of  N2O  in  the  process).  The  potential  impacts  of  the 
existing or forthcoming EU legislations on GHG emissions is discussed in section 5.1 on 
the baseline.  

GHG emissions - Waste Water (EU 27, tons 
CO2e/year)

Energy use

Process

Effluents

Infrastructures

 -

 5.000.000

 10.000.000

 15.000.000

Figure 6: Breakdown of GHG emission from wastewater sector – EU 27, source JRC 2022, ref 
in Annex 10, report 9 

2.1.2.2 Energy use  

As shown in Figure 7, there are large differences between operators in terms of energy 
use  depending  on  the  size  of  the  facilities  and  the  technologies  in  place.  Overall,  the 
wastewater sector is using about 0,8% of the total EU energy consumption. This comes at 
high  expenses:  around  €2  billion  per  year  representing  between  25%  and  56%  of  the 

23 

 
 
operational costs (source: Annex 10, report 1). Despite the significant potential, there is a 
poor  uptake  of  energy  efficiency  and  renewable  technologies  in  the  sector.  The 
Evaluation  showed  that,  apart  from  some  advanced  MS  (see  Box  1),  there  is  a  lack  of 
understanding of the potential to reduce energy use or even produce energy partly due 
the  absence  of  systematic  energy  audits  for  the  wastewater  treatment  plants  but  also  at 
the level of the collecting networks.    

Figure 7: Annual electricity used vs size of treatment plants, source: Ganora et al, 2019  

The recent proposal to revise the EED, tabled by the Commission as part of the “Fit for 
55” package, entails the requirement, for large enterprises consuming more than 10 tera-
joules/year, to be subject to energy audits. Most of the wastewater treatment plants would 
however  not  be  covered  by  this  new  obligation,  as  the  average  energy  consumption  of 
large  wastewater  facilities  of  100.000  p.e.  amounts  to  7,2  terajoules/  year  (or  2Mw/h). 
The REFIT evaluation has shown the lack of understanding of the sector on the potential 
energy savings in the treatment facilities and to a certain extent in the collecting systems.    

2.1.2.3 Sludge and water re-use  

Sludge reuse in agriculture is governed by the Sewage Sludge Directive (currently under 
evaluation). The UWWTD contains limited provisions on sludge reuse or recovery14. The 
Evaluation concluded that, currently, sludge management is not optimal and not aligned 
with the principles of the circular economy: today about half of the sludge is reused in 
agriculture while another large part is being incinerated or landfilled representing a clear 
loss of valuable resources, including Phosphorus (see Figure 8). 

A  joint  seminar  was  organised  on  sludge  management  in  the  context  of  the  ongoing 
Evaluation  of the SSD and of this  IA.  It  confirmed that, over the past  years, some MS 
have heavily restricted the use of sludge in agriculture on public health grounds (DE, AT, 
NL, BE), while others do use it extensively. Without additional action to limit pollution 
at source and improve sludge control before its use in agriculture, there is a risk that this 
trend increases in the coming years. Phosphorus could also be easily recovered from the 
ashes of mono-incinerated sludge, but this is not yet current practice in most MS.  

14 MS are ‘incentivised’ to re-use sludge and ‘minimise the adverse environmental effects’ (Article 14). 

24 

 
 
                                                           
Figure 8: Sewage sludge reuse in EU-28 in the period 2012-2016 (% of sewage sludge reused 
in soil and agriculture – source: Annex 10, report 7) 

Water reuse after treatment in wastewater facilities should also be better incentivised: in 
2015, according to the impact assessment on the Water Reuse Regulation, only 2,4% of 
the treated wastewater was reused. In the aggravating climate change context leading to 
more  frequent  instances,  across  the  EU,  of  droughts  and  water  scarcity,  the  entry  into 
application, in 2023, of that new Regulation creates further incentives to reuse water.  

2.1.2.4 Health and wastewaters    

Today there is lack of understanding of the added value of accurate monitoring of public 
health  relevant  parameters  in  urban  wastewaters.  This  is  partly  due  to  the  absence  of 
systematic dialogue and coordination between public health and wastewater authorities. 
The  COVID-19  pandemic  has  revealed  the  added  value  of  tracking  the  virus  and  its 
variants  in  wastewaters.  Such  surveillance  helps  to  anticipate  and  follow  the 
dissemination  of  the  virus  into  the  population.  Today,  with  the  financial  support  of  the 
EU and in line with the 2021 Commission Recommendation on Covid 19, 26 MS have a 
surveillance infrastructure in place. Other types of health parameters could be monitored 
in the wastewaters as a complementary and reliable indicator of the public health state of 
the population.  

Antimicrobial  Resistance  (AMR  –  see  glossary)  is  a  major  human-health  threat 
aggravated  by  the  fact  that,  for  the  time  being,  there  are  no  alternatives  to  antibiotics. 
Wastewater  treatment  plants  are  a  potential  entry  point  of  antimicrobial-resistant  genes 
and  organisms  in  the  environment.  Treatment  plants  may  contribute  to  the  removal  of 
AMR from the effluents. There is no obligation to monitor and remove AMR, neither at 
the outlet of the treatment facilities nor in the receiving water bodies.   

2.1.3 Modernisation and Governance - problem and drivers 

Like drinking water operators, wastewater operators are part of a ‘captive’ market: both 
citizens  and  businesses  connected  to  the  public  network  cannot  choose  their  operators. 
The  Evaluation  and  the  consultation  process  confirmed  that  the  wastewater  sector  is 
mainly  reactive  to  legal  requirements.  Most  competent  authorities  are  implementing 
only the minimum requirements of the Directive. There are indeed few incentives to ‘do 

25 

 
 
better’ beyond such legal requirements, as doing more usually entails additional costs, to 
be  covered  by  water  tariffs  or  further  budgetary  expenditures.  Some  MS  apply  more 
stringent  standards,  for  instance  when  it  is  necessary  to  meet  the  objectives  of  other 
relevant  legal  obligations  such  as  the  Bathing,  Drinking  and  Water  Framework 
Directives, but this is not systematic (see Annex 5).   

2.1.3.1 Operators’ performances and transparency      

A  recent  OECD  analysis  (Annex  10,  report  6)  showed  differences  in  terms  of 
performances between operators in relation to energy efficiency, GHG emissions, social 
and economic governance, operational aspects (see Figure 9). Some of these differences 
can be explained by different operating conditions (facilities size, climatic/geographical 
conditions). Others can only be explained by a sub optimal management due to lack of 
real incentives (‘captive’ market) and/or a lack of technical skills in fragmented utilities. 

Figure 9: Operational costs – EU wastewater operators – OECD (2022), Annex 10, report 6  

The level of transparency also differs from one operator to another: some operators are 
providing detailed information either on the bills, on their web sites or via apps not only 
on their level of performance but also on the main elements included in the  water bills.  
This uneven level of access to information prevents an equal empowerment amongst EU 
citizens. Respondents to the OPC indicated the need for receiving more information. 

2.1.3.2 Uneven application of the ‘polluter pays’ principle 

The lack of the application of the “polluter pays” principle in the water sector was raised 
in a recent report for the Court of the Auditors. In order to cover the costs related to the 
implementation of the Directive, MS are using a mix of public budget and water tariffs. 

26 

 
Many  relied,  and  some  still  rely,  on  EU  funding  to  build  up  the  initial  infrastructure.15  
As  shown  in  Figure  10,  public  budget  covers  around  30%  of  the  expenses  for  water 
supply  and  sanitation  –  the  rest  (70%)  is  covered  by  water  tariffs.  Water  tariffs  are 
usually covering both water supply and sanitation: on average wastewater collection and 
treatment  account  for  about  60%  of  the  water  bill  although  drinking  water  represents 
40%.  

There are large differences between MS: some MS like DK or FI are nearly at full cost 
recovery  through  water  tariffs.  In  these  MS,  the  ‘polluter  pays’  principle  can  be 
considered as respected for households connected to the public network. This is however 
not the case in other MS, such as IE, LU or CY, where less than 22% of the overall costs 
is covered by water tariffs (source: OECD, see Annex 10, report 5). According to OECD 
(see  also  Figure  19),  affordability  is  not  a  major  issue  in  the  EU.  The  effects  of 
additional requirements set at EU level should nevertheless be carefully analysed.   

Contrary  to  households,  the  ‘polluter  pays’  principle  is  not  applied  for  non-domestic/ 
industrial  pollution  gathered  in  public  networks:  so  far  there  is  no  mechanism  to  make 
industrial  producers  financially  responsible  for  the  water  pollution  generated  by  the 
products  they  place  on  the  EU  market.  This  is  the  case  for  instance  for  pollutants  of 
emerging concern such as micro-pollutants or micro-plastics partly collected and treated 
in the wastewater treatment plant without any support from the producers/importers.   

EU-28

EU-15

EU-13

0%

20%

40%

60%

80%

100%

Public budget

Revenues from water tariffs

Figure  10:  Sources  of  financing  for  water  supply  and  sanitation  services  –  EU  28,  Source: 
OECD (2020) – ref in Annex 10, report 5  

2.1.3.2 Not adapted monitoring and reporting  

Monitoring requirements set in Article 15 of the Directive have proven effective to drive 
compliance.  However,  technological  advances  allow  today  for  more  efficient  and 
accurate monitoring of both existing and emerging pollutants. Information gathered from 
MS in the context of this IA (Annex 5) shows that there are large divergences among MS 
in  terms  of  monitoring.  Most  MS  are  already  collecting  more  frequent  and  broader 
information  on  more  pollutants  than  what  is  required  by  the  Directive.16    Yet,  the 
knowledge on the quality and quantity of wastewaters is insufficient in many instances. 
Several  cases  of  over  dimensioning  of  facilities  but  also  storage  capacities  to  reduce 
SWO  and  urban  runoff,  leading  to  excessive  costs  and  inefficient  water  collection  and 
treatment, could have been avoided with a better understanding of the actual load to be 
treated.  

15 Since 2000, € 38.8 billion of cohesion policy funding was allocated to wastewater   
16 For example, the Directive requires only a very limited number of samples even for large facilities. 

27 

 
 
                                                           
Reporting  requirements17  set  by  the  Directive  could  be  improved  and  modernised  to 
ensure a better enforcement of the Directive. Some provisions are by now outdated. This 
is  the case for the  bi-annual  Commission  report  required under  Article 17:  while today 
most  data  are  accessible  in  real  time,  these  reports  are  published  few  years  after  the 
actual monitoring.  Also, precise data  with the numerical  values are  available in  all MS 
although  only  ‘passed/failed’  values  are  reported.  At  the  same  time,  the  Directive  does 
not request reporting on some key data for instance on remaining sources of pollution. 

The bi-yearly requirement to produce national implementation programs under Article 17 
might  be  excessive  for  those  MS  which  have  reached  100%  compliance  with  the 
Directive.  This  information  remains  on  the  contrary  indispensable  for  the  other  MS: 
having  a  proper  investment  planning  combined  with  a  financing  strategy  is  key  to 
achieve  full  compliance.  Also,  the  information  requested  under  Article  17  is  not  fully 
consistent with the ‘enabling condition’ for EU funding under the Cohesion Policy.18  

2.1.3.2 Insufficient access to sanitation   

Access to sanitation remains an issue preventing the EU to fully implement SDG 6 and 
its objective of ensuring ‘access to adequate and equitable sanitation and hygiene for all’: 
the Directive does not require MS to guarantee access to sanitation. In the EU, according 
to  Eurostat,  approximately  2%  of  the  population  have  no  access  to  an  indoor  flushing 
toilet. Around 10 million people living in the EU still lack access to  sanitation services 
(EC,  2020).  According  to  EU  statistics,  10  to  12  million  Roma  people  are  living  in 
Europe, 2.6 million refugees, and 700.000 people sleeping in the rough every night.  

During the consultation it appeared that the problem can be split in 3 parts: 1) vulnerable 
and marginalised people such as homeless ones having no or poor access to sanitation; 2) 
people living in rural areas with a lack of flush toilets and other sanitation facilities; and 
3) cities with insufficient access to public sanitation facilities.  

2.2 How likely is the problem to persist? 

The  Evaluation  has  shown  that  the  ‘carrot  and  stick’  (combination  of  enforcement  and 
support  notably  with  Regional  funds)  approach  followed  by  the  Commission  to  ensure 
the  implementation  of  the  Directive  has  paid  off.  It  had  helped  to  progressively  ensure 
high levels of compliance with the Directive. Yet, in the absence of EU rules combined 
with possible renewed ways of funding the necessary measures, only poor progress can 
be expected at EU level in controlling remaining pollution from remaining urban sources, 
such  as  SWO  and  urban  runoff,  releases  from  smaller  agglomerations,  N/P  or  micro-
pollutant  releases.  Information  collected  for  this  IA  (see  Annex  5)  shows  that  only 
limited or uneven progress were achieved to limit pollution from these sources. 

Urbanisation is expected to progressively modify the needs of wastewater collection and 
treatment: in line with OECD predictions, the trend of urbanisation - people leaving rural 
areas  to  move  in  urban  areas  -  will  continue  in  the  coming  years  which  will  have  an 
effect  on  soil  sealing,  in  turn  potentially  inducing  more  urban  floods  and  SWO.  These 
impacts  might  be  mitigated  by  the  implementation  of  the  Biodiversity  and  the  Soil 
Strategies. Ageing population will lead to an increased use of pharmaceutical products 

17  According  to  the  Directive,  MS  have  to  notify  to  the  Commission  every  two  years  ‘situation  reports’ 
(Article 16) but also their national ‘programme for the implementation of the Directive’ (Article 17).   
18 Enabling conditions for water consist in establishing national investments plans for the water sector.    

28 

 
                                                           
but also to a higher demand for security and control of health risks. With the effects of 
climate change already seen on rainfall regimes, more frequent heavy rains are expected 
which will exacerbate the problems linked with SWO and urban runoff.   

No  major  new  technological  developments  are  expected  in  the  coming  years  for  the 
‘classical’  treatment  processes  of  wastewater.  However,  digitalisation,  permanent 
automated  monitoring  and  instrumentation,  control  and  automation  (ICA)  are 
expected to help in better managing the collection, storage and treatment of wastewater, 
notably for what relate energy use and related GHG emissions. It could also help to avoid 
building larger infrastructures, for instance to tackle the issue of SWO and urban runoff, 
by  optimising  the  infrastructures  in  place.  Digitalisation  will  also  help  rationalise  and 
simplify reporting from the local/national authorities to the EU. New testing techniques 
have the potential to change monitoring and assessment practices and costs in the future. 
Instead of testing for the presence of hundreds of potentially harmful substances, effect-
based monitoring would allow for more targeted monitoring and control measures. This 
might be particularly relevant, for instance, for micro-pollutants.   

In the absence of obligation of energy audits, the lack of understanding of potential for 
implementing  energy  saving  measures  and,  to  a  lesser  extent,  for  producing  renewable 
energies  and  biogas  is  expected  to  persist.  Technological  developments  and  experience 
gained  across  some  MS  (see  Box  1  below)  show  that  there  is  a  potential  for  the 
wastewater treatment sector to become ‘energy neutral’ (see section 5.2.7). 

3.  WHY SHOULD THE EU ACT? 

3.1 Legal basis 

The current UWWTD is based on Article 192(1) of the Treaty on the Functioning of the 
European Union (TFEU), which states that “Union policy on the environment shall aim 
at a high level of protection taking into account the diversity of situations in the various 
regions  of  the  Union.  It  shall  be  based  on  the  precautionary  principle  and  on  the 
principles that preventive action should be taken, that environmental damage should as a 
priority  be  rectified  at  source  and  that  the  polluter  should  pay”.  Action  in  the  field  of 
wastewater management must therefore be taken according to these key provisions and in 
the  respect  of  the  shared  competence  with  the  MS.  This  means  that  the  EU  can  only 
legislate  with  due  consideration  for  the  principles  of  necessity,  subsidiarity  and 
proportionality. 

3.2 Subsidiarity: Necessity of EU action 

The Evaluation confirmed the added value of the Directive and found that EU action was 
and  is  necessary  to  achieve  a  high  level  of  environmental  and  human  health  protection 
via  a  sound  wastewater  management,  as  the  vast  majority  of  MS  would  have  not 
achieved  the  same  results  on  their  own.  This  is  confirmed  by  the  results  of  the  OPC 
suggesting that continued action  from  the EU is considered necessary to ensure further 
progress. The incentive to reinforce and improve the level of environmental and health 
protection linked to wastewater management is indeed limited as it is directly linked with 
additional  costs  for  operators,  users  and/or  national  budgets.  As  explained  above,  the 
wastewater sector is mainly responsive to EU legislation on which national legislation is 
based. Without EU intervention, only modest new progress is expected.  

29 

 
 
Transboundary rivers cover 60% of the EU – the impacts of discharges in one MS will 
directly  affect  the  environment  in  other  MS.  It  is  therefore  indispensable  to  ensure 
simultaneous efforts in all MS with a same level of standards for wastewater collection 
and treatment.  That  will avoid  that efforts made by some MS are partly jeopardised by 
the lack of investments in others MS. Such an approach cannot be ensured at MS level 
alone.    

The  Evaluation  also  confirmed  that  the  EU  action  has  ensured  and  has  a  potential  to 
further ensure an equal level of environmental and human health protection across all 
Member  States.  More  than  half  of  respondents  to  the  OPC  across  all  stakeholder 
categories  rated  the  risk  perception  of  pollution  from  untreated  wastewater  as  a 
significant  concern.  There  was  consensus  among  respondents  on  addressing  all 
contaminants listed in the survey (corresponding to the pollutants addressed in this IA). 
Over the last 30  years of implementation of the UWWTD, the quality of bathing water 
sites (hence tourism and recreation), raw water used for the production of drinking water 
and  of  water  bodies  in  general  has  been  either  preserved  or,  in  several  instances, 
improved (see section 5.1 of the Evaluation of the Directive). Similarly, making sure that 
key health parameters are tracked in wastewaters will increase the health protection of 
all EU citizens. Improving access to sanitation but also empowering all EU citizens by 
ensuring  an  equal  access  to  information  should  be  ensured:  the  Evaluation  has  shown 
large  differences  among  EU  citizens,  from  that  perspective.    All  MS  are  facing  the 
consequences of climate change notably on their hydrological regimes and urban micro-
climate.  Similarly,  pollutants  of  emerging  concern  such  as  micro-pollutants  or  micro-
plastics are present in all MS. This is also the case for most of the remaining loads from 
urban  sources  which  affect  water  quality  in  all  MS.  Also,  the  drivers  for  the  identified 
problems are very similar from one MS to another.   

3.3 Subsidiarity: added value of EU action 

As  shown  in  the  Evaluation,  EU  action  remains  essential  to  ensure  that  benefits  from 
improved  water  quality  of  the  EU  rivers,  lakes,  ground-waters  and  seas  are  optimised. 
Experts consulted as part of the evaluation agreed on the decisive role that the UWWTD 
had in establishing collection and treatment infrastructures. EU action ensures that water 
bodies  benefit  from  the  same  level  of  protection  at  the  same  time.  Without  EU  action, 
part of the efforts made by some MS at national and local level could be overridden by 
lack of progress of the others. This is valid not only for transboundary water bodies but 
also inside MS as, for most of them, the Directive was the key driver for investing in the 
required infrastructures.   

The Evaluation showed that EU standards were a crucial driver for the development of a 
globally  competitive  EU  water  industry.  Since  the  adoption  of  the  Directive,  several 
major worldwide leaders in the field of wastewater treatment have been created and are 
exporting their services all around the world. Further modernising the EU standards, for 
instance  with  new  requirements  on  micro-pollutants  or  energy  use  would  further 
stimulate innovation and ultimately economies of scale. This is also the case if, in line 
with the objectives of the Green Deal and the EU Climate Law, common efforts are taken 
to improve energy efficiency, develop renewables and produce more biogas in the sector.  

Establishing  new  rules  in  application  of  the  “polluter  pays”  principle  particularly  for 
micro-pollutants should be done at EU level to avoid market distortion. Also, given the 
multiplication of national standards (see section 2.1.1.3), adopting EU standards for IAS 

30 

 
 
will  limit  barriers  to  the  internal  market.  Ensuring  harmonised  approaches  for  the 
remaining loads identified in section 2.1 will help develop common approaches, favour 
the development of new skills and new markets. For instance, applying best practices at 
EU  level  for  storm  water  overflows  and  urban  runoffs  would  lead  to  better  urban 
planning,  the  development  of  nature-based  solutions,  full  use  of  digitalisation  and 
optimisation  of  existing  infrastructures.  This  will  require  new  competences  and  create 
new market opportunities. This is also the case for other aspects such as energy and GHG 
reduction.  

The  recent  pandemics  has  shown  the  interdependence  of  the  MS  in  terms  of  virus 
circulation. Ensuring an effective, rapid,  and harmonised tracking of pathogenic factors 
in wastewaters can benefit the whole EU. Without EU harmonised and integrated action, 
the  possibilities  of  tracking  new  types  of  viruses  but  also  of  surveying  other  relevant 
health parameters in wastewaters would only be achieved in a few, most advanced MS.  

4.  OBJECTIVES: WHAT IS TO BE ACHIEVED? 

4.1 General objectives 

The main objective of the initiative is to contribute, in an effective and efficient way, to 
protecting  the  environment  and  human  health  from  the  adverse  effects  of  urban 
wastewater discharges. The aim is to modernise the legislation by adapting it to current 
and future societal needs while adapting it to the objectives of the European Green Deal 
and  of  a  Europe  fit  for  the  Digital  Age.  There  was  a  broad  consensus  amongst  the 
stakeholders  regardless  their  background  on  the  key  objectives  for  this  review.  The 
Evaluation  highlighted  that,  according  to  business  and  WWTP  operators,  the  Directive 
does not sufficiently deal with resource recovery and emerging pollutants. Stakeholders 
also  insisted  on  the  necessity  to  give  predictability  to  the  sector  with  clear  legal 
requirements for the next decades – so that the necessary investments can be planned on 
due time.   

The planned EU intervention would have two main general objectives: 

1.  To protect EU citizens and ecosystems from the remaining sources of insufficiently 

treated wastewater;  

2.  To  provide  a  predictable  framework  for  the  sector,  improve  its  transparency  and 

governance and align it to “a Europe fit for the Digital Age”;  

and two complementary objectives: 

3.  To  align  the  sector  to  the  objectives  of  the  Green  Deal  and  the  recently  adopted 
Communication  ‘Repower  EU’,  regarding  in  particular  the  2050  goal  of  climate 
neutrality in synergy with the ESR, transition to circular economy, zero pollution and 
a restoration of biodiversity;  

4.  To  use  wastewater  health  related  parameters  as  a  support  for  public  health  and  to 
improve ‘adequate and equitable sanitation and hygiene for all’ in line with SDG 6. 

4.2 Specific objectives 

The following achievements should be met in an effective and efficient way:  

In relation to objective 1:  

31 

 
  Contribute to identifying and then preventing pollution reaching wastewater 

treatment plants with particular attention to pollutants difficult to treat in these plants; 
  Further reduce pollution from the ‘remaining sources’ (storm water overflows, urban 

runoff, smaller agglomerations and IAS);  

  Further reduce nutrient (N and P), micro-pollutants and micro-plastics pollution from 

urban sources; 

  Reinforce the coherence with key EU water legislations (such as the Bathing Water, 

Water and Marine Framework Directives and the Drinking Water Directive);  

  Encourage investment and innovation in wastewater management. 

In relation to objective 2:  

  Ensure high level of transparency and access to information;  
  Ensure that investments are taking place ‘where it makes sense’ for environmental or 

health reasons (based on clear criteria);  

  Promote a solid financing strategy while ensuring affordability of water tariffs and 

better applying the ‘polluter pays’ principle besides household users;    

  Modernise, simplify and adapt monitoring and reporting obligations. 

In relation to objective 3:  

  Move towards energy neutrality of wastewater sector;   
  Create the conditions for increasing water reuse and better managing sludge and 

waste, in close synergy with the new Water Reuse Regulation, the Sewage Sludge 
Directive and the EU waste acquis. 

In relation to objective 4:  

Improve access to sanitation particularly for vulnerable and marginalised people;   

 
  Ensure that health relevant information from wastewaters is fully used;  
 
  Better monitor the spreading of AMR in wastewaters and prevent its dissemination.   

Improve the dialogue between health and wastewater competent authorities;  

Two  main  trade-offs  between  these  objectives  will  require  particular  attention:  (1) 
additional treatment for micro-pollutants will require more energy and, if this energy is 
coming from non-renewable sources, this will entail more GHG emissions; (2) increasing 
our  understanding  on  some  key  sources  of  pollution  as  well  as  on  some  key  indicators 
will  require  additional  efforts  and  might  increase  the  administrative  burden  related  to 
monitoring and reporting. At the same time, there is a potential to simplify some of the 
current requirements. These aspects are further discussed in sections 5 and 6.   

Respondents to the OPC provided clear indications on the main objectives and topics the 
revised  legislation  should  address.  Better  implementing  the  polluter  pays  principle 
was  indicated  as  the  most  important  topic,  followed  by  promoting  the  monitoring  of 
industrial releases into urban wastewater, reducing nutrient discharge into water bodies, 
and  dealing  with  SWO  and  urban  run-off  through  an  integrated  approach.  All  are 
addressed in the specific objectives set for the intervention. 

32 

 
The  relation  between  the  problems,  their  drivers,  the  objectives  and  the  options  are 
summarised  in  Figure  11  below  although  more  details  on  the  relation  between  the 
problems,  drivers,  options  and  their  contribution  to  specific  objectives  is  provided  in  
Figure 14 below.  

33 

 
Drivers 

Climate change and 
urbanisation      

Small agglo out of the 
Directive, unclear requirements 
and unjustified use of IAS in 
large agglo  
Unclear criteria for ‘sensitive 
areas’ and outdated standards 
for N & P 
Ageing population  and  
Increasing use of 
pharmaceuticals and personal 
care products 
Insufficient control of non-
domestic pollution 

Poor awareness/understanding 
on GHG emissions and energy 
potential savings 
Captive market, no incentives 
to ‘do better’ 
No tradition of producer 
responsibility schemes for  
water pollution  
Inadequate monitoring 

Non digitalised reporting 

Access to sanitation not in the 
scope of the Directive 

Poor coordination between 
public health and wastewater 
competent authorities   

Problems 

Objectives 

Options 

To protect EU citizens 
and ecosystems from 
the remaining sources 
of insufficiently 
treated wastewater 

To align the 
wastewater sector to 
the objectives of the 
Green Deal (climate 
neutrality in 2050, 
transition to circular 
economy, zero 
pollution and 
restoration of 
biodiversity) 

To provide a 
predictable 
framework for the 
sector, improve its 
governance and full 
use of digitalisation  

To improve access to 
sanitation and to use 
wastewater health 
related parameters to 
prevent and manage 
public health issues 

Increasing pollution from 
SWO/urban runoff 

Remaining pollution from 
small agglo and non-
compliant IAS 

High level of N & P releases 
leading to Eutrophication 

Increasing releases of  micro-
pollutants 

Poor actions to reduce 
pollution at source, limited 
sludge/water reuse 
High energy use with high 
costs and high GHG 
emissions    
Diverging operator 
performances  
Insufficient application of the 
‘polluters pays principle‘ 

Lack of knowledge on 
remaining sources of 
pollution, poor data on actual 
performances  
Outdated reports, admin 
burden 
Poor access to sanitation for 
some EU citizens contradict 
SDG 6   

Under use of health 
indicators (notably on Covid 
and Anti- Microbial 
Resistance - AMR) 

SWO and urban runoff 
 

Set of measures applied from large agglomerations above 100.000 pe  
(low ambition) to lower agglomerations 10.000 pe  (high ambition)  

  Measures includes integrated management plans and monitoring 
Small agglomerations 
  Review of the threshold (from 500 to 1.000 pe) 
Individual Appropriate System 
  Better control of the IAS combined with EU clear standards 
Nutrients 
 

Set of options from low ambition (N/P removal applied only to facilities above 100.000 pe) to 
high ambition (N/P removal above 10.000 pe combined with stricter standards for N/P removal)  

  Clarified criteria for designating sensitive areas   
Micro-pollutants 
 

Improved monitoring of incoming waters in the treatment plants  

Energy audits and monitoring 
Energy neutrality by 2040 leading to GHG emission reduction  

Set of options from low ambition (micro-pollutant removal applied only to facilities above 
100.000 pe) to high ambition (all facilities >10.000 pe)  
  Medium option based on risk assessment (dilution rates)    
  Application of the Extended Producer Responsibility 
Non domestic emissions 
 
GHG and Energy 
 
 
 Governance  
  Monitoring performance indicators 
 
Monitoring & Reporting 
  Digital monitoring/reporting 
  Adaptation of monitoring requirements to remaining sources of pollution 
 
Access to sanitation 
 
  MS to improve access to sanitation  
Health 
 

Sampling & analysis COVID-19 and its variants/AMR 

Identification of marginalised and vulnerable people 

Increased transparency for water users 

Simplified reporting  

Figure 11: Links between drivers, problems, objectives and options 

34 

 
 
 
 
 
 
 
 
5.  WHAT ARE THE AVAILABLE POLICY OPTIONS? 

5.1 What is the baseline from which options are assessed? 

The baseline scenario implies the progressive achievement of full compliance by all MS. 
In  designing  the  baseline,  it  is  assumed  that  the  identified  problems  would  remain, 
although their scale would be impacted by external trends such as urbanisation, changes 
in demographics, changes due to climate impacts (e.g. more intense rains and storms), the 
development  of  new  technologies  (see  section  2.2).  The  ‘domestic’  pollution  (BOD,  N 
and P, E. coli) is expected to remain globally stable as it is mainly linked to the evolution 
of  the  population  connected  to  the  network:  EU  population  is  expected  to  slightly 
increase  (0,2%)  by  2035  and  then  decrease  (1,36%)  by  2050.19  These  changes  do  not 
require  a  significant  adaptation  of  the  usually  slightly  oversized  infrastructure.  At  the 
local scale, though, there might be needs for adjustment.  

EU actions to limit pollution at source might have an effect on the other (‘non domestic’) 
pollutants reaching treatment plants and on the quality of the sludge produced afterwards. 
The impacts might be significant for some substances in case they are fully banned from 
the  EU  market.20  Progress  is  also  expected  from  the  implementation  of  the  2020 
Chemical,  Pharmaceutical  Strategies  and  the  2021  Zero  Pollution  Action  Plan.  This 
progress is however difficult to quantify at this early stage. In any event, actions will be 
required both at source and in wastewater treatment plants, for instance to prevent micro-
pollutants  to  reach  receiving  waters.  Several  measures  are  also  envisaged  to  reduce 
micro-plastics at source – see Annex 10, report 3. In the absence of final decisions, at this 
stage, on their exact extent, it has not been possible to quantify their possible effects.  

In  the  baseline,  for  wastewater  treatment  in  centralised  facilities,  full  compliance  was 
assumed with differentiated dates according to the distance to target of each MS (Table 
A7-1,  Annex  7)21.  On  top  of  the  key  support  from  regional  funds,  some  MS  are 
benefiting from the Technical Support Instrument for their water sector. The Commission 
with the OECD is also providing tailored support to MS (see Annex 10, report 5).   

For  Individual  and other  Appropriate Systems  (IAS), the effects  of full implementation 
were included in the baseline: it was assumed that all IAS would have an equivalent level 
of  treatment  as  required  by  the  Directive.  Additional  initiatives  further  discussed  in 
sections 5.2 and 6 would be needed to ensure full implementation. According to the data 
gathered  in  the  context  of  this  IA  (see  Annex  4  and  5),  today  67%  of  MS  are  treating 
wastewaters  from  small  agglomerations  below  2.000  p.e.  to  the  level  of  secondary 
treatment, 26% to the level of primary treatment and 7,4% is considered as not treated. 

The effects of the baseline are summarised in Table 2 below and illustrated in Figure 1. 
Full compliance with the existing legislation would reduce the remaining loads emitted to 
the  environment  by  21,4%  for  BOD,  6,3%  for  N,  13,4%  for  P,  21,9%  for  E.  coli  and 

19  According  to  Eurostat,  total  EU  population  is  expected  to  increase  from  447.319.916  (2020)  to 
448.233.662 (2035) and then decline to 441.220.961 by 2050 
20 This might be the case for some harmful substances such as PFAS, intentionally-added micro-plastics in 
some products such as paints, PCP’s, or mercury in dental amalgams 
21  8  MS  are  fully  compliant  today  (with  less  than  1%  distance  to  target),  15  other  MS  are  expected  to 
become fully compliant within the next 3 years. Full compliance was assumed by 2028 for RO, SI, MT and 
by 2031 for BG (Annex 10, report 1). 

35 

 
                                                           
4,2% for micro-pollutants. The bulk of the effects of the baseline scenario would appear 
by 2025 (when 23 MS are expected to become fully compliant), with full effects by 2031.  

BOD 

N 

P 

E. coli 

Micro-
pollutants 

Current (p.e.) 

66.148.823 

191.126.725 

148.600.784 

71.110.762 

264.127.257 

Baseline (p.e.) 

51.966.775 

179.087.499 

128.621.614 

55.510.146 

252.954.625 

Current situation 
(Tons/year) 
Baseline 
(Tons/year) 

1.448. 659 

779.711 

91.122 

1.138.072 

730.802 

78.871 

- 

- 

- 

- 

Table 2: Summary of the of the baseline scenario (full compliance) – remaining loads per year 
emitted to environment – A breakdown per MS is provided in Annex 7, Table A7.6 

In terms of energy use and GHG emission reduction, progress could be expected from the 
combined application of the Fit for 55 package, the EED, the RED II, the ESR and the 
very  recently  adopted  RePowerEU  package  (see  Annex  8).  In  the  context  of  this  IA, 
efforts were made to build a dynamic scenario taking into account the potential effects of 
these legislations and policy packages on energy use and GHG emission reductions:  

  The  recently  adopted  RePowerEU  Plan  aims  at  rapidly  reduce  dependence  on 
Russian fossil fuels and fast forward the green transition. Several actions are included 
in  the  Plan  notably  to  promote  renewables  including  the  production  of  biogas.  No 
specific quantifies targets per sector are included in the Plan making it impossible to 
quantify its possible effects on the wastewater sector;   

  Under the Fit for 55 package, the EED, the RED II and the ESR, MS have to meet 
national targets (see Annex 8 for more details) and can choose in which sector efforts 
will be made to meet these targets. There is no sufficiently detailed data on how MS 
intends  to  meet  these  targets  with  a  sufficient  level  of  disaggregation  to  identity  to 
what  extent  the  wastewater  sector  would  be  included  or  not  in  MS  efforts.  It  is 
therefore  not  possible  to  quantify  the  effects  of  national  based  targets  on  the 
wastewater treatment sector. A few MS (like DK and NL  – see Box 1 below) have 
well understood the high potential of the sector but so far they remain an exception. 
The starting position of the other MS is largely unknown in absence of any reporting 
obligations  on  energy  use  and  production  of  renewables  from  this  sector.  The 
potential  impacts  of  these  uncertainties  are  summarised  in  Table  18.  In  summary, 
those  MS  using  more  energy 
their  wastewater  operations  will 
today  for 
proportionally  benefit  more  from  systematic  energy  audits  and  the  related 
investments  in  energy  efficiency  and  production  of  renewables.  These  investments 
will be more significant in these countries but also more profitable.  

  Nevertheless, as detailed in the recast EED, the public sector should lead by example, 
and  therefore  a  specific  mandatory  target  was  introduced  for  all  public  bodies 
which covers the  wastewater sector (1.7% per  year reduction of energy  use starting 
by 2025).  

In the baseline, this mandatory target was therefore applied. As shown in  Table 3 below, 
a reduction of energy use of 1,7% per year from 2025 was included in the Baseline. This 
would represent a reduction of 25,5% of the energy used by 2040 compared to 2025. 
This will have a direct effect on GHG emission reduction, which was taken into account 
in  the  baseline:  around  1,19  million  tons  of  GHG  would  be  avoided  thanks  to  the 
implementation  of  the  EED.  This  represents  11,89%  of  the  ‘avoidable  emissions’  and 
will generate a monetised benefits of 118,9 million € per year by 2040. This assumption 

36 

 
  
 
is  based on a (future) legal  obligation which is  the most solid  basis to  build a dynamic 
baseline,  but  as  explained  above,  there  are  uncertainties  which  are  further  discussed  in 
section 7.1, Table 17.    

  Emissions 
of GHG  
(million tons 
CO2e/year 
per year)    

Expected 
energy 
savings 
(based on 
1,7% 
reduction per 
year) 

GHG 
emission 
reduction 
(million tons 
CO2e/year) 

% of 
avoidable 
GHG 
emissions  

Monetised 
benefits 
(million 
€/year)    

Current situation 

34.6 

- 

- 

- 

- 

Baseline  

33.34  

25,5%  

1.188.477 

11,85% 

118,9 

Table 3: Baseline scenario – impacts of the EED on the energy use and GHG emissions  

5.2 Description of the policy options 

Several  policy  measures  addressing  each  identified  problem  have  been  retained  for 
further analysis. For each problem, different solutions were envisaged, ranging from soft 
approaches  -  mainly  based  on  non-binding  guidance  to  MS  -  up  to  stricter  regulatory 
measures.  There  are  limited  interactions  among  the  proposed  solutions,  which  will  be 
clearly identified in the following sections.  

The measures detailed below are based on what is already in place in the most advanced 
MS22.  As  shown  in  the  Evaluation,  having  in  place  enforceable  measures  was  a  key 
element  for  the  success  of  this  Directive.  Therefore,  too  complex  measures  difficult  to 
control  were  avoided.  Also,  in  the  initial  screening,  measures  which  were  not  broadly 
supported by stakeholders or identified as good practice were discarded.   

For some problems, the analysis and experience confirmed also by a consensus across the 
stakeholders groups show that only a limited set of measures is available without real 
alternatives. This is the case for non-domestic waters, some aspects of governance such 
as  transparency,  access  to  sanitation  or  public  health  indicators.  For  other  problems, 
different  options  from  low  to  high  level  of  ambition  were  tested  to  find  optimal 
solutions.  This  is  the  case  for  SWO  and  urban  runoff,  small  scale  agglomerations, 
nutrients and micro-pollutants abatement. The lowest ambition options would apply only 
to  a  limited  number  of  large  facilities  or  agglomerations  although  the  highest  ambition 
options would apply to more and smaller facilities and agglomerations.     

To fix adequate thresholds for the different options, the share of the treated load amongst 
the  different  sizes  of  facilities  and  agglomerations  is  an  important  factor:  81%  of  the 
load is treated in 9% of the EU facilities and agglomerations above 10.000 p.e. – see 
Figure 12  (and Tables A7.3 and A7.4 in Annex 7 for more details). Around 47% of the 
load  is  treated  in  1.3%  of facilities  and  agglomerations  above  100.000  p.e.  There  are 

22 A lot of information on the practices in place was gathered: detailed pre-filled questionnaires were sent 
to all MS summarising their starting position and the data used in the model. All MS provided additional 
data (see Annex 5). Specific technical seminars on each problem identified were organised (see Annex 2). 

37 

 
 
 
 
 
                                                           
minor differences between the number of facilities and agglomerations23 which was taken 
into account when designing the options and assessing their impacts.  

A description of the options considered for the individual problems is provided below. 

Treated Load, Number of facilities  

250.000.000

200.000.000

150.000.000

100.000.000

50.000.000

0

35.000

30.000

25.000

20.000

15.000

10.000

5.000

0

Below
1.000

1001 -
2000

2001 -
10.000

10.001 -
100.000

100.001 -
1.000.000

Above 1
M

Treated load (pe)

Number of facilities

Figure 12: Treated load, number of treatment plants per category (JRC 2022, Annex 4) 

5.2.1 Storm water overflows (SWO) and urban runoff  

The choice of effective measures to control pollution from SWO and urban runoff during 
rainfall events depends on the local conditions.24 Therefore, in line with the principle of 
subsidiarity and proportionality, imposing detailed EU standards constraining the design 
of solutions would not be appropriate.  

Results of the stakeholder consultation identified ‘integrated urban water management 
plans’  established  at  local  level  as  the  right  instrument  to  identify  and  implement  the 
most  cost-effective  local  combination  of  measures.  This  approach  is  already  applied  in 
some MS (such as FI, DE, AT or FR).  

Different levels of ambition were tested to reduce emissions from SWO and urban runoff 
in terms of agglomerations that would be covered:    

-  A low ambition - Option 1, with measures only in agglomerations >100.000 p.e. with 

a focus on agglomerations ‘at risk’;25  

-  A high ambition - Option 3 applied to all agglomerations above 10.000 p.e.;   

-  Several ‘in between’ options were modelled of which a representative Option 2 will 
be presented in section 6 where measures are applied to all ‘at risk’ agglomerations 
above 10.000 p.e.  

23  An  agglomeration  can  include  more  than  one  facility  although  a  facility  can  cover  more  than  one 
agglomeration. The differences are nevertheless marginal – see Annex 7.  
24 Including climatic and geographical conditions, separate or combined collection, storage capacity in the 
network, capacity of the treatment plants to treat rain waters 
25  Agglomeration where due to SWO and urban run-off there is a risk of not achieving the objectives of 
other legislation and notably the DWD, the BWD or the WFD – see section 2.1.1.2 

38 

 
 
                                                           
The  plans  would  include  an  analysis  of  the  initial  conditions,  a  definition  of  the 
objectives,  an  analysis  of  different  scenarios  to  meet  the  objectives  based  on  an 
optimisation of the measures to be taken and defined in the plan. The introduction of the 
plans was generally supported by stakeholders, especially based on the views expressed 
during  the  workshops  and  in  the  OPC.  In  the  targeted  consultation,  where  respondents 
had to  rate propositions  on a scale of 1 to  5, the strategic planning approach was  rated 
high  -  academia  (4.4),  citizens  (4.2),  NGOs  (4.7),  businesses  (4.3),  public  authorities 
(3.6).  Moreover,  there  was  a  consensus  amongst  stakeholders  (academia  (4.7),  citizens 
(4.4),  NGOs  (5.0),  businesses  (4.5),  public  authorities  (4.1))  on  the  following 
combination of measures to be considered in the plans:   

-  Taking  all  possible  measures  to  prevent  the  entry  of  ‘unpolluted  rain  waters’  in 
the wastewater collection network via actions aimed at infiltrating the runoff directly 
onto pervious surfaces, at removing soil sealing and at increasing the runoff retention 
also through nature-based solutions (e.g. green roofs, green urban surfaces);    

-  Measures  to  buffer  polluted  storm  water  flows  within  the  existing  treatment 
infrastructure, by optimizing the use of existing storage volumes e.g. through RTC 
of their operation and, when necessary, by building additional storage volume; 

-  Measures  to  mitigate  the  impacts  from  untreated  water  discharges,  such  as  further 
treatment through nature-based or mixed systems, including constructed wetlands.   

Effective monitoring of the network, linked with a modelling of urban water systems is 
key  in  order  to  optimise  new  investments,  and  indispensable  for  RTC.    Very  recent 
information  (see  Annex  10,  reference  21)  based  on  an  analysis  of  several  case  studies 
shows that significant costs savings (on average 21,4%) can be made with a combination 
of real time control and digitalisation of water management in the cities.  

Mixed views were expressed by stakeholder on the added value of setting an EU based 
objective.  At  least  an  indicative  objective  is  nevertheless  indispensable  to  give 
consistency  and  added  values  to  the  integrated  management  plans.  Based  on  the 
experiences and objectives in place in MS, but also on expert judgement on what is “as 
low  as  reasonably  achievable”  (see  Annex  10,  reports  17  and  18  for  more  details),  a 
maximum load of 1% of the total sewage produced in a catchment served by combined 
sewers (or 1% of the annual total ‘dry weather’ load) was applied as an EU objective for 
the model calculations detailed in section 6.1.  

5.2.2 Small Agglomerations  

To  better  tackle  the  pollution  from  smaller  agglomerations,  the  scope  of  the  Directive 
could  be  expanded  to  include  agglomerations  below  2.000  p.e.  Two  different  options 
based on lower thresholds for the agglomerations were  assessed (1.000  – Option  1 and 
500 p.e. – Option 2).  

The thresholds to be tested were identified on the basis of the share of the remaining load 
according to the size of the agglomerations – see Figure 14: below 500 p.e., the load is 
relatively  low  for  a  high  number  of  agglomerations,  and  above  1.000  p.e.  the  potential 
pollution reduction would not be too limited in comparison to the baseline.   

39 

 
  
Figure 13: Agglomerations below 2.000 p.e. and population (P), source JRC, ref in Annex 10, 
report 10  

18  MS  have  already  decided  to  impose  collection  and  treatment  for  smaller 
agglomerations although others are less active in these areas (ref in Annex 10, report 1). 
As  explained  in  section  5.1,  this  was  taken  into  account  in  the  baseline.  Stakeholders 
were broadly in favour of covering smaller agglomerations in the Directive.  

5.2.3 Loads from individual or other appropriate systems (IAS) 

There  was  a  broad  consensus  among  stakeholders  on  the  need  to  take  the  following 
additional measures (without real alternatives) to ensure a full application of the existing 
Directive  (ensuring  the  ‘same  level  of  treatment’  in  IAS  compared  to  centralised 
facilities):    

  Establish  clear  standards  in  relation  to  emissions  from  IAS  compatible  with  the 
Directive’s requirements and supplementing the standards defined in the Construction 
Product  Regulation  which  was  specifically  supported  by  academia  (4.8).  This 
measure  was  rated  3.8  by  businesses,  4.2  by  citizens  and  NGOs  and  3.5  by  public 
authorities);  
Improve the control of IAS at local level, including through a systemic inventory of 
the  IAS,  regular  inspections  of  the  larger  ones,  an  obligation  of  maintenance.  This 
measure was rated 4.5 by academia, 3.6 by businesses, 3.8 by citizens, 4.1 by NGOs 
and 3.2 by public authorities. 

 

5.2.4 N and P releases and eutrophication  

Different options to reduce Nitrogen and Phosphorus releases were tested: 

-  A low ambition (Option 1) in which N/P removal would be systematically imposed 

only in larger facilities above 100.000 p.e.;   

-  A high ambition (Option 5) in which N/P removal would be systematically imposed 
in all facilities above 10.000 p.e. while N/P removal efficiency would be increased;  

40 

 
 
  
  
-  A  set  of  medium  ambition  (Options  2,  3  and  4)  in  which  N/P  removal  would  be 
imposed to different areas (from the whole territory to only ‘sensitive’ areas subject 
to  eutrophication)  for  different  size  of  facilities  and  with  different  levels  of  N/P 
efficiency. The most representative options are discussed in section 6 and more detail 
can be found in report 15, Annex 10.    

These  options  are  in  line  with  the  measures  identified  in  the most  advanced  MS.  Also, 
there was a consensus across the different stakeholder groups on the fact that current N/P 
standards  could  be  adopted  to  the  performance  actually  achieved  in  well  operating 
facilities  (data  from  the  MS  shows  that  well-functioning  facilities  can  reach  85% 
reduction for N and more than 90% for P - see report 15 in Annex 10). In many cases, the 
plants  can  be  upgraded  with  limited  additional  costs  or  only  through  better  operation 
achieved  with  instrumentation,  control  and  automation  (ICA).  In  some  limited  cases,  it 
would require infrastructural overhauls (all included in the cost assessment - see section 
6.4).   

Overall, stricter N/P emission requirements were supported by stakeholders. Introducing 
the  obligation  to  remove  N/P  to  a  larger  range  of  UWWTPs  was  supported  by  NGOs 
(4.0),  academia  (4.0),  and  businesses  (3.1).  However,  businesses  noted  that  such 
obligations should only be placed for plants above a certain threshold. Public authorities 
seemed least  in  favour of such an option (3.5), and generally showed more support for 
options  on  providing  EU-level  guidance  on  how  to  designate  sensitive  areas  (3.8). 
Stakeholders also supported more clarity on the criteria for the designation of ‘sensitive’ 
areas subject  to  eutrophication but  also  more coherence with  the Nitrate and the WFD. 
This measure was rated 4.5 by academia, 4.1 by citizens and businesses, 4.2 by NGOs, 
and 3.6 by public authorities. 

5.2.5 Micro-pollutants  

Based  on  the  share  of  the  load  between  the  different  facility  sizes  and  on  the  dilution 
rates of the receiving bodies (see Annex 4), the following options were defined:  

  a “low ambition” Option 1 requiring treatment only for large plants (> 100.000 p.e.); 

  a “high ambition” Option 3 requiring treatment for all plants above 10.000 p.e. when 

the dilution ratio is 100 or less; 

  other ‘in between’ options combining size and dilution rates (Option 2 in section 6).  

There was a broad consensus amongst stakeholders on the necessity to address the issue 
of  micro-pollutants 
(PCP’s, 
Pharmaceuticals),  citizens  (4.0),  NGOs  (4.1),  academics  (3.8),  public  authorities  (3.4) 
and  water-related  business  support  the  requirement  for  larger  UWWTPs  to  remove 
micro-pollutants based on EU-set performance standards.   

from  wastewaters.  Contrary 

some  business 

to 

Stakeholders were also insisting on the importance of measures to be taken at source but 
also on the need to better apply the ‘polluter pays’ principle by making the producers 
financially  responsible  for  the  costs  linked  to  the  additional  treatment  required  to  treat 
micro-pollutants. The EPR approach received a broad support (regarding feasibility and 
effectiveness)  from  the  majority  of  stakeholders  (academia  (4.5),  citizens  (4.5),  NGOs 
4.8), public authorities (4.2), including businesses (3.9) except from  the pharmaceutical 

41 

 
 
and chemical industries globally not in favour of such a system, notably on the grounds 
that the financial responsibility should be either shared by all actors involved in the chain 
(from  industry  to  consumers)  or  taken  by  the  public  authorities.  The  feasibility  and 
impacts of a system of producer responsibility was assessed through a specific study (see 
Annex  10,  report  2).  To  be  noted  that  such  a  system  will  de  facto  lead  to  a  shared 
financial responsibility as - depending on the decision to be taken by responsible industry 
- part of the costs will be supported by consumers (see section 6.5).    

5.2.6 Non-domestic emissions  

As detailed in section 2.1.17, the lack of knowledge of the quality of the incoming waters 
of  the  wastewater  treatment  plants  prevents  competent  authorities  to  take  additional 
actions  to  limit  pollution  at  source.  To  improve  the  understanding  of  non-domestic 
emissions sent in the wastewater collection systems, the following actions were identified 
based on the consultation and best practices identified in MS:      

  Expand the scope of pollutants to be regularly monitored at the inlet and outlet of the 
wastewater  treatment  facilities  to  improve  the  understanding  on  the  presence  of 
potentially  harmful  pollutants;  the  list  of  pollutants  should  be  aligned  with  the 
existing  and  soon  to  be  revised  EQSD  and  with  relevant  parameters  listed  in  the 
upcoming revision of the IED and E-PRTR Regulation;   
Incentivise  competent  authorities  to  better  ‘track’  pollution  at  source  based  on 
improved monitoring, particularly when sludge and treated water are re-used;   

 

  Ensure  the  involvement  and  access  to  information  for  wastewater  operators  in 
relation  to  the  discharge  permits  given  to  business  facilities  connected  to  the 
treatment plants via the public collection network, and ensure full coherence between 
the IED and the UWWTD to prevent releases of not abated pollutants in  the public 
network. 

independently  from 

Stakeholders 
these  measures  and 
particularly as regards the necessity to better monitor/understand non-domestic pollution 
entering the treatment plants (one of the top ranked concerns that needs to be addressed).       

their  category,  supported 

5.2.7 Energy     

Based on the experience of the most advanced MS (see Box 1) and the inputs provided 
during the stakeholder consultation, moving toward energy neutrality was identified as a 
promising  avenue  for 
indeed  specific 
characteristics which would justify a specific sectoral target:  

the  sector.  The  wastewater  sector  has 

  The sector today accounts for 0.8% of the overall energy used in the EU and offers 
the  potential  to  significantly  reduce  its  own  energy  consumption,  but  also  to 
produce renewable energy;   

  Wastewater treatment plants are indeed producing a constant flow of sludge which 
after digestion are producing renewable biogas which can be used as a substitute to 
natural gas;   

  Wastewater  treatment  plants  occupy  large  surfaces  which  could  be  made  easily 
available for the production of renewable energy (notably solar and in a number of 
locations,  wind  and  hydropower);  this  is  highlighted  in  the  recent  RePowerEU 

42 

 
 
 
 
package, in  which wastewater  facilities are identified as  good candidates  as “go-to-
areas”;26 

  As shown in the Evaluation, due to its public/semi-public nature, the sector is mainly 

if not only reacting to (EU) legal requirements;   

Fixing an EU energy neutrality sectoral  target  in the revised UWWTD ensures that the 
huge  potential  of  this  sector  in  terms  of  energy  efficiency  gains  and  self-production  is 
effectively captured, in particular considering that this sector is mainly reacting to (EU) 
legal  requirements.  It  will  help  MS  to  ensure  that  this  potential  is  effectively  captured 
even  if  this  sectoral  target,  like  targets  decided  for  other  specific  sectors  (including  for 
instance  car  industry  or  buildings),  will  partly  reduce  the  flexibility  left  to  the  MS  to 
choose  the  sectors  in  which  efforts  should  be  accomplished.  Nevertheless,  the 
cost/benefit analysis displayed in section 6.7 shows that reaching energy neutrality in this 
sector is particularly relevant. Also, in compliance with the principles of subsidiarity and 
proportionality, the proposed energy neutrality target would be applied at national level 
but not for each facility: flexibility would indeed be left to the MS on the choice of the 
facilities where investments will take place so that an optimisation of the efforts could be 
achieved. The large facilities can indeed be net producers of energy which is not always 
the case for smaller facilities.   

This specific target would complement and support the attainment of the objectives of the 
ongoing recast of the EED and revision of the RED (see below section 6.7 and 7.1).  As 
shown in Table 3 in section 5.1, without a specific target, part of the sector potential in 
terms of energy efficiency and of production of clean energy is expected to stay under-
exploited over the next decades: in the baseline scenario it was assumed that energy use 
from the sector would be reduced by 25,5% by 2040 which is far below the potential of 
the  sector.  By  encouraging  the  self-production  of  EU  based  biogas,  it  would  also 
contribute  to  reduce  energy  dependency,  one  of  the  objectives  of  the  recently  adopted 
‘REPowerEU’  Plan.  This  sectoral  target  would  also  help  moving  towards  the  EU 
objective of climate neutrality by 2050 and contribute to the implementation of the ‘Fit 
for  55’  and  the  ESR  (see  section  6.7  for  more  details).  In  that  sense,  there  is  no  direct 
overlap between the existing and forthcoming legislations and this sectoral target, but on 
the  contrary  the  energy  neutrality  target  will  complement  the  existing  or  planned 
legislation.  

In  practice,  energy  neutrality  can  be  met  through  a  specific  mix  of  actions  combining 
enhanced  energy  efficiency  (new  energy  efficient  pumps  and  aeration  process, 
optimization of the process, energy recovery from water falls in the plants), production of 
renewable  energy  on  site  (“go  to”  areas  for  solar/wind  energy  production),  and 
production of biogas from the digestion of residual sludge. The proposed target combined 
with  the  obligation  of  energy  audits  would  push  wastewater  operators  first  to  better 
assess their potential in terms of cost-effective energy savings and overall better energy 
management  and  then  to  develop  tailored  made  solutions.  As  shown  in  section  2.1.2.1 
and 2.1.2.2 each wastewater treatment facility is specific and therefore the optimal path 
to reach energy neutrality has to be defined for each wastewater treatment facility having 
regard to its specific process and opportunities.  

26 In the RePower EU Communication, “go-to areas” are limited and clearly defined land and sea areas 
available for renewable energy projects that do not have (as much as possible) environmental value. 

43 

 
 
                                                           
Denmark  intends  to  reach  energy  and  climate  neutrality  by  2030.  This  will  be 
accomplished through several actions agreed in an overall strategy:  
 

Investments  in  energy efficiency and sludge digestion  – since 2006, € 22,65 million 
are invested each year to reach energy neutrality by 2030.  
Introduction  of 
treatment  above  
for  N2O  emissions 
30.000 p.e. (covering 65% of the wastewater volume and 75% of N2O emissions from 
the process). The 30.000 threshold will be regularly reviewed.  

limit  values 

from 

 

  Monitoring,  reporting  and  benchmarking  of  all  wastewater  companies  on  their   

energy consumption and production, GHG emissions and targets.  

Under the Klimaatakkoord signed in 2010 (and confirmed by IBP in 2018 with the water 
competent authorities), the Netherlands intends to progressively reach energy neutrality 
already by 2025. To do this renewable energy sources (solar/wind) will be used but also 
measures  to  save  and  recover  energy.  8  treatment  plants  have  already  become  new 
producers of energy and another nine will follow soon. This is also the case in Bulgaria 
with  the  main  facility  of  Sofia.  Scotland  intends  to  reach  net  zero  emissions  by  2040. 
GHG  emissions  from  operations  were  already  cut  by  45%  by  using  more  efficient 
equipment, reducing leaks from pipes and using renewables.  

Box 1 – Actions agreed to meet Climate/Energy neutrality by the wastewater and waste sector 
in Denmark, the Netherlands, Sofia (Bulgaria) and Scotland – see Annex 10, report 19 

The impacts of following measures were therefore explored in section 6.7:   

 

Improve  the  sector’s  understanding  of  the  level  of  energy  use  through  new 
monitoring obligations and the requirement of regular energy audits (which are not 
required  under  the  revised  EED  –  see  section  2.1.1.2).  This  can  help  wastewater 
operators to better understand the potential savings they can achieve and to identify 
cost effective measures for each facility;     

  Progressively  moving  towards  an  EU  energy  neutrality  objective  (to  be  applied  at 
national  level)  for  the  sector  with  interim  targets  up  to  2040  to  ensure  regular 
progress  towards the final  objective of  energy  neutrality. The interim targets  would 
start by 2030 to leave enough time to all MS to make the required investments. They 
would  be  identical  for  all  MS  as  those  MS  having  a  less  advantageous  starting 
position  would  gain  more  benefits  than  the  others.  The  potential  financial  direct 
savings  are  indeed  more  important  in  MS  using  more  energy  today  for  their 
wastewater sector (see section 6.7 for more details).      

As mentioned in section 2.1, the avoidable part of GHG emissions of the sector amounts 
to 13.03 million tons of which around 46,45% is related to energy use.   

The OPC results as well as inputs received during the specific workshops showed that all 
stakeholder categories  broadly support the  generalisation of energy audits. There was a 
general recognition on the necessity to better understand and monitor energy use of the 
treatment plants so that measures can be taken to reduce energy use and where possible 
produce  energy.  On  average,  the  highest  rated  measure  was  related  to  introducing  an 
obligatory  energy  audit  in  larger  plants  (average  3.8),  academia  (4.2),  citizens  (4.0), 
NGOs (4.2), businesses (3.6) and public authorities (3.6). Citizens, NGOs and to a lesser 
extent academia were supportive on introducing energy related targets while mixed views 
were  expressed  by  public  authorities  and  business.  In  terms  of  stakeholder  response 

44 

 
 
 
 
 
 
patterns,  academics  (4.3)  indicated  the  most  support  for  the  measure  relating  to  setting 
energy  use  reduction  targets  based  on  UWWTP  sizes.  This  was,  on  the  other  hand, 
businesses  least  rated  option  (2.6),  with  a  generally  negative  perception.  Public 
authorities rated this measure 3.1, citizens 3.5 and NGOs 3.7. More recent contacts with 
the most important water industry representatives were clearly showing a willingness to 
improve energy efficiency for all wastewater treatment facilities above 10.000 p.e. and to 
reach  climate  neutrality  targets  for  all  facilities  above  100.000  p.e.  by  2035  et  for  all 
facilities above 10.000 p.e. by 2040. Some representatives from MS and business pointed 
out that these targets should be introduced for large UWWTPs only without specifying a 
specific size of the facilities. Targeting only facilities above 10.000 p.e. seems therefore 
reasonable and would partly answer to these comments. Most advanced MS were clearly 
supporting an EU wide target similar to their own target.  

5.2.8 Sludge management and water re-use 

Several actions considered in this IA will have an effect on sludge management. This is 
the case with the objective of climate and energy neutrality which will incentivise sludge 
digestion  and  production  of  biogas.  Beyond  this  effect,  the  proposed  actions  to  better 
monitor, track and reduce pollution at source (see section 5.2.6) will favour a safe use of 
treated water (water re-use) but also of sludge in line with the waste hierarchy.  

Particular attention should be given to the possible presence of micro-plastics/pollutants 
and  genes/bacteria  promoting  AMR  in  sludge,  when  used  in  agriculture.  This  aspect  is 
being specifically tackled in the ongoing Evaluation - and possible subsequent legislative 
revision - of the Sewage Sludge Directive and in the announced Healthy Soil Directive. 
Finally,  in  line  with  the  principle  of  circular  economy,  when  sludge  is  incinerated,  a 
minimum level of P recovery should be ensured.   

The concept of source control, i.e. targeting substances such as micro-plastics and micro-
pollutants at source, was widely supported by stakeholders in order to improve circularity 
in  the  wastewater  treatment  sector.  As  such,  if  sludge  and/or  water  is  to  be  reused, 
stakeholders  highlighted  that  there  is  a  need  for  tracking  and  preventing  pollution  at 
source.  

5.2.9 Wastewater and health  

Based on best practices in place in advanced MS notably for COVID-19 surveillance (see 
Annex  5)  and  on  the  March  2021  Recommendation  by  the  Commission,  the  following 
measures would be taken:   

  Ad-hoc  surveillance  of  COVID-19  and  its  variants  in  larger  wastewater  treatment 
plants (representing a significant share of the population); the surveillance should be 
adapted according to the local but also timely needs of the health authorities; 

  Regular monitoring of other pathogens with a view to define most effective actions to 

limit their dissemination;  

  Regular monitoring of AMR and when relevant, actions to limit AMR dissemination.  

A  structural  dialogue  between  health  and  wastewater  competent  authorities  should  also 
be  setup  with  the  aim  to  (1)  ensure  a  timely  transmission  of  the  information  to  the 
national health competent authorities; and (2) define the health relevant parameters to be 
temporarily or permanently followed in wastewaters. Enough flexibility should be left to 

45 

 
 
 
 
 
 
MS so that health competent authorities together with wastewater competent authorities 
can decide together the parameters to be monitored, the frequency and the location of the 
samples to be taken depending on the public health situation in each MS.   

Stakeholders  stated  that  if  wastewater  surveillance  were  to  take  place,  additional  costs 
associated  with  it should be  covered by  several  entities, for example health authorities. 
The preferred manner in which surveillance of wastewater should be incorporated in the 
Directive  is  through  the  means  of  guidelines  for  collaboration  between  UWWTPs  and 
health authorities, as well as establishing EU-wide binding standards on implementation. 

5.2.10 Transparency and Governance  

Different measures are available to ensure a better transparency of the sector but also to 
improve the understanding on the actual performances of the operators:  

 

In line with the best practices already in place in some MS, require from the operators 
to  monitor  some  key  performance  indicators  in  relation  to  their  economic,  social, 
environmental, energy and climate performances; these indicators would be included 
in the revised Directive on the basis of the OECD work (reference 6 in Annex 10);  
  Make this information accessible to the public either via online access or for the most 

essential information, on the invoices sent to the consumers.  

These  measures  are  aligned  to  similar  requirements  recently  adopted  under  the  revised 
Drinking Water Directive. They will also help to better implement the principles of the 
Aarhus  Convention  notably  on  access  to  information  and  public  participation.  While 
expressing  concerns  regarding  the  administrative  burden  for  authorities,  stakeholders 
consider that the current provisions on public information and transparency do not reflect 
current desirable levels of public engagement.  

5.2.11 Monitoring and reporting  

While improved and simplified monitoring and reporting are one of the objectives of the 
revision of the UWWTD, the actual measures depend on the selections made under the 
other options discussed in this impact assessment. As further explained in sections 6.11 
and  8,  additional  monitoring  activities  will  be  necessary  to  ensure  compliance  with  the 
new  proposed  requirements:  this  is  the  case  for  instance  for  micro-pollutants,  non-
domestic  pollution,  GHG  emissions  or  SWO/urban  runoffs.  The  existing  obligation 
would be also aligned to the current practices notably in terms of monitoring frequency: 
continuous  monitoring  of  key  parameters  needed  to  check  compliance  should  be 
envisaged for the larger facilities.  

 Reporting could be improved and where possible simplified by:  

  Removing the obligation for all MS to report every two years to the Commission and 
for the Commission to publish bi-yearly reports, by replacing it with the requirement 
for MS to host national standardised data sets which would be regularly updated (at 
least  annually)  and  to  provide  access  to  those  by  the  EEA/Commission.  This 
approach is similar to what was decided under the recently reviewed Drinking Water 
Directive  but  also  with  the  recent  efforts  of  the  EEA  and  the  Commission  to 
automatize  and  simplify  reporting.  During  the  consultation  it  was  mentioned  that 
some MS are already using databases directly filled by operators;  

46 

 
 
 
 
 
 
 
  Adapt  the  existing  reporting  obligation  to  include  actual  releases  on  top  to 
information  on  compliance  (pass/fail)  from  wastewater  treatment  plants.  To  limit 
administrative  burden,  this  new  requirement  would  apply  only  for  facilities  above 
10.000 p.e., representing 81% of the total EU load (see Figure 12);   
Include  in  the  reporting  obligations  information  on  energy  use,  measures  taken  to 
reduce SWO/urban runoff, and to improve access to sanitation;    

 

  Require MS to report if more than 2% of their load is collected/treated in IAS in their 
agglomerations, and to notify to the Commission summary information on the actions 
taken to respect the standards and ensure proper inspection of such IAS;  

  Ensure a full coherence between the UWWTD and the revised  Industrial Emissions 
Portal (former E-PRTR) Regulation to ensure best possible use of the same data, as 
well as full transparency;27 

  Exempt compliant MS from reporting under current Article 17. For the others, ensure 
synergies  and  coherence  between  Article  17  and  the  ‘water  enabling  condition’  for 
EU funding under Cohesion Policy 2021-2027. 

New  monitoring  obligations  were  clearly  supported  by  NGOs,  citizens  and  academics 
and to a certain extent by businesses and public authorities. NGOs noted that many of the 
substances  urgently  require  monitoring  (e.g.  micro-pollutants).  The  importance  of 
aligning  new  reporting  requirements  with  other  EU  policies  such  as  the  new  Industrial 
Emissions  Portal  (former  E-PRTR)  was  highlighted.  Generally,  the  pursuit  for  simpler 
and more harmonised reporting was supported by all stakeholder groups. 

5.2.12 Access to sanitation   

In  order  to  improve  access  to  sanitation,  and  in  full  synergy  with  existing  measures  to 
improve  access  to  water  under  the  revised  Drinking  Water  Directive,  the  following 
measures are considered in this IA:    
 

Identify vulnerable and marginalised people and require MS to take action to improve 
their access to sanitation  
In line with the subsidiarity principle, encourage MS to take appropriate measures to 
improve access to sanitation in large cities based on local conditions and constraints. 

 

The  extension  of  the  scope  of  the  Directive  to  smaller  agglomeration  is  expected  to 
improve access to sanitation in rural areas (see section 5.2.2). In the OPC, stakeholders 
indicated  that  access  to  sanitation  for  vulnerable  and  marginalised  groups  should  be 
required. Part of the respondents felt that flexibility should be left to MS on the way to 
improve access to sanitation.   

5.3 Options discarded at an early stage 

The  Evaluation  and  stakeholder  consultation  results  support  the  argument  that 
withdrawing  the  UWWTD  would  have  negative  consequences.  EU  citizens  would  no 
longer enjoy the same level of protection, as MS would no longer apply  the same high 
standards. Given the overall objective of protecting the environment and public health as 
well  as  the  reasoning  regarding  subsidiarity  provided  in  section  3,  this  option  was 

27  E-PRTR  includes  an  obligation  for  treatment  plants  above  100.000  p.e.  to  report  their  annual  mass 
releases and transfers. It also requires other large industrial facilities to report their releases into UWWTP.  

47 

 
 
 
 
                                                           
abandoned at the very beginning of the process.  There was also no stakeholder support 
for this option.  

Based on the stakeholder consultation, several options were considered at an early stage 
but rejected as either too vague or too prescriptive. Generally speaking, options based on 
guidance  documents  and  soft  approaches  were  not  further  considered  in  this  IA.  Their 
effects  would  be  too  limited  and  would  not  allow  reaching  the  objectives  described  in 
section  4.  As  explained  in  the  REFIT  Evaluation,  because  of  its  specific  market 
condition,  this  sector  mainly  adjusts  to  EU  legal  requirements.  The  clarity  and  relative 
simplicity  of the Directive  making it highly  enforceable  was recognised as one of its 
main success factors and this feature should be kept in the future. 

Some  flexibility  should  nevertheless  be  kept  in  order  to  ensure  an  optimal  use  of 
resources  -  including  EU  funding  -  to  reach  the  objectives.  In  that  sense,  the  option  of 
banning IAS was rejected at an early stage, because this technique, if well used, might 
still  be  justified,  depending  on  local  circumstances.  Similarly,  and  as  explained  in 
section  5.2.1,  imposing  detailed  EU  standards  constraining  the  design  of  solutions  for 
SWO and urban runoff was considered as not appropriate. 

Imposing individual energy efficiency targets for each collection and treatment system 
was  also  discarded  as  this  option  would  not  lead  to  optimising  investments  at  sector 
level.  Similarly, 
imposing  resource  efficiency  objectives  such  as  minimum 
percentages of sludge use in agriculture or mandatory anaerobic digestion was rejected 
as  well  as  the  option  of  introducing  minimum  rates  of  water  reuse.  This  is  also  in  line 
with the subsidiarity and proportionality principles, since the conditions are varying from 
one  MS  to  another  and  even  from  plant  to  plant.  To  better  apply  the  ‘polluters  pays’ 
principle, different types of pollutants and related products were considered (see Annex 
10,  report  2).  Possible  Extended  Producer  Responsibility  schemes  were  rejected  for  all 
other pollutants  than micro-pollutants. Contrary  to  micro-pollutants, there are indeed at 
this  stage  no  available  technologies  to  better  capture  these  pollutants  in  the  treatment 
plants.  

Imposing access to sanitation for all and everywhere seems unrealistic and too costly 
particularly  in  remote  areas.  The  current  scientific  knowledge  and  technological 
capabilities for wastewater treatment  do not  support the definition of science-evidence-
based  threshold  for  AMR  (ref  in  Annex  10,  report  11),  hence  such  an  option  was 
discarded too. 

48 

 
 
 
Drivers 

Problems 

Objectives 

Operational 
Objectives  

Contribution of the main options to the main specific 
objectives   

Climate 
change and 
urbanisation    

Increasing 
pollution 
from 
SWO/urban 
runoff 

Further reduce 
pollution from 
the ‘remaining 
sources’ 
(SWOs) 

SWO and urban runoff 
Reduction of the pollution sent to the environment from 
untreated water in case of heavy rains by:  
 

Integrated management plans based on improved 
monitoring 

Small 
agglomeratio
ns out of the 
Directive, 
unclear 
requirements 
and overuse 
of IAS  
Unclear 
criteria for 
‘sensitive 
areas’ and 
outdated 
standards for 
N & P 

Ageing 
population  
and  
Increasing 
use of 
pharmaceuti
cals and 
personal 
care 
products 

Inadequate 
monitoring, 
lack of 
incentives to 
‘do better’  

No tradition 
of producer 
responsibilit
y schemes 
for  water 
pollution  

Remaining 
pollution 
from small 
agglo and 
non-
compliant 
IAS 

High level of 
N & P 
releases 
leading to 
Eutrophicati
on 

Increasing 
releases of  
micro-
pollutants 

Lack of 
monitoring/u
nderstanding 
of some 
remaining 
sources and 
their impacts   
Insufficient 
application 
of the 
‘polluters 
pays 
principle‘ 

Further reduce 
pollution from 
the ‘remaining 
sources’ 
(smaller 
agglomerations 
and IAS) 

Further reduce 
nutrient (N and 
P),  pollution 
from urban 
sources 

To protect 
EU citizens 
and 
ecosystems 
from the 
remaining 
sources of 
insufficient
ly treated 
wastewater 

Further reduce 
micro-
pollutants 
pollution from 
urban sources 

  Actions to be decided at local level to prevent rain water 
in the network (green infrastructures), optimise existing 
infrastructures (storage, treatment plants) and when 
needed new infrastructures  

Small agglomerations and Individual Appropriate 
System 
Reduction of the pollution sent to the environment by:   
  Review of the thresholds above which the Directive 
applies (from 2.000 p.e. today to 500 or 1.000 p.e.) 
  Requiring MS to put in place systematic control of IAS 

combined with EU clear standards 

Nutrients 
Further reduction of N/P pollution sent to the environment 
by:  
  Establishing clear criteria where N/P treatment is 

required    
Stricter standards for N/P removal   

 

Micro-pollutants  
Reduction of micro-pollutants sent to the environment by:  
 

Establishing new standards for micro-pollutants emitted 
by wastewater treatment plants    
Establish an EPR scheme to incentive producers to put 
less toxic substances on the market  

 

For all options: improved monitoring and application of a 
‘risk based’ approach   
 

Integrated management plans for SWO/urban run-off to 
identify areas at risk and focus investments in areas at 
risk 
Investments only required for large facilities and for 
smaller facilities based on an identification of areas ‘at 
risk’ for micro-pollutants and N/P (eutrophication)  

Ensure that 
investments are 
taking place 
‘where it makes 
sense’   

 

Better apply the 
‘polluter pays’ 
principle  
Encourage 
investment and 
innovation in 
wastewater 
management. 

  Application of the Extended Producer Responsibility to 
cover new investments needs to treat micro-pollutants  
Innovation and investments encouraged by new 
standards for micro-pollutants, reinforced standards for 
N/P, improved management of SWO and urban run-off 

 

  Digitalisation/RTC needed for SWO/urban run-off 

management, N/P management and energy neutrality 
  New technologic development expected to reach energy 

neutrality while reinforcing water treatment  

Figure  14:  Links  between  drivers,  problems,  objectives,  specific  objectives  and  the  main 
options 

49 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
6.  WHAT ARE THE IMPACTS OF THE POLICY OPTIONS, HOW DO THEY COMPARE AND 

WHAT ARE THE PREFERRED OPTIONS?  

As  the  policy  options  are  quite  different  according  to  the  identified  problems,  their 
potential impacts, their comparison and the choice of the preferred options are discussed 
together  in  this  section.  The  assessment  of  impacts  focuses  primarily  on  the  economic 
(costs) and environmental impacts (emission of pollutants). The social impacts, beyond 
access  to  sanitation,  were  addressed  from  the  perspective  of  affordability  of  the 
wastewater services for the low-income households (see section 7).  

When alternative options were available, several criteria were used to identify ‘optimal’ 
(preferred)  options:  on  top  of  costs/benefits  and  costs/effectiveness,  the  contribution  to 
the  achievement  of  the  main  objectives,  the  enforceability  as  well  as  the  potential 
administrative burden were  considered. A summary of the selection  criteria applied for 
each option is provided in  Table 12, at the end of the present section whereas Figure 14  
above  displays  the  main  options,  their  contribution  to  solve  the  problems  and  their 
drivers while delivering on the specific objectives.   

The costs and benefits were assessed and presented with a 2040-time horizon: this is 
indeed the time needed for a realistic implementation of the measures considered in this 
IA and for a sound planning of the underlying, required investments. Beyond 2040, there 
would  be  too  many  uncertainties  on  the  expected  costs  and  benefits  of  the  envisaged 
measures.  As  detailed  in  section  4,  the  main  objective  of  this  initiative  as  well  as  the 
majority of its expected costs and impacts are related to water collection and treatment 
and  to  a  lesser  extent  energy  neutrality.  This  2040  horizon  takes  into  account  the  time 
required  for  the  water-related  investments.  It  also  takes  into  account  the  lessons  learnt 
from  the  application  of  the  1991  Directive  (over  ambitious  deadlines  leading  to  a 
multiplication of infringement cases – see the Evaluation for more details).  

The time needed to achieve energy neutrality was also taken into account: most advanced 
MS (see Box 1) are indeed expecting to reach energy neutrality by 2025/2030, meaning 
10 to 15 years before the proposed EU deadline which therefore would be realistic in the 
light of the potential gains and incentives related to better energy management but also 
the  available  technologies  to  move  towards  energy  neutrality.  The  recent  evolution  of 
energy  prices  is  providing  another  powerful  incentive  for  the  sector  to  accelerate  its 
efforts toward energy neutrality. It is also in line with the REPowerEU Communication 
objective to become less dependent for its energy production. For all these reasons, the 
2040 deadline appears to be both realistic and desirable. As detailed below (sections 6.7 
and  7.1),  reaching  energy  neutrality  by  2040  will  contribute  to  reduce  GHG  emission 
from the sector (around 33% of the ‘avoidable emissions) which is compatible with the 
objectives of the Fit for 55 initiative and the 2050 objective of carbon neutrality.  

For comparison purpose, a maximum feasible scenario was built showing what would 
be the effects of all technically feasible measures without taking into account their cost 
(see  Annex  4).  The  effects  on  emissions  in  waters  are  summarised  in  Figure  15  below 
and in Table 1 above.  

50 

 
Maximium Feasible Scenario (million pe/year) 

 300

 250

 200

 150

 100

 50

 -

BOD

N

P

E. Coli

Micro pollutants

Current

Baseline

Maximum feasible

Figure 15: Impacts of the current situation, baseline, and maximum feasible scenario on the 
remaining load  

As  detailed  in  Annex  4,  the  costs  were  estimated  based  on  reference  cost  functions 
(FEASIBLE functions). For the quantification of the benefits, the following shadow price 
were assumed: GHG emissions € 100 per t CO2e, and for 1 kg of BOD removed from the 
effluents  €  0.05,  €  20/kg  for  N  and  €  30/kg  for  P.  Additional  estimates  of  the  benefits 
based on willingness to pay were used in the case of SWOs and urban run-off (see Annex 
4). The cost and benefit methodologies were reviewed and improved by OECD (Annex 
10, report 4).  

6.1 Storm water overflows and urban runoff  

The expected pollution reduction as well as the costs and benefits of the different options 
are  summarised  in  Table  3  and  Table  4  below.  The  costs  and  impacts  of  the  additional 
investments needed will depend on the local conditions of each urban area. Nevertheless, 
the costs and effects of different measures were estimated using European hydrological 
and cost models (see Annex 4 for more details).  

Two types of costs were estimated: (1) costs of establishing the urban water management 
plans  including  monitoring  costs;  (2)  costs  of  actual  measures  included  in  the  plans  to 
limit untreated releases to 1% of the dry weather load (see section 5.2.1).  

The  average  cost  of  establishing  an  integrated  urban  water  management  plan  was 
estimated  at  €  0.09/year/p.e.  (source:  Annex  10,  report  1).28  These  plans  would  allow 
optimising existing and planned infrastructures leading to potentially significant savings 
in terms of new investments. Such integrated plans are already in place in some MS (see 
Annex 5), therefore it was estimated that around 80% of the concerned agglomerations 
would have to establish such plans. Annual monitoring costs are estimated at € 0.05 per 
p.e. (including RTC).   

28 The actual cost will depend on the complexity of the systems, the pre-existence of relevant information 
and the size of the considered area.   

51 

 
 
                                                           
The  costs  of  actual  measures  were  estimated  assuming  that  overflows  are  treated  in  a 
constructed  wetland  before  discharge.  The  effects  of  the  greening  of  urban  areas 
according to the objectives of the Biodiversity Strategy (Nature Restoration targets) were 
also  taken  into  account  in  the  modelling  (see  Annex  4).  Potential  savings  (on  average 
21,4%) due to real time control, digitalisation and better planning/management of waters 
in the cities (see Annex 10, reference 21) were applied to the costs estimates. 

Removal of 
Micro-pollutants 
(p.e./year) 
3.826.925 

   Options 

N removal t/year 

P removal 
t/year 

BOD  
t/year 

512 

3,476 

1 - Low ambition – 30% of  
agglo >100.000 p.e.  
2 - As above + 30% agglo > 
10.000 p.e.   
3 - High ambition - all 
agglo> 10.000 p.e. 
 Table 4: Annual pollution reduction by 2040 of actions to reduce urban runoff and SWOs – 
source JRC, ref in Annex 10, report 17 

6.558.744 

21.862.481 

98.276 

29.483 

19.795 

5,938 

2,919 

17.262 

876 

Options 1 and 2 include measures for all agglomerations respectively above 100.000 p.e. 
(Option 1) and 10.000 p.e. (Option 2) in areas ‘at risk’ where SWO releases represents a 
risk  for  the  environment.  For  the  calculations  of  the  impacts  of  these  Options,  it  was 
assumed that 30% of the agglomerations would require additional investments – which – 
according  to  available  data  from  the  WFD  and  the  BWD  appears  to  be  a  conservative 
approach (see section 2.1.1.2 and Annex 4 for more details).   

Options 

Costs    
€/year 

1 - Low ambition – 
30% of  agglo 
>100.000 p.e.  
2 - As above + 30% 
agglo > 10.000 p.e.   

3 - High ambition - 
all agglo> 10.000 p.e. 

218.979.413 

372.472.648 

Plans and 
monitoring  
€/year 

 43. 100.000    

Monetised 
benefits – 
water only 
€/year 
85.753.164 

10% of 
benefits – 
willingness to 
pay €/year 
365.537.530 

Total 
assumed  
benefits 
€/year 
 451.290.694 

57.600.000   

146.509.339 

 639.071.811 

785.581.149 

 1.241.575.494 

77.200.000  

488.364.462 

 2.130.239.369 

 2.618.603.831 

Table  5:  Annual  costs  and  benefits  by  2040  of  actions  to  reduce  urban  runoff  and  SWOs  – 
source JRC, ref in Annex 10, report 17 

Like  for  the  other  options,  a  partial  monetisation  of  the  benefits  was  achieved  on  the 
basis  of  the  avoided  N,  P  and  BOD  pollution.  In  absence  of  credible  shadow  price  for 
micro-pollutants  and  for  micro-plastics  (see  Annex  4),  the  benefits  related  to  water 
quality  are  nevertheless  under-estimated,  knowing  that  SWO  and  urban  run-off  are  a 
significant  source  of  these  pollutants.  Moreover,  the  monetisation  does  not  account  for 
the short duration, acute effects of pollution due to SWO/urban run-off, which may lead 
to  fish  die-off  and  temporary  impairment  of  the  aesthetics  and  safety  of  the  receiving 
waters.  

A  recently  published  study  (April  2022  –  see  Annex  10,  reference  22)  quantifies  the 
willingness to pay (WTP) for improved ecosystem services due to a better management 
of  SWO/urban  run-off  in  the  city  of  Berlin  (around  100  €/year/person).  Based  on  this, 
another estimate of the benefits was achieved for all options (more details in Annex 4).  

52 

 
 
 
   
 
 
In order to account for the fact that in many cases the perceived benefits can be smaller 
than in the Berlin case study, and to stay on a very conservative side in the estimation, it 
was assumed that the benefits would amount to 10% of the WPT as estimated in Berlin. 
Alternative  extrapolation  based  on  the  GDP  per  inhabitant  would  also  lead  to  an  over-
estimation of the benefits.29  

The results of both methods are displayed in Table 4  above. In the context of this IA and 
to compare the different options, the benefits  linked to  water quality were added to  the 
estimations of the willingness to pay.    

Preferred option:   

Requiring all agglomerations above 100.000 p.e. to produce an integrated plan and carry 
out  proper  monitoring  should  be  done  in  any  case:  it  would  concern  only  a  limited 
number  of  agglomerations  (914)  representing  a  significant  part  of  the  load.  As  for  the 
agglomerations between 10.000 and 100.000 p.e., regular monitoring should be in place 
to identify whether additional action would be needed.   

As shown in Table 12, the three options have similar benefits-costs ratios even if Options 
2 and 3 performs slightly  better than Option  1. More pollution would be captured with 
Option  3  but  not  always  in  areas  where  there  is  an  actual  risk  for  the  environment. 
Administrative burden would  be higher for Option 3 as more agglomerations would be 
covered. Option  1 has a slightly  lower benefit/cost  ratio than Option  2 and 3, while its 
administrative  burden  would  be  lower  than  for  Options  2  and  3.  The  contribution  of 
Option  1  to  the  main  objectives  of  this  initiative  would  be  lower  than  with  the  other 
Options.  

It is therefore proposed to consider Option 2 as the preferred Option. This Option offers 
the  best  combination  between  benefit/cost  ratio,  with  limited  administrative  burden 
(around 2.966 agglomerations would be concerned - mainly where there is a real risk for 
the  environment  compared  to  7.754  with  Option  3).  Option  3  entails  significant 
investments  in  all  agglomerations  above  10.000  p.e.  which  might  be  excessive 
particularly when the receiving water bodies are not ‘at risk’. With Option 2, investments 
would take place only in areas where there is a risk for the environment as identified by 
the  integrated  water  management  plans  leading  to  optimised  measures  to  be  decided  at 
local level. Criteria to define the areas at risk would be included in the revised Directive30 
as well as an indicative target for the water management plans (1% of dry weather loads 
–  see  section  5.2.1).  Applying  an  indicative  (not  legally  binding)  target  would  leave 
enough flexibility at local level on the decisions on actual actions to be taken depending 
on  their  local  cost/benefit  analysis  and  the  local  estimates  of  the  ‘willingness  to  pay’ 
which differs from one city to another.   

29 According to Eurostat, the average GDP per inhabitant in the EU amounts to 27.830 €/year compared to 
35.290 €/year in Germany. Based on the GDP/inhabitant, an extrapolation of the Berlin case would lead to 
WTP of 79 € per person which is considered by JRC experts as an over-estimation of the benefits. The 
same extrapolation in the MS having the lowest GDP/inhabitant (BG - 6.690 €) would lead to a WTP of 
18,9 € per person which is still about the double of the WTP used in the context of this IA (10 € per 
person). In that sense the assumption used in this IA appears to be prudent but reasonable.   
30 Criteria would be linked to risks to the environment notably when monitoring results shows high levels 
of  loads  (more  than  1%  of  dry  weather  loads)  leading  to  risk  of  not  achieving  the  objectives  of  other 
legislations such as the DWD, the BDW and the WFD.  

53 

 
                                                           
With the preferred option, around 9% of micro-plastics released in case of heavy rains 
would  be  further  captured  in  treatment  plants  and  as  well  as  potentially  significant 
additional  number  of  larger  pieces  of  plastic  (see  Annex  4  and  report  8  in  Annex  10). 
Finally, these measures are also aligned with the rationale underpinning the EU Climate 
Adaptation Strategy, the Biodiversity Strategy and the Zero Pollution Action Plan.  

6.2 Individual or other appropriate systems (IAS) 

The  proposed  measures  are  designed  to  ensure  the  full  implementation  of  the  existing 
Directive’s  requirements.  An  estimate  of  the  additional  administrative  costs  related  to 
performing regular inspections of IAS and complying with new reporting obligations was 
based  on  the  Austrian  advanced  experience:  the  annual  cost  of  ensuring  a  regular 
inspection is estimated at € 82.6 million per year for the EU 27 (see in Annex 10, report 
1).  The Austrian system is considered as one of the most advanced, meaning that with 
this level of costs a real performant inspection would be in place in all MS.   

As 26 MS have already  a legislation in place on IAS and some form of inspection, the 
total  additional  cost  of  improving  inspection  was  estimated  at  between  20  to  60%  of  € 
82,6  million.  Reporting  costs  would  amount  to  126.000  €/MS  per  year.  To  limit 
administrative burden, reporting obligation could be limited to MS reporting a high level 
of  IAS  in  their  agglomerations  of  above  2.000  p.e.:  it  would  concern  13  MS  reporting 
more  than  2%  (see  Figure  2).  Overall  reporting  costs  would  then  amount  to  1.64 
million/year. 

BOD 
reduction 
(Tons/year)  

N reduction 
(Tons/year)  

P reduction 
(Tons/year)  

Micro-
pollutants 
reduction 
(p.e./year)  

E. coli 
reduction 
(p.e./year)  

Administrative 
costs 
(million/year)  

Monetised 
Benefits 
(million/year) 

75.738  

23.2820 

32.480  

4.900.263  

4.190.288  

16,52 to 49,56   
+1.64 reporting 

566,9   

Table 6: Costs and benefits by 2040 of measures to ensure full implementation for IAS    

As  explained  in  section  5.1,  the  potential  pollutant  emission  reduction  was  included  in 
the  baseline.  Additional  emission  reductions  can  be  expected  if  EU  standards  are 
developed  for  IAS,  as  theses  would  apply  for  all  smaller  facilities  placed  on  the  EU 
territory.  As shown in Table 5, the monetised benefits are estimated at € 566,9 million 
which  is  exceeding  the  additional  costs  due  to  additional  efforts  on  inspection  and 
reporting.  

6.3 Small Agglomerations  

The impacts of reducing the existing threshold of 2.000 p.e. are summarised in Table 6.  

Options  

Number 
of 
Agglom
erations 

BOD 
reductio
n 
Tons/y 

N 
reductio
n 
Tons/y 

P 
reductio
n 
Tons/y 

Adminis
trative 
Million 
€/year 

Costs 
Million 
€/year 

Benefits 
Million 
€/year 

8.928 

19.138 

75.531 

Option 1 - 
1.000  p.e. 
Option 2 - 
500 p.e. 
Table 7: Cost and benefits by 2040 of expanding the scope of the Directive to agglomerations 
of 500 and 1.000 p.e. 

143.266 

16.822  

224,24 

30.354 

0,748  

0,472 

1.397 

2.642 

140,4 

284,3 

415,7 

4,9 

Micro-
pollutant
s 
(million 
p.e.)  
2,61 

54 

 
 
As  shown  in  Table  6,  for  all  options,  the  costs  are  lower  than  the  monetised  benefits. 
According to the MS answers to the questionnaire (see Annex 5), in 18 MS the majority 
of  the  small  agglomerations  are  already  connected  to  wastewater  treatment  plants  – 
which was taken into account in the baseline. Therefore, additional reporting work would 
be needed only for around 40% of the agglomerations or € 747.923 per year31 at EU level 
if the threshold is changed to 500 p.e. and € 471.560 for 1.000 p.e. (Annex 10, report 1). 

Preferred  option:  As  shown  in  Table  13,  the  benefit/cost  ratio  is  slightly  better  if  the 
thresholds  are  reduced  to  1.000  p.e.  (1,6  compared  to  1,46)  while  administrative  costs 
would  be  reduced  by  half.    It  is  therefore  proposed  to  consider  this  Option  1  as  the 
preferred  Option  even  if  Option  2  would  have  delivered  slightly  higher  pollution 
reduction.  In  terms  of  enforceability,  the  preferred  option  scores  better  as  even  if  the 
thresholds  are  very  clear  for  both  options,  targeting  less  agglomerations  will  ease 
compliance checking and limit administrative burden.      

6.4 N and P releases and eutrophication  

The impacts of several combinations of measures based on removal efficiency applied to 
different  sizes  of  facilities  were modelled  (see  Annex 4 and Annex 10, report 15). The 
impacts of the main following options are summarised in Table 7 below. 

Preferred option:  As shown in Table 12 and in Table 7, the benefit/cost ratio is positive 
for all options. Options 2 and 4 are nevertheless scoring better than the others. Option 4 
will bring more N/P but also GHG reduction. In that sense, the coherence with the Green 
Deal as well as the effectiveness in terms of reduced water pollution is higher. Compared 
to  other  less  ambitious  Options,  Option  4  will  bring  limited  additional  administrative 
burden  as  facilities  above  10.000  p.e.  are  already  subject  to  reporting  while  better 
contributing to the objectives.  

It is  therefore proposed  to  consider Option  4 as  the preferred option. With this  Option, 
the  obligation  to  install  additional  tertiary  treatment  to  remove  N/P  will  be  limited  to 
areas subject to eutrophication or at risk of eutrophication as it is the case today but with 
more clarity and coherence with the WFD, the MSFD and the Nitrates Directive on the 
criteria  to  designate  sensitive  areas.  Some  areas  incontestably  subject  to  eutrophication 
consistently  with  the  data  generated  by  the  MSFD,  the  WFD  but  also  the  Nitrates 
Directive could be included in the annex of the Directive.32  

31 0.5 day/operator based on cost of a FTE of 123,2 €/day – source: Eurostat – see Annex 10, report 1  
32 Parts of the North Sea, Black Sea, North of the Adriatic Sea, Baltic Sea     

55 

 
 
 
                                                           
Options  

N 
reduction 
(t/year) 

P 
reduction 
(t/year) 

GHG 
reduction 
(t/year) 

Costs (€ 
million) 

Benefits  
N/P 
removal in 
water (€ 
million)  

Benefits 
GHG 
reduction 
(€ million) 

 1. Low ambition - N/P 
removal - all facilities 
above 100.000 p.e.  

2. Medium – as above + 
N efficiency to 85% and 
P to 90% 

3. N/P removal for all 
facilities > 10.000 p.e. 

4. N/P removal - all 
facilities  > 100.000 p.e. 
+ facilities between 10 
and 100.000 in sensitive 
areas + N/P increased 
efficiency33  

5. High ambition - As 
above + N efficiency to 
85% and P to 90% 

54.817 

9.359 

692.842 

801  

1.377 

69,842 

168. 228 

16.964 

922.063 

1.420 

3.873 

92,206 

84.603 

15.288 

1.228.372 

1.395 

2.151 

122,84 

215.133 

28.130 

1.391.487 

2.008,5 

5.147 

139,149 

282.524 

29.054 

1.662.634 

2.598 

6.523 

166,263 

 Table 8: Summary of the main impacts by 2040 of measures to reduce N/P  

6.5 Micro-pollutants   

Table 8 below summarises the model results for a selection of different options as regards 
the treatment of micro-pollutants (see Annex 4 for details).   

Options 

1. Low ambition - all plants > 
100 k p.e.  
2. All plants >100 k p.e. + 
plants 10 k to 100 k in areas 
at ’risk’ 34 
3. High ambition - all plants > 
10k p.e.  

Costs  
(Million 
€/year) 
841 

Toxic load 
avoided   
(p.e.) 
59.236  

Avoided toxic 
load  in areas 
at risk (p.e.) 
32.875  

Additional 
GHG (Million t 
CO2e/year)      
0 to 4,33 

1.185,51 

68,198 

 41.836 

0 to 4,97 

2.651,82 

103,431 

 41.836 

0 to 7,58 

Table 9: Impacts by 2040 of measures to reduce micro-pollutants, source JRC - Annex 4 and ref 
in Annex 10, report 13 and 14 

As  explained  in  the  glossary,  the  lower  the  dilution  rate,  the  higher  the  risks  for  the 
environment. Additional energy would be needed to treat micro-pollutants. In Table 8 an 
estimate of the related GHG emissions is provided. These additional emissions could be 
neutralised when energy neutrality will be met in the sector.   

33 For Option 4, it was estimated that around 50% of the facilities between 10.000 and 100.000 p.e. not yet 
equipped with N/P removal equipment are in sensitive areas and should be equipped by 2040 
34 In this IA, it was assumed that 70% of facilities between 10.000 and 100.000 p.e. with a dilution rate of 
10 or less would be considered as ‘at risk’- see Annex 4. 

56 

 
 
 
  
                                                           
Preferred option:      

As shown in Table 8 and Table 12, there is a direct correlation between the reduction of 
the  toxic  load  and  the  costs.  Compared  to  Option  1,  Option  2  delivers  better  results  in 
terms of avoided load in areas ‘at risk’, where the dilution rate is below 10. Compared to 
Option 3, Option 2 is more cost effective as it will allow prioritising the efforts where the 
risk for the environment is higher.35  

The administrative burden of Options 2 and 3 is  slightly higher than Option  1  – which 
nevertheless  delivers  less  reduction  of  the  toxic  load  (both  in  and  outside  the  areas  ‘at 
risk).  All  Options  are  similar  in  terms  of  enforceability  even  if  Option  2  will  require 
slightly  additional  efforts  to  check  that  MS  did  properly  identify  the  areas  at  risk. 
Requiring an unconditional advanced treatment for facilities between 10.000 and 100.000 
p.e. as in Option 3 would lead to disproportionally high cost when compared to expected 
reduction  of  polluting  emissions.  Balancing  all  the  criteria,  it  is  proposed  to  consider 
Option 2 as the preferred Option. With the preferred option, the toxicity of the released 
waters would be reduced by 44% against the current situation, of which more than 60% 
would happen in areas ‘at risk’. 

To  give  enough  time  to  plan  the  required  investments,  advanced  equipment  would  be 
installed  within  a  sufficient  time  period  by  2035  (more  than  10  years)  for  all  facilities 
above 100.000 p.e. and 5 additional years would be given for the others. These deadlines 
are realistic based notably on the experience from Switzerland.36  

Monitoring costs for the preferred option are estimated around €11 million/ year based on 
monthly samples (Annex 10, report 1). Reporting costs are considered as negligible as all 
facilities above 10.000 p.e. are already subject to reporting obligations.    

Producer responsibility, application of the ‘polluters pays’ principle:  

The  feasibility  and  impacts  of  covering  the  additional  cost  for  advanced  treatment 
through  a  system  of  producer  responsibility  was  assessed  (report  2  in  Annex  10). 
According  to  the  best  available  data  today,  and  recognising  uncertainties  on  the  data 
gathered37,  substances  used  in  pharmaceuticals  and  personal  care  products  (PCPs) 
represent  the  majority  of  micro-pollutants  inputs  and  toxicity  in  wastewater  treatment 
plants  justifying  additional  investments  in  advanced  treatment  for micro-pollutants  (see 
Annex  10  reports  2,  15  and  16).  Pharmaceuticals  represent  59%  of  input  quantities  to 
wastewater  treatment  plants  (14%  for  PCPs),  48%  of  the  toxic  chronic  load  (17%  for 
PCPs) and 66% of the total toxic load PNEC- see Glossary (26% for PCPs).  

In compliance with the “polluter pays” principle included in Article 191 of TFEU, these 
sectors  should  be  financially  responsible  for  the  additional  costs  related  to  additional 
treatment needed to treat the pollution they generate (€ 1.186 million/year for all micro-
pollutants).  In  practice,  and  similarly  to  the  EPR  schemes  in  place  for  several  waste 

35  On  the  basis  of  the  outcomes  of  a  risk  assessment  based  on  simple  criteria  such  as  low  dilution  rate,  
presence of bathing areas and/or where raw water is extracted for the production of drinking water. 
36 In Switzerland 100 ‘priority’ facilities will be equipped with advanced treatment by 2040. 
37  There  are  uncertainties  on  the  concentration  of  substances  found  in  the  treatment  plants  and  on  the 
toxicity of the substances – see also  Table  1. As it  was the case at the beginning of  most EPR schemes, 
these uncertainties are expected to be rapidly limited with the introduction of the declaration on products 
placed on the EU market by the producers/importers. 

57 

 
                                                           
streams, those placing PCPs/pharmaceuticals on the EU market would have to pay fees to 
a central organisation (PRO) based on the quantities and toxicity of their products. The 
funds would then be used mainly to finance the additionally required treatment through 
contracts with wastewater operators but also to cover the additional administrative costs. 
Such  system  will  be  in  line  with  the  concept  of  Extended  Producer  Responsibility  as 
defined under Article 8 of the Waste Framework Directive. More details on the practical 
organisation,  the  responsibilities  and  roles  of  the  different  involved  actors  and  their 
interactions  is  provided  in  Annex  9.  On  top  of  deciding  on  whether  a  producer 
responsibility system should be applied or not, the main choice to be done at this stage 
and in the EU legislation are related to the scope of the EPR scheme, the cost coverage of 
the  scheme,  the  principles  on  how  the  fees  to  be  paid  will  be  applied  and  the  level  of 
transparency of the system. In this impact assessment it was assumed that: 

  The  scope  of  the  EPR  schemes  would  cover  pharmaceuticals  and  PCPs.  A 
review  clause  could  be  included  in  case  new  knowledge  and  understanding 
become  available  on  the  products  placed  on  the  market  generating  micro-
pollutants and treated with the new advanced treatments.31  

  The same principles in terms of fee modulation/transparency as defined in Article 
8 of the Waste Framework Directive would be applied. In other terms, the fees to 
be  paid  by  those  placing  PCPs  and  pharmaceuticals  on  the  market  would  be 
linked to the quantities of the products they placed on the market and the potential 
toxicity  of  the  related  residues.  This  modulation  of  the  fees  paid  by  the 
producers/importers  would  be  established  so  that  substitution  to  most  toxic 
substances could be incentivised. 

  Similar  requirements  to  those  included  in  the  Waste  Framework  Directive  in 
terms  of  transparency  would  be  requested  from  the  producers/importers  and  for 
their PRO. These costs (administrative costs related to the EPR scheme but also 
to regular external independent audits were assesses in this IA – see below).    

The  additional  costs  related  to  an  EPR  scheme  is  due  to  administrative  costs.  These 
costs were estimated at € 16.6 million per year (less than 1.4%) mainly for the Producer 
Responsibility Organisation - PRO (€ 11.2 million) and to a lesser extent for the sectors 
(€ 5 million – declaration of what is set on the EU market). Costs for MS (control of the 
system – 0.06 million) and for wastewater operators (contracts with PRO – 0.34 million) 
are more modest. Depending on the decisions taken by each company in the two sectors, 
the  additional  costs  due  to  the  fees  paid  to  the  PRO  would  be  covered  either  by  an 
increase of products price (estimated at maximum 0,6%, of the annual expenses for PCPs 
and Pharmaceuticals) or by a reduction of the profit margins (estimated at maximum 0,6 
to 0,9%) – see report 2 in Annex 10.   

There are several advantages of an EPR scheme including: 

  A  better  application  of  the  polluter  pays  principle  (in 

the 
recommendation  of  a  recent  Court  of  Auditor  report),  entailing  an  incentive  for 
industrial producers to develop less toxic products;  

line  with 

  Reduced pressure on public budgets and water tariffs while ensuring a stable and 
reliable financing of the required investments needed to treat micro-pollutants;  

58 

 
  Expected  gains  in  governance  through  new  dialogue  and  contractual  relations 

between wastewater operators and relevant industrial producers.   

The  alternative  to  an  EPR  scheme  would  consist  in  a  ‘classical’  financing  of  the 
required investments: 1.186 € bn/year by 2040 would have to be covered by water tariffs 
(€ 0.83 bn/year38) and public budgets  (€ 0,37 bn/year). These increases  of water tariffs 
and  public  budget  contribution  would  come  on  top  of  the  expected  increase  due  to  the 
other measures identified in the preferred option (see section 7.1). Most of the advantages 
identified above linked with an EPR scheme would then be lost (incentives for less toxic 
products,  gains  in  governance)  while  an  occasion  to  better  apply  the  ‘polluters  pays’ 
principle  would  be  missed  despite  the  obligations  included  in  the  Treaty  and  the 
recommendation of the Court of Auditors (see section 2.1.3.2.).    

6.6 Non-domestic discharges 

The average cost of taking samples and make analysis of a large spectrum of substances 
in the inlets and outlets of the wastewater facilities is estimated at € 5.000 per sample (ref 
in Annex 10, report 1). At least two samples would be taken each year for the facilities 
above 100.000 p.e. and one every two years for the facilities between 10.000 and 100.000 
p.e. – this would give an overview of the type of pollution coming in and going out the 
facilities,  while  keeping  the  number  of  samples  proportional  to  the  purpose  of  the 
exercise.  This  information  can  be  used  then  to  better  ‘track’  non  desirable  pollution 
entering the plants and take further measures to  limit at  source this pollution. The total 
costs at EU level would amount to € 25,695 million per year.   

The additional costs of ensuring more transparency and when required consultation of the 
wastewater operators on the permits given to facilities connected to the public network is 
difficult to assess in absence of data on the number of permits. The impact assessment for 
amending  the  IED  concludes  that  a  better  alignment  between  the  IED  and  UWWTD 
would  result  in  reduced  releases  of  polluting  substance  to  water  and  may  require  a 
limited number of IED operators to invest into treatment equipment on site. 

The benefits of this measure are multiple (but not quantifiable): (1) reducing pollution at 
source  will  improve  the  quality  of  the  sludge  but  also  of  the  treated  water  making  it 
available for reuse notably in agriculture; (2) the functioning of the wastewater treatment 
could  also  be  improved;  (3)  less  pollutants  will  be  released  into  the  environment  and 
more  coherence  will  be  ensured  with  the  EQSD.  This  would  help  to  achieve  the 
objectives of preventing pollution at source and improving the ‘circularity’ of the whole 
sector. In order to improve the knowledge on micro-plastics releases, regular monitoring 
should  be  progressively  put  in  place  based  on  harmonised  sampling  and  analytical 
methods. 

6.7 Energy neutrality and GHG emissions  

The  estimated  costs  and  benefits  to  move  towards  energy  neutrality  are  summarised  in 
Table  9:  below.  The  average  cost  of  establishing  energy  audit  every  5  years  was 
estimated at 4.000 € per audit (ref in Annex 10, report 1). In a first period (by 2030), the 
audits  would  be  imposed  only  on  the  larger  facilities  above  100.000  p.e.  (total  costs  at 

38 Assuming that ‘historical’ ways of funding water infrastructures would continue: 70% would be covered 
by water tariffs, the 30% remaining by public budgets – see Figure 10 

59 

 
                                                           
EU level of € 0.74 million per year). Average monitoring yearly costs are estimated at € 
12  million  at  EU  level  (between  8.3  and  15,8  million  per  year).39  To  meet  the  2040 
energy  neutrality  target,  audits  and  monitoring  would  also  be  needed  by  2035  for  all 
facilities  above  10.000  p.e.:  81.4%  of  the  total  load  (and  energy  use)  would  then  be 
covered  with  7.527  facilities.  The  total  annual  cost  by  2035  for  all  audits  would  then 
amount to € 6 million per year and the monitoring costs would reach an average of € 98,7 
million  (between  €  67,5  and  130  million  per  year).  Imposing  audits  and  systemic 
monitoring  on  facilities  below  10.000  p.e.  would  be  disproportionate  (large  number  of 
facilities for a limited treated load and related energy use – see Figure 12).      

Costs 
(million 
€/year)     

Expected 
savings 
(million 
€/year) 

GHG 
emission 
reduction 
(tons 
CO2e/year) 

% of 
avoidable 
GHG 
emissions  

Monetised 
benefits 
(million 
€/year)    

Baseline  

410 

510 

1.188.477 

11,85% 

118,9 

Energy neutrality  

  1.560   

2.000 

4.660.695 

45,46% 

466,07 

Energy neutrality target 
compared to baseline  

1.150 

1.490 

3.472.218 

33.61% 

347,22 

Table  10:  Costs  and  benefits  by  2040  associated  to energy  neutrality  in  comparison  with the 
baseline - € million by 2040  

In  this  IA,  an  estimate  of  the  costs  needed  to  move  towards  energy  neutrality  was 
calculated based on the solid experience of Denmark (annual cost of 22,65 million € per 
year  to  cover  investments  with  between  10  and  40  years  of  amortization  time).  An 
extrapolation  of  the  DK  figures  at  EU  level  would  lead  to  an  annual  cost  of  €  1,561 
billion (EU capacity of 517 million p.e. compared to 7,5 million p.e. in DK). The main 
investments in Denmark were devoted to biogas production from sludge (around 85% of 
the  investments)  complemented  by  intelligent  control  and  management,  renew  of  heat 
pumps  and  aeration.  No  investments  in  other  renewables  like  solar  or  wind  production 
were  included  in  the  calculation.  Reaching  energy  neutrality  would  represent  a  direct 
financial saving of 2 billion € per year for the whole sector – which is the actual costs of 
the  energy  used  in  wastewater  treatment  facilities.  (ref  in  Annex  10,  report  1).  The 
potential net saving linked with an energy neutrality target would therefore amount 
to € 0,439 billion per year for the sector.  

The  data  on  the  costs  to  reach  energy  neutrality  provided  by  Denmark  are  based  on  a 
successful  and  concrete  experience.  Their  extrapolation  to  the  whole  EU  is  most 
probably leading to an over estimation of the costs as digestion of the sludge would not 
always  represent  the  most  cost-effective  solution  to  produce  renewable  energy:  the 
potential for wind or mainly solar production could be more significant in other MS. At 
the  same  time,  the  potential  savings  (2  billion  €  per  year)  were  calculated  before  the 
recent events in Ukraine having led to a significant increase in energy prices.   

In  the  context  of  this  IA,  and  in  the  light  of  the  uncertainties  mainly  related  to  the 
evolution of the energy markets, a very prudent and conservative approach was taken: 

39 Annual operational and investment costs are estimated between € 12 and 21.000 per facility. It is  was 
estimated that 75% of the facilities have already monitoring in place - see Annex 5.1 

60 

 
 
                                                           
it was assumed that the costs of additional investments and related administrative costs to 
reach energy neutrality would be compensated by the financial savings due to increased 
energy efficiency and the production of renewables. By doing so, it can be assumed that 
potential  savings  are  under-estimated  with  energy  prices  expected  to  increase  in  the 
short/mid- term. These potential savings will contribute to limit the potential increases of 
water tariffs and public budget intervention (see section 7.1). 

Similarly, extrapolating the DK experience shows that the equivalent of  around 16.000 
GW/h of biogas (similar to the consumption of SE for instance) could be produced in the 
EU thanks trough sludge digestion. This biogas can be used as natural gas and substitute 
EU imports of gas which is one of the objectives of the REPower EU Plan.  

Other advantages of such a target are summarised in Table 10 below. The contribution of 
this target to the objectives of this IA (objective 3) but also to the implementation of key 
EU  policies  related  to  climate  change,  energy  including  EU  independence  are 
compensating the additional administrative burden mainly due to increased energy audits 
in the sector.  

Contribution to 
Objective 3 
(EGD) 

Contribution to 
RePower 
EU/energy 
independence  

Contribution to 
ESR, REDII and 
EED targets  

Administra
tive burden  

No action (baseline scenario)  
Energy neutrality target  

+ 
+ 
++++ 
++++ 
Table 11:  Comparison of the pros and cons of an energy neutrality target  

+ 
++++ 

0 
-- 

The added value of the energy neutrality target is clearly demonstrated in  Table 10 and 
Table 11. Compared to the baseline, reaching energy neutrality by 2040 would lead to a 
reduction of GHG of 3.472.218 tons  of CO2eq  –  representing a monetised benefit of € 
347,22  million  which  compared  to  the  baseline  without  an  energy  neutrality  target 
represents a clear improvement. The costs to reach energy neutrality would be more than 
compensated by the expected financial savings due to energy savings and production of 
renewables.  And  the  production  of  renewables  in  particular  biogas  would  contribute  to 
the independence of the EU in terms of energy production.  

6.8 Governance – transparency  

According to the OECD (see Annex 10, reports 5 and 6), additional costs can be expected 
at  the  beginning  for  operators  not  having  in  place  a  systematic  monitoring  of  their  key 
performance  indicators.  On  the  longer  run,  regularly  monitoring  of  key  performance 
indicators will provide  a better understanding on potential operating improvements and 
savings.  Making  these  key  indicators  publically  available  by  digital  means  and  on  the 
water bills is expected to increase public willingness to pay but also collective awareness. 
A  better  empowerment  of  citizen  might  also  lead  to  additional  pressure  on  wastewater 
operators  to  improve  their  performances.  The  potential  concrete  effects  are  difficult  to 
quantify, but as shown in Figure 9, the margins of progress might be significant.  

In the absence of better estimates, it was assumed that the additional costs linked with the 
regular  performance  monitoring  and  with  ensuring  transparency  would  be  more  than 
compensated by the expected savings for wastewater operators. These new requirements 
will be fully aligned with the new requirements of the recently adopted Drinking Water 

61 

 
  
Directive  in  terms  of  transparency  and  follow-up  of  key  indicators.  This  coherence  is 
needed as water bills cover, in most MS, both water supply and sanitation.  

The  implementation  of  a  possible  EPR  scheme  for  micro-pollutants  will  have  a  direct 
effect on governance: wastewater operators will be requested to negotiate and implement 
service contracts with PRO with clear objectives and performance requirements.  

6.9 Wastewater and health  

Ensuring  a  permanent  dialogue  between  public  health  authorities  and  competent 
authorities  for  wastewater  will  bring  multiple  benefits  in  terms  of  public  health.  New 
pathogens could detected at early stage as well as the spread of different diseases but also 
other public health relevant parameters.    

The  potential  costs  for  the  establishment  of  a  wastewater  surveillance  of  SARS-CoV-2 
virus was calculated on a basis of regular sampling and analyse (twice a week) for around 
70% of the population. For the EU 27, the total cost would amount to 20 million € per 
year (JRC 2020  – estimate made in  the context  of the  Recommendation  to  the MS).  In 
2021,  the  Commission  has  provided  a  financial  support  of  €  20  million  to  MS  having 
applied  for  a  support  (26  MS)  to  accelerate  or  intensify  wastewater  monitoring.  In  all 
cases, these costs would be by far exceed by the benefits for the society linked with an 
improved prevention and management of the pandemic.   

The  same  reasoning  would  apply  for  other  health  related  parameters  including  AMR 
surveillance. For the later, the cost of bi-annual sampling and analyse of AMR in larger 
water  treatment  facilities  above  100.000  p.e.  representing  around  46%  of  the  EU 
population would amount to € 9,74 million  per year (€ 5.000 par sample/analyse).     

6.10 Access to sanitation   

Similarly  to  the  requirements  of  the  revised  Drinking  Water  Directive,  MS  would  be 
required  to  first  identify  marginalised  and  vulnerable  people  not  having  access  to 
sanitation and then take measures to ensure/improve access to sanitation. MS would also 
be  encouraged  to  ensure/improve  access  to  public  toilets  in  cities  for  all.  The 
identification  of  the  marginalised  and  vulnerable  people  lacking  access  to  sanitation 
would  be  very  similar  to  the  requirements  already  in  place  under  the  revised  Drinking 
Water Directive. Therefore, no additional major costs are expected.  

The costs of the actual measures to improve access to sanitation would have to be defined 
at  local  level  depending  on  local  conditions.  No  EU  target  would  be  fixed,  but  just  an 
obligation to take measures based on a proper identification of the concerned people. MS 
would also be ‘encouraged’ to improve access to public toilets in their cities including for 
vulnerable and marginalised people, but again without any specific EU target.   

In order to enforce the new requirements on access to sanitation, MS would be required 
to regularly report (every 5 years as in the DWD for access to water) on the actions taken 
to  improve  access  to  sanitation.    No  estimate  of  actual  benefits  could  be  calculated, 
however it is likely that the benefits in terms of both public health and welfare would be 
higher than the costs.  

62 

 
6.11 Reporting  

Compared to the baseline, and taking into account all preferred options, the yearly costs 
and savings related to reporting obligation are summarised in Table 11 and detailed in the 
report in Annex 10, report 1.  

Whilst the overall process of data gathering will be simplified, the revised UWWTD will 
require that MS  collect  more data. This  would allow assessing compliance  for the new 
requirements regarding SWOs and urban runoff, energy, GHG emissions.  

At EU Commission and EEA levels, no major changes are expected: the savings linked 
with the abandonment of the two years reporting would be compensated by the efforts to 
regularly verify the national databases and the additional efforts to ensure compliance for 
the smaller facilities (between 1.000 and 2.000 p.e.). 

    Commission 
and EEA  

Member 
States 

Operators   

Municipalities  

EPR  

Costs of € 10 
million – once  

Minor 
savings 
expected 
from 
reduced 
reports 
under 
Article 17   

E-PRTR/UWWTD:  limited 
savings 

Reporting small agglo: € M 
0,471 

GHG/Micro-pollutants 
monitoring: € 109,7 million    

 Table 12: Reporting costs and potential savings by 2040  

SWO/Urban 
runoff: € 57,7 
million 

Cost for PRO of € 
11,2 million and 
for the concerned 
sectors € 5 million  

Adapting the existing reporting system using a common format would nevertheless imply 
a one-off IT cost – estimated at € 10 million for the EU. The EEA is already working on 
improving its reporting system following this approach. This is also the line taken in the 
revised  Drinking  Water  Directive  –  which  will  increase  the  synergies  and  coherence 
between the reporting obligations, ultimately providing more accurate data for the overall 
Environmental  Monitoring  Framework  as  set  up  under  the  8th  Environmental  Action 
Programme,  and  more  specifically  feeding  the  bi-yearly  Zero  Pollution  Monitoring 
Report.   

At  MS  level,  the  potential  savings  due  to  the  simplification  of  the  system  (national 
databases directly accessible to operators combined with the abandonment of the 2 year 
reporting obligations) would  be compensated by the additional reporting obligations on 
micro-pollutants, energy neutrality. 13 MS having less than 5% distance to target would 
not  be  obliged  to  report  under  Article  17  –  representing  another  limited  saving  of  € 
32.032 per year; additional savings can be expected by better aligning Article 17 to the 
enabling condition under the Multiannual Financial Framework 2021 – 2027. 

At Municipal level, additional costs will arise from the obligation to establish integrated 
plans on SWO/urban runoff (€37,03 million) plus costs of monitoring (€ 20,57 million). 
Part of these costs could be shared with operators. As explained in section 6.1, adequate 
planning and monitoring could save major investments. 

level,  additional  administrative  costs  are  expected 

At  Operators 
for  small 
agglomerations not currently covered by the Directive (€ 0,471 million). Reporting work 
for operators above 2.000 p.e. will broadly remain similar to the current work – gains in 
terms  of  digitalisation  would  compensate  the  additional  efforts  required  to  report  more 
data  notably  on  GHG,  energy,  micro-pollutants  and  other  parameters.  Enhanced 

63 

 
coherence between reporting obligations under the E-PRTR and the UWWTD may result 
in limited savings in administrative burden. Monitoring costs are expected to increase for 
operators: € 11 million will be necessary to monitor micro-pollutants, € 98,7 million for 
energy and GHG. Assuming that (1) the monitoring costs for micro-pollutants would be 
covered  by  the  EPR  scheme;  (2)  40%  of  the  operators  are  either  mixed  or  private 
companies  (the  others  being  100%  public),  the  addition  administrative  costs  for  the 
mixed/private  sector  would  amount  to  €  39,29  million  per  year.  These  additional  costs 
will be in any case passed on the competent public authorities having contracts with these 
operators and be  compensated by the gains expected from the application of the energy 
neutrality target (see section 6.7). 

Additional  administrative  costs  of  €  16.6  million  per  year  are  associated  with  the  new 
EPR scheme (see section 6.5) mainly for the PRO (€ 11.2 million) and to a lesser extent 
for the sectors (€ 5 million – declaration of what is set on the EU market). 

64 

 
 
Costs € 
million/year 

Benefits € 
million/year 

 Benefits/Costs   

Effectiveness - 
water pollution   

Coherence 
with the Green 
Deal   

Enforceability  

Admin. burden 
- number of 
facilties/agglo  

Admin. burden 
- Costs € 
million/year 

Strom Water Overflow/Urban run off 

1. All agglomerations at risk > 100.000 p.e.  
2. All agglomerations at risk > 10.000p.e. 
3. All agglomerations > 10.000 p.e. 

Small Scale Agglomerations  

1. All agglomerations > 1.000 pe  
2. All agglomerations above 500 pe  

Nitrogen and Phosphorus Removal  

1. Low ambition - N/P removal only for all 
facilities above 100.000 pe  
2. Medium – as above + N efficiency to 85% and 
P to 90% 
3. N/P removal for all facilities > 10.000 pe 
 4. N/P removal for all facilities above 100.000 
pe + facilities between 10 and 100.000 in 
sensitive areas + N/P increased efficiency  
5. High ambition - All facilities  10 kp.e. + N 
efficiency to 85% and P efficiency to 90% 

219 
372,5 
1.241 

140 
284 

801 

1.420 
1.395 

2.009 

2.598 

Micro Pollutants   

1. Low ambition - all plants > 100 k pe  

841 

2. All plants >100 k pe, + plants 'a risks' 
between 10 k and 100 k 

3. High ambition - all plants > 10k pe with 
dilution < 100 

1.186 

2.652 

451,3 
785,6 
2.618,6 

224 
416 

1.447 

3.965 
2.274 

5.286 

6.689 
(Total Toxic 
load avoided 
p.e.) 
59.236 

68.198 

103.431 

2,06 
2,11 
2,11 

1,60 
1,46 

1,81 

2,79 
1,63 

2,63 

2,57 

+ 
++ 
+++ 

++ 
+++ 
N avoided 
(tons/year) 

54.817 

168. 228 
84.603 

+ 
+++ 
+++ 

+ 
+ 

+ 

+++ 
++ 

215.133 

++++ 

282.524 
(Toxic load 
avoided - areas at 
risk p.e.)  
32.875 

41.836 

41.836 

+++++ 

+ 

+++ 

+++ 
++ 
+++ 

+++ 
+ 

+++ 

+++ 
+++ 

+++ 

+++ 

+++ 

++ 

914 
2.966 
7.754 

19.138 
49.492 

917 

917 
7527 

4.222 

7527 

917 

5.544 

7.527 

43,1 
57,6 
77,2 

0,472 
0,748 

- 

- 
- 

- 

- 

- 

- 

- 

+++++ 

++++ 

Table  13:  Summary  of  the  selection  criteria  applied  for  each  option  –  the  preferred  Options  are  in  green  –  all  costs  and  benefits  are  estimated  by  2040

65 

 
 
 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
  
  
  
  
  
  
  
  
  
  
 
7.  PREFERRED OPTION 

7.1 Preferred Option – summary  

The  main  actions  included  in  the  preferred  option  are  summarised  in  Table  14  below, 
which includes indicative deadlines. On top of the actions included in the Table, by 2025 
additional  monitoring  activities  would  be  in  place:  this  concerns  non-domestic  releases 
(section  6.6),  COVID-19  and  AMR  (section  6.9),  key  performance  operator  indicators 
together with actions to  improve transparency (section 6.8). National and EU databases 
should  be  in  place  (section  6.11)  and  ‘vulnerable  and  marginalised  people’  should  be 
identified together with actions to improve access to sanitation (section 6.10).        

2025 

2030 

2035 

2040 

SWOs and Urban 
Runoff  

 Monitoring in place   

Integrated Plans for 
agglo. > 100.k p.e. 
+ areas at risk 
identified  

Integrated Plans in 
place for 
agglomerations at 
risk between 10 and 
100k p.e.  

Indicative EU target 
in force for all 
agglomerations > 
10.000 p.e.   

Individual 
Appropriate 
Systems  

Regular inspection in 
all MS + Reporting   
for MS with high IAS  

EU standards for 
IAS  

Small scale 
Agglomerations  

New thresholds of 
1.000 p.e. 

All agglo.> 1.000 
p.e. compliant 

Nitrogen and 
Phosphorus  

Identification of areas 
at risk (agglomerations 
10 to 100k p.e.)  

Interim target for 
N/P removal 
facilities > 100.000 
p.e. + New 
standards for N/P  

N/P removal in all 
facilities above 
100k p.e. + Interim 
target for areas at 
risk   

N/P removal in 
place in all areas at 
risk (between 10 
and 100k p.e.) 

Micro-pollutants  

Setting up Extended 
Producer 
Responsibility 
Schemes  

Energy  

Energy audits for 
facilities above 100k 
p.e. 

Areas at risk 
identified (facilities 
10 to 100k p.e.) + 
Interim target for 
facilities above 
100.k p.e. (50% of 
the facilities 
equipped)  

All facilities > 100k 
p.e. equipped + 
interim targets for 
areas 'at risk'(50% 
of the concerned 
facilities between 
10 and 100 k p.e. 
equipped)  

Audits for all 
facilities above 10k 
p.e. (50% of the 
energy neutrality 
target met)   

Interim target for 
energy neutrality 
(75% of the energy 
neutrality target 
met) 

All facilities at risk 
equipped with 
advanced treatment  

Energy neutrality 
met and related 
GHG reduction met  

Table 14: Summary of the key actions included in the preferred option  

By 2040, the impacts of the preferred options are summarised in Figure 16 and in Table 
15 below. Compared to the baseline, the total pollution would be reduced by 4,8 million 
p.e. (or 105.014 tons) for BOD, 56,4 million p.e. for N (or 229.999 tons),  49,6 million 
p.e. (or 29.678 tons) for P, 77,4 million p.e. for toxic load of micro-pollutants and 24,8 
million p.e. for E. coli.  These reductions represent 27% of what is ‘technically feasible’ 
for BOD, 62% for N, 61% for P, 63% for the toxic load of micro-pollutants and 50% for 

66   

 
 
 
 
  
  
  
  
  
E.  coli.  Micro-plastics  emissions  would  be  reduced  by  9%  mainly  through  actions  on 
SWO and urban run-off.  

Preferred option - impacts on Emissions (million p.e.) 

300

250

200

150

100

50

0

BOD

N

P

E. Coli

Micro pollutants

Baseline

Preferred Option (2040)

Maximum feasible

Figure 15: Preferred option – impacts on emissions (p.e. per year in 2040) – a breakdown per 
MS is provided in Annex 7, Table A7.7 

BOD   

N   

P  

E. coli  

-    

-    

2.187.882  

1.455.249  

2.277.889  

1.427.839  

3.448.911  

1.346.247  

52.719.582  

45.873.500  

Storm water and 
urban runoff 
Small 
agglomerations  
Nutrients  
management 
Micro-pollutants 
treatment  
Energy and 
GHG  
Total reduction 
p.e.  
Total reduction 
tons/year)  
Reduction as a 
% of maximum 
feasible  
Table 15: Emission reduction by 2040 – preferred option   

105.014 
27% 

229.999 
62% 

29.678 
61% 

49.579.228 

56.362.713 

4.795.158 

-    

-    

Micro- 
pollutants  

GHG 
reduction  

6.558.744  

2.609.814  

-    

1.391.488  

2.160.989  

3.616.469  

18.979.050  

-    

68.197.761  

24.756.508 

3.472.218     

77.364.162 

4.863.706         

50% 

63% 

With the planed measures to  reach  energy  neutrality, GHG emission would  be reduced 
by  3,472  million  tons  by  2040  compared  to  the  baseline,  or  33,71%  of  the  avoidable 
GHG emissions. Together with  the baseline (assuming GHG emission reduction due to 
the  application  of  the  EED  and  ESR)  and  compared  to  1990,  this  would  represent  a 

67   

 
 
 
 
 
  
  
       
       
       
       
       
  
                     
     
     
     
                     
       
                     
                     
                     
                     
     
  
  
    
    
    
    
       
              
     
     
     
     
    
          
             
             
  
  
 
reduction of 62.51% of the GHG emissions - which is compatible with the EU Climate 
Law and the ‘Fit for 55’ climate package.40  

The annual costs and the annual monetised benefits of the measures included in preferred 
options are presented in Table 3 below. Investments costs are displayed in Table 6.  The 
annual  costs  include  operational  and  investment  costs  taking  into  account  a  lifetime  of 
the investments of 30 years to which a discount rate of 2.5% was applied (see Annex 4 
for more details).41  As from  2040, the total cost would amount to  € 3,793 bn per  year 
(less than 2,76% of the costs of the maximum feasible scenario - € 13,870 bn).  Overall, 
the total costs at EU level (€ 3,848 bn/year in 2040) are below the expected monetised 
benefits (€ 6,643 bn per year by 2040 – of which 6.157 bn are related to improvements 
to  water quality  and 0,486 bn to GHG emission reduction due to  better N management 
and energy neutrality).   

Reduction of 
the toxic load 
of 68.198 p.e. 
Energy 
neutrality 

Costs (€/year)  Administrati

ve costs 
(€/year) 

Total costs 
(€/year) 

Monetised 
benefits 
(€/year) 

Proportionality 
(Benefits/Cost
s)   

372.472.648 

57.600.000 

430.072.648 

785.687.648 

2.11 

140.406.278 

472.000 

140.878.278 

224.242.435 

1,6 

2.008.825.659 

0 

2.008.825.659 

5.285.693.790 

2,63 

1.185.512.586 

27.600.000 

1.213.112.586 

0 

Storm water and 
urban runoff 
Small 
agglomerations  
Nutrients  
management 
Micro-pollutants 
treatment  

Energy and GHG  

  Note42 

347.221.754 

55.700.000 

Others 
(AMR/Covid 
surveillance, non 
domestic waters) 
1,726 
Total  
Table 16: Summary of 2040 costs and benefits of the preferred option and summary of the 
investments needs between entry in force and 2040      

6.642.845.627 

3.707.217.171 

3.848.589.171 

141.372.000 

Proportionality  

The preferred option will  allow emission reductions contributing to  the  achievement of 
the main objective of this review (Objective 1 in section 4) in  a cost-effective way. As 
shown in Table 3, the benefits are higher than the costs for each individual measure of 
the preferred option. For energy neutrality as the financial costs are expected to be more 
than compensated by the financial savings (see section 6.7), only monetised benefits due 

40 According to the EEA, GHG emissions from the sector amounted to 49,2 million tons of CO2eq in 1990 
of which 18,6 can be considered as ‘avoidable’.  
41 In the context of this IA, a net present value analysis was not applied as the investments and most of the 
related benefits will occur progressively and in a linear way between the entry in force and 2040 (no major 
time gaps between investment time and appearance of the benefits).   
42 As detailed in section 6.7, administrative costs related to energy audits (6 million/year) and 
monitoring/reporting energy and GHG emissions (98,7 million/year) as well as investments costs needed to 
reach energy neutrality are expected to be compensated by the financial savings due to improved energy 
efficiency and increased production of renewables.  

68   

 
 
 
 
  
  
 
 
 
 
 
                                                           
to GHG emission reduction are taken into account leading to a positive benefit/cost ratio. 
For  micro-pollutants,  in  absence  of  monetisation  of  the  benefits  (see  section  6.5),  the 
preferred option is  the most cost  effective, leading to  the highest  reduction  of the toxic 
load in particular in sensitive areas compared to the costs of the action.  In summary, the 
preferred  option  includes  a  proportionate  package  of  measures  representing  the  best 
‘value  for  money’  of  all  possible  options:  as  displayed  in  Table  10  and  in  section  6, 
careful attention was given to find an optimal solution based on: 

 

the costs and the benefits analysis (or the cost effectiveness analysis in the case of 
micro-pollutants in absence of monetised benefits): the benefits are higher than the 
costs for all measures and all MS;  

  administrative  burden/enforceability  -  by  targeting  only  a  limited  number  of 
facilities/agglomerations, significant results can be obtained on key parameters such 
as pollution reduction, energy use and GHG emissions while keeping administrative 
burden at a reasonable level and ensuring a high level of enforceability; 

 

the  introduction  of  a  risk-based  approach  will  help  ensuring  that  investments  are 
taking  place  where  they  are  needed  –  this  is  the  case  for  N/P  and  micro-pollutant 
reduction, but also for SWOs/urban run-off.     

When necessary to reach local optimal solutions, flexibility was left at national or local 
levels.  This  is  the  case  for  instance  to  achieve  the  objective  of  energy  neutrality  or  to 
reduce emissions from SWOs.  

If  the  costs  are  relatively  well  known  and  quantified,  this  is  less  the  case  for  some 
benefits: reliable monetised values are only available for a limited set of parameters such 
as direct savings from energy use, GHG emissions, BOD, N and P emission to water but 
also recent estimates of the benefits from improved management of SWO and urban run-
off (see section 6.1). Some benefits can be quantified but not monetised: this is the case 
for instance for micro-pollutants and micro-plastics (no available shadow prices) but also 
reduction of E.coli in waters (leading to more possibilities of bathing areas for instance). 
Other  significant  benefits  were  impossible  to  quantify  due  to  the  lack  of  proper 
methodologies:  this  is  the  case  for  access  to  sanitation  and  health  related  parameters 
(COVID-19 and its variants and AMR surveillance) but also the benefits linked treatment 
cost reduction for drinking waters producers due to improved quality of surface water.  

Costs coverage  

The  total  costs  by  2040  would  represent  an  increase  of  3,85%  of  the  current  total 
expenditures for water supply and sanitation (around 100 bn € - OECD (2020) – Annex 
10, report 5). These additional expenses would be partly covered by the new EPR system 
–  €  1,213  billion/year.  The  remaining  part  –  2,64  billion/year  -  would  be  covered  by  a 
mix of water tariffs and public budgets, depending on the financing strategies applied by 
each MS. On the basis of the current  financing strategies of the MS (see Figure 10), it 
can  be  assumed  that  on  average  30%  (or  €  0,791  billion/year)  of  the  additional  costs 
would  be  covered  by  public  budgets.  70%  (or  €  1,848  billion/year)  would  then  be 
covered  by  water  tariffs.  This  would  represent  an  average  modest  increase  (2,3%) 
compared  to  the  overall  water  billing  on  the  EU  (80  billion  for  water  supply  and 
sanitation in 2018 – source OECD, Annex 5, report 6), even if local/national difference 
might  be  excepted.  EU  funds  (around  2  bn/year  for  the  water  sector)  would  remain 

69   

 
 
 
 
indispensable to cover adjustment costs needed to cover the new requirements including 
energy neutrality.   

Impacts at MS level 

The total 2040 cost and benefits for each MS is displayed in Annex 7, Table A7.8 and 9. 
Figure 2 shows that  –  even without taking account  of the non-monetised benefits  from 
micro-pollutants reduction - the benefits largely outweigh the costs in all MS.   

Preferred Option - Costs and Benefits per MS 

1400

1200

1000

800

600

400

200

0

AT BE BG CY CZ DE DK EE EL ES FI FR HR HU IE IT LT LU LV MT NL PL PT RO SE SI SK

Total benefits (Million €/year) 

Total costs (Million €/year)

Figure 16: Costs and benefits of the preferred option  

As displayed in Figure 16, some MS (e.g. DK, IT, MT, CY and PT) would have to make 
comparatively more efforts per inhabitant (more than 7 €/year/inhabitant by 2040). This 
is  due  to  a  combination  of  objective  factors  including  the  lack  of  past  investments  in 
more  advanced  water  treatment  for  Nitrogen  and  Phosphorus,  but  also  geographical 
circumstances (low dilution rates across freshwater streams increasing the areas ‘at risk’). 
Although  the  costs  for  these  MS  are  expected  to  be  slightly  higher,  the  benefits  are 
nonetheless expected to remain higher than costs in all cases.    

70   

 
 
 
 
 
Costs and Benefits per inhabitant by 2040 (€/person/year -
without micro-pollutants)

35,00

30,00

25,00

20,00

15,00

10,00

5,00

0,00

AT BE BG CY CZ DE DK EE EL ES FI FR HR HU IE IT LT LU LV MT NL PL PT RO SE SI SK

Total cost €/year/inhab

Total benefits €/year/inhab

Figure 17: 2040 Annual costs and benefits per inhabitants per Member State (excluding costs 
for micro-pollutant treatment to be covered by the proposed EPR scheme)   

Figure  18  displays  the  2040  costs  of  advanced  treatment  per  MS  in  relation  to  the 
reduction of the toxic load from wastewater treatment plants. Differences between MS in 
terms  of  additional  investment  needed  can  be  explained  by  the  presence  of  more  areas 
considered ‘at risk’ for micro-pollutants (with lower dilution rates).  

Preferred Option - Micro-pollutants 

300

250

200

150

100

50

0

80

70

60

50

40

30

20

10

0

AT BE BG CY CZ DE DK EE EL ES FI FR HR HU IE IT LT LU LV MT NL PL PT RO SE SI SK

Cost reduction toxic load (Million €/year)

Reduction toxic load (%) In waste water plants

Figure 18: 2040 costs of advanced treatment vs toxic load reduction (micro-pollutants in waste 
treatment plants)  

Social impacts - Affordability  

According to OECD, today the general affordability of water services is not at risk in any 
country,  though  in  some  countries,  such  as  RO  and  BG,  the  burden  borne  by  lower 
income households is slightly higher than in other MS, being above 5% of the disposable 
household income – see Figure 19.  

71   

 
 
 
 
 
 
Figure  19:  Share  of  water  supply  and  sanitation  expenditures  in  households'  disposable 
income (2011-2015 average) Source: OECD based on Eurostat43  

Social measures to accompany lower income households are in place in several MS – but 
not systematically in the whole EU. Nevertheless, particular attention should be paid to 
some MS (DK, IT, MT, CY and PT) in which annual costs per inhabitants are expected 
to  be  higher  see  Figure  18.  Affordability  is  not  expected  to  become  an  issue  in  any  of 
these  MS:  the  average  expected  increase  of  water  tariffs  by  2040  due  to  the  preferred 
option would amount to 1,6 €/year/inhabitant (CY) to 7,26 €/year/inhabitant for DK. As 
shown in Table 17 below and based on OECD data as displayed in Figure 19, compared 
to  the  lowest  5%  income  in  each  country,  this  would  represent  a  small  increase  of  the 
budget  devoted  to  water  supply  and  sanitation  (between  0,02%  for  CY  and  0.19%  for 
PT).  Therefore,  the  share  of  expenditures  due  to  water  supply  and  sanitation  for 
households  with  poorest  revenues,  would  remain  below  5%  -  which  is  the  ceiling 
considered as acceptable by OECD.  

Practical  measures  to  ensure  affordability  is  mainly  a  competence  of  the  MS  but  the 
Commission can organise further exchange of best practices notably on social measures 
in the water sector in continuation of the seminars co-organised with the OECD and the 
MS (see report 5 in Annex 10).   

43 Note: Lack of household expenditure data for Croatia and Sweden.  

72   

 
 
 
 
 
 
 
  
                                                           
Total 
additional 
cost 
€/year/inhab 

Water 
tariff 
coverage 
% 

To be 
covered 
by water 
tariff 

5% lowest 
income 
(€/year) 

New total 

Cost to 
lowest 5% 
income 

Tariff 
increase as 
% of the 
5% lowest 
income  

21,80% 

1,59 

6860 

0,02% 

0,86% 

0,88% 

98,60% 

7,26 

11998 

0,06% 

1,92% 

1,98% 

CY 

DK 

IT 

7,29 

7,36 

6,84 

82,40% 

5,64 

MT 

11,34 

55,60% 

6,3 

PT 

7,29 

75,00% 

5,46 

4421 

5461 

2819 

0,13% 

3,68% 

3,81% 

0,12% 

1,81% 

1,93% 

0,19% 

3,00% 

3,20% 

Table  17:  analyse  of  affordability  in  MS  with  highest  cost  per  inhabitant  (source:  OECD 
reference5 in Annex 10 and Figure 25 of the REFIT Evaluation    

Implementation  

As it was the case with the existing Directive (refer to the REFIT Evaluation), there will 
be risks of slow or bad implementation of the revised Directive in some MS. These risks 
would nevertheless be mitigated with the following measures:   

  Contrary  to  the  initial  Directive,  enough  time  (2040)  would  be  given  to  meet  the 
targets of the revised Directive. This time horizon will provide legal certainty so that 
investments can take place on the basis of proper long term planning;  

  Interim  targets  will  be  included  in  the  legislative  proposal  for  the  most  important 
measures. These interim targets are summarised in Table 1 and will be applied for all 
MS. They will help MS to plan their investments sufficiently in advance and avoid a 
situation were most of the actions are taken few years before 2040; the interim target 
for  energy  neutrality  and  for  tertiary  treatment  will  take  into  account  the  starting 
position of each MS;  

  The  expected  effects  on  public  budgets  and  water  tariffs  (and  therefore 
affordability of the water tariffs) are modest while EU funds would remain available 
(average of 2 bn/year based on past experience);  

  The  Commission  intends  to  continue  its  mixed  approach  (enforcement  combined 

with EU funds) which has shown its effectiveness in the past; 

  Several aspects of the Directive will be clarified with the revised Directive (‘sensitive 
areas’, measures on SWO/urban run-off, better control of IAS) while the simplicity of 
the text would be kept (clear and simple requirements with clear deadlines).      

In  addition,  and  like  it  was  the  case  for  MS  having  joined  the  EU  after  2004,  those 
Member  States  still  having  difficulties  to  reach  full  compliance  today  will  have  the 
opportunity to invest directly in most advanced techniques.   

Coherence and added value of the initiative  

Implementing  the  preferred  option  would  contribute  either  directly  or  indirectly  to  the 
attainment of the objectives of several EU strategies and legislations – see Annex 8 for 

73   

 
 
 
 
  
more  details.  This  is  the  case  for  the  Zero  Pollution  ambition  (reduction  of  pollutant 
releases  in  the  waters),  the  2050  EU  Climate  neutrality  objective  and  the  related  EU 
Climate  law  (reduction  of  GHG  emissions  due  to  energy  neutrality),  the  Circular 
Economy  (better  use  of  resources/sludge,  better  conditions  for  water  reuse),  the 
Biodiversity  Strategy  (green  infrastructures)  and  the  Pharmaceutical  and  the 
Chemical  strategy  (less  releases  of  pharmaceuticals  in  the  environment,  financial 
incentive  for  substitution  of  harmful  substances).  Reducing  nutrient  emission  will 
directly contribute to the preservation of the Biodiversity. In addition, direct synergies 
can be excepted withy the Biodiversity strategy and the application of nature restoration 
targets in urban areas (nature based solution for better water management in urban areas).  

As  it  was  already  the  case  with  the  existing  Directive  (see  the  Evaluation),  the  revised 
Directive would directly contribute to achieving the objectives of the Water Framework 
Directive – namely reaching the good ecological and chemical status of water bodies by 
2027.  It  would  also  contribute  to  the  planned  revision  of  the  EQS  Directive:  the 
additional  treatment  of  micro-pollutants  would  allow  the  attainment  of  more  stringent 
EQS in the environment. This also the case for the ongoing review of the Bathing Water 
Directive:  reinforcing  the  standards  of  the  UWWTD  particularly  for  SWO  and  urban 
runoff  would  contribute  to  the  improvement  of  the  quality  of  the  bathing  water.  Better 
controlling  pollution  at  source  would  help  to  ensure  a  safe  use  of  sludge  in  agriculture 
and  thus  support  the  ongoing  review  of  the  Sewage  Sludge  Directive  and  the  Soil 
Strategy and the proposal for the Soil Health Law. It will also provide an incentive for 
more  and  better  re-use  of  treated  water  contributing  to  improve  water  resilience. 
Synergies  will  be  fully  exploited  with  the  ongoing  review  of  the  E-PRTR  Directive 
notably  for  what  relates  to  reporting  for  the  larger  facilities.  Coherence  between  the 
revised IED and UWWTD will be improved to avoid non desirable industrial releases in 
public networks. 

The energy neutrality target would act in synergy and complement with the revised RED 
and  recast  EED  by  contributing  to  meet  the  targets  of  each  of  these  directives  in  an 
optimal way for each wastewater treatment facility combining energy efficiency, use of 
renewable  energy  and  production  of  biogas.  By  encouraging  the  self-production  of  EU 
based biogas, it would also contribute to reduce energy dependency, one of the objectives 
of the  recently  adopted  Communication ‘Repower EU’.  Last  but  not  least,  this sectoral 
target  would  help  moving  towards  the  EU  objective  of  climate  neutrality  by  2050  and 
contribute  to  the  implementation  of  the  ‘Fit  for  55’  and  the  ESR  (expected  GHG 
emission reduction of 3,472 million tons (33,71% of the avoidable GHG emissions) by 
2040 compared to the baseline which assumes the application of the revised EED. 

Regular  monitoring  of  COVID-19  and  its  variants  and  other  health  related  parameters 
will  help  to  improve  the  preparedness  of  the  EU  for  future  possible  outbreaks  –  as 
detailed in the related Communication and in the Commission recommendation  on virus 
surveillance in wastewaters.   

74   

 
 
 
 
 
 
 
 
Uncertainties  

The main uncertainties are summarised in Table 18. More details on model uncertainties 
are provided in Annex 4.  

Uncertainty 

Measure taken to identify/limit 
uncertainties 

How it was taken into account in policy 
development? 

Baseline – lack of 
understanding of MS 
existing actions on 
rain water, small 
agglo., IAS  

Baseline – lack of 
information on how 
MS will apply the 
EED, RED and ESR  

In depth consultation of the MS 
on their starting positions – 
Annex 5. 

No major influence. Costs and benefits per MS 
might be slightly different but are linked (if 
costs for a MS increase or decrease, benefits will 
also increase or decrease).    

Prudent assumption taken in the 
baseline based on the best 
existing available information 
(strict application of the energy 
use reduction target from the 
EED proposal for the public 
sector across all MS) 

Applying the proposed energy neutrality target 
will generate more savings, benefits and GHG 
reduction in MS not having initially the 
intention to act in the wastewater sector to reach 
their targets under the RED, EED and ESR. The 
reverse impacts are expected in MS having 
already targeted this sector. Overall at EU level 
it would not change the analysis neither the 
conclusions on the added value of the energy 
neutrality target. 

Unknown starting 
positions of the MS in 
terms of energy 
neutrality  

Very conservative assumptions 
were taken on the cost and 
benefits of reaching energy 
neutrality  

Interim targets were fixed by 2030 to allow MS 
with a less favourable starting position to align 
themselves with the others. MS starting with a 
less favourable position are expected to gain 
more benefits from the energy neutrality target.   

Different starting 
situations for SWO 
and urban runoff. 

Development of an EU scale 
model calibrated on known 
situations.   

Flexibility left to MS and their local authorities 
to design optimal solutions at local level. 

Lack of reliable to 
monetise micro-

pollutants benefits.    

The preferred option was 
identified on the basis of cost-
effectiveness.  

Options were decided on the basis of lowering 
the costs while maximising the toxic load 
reduction.   

Lack of data on the 
actual toxicity of 
micro-pollutants, as 
well as their removal 
efficiency by standard 
techniques.  

The best available data and 
scientific knowledge was used to 
make estimates – see Annex 10 
reports 2, 13 and 14.  More than 
1.300 representative chemicals 
were assessed giving a fair 
representation of the toxic load 
and how it can be reduced. 

Advanced treatment is required to reduce 
toxicity, independent of the specific chemicals. 
The comparison of policy options is robust with 
regard to the variation of chemical properties 
driving toxicity. The introduction of a possible 
EPR scheme will help to gather precise data. 
The scope of the EPR scheme can be adapted to 
improved knowledge on micro-pollutants.    

Table 18: Main uncertainties and their potential consequences   

75   

 
 
 
 
 
The sector is relatively well known, reliable databases are in place on all treatment 
facilities above 2.000 p.e. including on their level of treatment. The estimation of 
conventional pollutant loads under the various scenarios, and the related costs are 
relatively well established and show relatively low variability across Europe. The main 
uncertainties are related to the estimation of toxic loads conveyed by wastewater and to 
the sources of pollution not addressed by the current Directive. There are also 
uncertainties related to the application of the ESR, the RED and the EED current and 
revised legislations. 

7.2 REFIT and “One in, One out”  

In line with the Evaluation,  several  elements  of the existing Directive will be  clarified 
and simplified in the legislative proposal on the basis of the elements discussed in this 
IA. This  concerns notably  the requirements  for SWO and urban runoff and small  scale 
agglomerations (clear thresholds and deadlines), the designation of ‘sensitive’ areas (list 
of basins placed in the Annex of the revised Directive), clearer obligations to ensure full 
compliance  for  IAS,  and 
transparency  of  operator’ 
improved  follow-up  and 
performances.  For  the  new  requirements,  a  lot  of  attention  has  been  paid  to  establish 
simple,  clear,  enforceable  and  affordable  deadlines  and  objectives  –  the  Evaluation  has 
demonstrated the importance of clarity and enforceability of this Directive.  

Apart from the expected increase in water tariffs, no additional obligations are expected 
for EU citizens. This is also the case for business (water industry providing wastewater 
equipment’s)  which  will  mainly  benefit  from  new  business  opportunities.  The  new 
requirements  will  represent  a  driver  for  innovation  and  research  contributing  to 
maintain  and  improve  the  competitive  position  of  the  EU  water  industry.  The 
Pharmaceutical and PCPs sectors would nevertheless be required to organise and finance 
the  new  system  of  producer  responsibility  to  cover  the  costs  related  to  advanced 
additional  treatment  for  micro-pollutants  (1,185  bn  €  per  year)  and  the  related 
administrative costs (11,2 million per year – see section 6.5).     

The revised Directive will introduce new obligations mainly for wastewater operators. 
They cannot be considered as ‘business’ as all operators have strong direct links with 
the  public  competent  authorities  –  either  they  are  public  companies  (60%  of  the 
operators) or private/mixed companies directly acting for public entities (concessions).   

Measure of the 
preferred 
option 

Storm water 
and urban 
run-off 

Small 
agglomerations 

Nutrients  
management 

Micro-
pollutants 
treatment 

Total 

Total 
investment up 
to 2040 

6.446.657.281 

1.141.228.243 

12.129.508.400 

8.891.344.396  28.608.738.319 

Table 19: Total investments costs linked with the preferred option between entry in force and 
2040.  To  calculate  annual  costs,  a  lifetime  of  the  investments  of  30  years  was  applied  with  a 
discount rate of 2.5% (see Annex 4 for more details). 

Adjustment costs to  cover the required investments  needed to  meet  the  new standards 
and  to  reach  energy  neutrality  will  be  progressive  in  time  (see  Table  14  and  Table  16): 
total  investment  costs  are  estimated  at  €  28,6  billion  between  the  entry  in  force  of  the 

76   

 
 
 
 
revised Directive and 2040 – see Table 19. In absence of sufficient data on the baseline 
situation  in  each  MS  on  energy  neutrality,  it  was  not  possible  to  provide  a  reliable 
estimation of the investments needs for this measure.  

To cover these investments, MS and local competent authorities are expected to continue 
using a blend of different sources of financing:    

  Public budgets, including from the EU (e.g. around 2 billion € per year of EU funds 

are devoted to water infrastructures, particularly under EU regional policy); 

  Loans  from  commercial  or  institutional  banks  (such  as  the  European  Investment 
Bank) – wastewater projects are typically ‘bankable’ as they are covered by stable 
revenues from water tariffs and/or energy savings;  

  Private/public  partnerships  and/or  concessions  in  which  the  private  partner  is 

financing the infrastructures.  

  The investments needed for the additional treatment for micro-pollutants (9 billion € 
up  to  2040  from  the  total  28,6  billion  €)  will  be  covered  by  the  EPR  scheme,  and 
more  precisely  by  the  Producer  Responsibility  Organisations  (PROs)  managing 
them.  As  detailed  in  section  6.5,  the  PROs  will  have  to  establish  a  solid  financing 
strategy to cover such costs based on the funds gathered thanks to the fees paid by its 
members.  

  The recently adopted REPowerEU Plan will also boost existing funding possibilities 
to cover the investments needs to reach energy neutrality. This concerns the cohesion 
policy,  large  scale  innovation  calls,  loans  under  Recovery  and  Resilience  Facility. 
MS already have and will have several possibilities to cover the investments needed 
to meet energy neutrality target through these EU funds as they all aim at increasing 
the independence of the EU in terms of energy supply by encouraging energy savings 
and developing renewables – which is also one of the purpose of the energy neutrality 
target.      

8.  HOW WILL ACTUAL IMPACTS BE MONITORED AND EVALUATED? 

As  shown  in  the  Evaluation,  proper  monitoring  and  reporting  is  key  to  ensure  the 
compliance  of  the  Directive.  It  is  therefore  crucial  to  maintain  and  improve  where 
possible  the  existing  monitoring  and  reporting  obligations  so  that  it  will  be  possible  to 
assess to what extent the general and specific objectives are achieved.    

The existing Directive has established a reporting system based on a 2-year report from 
the  MS  to  the  Commission  via  the  EEA.  Based  on  this  information  the Commission  is 
publishing implementation reports every two years (often based on more than 4 years old 
data). The Commission is also using this information to launch infringement procedures.  

As detailed in sections 5 and 6, this system will be modernised and simplified: national 
databases to be updated at least once a  year will be hosted in each MS with permanent 
access for the EEA and the Commission. These databases will include actual monitoring 
results for the parameters covered by EU standards not only for the quality of the treated 
water  but  also  for  the  new  parameters  to  be  followed  such  as  energy  use  and  GHG 
emissions. Monitoring frequencies will also be adapted to ensure an appropriate follow-

77   

 
 
 
 
up  of  the  implementation  of  the  Directive  but  also  to  simply  align  the  frequencies  to 
current best practices.  

As it is the case today, regular compliance checking will be made by the Commission on 
the basis of the information reported by MS.   

Different indicators to measure success can be extracted from MS reports and would be 
related to: 

  The existing compliance rate and distance to target per MS and per treatment level - 

which provide an excellent overview on the implementation of the Directive;   

  The  number  of  facilities  equipped  with  additional  treatment  for  N/P  and  micro-
pollutants;  and  the  related  reduction  of  N/P  releases  and  toxic  load  at  MS  and  EU 
levels;  

  The energy use by MS and the related GHG emissions;  

  The  number  of  agglomerations  covered  by  integrated  management  plans  for 
stormwater overflows and urban run-off and their compliance with the EU objective;  

  The  measures  taken  by  MS  to  improve  access  to  sanitation  and  better  control 
individual  appropriate  systems  (IAS)  and  a  summary  of  the  main  health  indicators 
surveyed in the MS.     

Like it was the case in the context of the evaluation of the Directive, other data notably 
on  the  water  quality  of  the  receiving  waters  (rivers,  lakes  and  seas)  coming  from  the 
Water  and  the  Marine  framework  Directives  will  be  used  to  concretely  measure  the 
impacts of the UWWTD.  

More details on possible parameters to be reported for assessing compliance and measure 
the success of the Directive are provided in Annex 10.  

A first in depth evaluation of the revised Directive can be foreseen by 2030 when most 
investments should have been made in larger facilities (see Table 1). This first evaluation 
would  allow  assessing  the  success  and  remaining  challenges  linked  with  the 
implementation  of  the  revised  Directive.  If  need  be,  corrective  measures  could  be 
envisaged to ensure the full implementation of the revised directive. Another evaluation 
could be considered before 2040 to prepare a possible review of the directive.  

78   

 
 
 
 
 
 
 
ANNEX 1: PROCEDURAL INFORMATION 

1.  LEAD DG, DECIDE PLANNING/CWP REFERENCES 

The preparation of this impact assessment was led by Unit C2 Clean Water Services and 
Marine  Environment  within  DG  Environment  (ENV)  with  support  from  DG  Joint 
Research D2 Water and Marine Resources. The file concerns the revision of the Urban 
Wastewater  Treatment  Directive.  This  Directive  was  evaluated  according  to  Better 
Regulation  guidelines  in  2019.  The  Decide  planning  number  is  Plan/2020.7347  – 
Revision of the Urban Wastewater Treatment Directive.  

2.  ORGANISATION AND TIMING 

The  revision  of  the  Urban  Wastewater  Treatment  Directive  (UWWTD)  is  a  direct 
consequence  from  its  REFIT  evaluation.  It  was  announced  in  a  number  of  strategies 
published  under  the  European  Green  Deal,  such  as  the  Circular  Economy  Action  Plan 
(CEAP) and confirmed  more recently in  the  Zero Pollution Action Plan. The  Inception 
Impact Assessment Roadmap for the revision of the UWWTD was published on 21 July 
/2020 with a feedback period until 8 September 2020.  

The inter-service steering group (ISSG) for the impact assessment is the same one as for 
the  Evaluation.  It  is  a  shared  group  with  other  water  and  pollution  related  files:  the 
revision of the pollutant lists under the EQSD and Groundwater Directive, the Evaluation 
of the Sewage Sludge Directive and the back to back Evaluation and impact assessment 
of  the  Bathing  Water  Directive.  The  ISSG  includes  members  from  the  following  DGs: 
AGRI  (Agriculture),  CLIMA  (Climate  Action),  ENER  (Energy),  FISMA  (Financial 
Stability,  Financial  Services  and  Capital  Markets  Union),  GROW  (Internal  Market, 
Industry,  Entrepreneurship  and  SMEs),  HOME  (Migration  and  Home  Affairs),  JRC 
(Joint  Research  Centre),  JUST  (Justice  and  Consumers),  MARE  (Maritime  Affairs  and 
Fisheries),  RTD  (Research  and  Innovation),  REGIO  (Regional  and  Urban  Policy), 
SANTE (Health and Food Safety), SG (Secretariat General), SJ (Legal Service), TAXUD 
(Taxation and Customs Union) as well as the EEA (European Environment Agency). 

including 

Meetings were organised between June 2020 and January 2022, the final meeting being 
held on 31st January 2022. The ISSG has been consulted on all major deliverables for this 
the  open  public  consultation 
impact  assessment, 
file, 
questionnaire,  key  deliverables  for  the  support  study  prior  to  the  its  submission  to  the 
Regulatory Scrutiny Board. The same ISSG has followed the while process having led to 
the adoption of the REFIT Evaluation of the Directive.  

inception 

the 

3.  CONSULTATION OF THE RSB 

The Regulatory Scrutiny Board (RSB) was consulted on the Evaluation of the Directive.  

On 17 July 2019 the RSB meeting on the draft SWD Evaluation was held. The RSB gave 
a positive opinion on 19 July 2019 and suggested a few improvements which were taken 
on board before the finalisation and publication of the evaluation.   

An informal upstream meeting with the RSB took place on 23 September 2020 on the IA. 
During the meeting ENV explained that the options will be built into packages that range 
from  less ambitious to more ambitious. The costs  and benefits  of each package will be 

79   

 
 
 
 
assessed  as  far  as  possible.  They  should  all  aim  to  meet  all  objectives  of  the  initiative. 
RSB suggestions and answers provided in this IA are summarized in Table 7.  

After  final  discussion  with  the  ISSG,  a  draft  IA  was  submitted  to  the  RSB  on  15th 
February 2022 and discussed at a meeting with the RSB on 16th March 2022. Following 
the opinion of the RSB from 18th March 2022, a revised IA was submitted to the Board 
on 2nd of May. A second ‘positive opinion with reservations’ was issued by the RSB on 
3rd of June. Table A1.1 presents an overview of the RSB's comments and how these have 
been addressed.) 

RSB Comment – second Opinion  

How the comment has been addressed 

(1) The report does not present a fully developed 
and dynamic baseline scenario. It is neither 
sufficiently clear how the measures expected from 
the Member States to meet their national ‘Fit for 
55 targets’ nor how the recent actions under the 
Repower EU package have been incorporated and 
which overall energy saving gap would remain in 
absence of further sector specific action and 
targets.   

(2) The report does not sufficiently demonstrate 
the need for and value-added of new sector 
specific energy neutrality targets over and above 
the already envisaged obligations for Member 
States. 

Section 5.1 has been improved to better explain that 
all possible efforts have been made to build a 
dynamic baseline and why the only reliable 
mandatory quantitative target applicable for this 
sector is the legally binding target on energy 
efficiency for public entities (reduction of energy 
use of 1,7% per year for the public sector). This 
target was included in the calculations of the 
baseline scenario as displayed in the new Table 3 of 
section 5.1. It was also better explained that no 
quantified precise information is available on 
Member States intended efforts to reduce GHG 
emissions from the wastewater sector in order to 
reach the objectives of the Fit for 55 and the ESR 
regulation. The potential effects of the REPowerEU 
Plan (adopted after the submission of this report) are 
discussed in section 5.1 on the baseline scenario and 
in sections 7.1 and 7.2. The REPowerEU plan does 
not include specific objectives for the wastewater 
sector as such therefore only its qualitative effects 
on the baseline scenario are presented in section 5.1. 
Nevertheless, the preferred option will contribute to 
achieve the objectives of the package by reducing 
energy use and increasing the production of 
renewables including biogas. This is better 
explained in section 7.2.      
The need and the added value of this specific target 
are better explained respectively in sections 5.2.7 
and 6.7 - Tables 10 and 11. The contribution of this 
target to the attainment of different EU objectives is 
better discussed in section 7.1 while the flexibility 
on Member States choices are discussed in section 
5.2.7. More details are provided on how the costs to 
reach energy neutrality were estimated and why the 
extrapolation made on the basis of the Danish 
concrete and successful experience is reliable and 
provide a robust base to justify the target in the 
context of this impact assessment. It is also better 
explained why the recent increase in energy prices 
makes the assumptions taken in this report (expected 
costs will be covered by the expected financial 
savings) even more realistic and probably too 
prudent.  More details on stakeholder views are 
provided in the same section - recent information 
and contributions from industry were also included.  
More explanations in section 5.2.7 and 7.1 (Table 14 
and section on implementation) are provided to 

80   

 
 
 
 
 
 
(3) The report does not sufficiently justify the 
proportionality of individual measures as well as 
of the preferred option considering the estimated 
investment needs.  

Expected overall investment needs seem to 
substantially outweigh monetised benefits. The 
report should explain whether it can be reasonably 
assumed that all Member States will cover these in 
a timely manner (including those less reliant on 
water tariffs). It should be explicit about whether 
there are any risks for the implementation of the 
measures and for benefits materialising.  

The report should better demonstrate the 
proportionality of the preferred option, preferably 
on the basis of a net present value analysis. When 
it comes to the proportionality assessment of the 
stormwater overflow options, the report should 
better justify why it did not choose, as preferred 
option, the one, which provides the highest net 
benefits overall, performs best in terms of 
effectiveness and enforceability and has the most 
favourable benefit-cost ratio.  

When assessing the proportionality of imposing 
energy neutrality targets, the report should better 
reflect the relative small contribution to the overall 
monetised benefits and the uncertainty that the 
targets will be the most costefficient measure 
among those available for the Member State 

The report should better explain the robustness 
and validity of the used evidence on the 
willingness to pay. It should justify why, in order 
to extrapolate to EU level, it assumes 10% of the 
value determined for the case study of Berlin in 
terms of public willingness to pay for ecosystem 
services associated with drainage. As willingness 
to pay depends on income, the report should 
explain why it did not consider a comparison of 
Germany’s GDP and the EU average or other 
means of extrapolating. 
The report provides more information in an annex 
regarding the proposed extended producer 
responsibility scheme. It should be explicit about 
whether there are any choices for policy makers in 
this regard and if so, present them in the main 
report. 
The report provides stakeholder views without any 
numbers (either percentages or 3 absolute 
numbers). This presentation may be misinterpreted 
as a representative survey which is not the case. 
The report should be more specific on the views of 
particular categories of stakeholders and Member 
States, including by explaining why certain 
academics, business or Member States authorities 

justify how the interim target would be fixed while 
the Table 18 on uncertainties was completed to 
discuss the possible effects of different starting 
positions of MS as regards energy neutrality.   
Table 16 and section 7.1 were improved to show 
that for each of the proposed individual measure in 
the preferred option the annual benefits are 
systematically higher than the annual costs (except 
for micro-pollutants for which a cost/effectiveness 
approach was used). In that sense, all individual 
measures are justified in terms of proportionality. In 
section 7.1 (implementation), more details are 
provided on the measures taken to limit the risks of 
non-timely implementation of the preferred option 
by the MS. Those MS less reliant on water tariffs 
are also those having more margins to increase their 
water tariffs without affecting affordability. 

A footnote (41) was added to explain an NPV 
analysis is not relevant in this context and the 
justification for the preferred option on stormwater 
overflow (most cost effective) was clarified in 
section 6.1.  

The uncertainties related to the energy neutrality 
target were better identified in Table 18, section 7.1. 

More details are provided in section 6.1 on why the 
10% assumption applied the willingness to pay from 
the Berlin case is reasonable in the context of this 
IA.    

The main choices to be done by policy makers were 
explicitly summarised in section 6.5. 

More efforts were achieved in the report to better 
summarise and quantify where possible stakeholder 
views. It was not always possible to verify during 
the consultation some more precise assumptions or 
issues like the calculations made on the costs and 
the financial benefits of reaching energy neutrality.   
There was nevertheless a broad consensus on the 
need to act with a combination of measures 

81   

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
were less supportive on some issues. 

including better monitoring, audits, energy 
efficiency with less overall support for EU based 
targets.  

RSB Comment – first Opinion  

How the comment has been addressed 

(1) The report should be clearer about how the 
initiative fits in the context of existing legislation 
and initiatives. It should explain the coverage of 
each of these and identify the remaining gaps that 
the revised Directive would be expected to 
address. 

(2) The report should explain clearly the evidence 
base for considering sector-specific Energy 
Neutrality Targets and further measures related to 
Green House Gas emissions. It should be specific 
on the scale of the identified Green House Gas 
emission reduction and energy savings gaps under 
the dynamic baseline, fully reflecting the impacts 
expected from the requirements of the Effort 
Sharing Regulation, the Energy Efficiency 
Directive and other relevant ‘Fit for 55’ initiatives. 
It should explain how the new targets and 
measures are expected to interact with the ‘Fit for 
55’ initiatives, how double regulation will be 
avoided and flexibility for Member States on the 
choice of the best measures in reaching their 
overall reduction targets will be ensured. It should 
better justify the 2040 time horizon used for the 
baseline, given the need to ensure coherence with 
the 2050 climate neutrality objectives and the 
envisaged measures in the adopted ‘Fit for 55’ 
package. 

(3) When it comes to micro-pollutants, the report 
should further elaborate on the Extended Producer 
Responsibility scheme it considers. It should set 
out the main elements and present the key policy 
choices to be made by policy makers (e.g. scope, 
progressive expansion) and assess the costs and 
benefits of available alternatives. 

(4) The report needs to strengthen its narrative 
significantly and the argumentation in support of 
the proportionality of the preferred set of 
measures, in particular on SWOs and urban runoff. 
It should make an effort to further quantify the 
expected, most significant, benefits. Where this is 
not possible, the report should explain why and 
provide qualitative analysis to support the 
conclusion that the benefits overweigh the costs. It 
should provide more convincing arguments to 
show how the intervention is expected to bring 

Sections 1 (introduction) and 7.1 (preferred options) 
were improved and completed by a summary Table 
in a new Annex 8 displaying the main interactions 
with other legislations. In addition in each ad hoc 
section the gaps of the existing legislation are 
discussed as well as the potential added value of the 
initiative.  
On GHG emissions, sections 5, 6 and 7.1 have been 
clarified to better explain the interactions with the 
exiting initiatives (Climate Law and by the Effort 
Sharing Regulation). It was clarified that the 
revision of the UWWTD does not have the ambition 
to set any additional legally binding target for GHG 
reduction. The justification of a sector based energy 
neutrality target is further detailed in the IA in 
sections 1 (introduction), 2.1.2.2 (problem 
definition), 5.1 (baseline), 5.2.7 (options), 7.1 
(preferred option) and further detailed in a new 
annex 8. 
This includes an analysis of the added value of a 
sectorial target compared with the baseline including 
the application of the EED and ESR (additional 
reduction of energy use and related reduction of 
GHG emission from the sector but also development 
of local optimal solutions combining energy 
efficiency, renewables and bio-gas production). The 
contribution of this target to the EED and ESR is 
better explained as well as its added value in the 
context of the recently adopted ‘Repower EU’ 
Communication in section 6.7. The justification for 
the 2040 horizon (the main objective and main 
investments of this initiative are related to water 
quality improvement) is better explained in the 
introduction of section 6.    
More detailed explanations on the envisaged EPR 
system (scope, policy choices, possible alternatives, 
costs and benefits) were included in sections 5.2.5 
and 6.5 although more details on the functioning of 
the EPR scheme were provided in a new Annex 9. 
The possible impacts of an alternative based on a 
‘classical’ financing system is discussed in section 
6.5.  
New evidence based on recently published articles 
were included in section 6.1 showing (1) how costs 
could be  reduced with good integrated management 
plans and digitalisation and (2) new estimates of the 
potential benefits based on ‘willingness to pay’ 
beyond water quality of improved storm-water 
overflows management. In addition, more flexibility 
was introduced (EU objective would become 
indicative leaving more flexibility at local level 
while focusing actions only in areas ‘at risk’) so that 
optimal solutions would be decided at local level 

82   

 
 
 
 
 
 
about the non-monetised benefits and the extent to 
which this will happen. It should show the order of 
magnitude (e.g. case studies, expert estimates, 
literature) of the benefits expected to materialise. 
It should present a more balanced analysis of 
benefits and costs, fully reflecting the recurring 
and the (quite high) one-off investment costs. For 
‘one in one out’ approach, it should only include 
the costs to businesses and citizens. 

based on decentralised analysis of the costs and the 
benefits. This has reduced the investment needs 
while increasing the benefits leading to an 
improvement of the proportionality of the measure. 
In consequence, the proportionality of the whole 
package has improved and is better demonstrated in 
section 7.1 (preferred option).  The benefit/cost ratio 
is largely positive for all MS. Section 7.2 (One in, 
One out) was adapted to only focus on costs for 
citizens and businesses.   
Additional information on the impacts on MS were 
extracted from annex 7 and included in section 7.1.  
More details are provided in section 7.2 on the 
financing of investment costs based on OECD 
analyse. Additional detailed analysis on affordability 
was included in section 7.1.  

(5) The report should show more transparently 
where the impact is expected to be different across 
Member States. It should explain how the 
financing of the investment costs will be ensured. 
In this context, it should be more explicit about the 
expected use of EU funding to support the 
measures envisaged. It should also be more 
explicit about possible affordability issues for low-
income households and whether this poses any 
risk for implementation. 
(6) The analysis should report more systematically 
on the different views expressed by the consulted 
stakeholders. 
(7) The report should specify when the initiative 
will be evaluated, and how success will be 
measured. 
Some more technical comments have been sent 
directly to the author DG. 
Table A.1.1: RSB comments and how comments have been addressed  

More details on stakeholder point of views were 
extracted from the consultation process and from the 
Evaluation to the main text. 
Section 8 and Annex 10 were completed to better 
explain when evaluations would be undertaken and 
what success indicators will be used. 
All suggestions were taken on board. 

4.  EVIDENCE, SOURCES AND QUALITY 

Besides  the  stakeholder  consultation,  the  following  main  sources  of  information  were 
used to build this impact assessment: 

1. Models developed by the JRC: The JRC has developed for several years’ models on 
water quality and quantity in the EU. These models were adapted to the policy questions 
related to the impact assessment and to the review of the Directive. They were also used 
in the context of the REFIT Evaluation of the Directive.  

2.  Consultation  of  ad  hoc  experts:  under  the  co-lead  of  JRC  and  DG  ENV,  a  small 
consortium  of  experts  were  consulted  on  specific  policy  questions.    For  each  issue,  a 
report was prepared and used directly in the IA or to improve the JRC model. All reports 
are annexed to this IA (see Annex 7). In particular, the JRC cooperated with experts to 
assess which micro-pollutants are the most typical  to  be found in  wastewater  and what 
treatment  technologies  exist  to  deal  with  these  micro-pollutants.  In  addition,  individual 
experts  provided  input  through  the  drafting  of  short  analytical  peer-reviewed  studies, 
financed  under  an  administrative  agreement  with  the  JRC  on  the  following  topics: 
individual  and  other  appropriate  systems,  antimicrobial  resistance,  combined  sewer 
overflows and urban runoff, nutrients, micro-plastics, and greenhouse gas emissions from 
the wastewater sector.  

3.  Support  from  the  Organisation  for  Economic  Cooperation  and  Development 
(OECD): DG ENV cooperated with the OECD to develop a benefit methodology for the 
UWWTD  IA.  This  was  done,  among  others,  to  address  methodological  shortcomings 
uncovered  in  the  Evaluation  of  the  UWWTD.  Furthermore,  the  OECD  re-assessed  the 

83   

 
 
 
 
investment gap to reach full compliance with the current UWWTD. OECD also provided 
analysis of the issues related to transparency and governance.   

4.  In  depth  consultation  of  the  Member  States:  in  order  to  establish  a  solid  baseline 
scenario but also to gather evidence on the best practices in place in the Member States, a 
specific  consultation  of  each  Member  State  was  organised  in  2020.  For  each  country  a 
fiche  was  pre  filled  with  the  hypothesis  JRC  intended  to  use  in  the  context  of  the 
modelling. Each fiche was about 50 pages long and contained tentative  assumptions on 
how far advance the Member State is  in  implementing policy measures that go beyond 
the current Directive. Member States had a 4-6-week period of time to comment on the 
information and the assumptions. The main assumptions taken per MS are summarised in 
Annex 5.     

5.  To  support  the  analysis  of  the  different  options,  the  European  Commission  awarded 
two support contracts to external consultants:  

 

for  the  general  Impact  Assessment  Support  Study,  a  consortium  of  consultants 
comprised: Wood E&IS GmbH (consortium lead) with Trinomics, Ricardo, IMDEA, 
ELLE and Tyrsky.  

  another  consortium  led  by  BioInnovation  in  association  with  RDC  Environment, 
AirQuality  Consultants,  VVA  Economics  &  Policy  and  CETAQUA  Water 
Technology  Center  assessed  the  feasibility  of  an  Extended  Producer  Responsibility 
System for micro-pollutants.  

Further evidence was compiled from the  Evaluation report of the UWWTD (2019), the 
OECD  water  investment  needs  study  (2020)  and  a  vast  variety  of  background 
information  submitted  by  stakeholders  over  the  course  of  the  IA.    Further  information 
regarding the evidence used is included in each section via footnotes as well as in Annex 
10  (references).  In  addition,  extensive  consultation  of  stakeholders  was  carried  out,  as 
detailed  in  Annex  2.  The  data  used  in  this  IA  are  those  that  were  available  when  the 
calculation model was developed (data from 2016). Data for 2018 were in the meantime 
available. The difference between the 2016  and the 2018 data set  is  minimal  (less  than 
0,5% of distance to target) due notably to the long time period needed for the investments 
to produce their effects. These differences have no influence on the conclusions related to 
the main and the preferred options detailed in this impact assessment.  

84   

 
 
 
 
 
ANNEX 2: STAKEHOLDER CONSULTATION (SYNOPSIS REPORT) 

The impact  assessment accompanying the revision of the  Urban Wastewater Treatment 
Directive  was  subject  to  a  thorough  consultation  process  that  included  a  variety  of 
different  consultation  activities,  as  set  out  in  the  Consultation  Strategy.  The  methods 
selected  for  consulting  stakeholders  consisted  of  semi-structured  interviews  (speed 
dates), interactive workshops with the option to send additional feedback after workshop, 
a  broad  online  public  consultation  (OPC)  to  reach  a  large  range  of  stakeholders  on  a 
variety of topics as well as written consultation on factual information and assumptions 
for  modelling.  A  final  stakeholder  conference  was  held  to  have  their  views  on  the 
different  policy  options  proposed  by  the  Commission  and  was  divided  into  three  main 
sessions.  

1. CONSULTATION STRATEGY & ACTIVITIES 

The  consultation  strategy  identified  groups  of  stakeholders  and  consultation  activities. 
The  consultation  strategy  was  developed  at  the  start  of  the  study  by  DG  Environment, 
assisted by its consultants.44 The strategy identified groups of stakeholders, consultation 
activities and mapped these as presented below. Table A2.1 below presents the different 
groups consulted and the consultation approaches:  

Stakeholder groups 

EU Member States and their 
public authorities 

Industrial/economic actors, 
including small and 
medium sized enterprises, 
represented through EU 
level association. 
Non-Governmental 
Organisations 

International organisations 

Academia, research and 
innovation 

Citizens 

Open public 
consultation 

Member State 
overviews 

Interviews 

Stakeholder 
workshops 

Final 
conference 

Consultation activity 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

x 

Table A2.1 below presents the overview of the stakeholder activities:   

Consultation  
activity 

29/01/2020-30/01/2020 
Making water fit for life – 
LIFE and the Urban Waste-
Water Treatment Directive  

Attending 
 Stakeholders 
Over 100 participants: 
technical experts from 53 EU 
LIFE and 7 H2020 projects 
representing 14 member 
states. 

Main discussion points and results  

Key discussions outcomes included: 1) Circular economy 
aspects need to be included in the new UWWTD. 
Harmonised EU Regulatory Framework is required to 
facilitate the secondary use of raw materials. Particular focus 
should be on energy and nutrient recovery. 2) Contaminants 
of emerging concern are generated through pharmaceuticals 
and other products, which therefore require a shared 
(extended) responsibility to be applied. Raising awareness to 
change attitudes and behaviour in society is key. But lack of 
financial resources present barriers to develop technologies. 

44 European Commission (2021) UWWTD Consultation strategy 

85   

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                           
3) SWOs ad CSO need more precise and more ambitious 
regulation. Potential solutions included NBS and green 
infrastructure, and sustainable drainage systems. 4) 
Legislation/ regulation needs to drive the development of 
improved technologies, especially in relation to online, real-
time monitoring. 
General support for the revision of the Directive 
Important topics to consider in the revision: micro-pollutants, 
energy consumption, sludge and water reuse management, 
address SWOs, climate neutrality and coherence with other 
EU legislation.  

Overall general agreement on the topics identified for the 
revision. New topics: access to sanitation and water reuse. 
Divergent views between those preferring a risk-based 
approach compared to those in favour or stricter standards.  
Audits for energy and climate neutrality generally supported. 

Informal meeting to present preliminary ideas for policy 
measures to the MS providing room for feedback (orally and 
in written format). 
Though problems with remaining pollution are 
acknowledged, MS are cautious regarding the cost and 
benefits of addressing them.  
Support regarding better management of energy use.  
There is room for improvement regarding nutrient 
management (min. targets and definition of sensitive areas) 
under the UWWTD 
Few MS already address micro-pollutants in wastewater, 
control at source, monitoring and addressing micro-
pollutants in hotspots is needed. EPR could be a solution to 
deal with additional costs. 
Different methods to monitor and calculate GHG emissions 
for the wastewater sector were discussed. 

MS appreciated focus on simplification of reporting. QA/QC 
is a major burden.  
Art. 15: some MS already use datasets that can be filled by 
operators directly.  
Art. 16: general agreements that this Article is outdated and 
information should be more tailored to what is location-
specifically interesting.  
Art. 17: agreement that this Article needs to be simplified 
with a focus on access to EU funding. 
Key discussions outcomes included: 1) Participants indicated 
the need for more data to be collected on WWTP processes 
for better quantification of energy consumption/production. 
2) Energy auditing and the tracking of energy use was 
portrayed as a key area to fill data gaps. 3) Participants were 
concerned about GHG emission targets since the data gap to 
set a well-informed baseline was missing. 
The OPC consisted of introductory questions related to 
respondent profiles, followed by a questionnaire divided into 
two parts: the general questionnaire and the targeted expert 
survey. The OPC included questions to examine the general 
public’s perception of the success and needed improvements 
of the UWWTD, as well as an expert section that targeted 
those with more expertise to elaborate on their views 
regarding specific measures to be taken in the impact 
assessment of the directive. The survey was made available 
in all EU languages on the Have Your Say Portal and 
uploaded to the EU Survey tool. 
Key discussions outcomes included: 1) to identify all 
uncertainties and be transparent about these, 2) synergies and 

21/07/2020-08/09/2020 
Roadmap feedback 

14-16/10/2020 
Speed dates with selected 
stakeholders 

22/10/2020 
UWWTD Member States 
expert meeting. 

26-27/11/2020 
Joint DE/EC UWWTD 
Revision conference on 
nutrients and micro-
pollutants. 

19/02/2021 
Expert workshop on a 
computational scheme for 
GHG from wastewater.  
23-24/03/2021 
Joint workshop with the EEA 
on reporting. 11th reporting 
cycle, 12th reporting cycle, 
Treatment Plant under the E-
PRTR and the Industrial 
Emissions Portal, 
streamlining of monitoring 
and reporting. 
20-21/04/2021 
Joint workshop on sludge and 
urban wastewater in light of 
climate change and the 
circular economy. 

28/04/2021-21/07/2021 
Online Public Consultation 
(12 weeks)  

57 replies from business 
associations (35%), NGOs 
(14%), individual companies 
(25%), public authorities 
(14%), EU citizen (9%) and 
research institutes (2%) from 
across the EU. 
10 stakeholders representing 
the wastewater sector or 
related sector and interests 
(e.g. env. NGOs). 
All stakeholders received a 
background document with 
draft policy ideas in advance. 
100 participants from all EU 
MS.  
A background document with 
draft policy ideas was 
circulated in advance. 

About 200 participants from 
Member States and 
stakeholder associations.  
A background document was 
circulated in advance of the 
conference. 

About 20 experts.  
A draft computational scheme 
was circulated in advance 
among the experts. 
127 participants from all 27 
Member States and observers 
from the UWWTD Expert 
Group.  
A background document was 
circulated in advance.  

Day one: 323 participants 
from 15 Member States. 
Day two: 290 participants 
from 16 Member States.  
A background document was 
circulated in advance of the 
workshop. 
A total of 285 responses and 
57 position papers were 
received from stakeholders in 
22 Member States. 

04/05/2021 
Cost and benefits workshop. 

80 participants from all 
Member States and 

86   

 
 
 
 
stakeholder associations. 

29/04-21/05/2021 
Member State overviews and 
targeted questionnaires. 

25 out of 27 Member States 
replied to the written 
consultation. 

22/06/2021 
Workshop in approaches for 
integrated management of 
collecting systems in the 
revision of the UWWTD. 

177 participants from 27 MS  
and 6 from third countries, 
stakeholder associations and 
local authorities. 

August 2021 
Interviews 

26/10/2021 
Stakeholder conference 

A few selected EU-level 
stakeholder associations were 
contacted for further 
information on specific topics. 

312 participants from 226 
organisations and all 27 MS. 
There were a total of 9 non-
EU participants from Iceland, 
Morocco, Norway, Scotland 
and Serbia. 

trade-offs between policy measures should be considered and 
3) a revised Directive will lead to additional cost while some 
MS are still “catching up” with the current Directive. For 
these MS it is expected that the revised Directive will lead to 
efficiencies in implementation. 
For all Member States detailed factsheets on topics related to 
urban wastewater management were prepared to reflect the 
current situation in the country in particular identifying 
where the current practices are going beyond the UWWTD 
requirements. All factsheets included tailored assumptions 
for the Member States that would be used for the modelling 
of the baseline. Member States were asked to validate and 
add to the information provided. 
Key discussions outcomes included: 1) NBS and green 
infrastructure need more knowledge sharing and financial 
support for further implementation, 2) Targets for SWOs and 
urban runoff need to be set at EU level while still allowing 
MS control to account for local conditions, 3) Collection 
systems need to deliver sustainable solutions to urban 
environments while maintaining/achieving good/high status 
of water bodies, 4) Modelling and regular water quality 
monitoring systems may be costly and time intensive but 
provide necessary information for developing collection 
systems. 
A series of targeted interviews was organised in the final 
stage of the data collection. A list of questions was sent to 
them ahead of the interviews which were then discussed. 
Interviews focused on remaining gaps including costs and 
benefits of the various options considered.  
Key discussions outcomes included: 1) Industrial pollution 
needs to be addressed up-stream using the polluter pays 
principle, 2) NBS and green infrastructure to be considered 
in addressing SWOs and IAS, 3) UWWTD should be aligned 
with existing legislation (e.g. WFD), 4) facilities must 
contribute to climate-change mitigation (energy efficiency 
audits were welcomed as a first approach), 5) improving 
resource recovery and water reuse, 6) apply risk-based 
approaches for advanced treatments, and 7) participants 
recognised that interventions at different levels of 
governance are necessary (proportionate and require clarity 
on the roles of the stakeholders). 

87   

 
 
 
 
 
 
 
2. STAKEHOLDER GROUP 

Overall,  the  consultation  activities  have  been  successful  in  reaching  the  identified 
stakeholder  groups  as  defined  in  the  consultation  strategy.  All  Member  States  and  the 
vast majority of industrial/economic actors were represented. For citizens, the OPC was 
the primary approach for engagement. While citizens were the second highest  group of 
respondents in the OPC, the number was overall low when considering it in the context 
of the entire project.   

A wide range of stakeholders groups were involved throughout the activities, for example 
the split  of groups involved in  the OPC is  presented in  the figures below.  Figure A2.1 
below shows the share of the 228 participants by stakeholder type for the OPC. 

Although  285  stakeholders  participated  in  the  OPC,  only  228  of  those  answered  the 
question  about  the  stakeholder  type  they  represented.  In  the  OPC,  stakeholders  were 
asked to indicate the sectors which they represented (by selecting three subjects that were 
relevant to the representation of their organisation).  

Figure A2.2 below illustrates the representation of different sectors in the OPC: 

Stakeholders  from  all  EU  Member  States  and  third  countries  were  involved  in  the 
consultation  process.  For  example,  the  final  conference  saw  participants  from  226 
organisations across all 27 Member States. In addition, there were a total of nine non-EU 
participants representing Iceland, Morocco, Norway, Scotland and Serbia.  

88   

21%; 61 19%; 55 17%; 48 15%; 42 11%; 30 8%; 23 5%; 15 2%; 6 1%; 2 1%; 2 0%; 1  - 10 20 30 40 50 60 70Company/business organisationEU citizenPublic authorityBusiness associationNon-governmental organisation (NGO)OtherAcademic/research institutionEnvironmental organisationTrade unionNon-EU citizenConsumer organisation23%, 143 23%, 139 12%, 75 11%, 69 6%, 34 5%, 33 3%, 18 2%, 14 3%, 16 3%, 16 2%, 15 050100150200250Waste water treatment sectorWater industry and/or…Public sectorBiodiversity and/or environmentNon-governmental organisationScientific researchEnergyUrban planning and developmentChemical industryClimate PolicyOther 
 
 
 
 
 
3. METHODOLOGY AND TOOLS USED TO PROCESS THE DATA 

All  feedback  submitted  through  different  consultation  activities  was  collated  and  taken 
into account in the analysis presented in the impact assessment. Questionnaire responses 
from  the  OPC  were  obtained  from  the  European  Commission  Survey  system.  For  the 
final OPC data download, no significant update of formatting/data structure was required. 
The steps followed were: the raw data was imported and cleaned in an Excel template; no 
campaigns  were  identified,  but  small  series  of  duplicated  responses  were  noted.  There 
were three sets of duplicated responses which were not removed but it has been ensured 
duplicates  are  not  double-counted  the  statements  in  the  open-response  analysis.  It  is 
considered that these duplicates have no impact on the overall results.  

Graphics presenting the details of the responses, distinguishing stakeholders’ categories 
and Member States were created via Excel. Respondents had the option of elaborating on 
their  answers  in  open  text  fields  or  responding  to  stand-alone  open-ended  questions. 
Responses in  all languages were analysed after having been translated to  English using 
machine  translation.  Survey  data  was  then  analysed  and  coded.  The  aim  of  the  coding 
exercise  was  to  identify  the  keywords  and  themes  mentioned  by  respondents  and  then 
attribute these as established “codes” for which a consensus can be built and counted. For 
instance, if one respondent mentions a need for more transparency, “more transparency” 
can be coded and then used to count further responses that communicated the same need.  

Finally,  any  attachments,  links,  or  other  materials  submitted  by  stakeholders  were 
analysed  and  incorporated  throughout.  Qualitative  and  quantitative  data  obtained  from 
workshops,  interviews  and  the  conference  were  summarised  in  respective  reports 
(available  on  CIRCABC)  and  included  into  the  analysis  of  individual  measures  in  the 
impact  assessment.  Feedback  from  consultation  activities  has  been  integrated  into  the 
assessment of policy measures per area of improvement, informing recommendations for 
each  area.  The  MS  overviews  have  been  integrated  into  the  final  report  through  a 
horizontal analysis as well as informing detailed assessment of policy measures per area 
of improvement.   

Overall, the evidence collected throughout the consultation has been compared with other 
evidence gathered, namely with results of individual consultations as well as the results 
of  the  literature  review,  modelling  and  data  analysis.  This  triangulation  of  several 
research methods helped to identify whether there were any major divergences between 
different sources of evidence.   

4. OPC – GENERAL VIEW 

The  OPC  was  divided  into  five  sections.  After  some  initial  questions  regarding  the 
profile  of  respondents,  sections  2-3  were  addressed  to  all  respondents  and  covered 
respondents’  understanding  of  the  UWWTD,  their  views  on  the  problems  relating  to 
wastewater  pollution,  and  how  to  best  address  water  pollution  through  wastewater 
treatment processes. Section 4 was targeted at expert respondents and included more in-
depth questions on specific measures to address in the revision of the Directive. Finally, 
respondents could share additional relevant materials/publications and/or information in 
section 5. As most of the questions were not  mandatory, the total  number of responses 
for each question varies throughout the report. 

A  high  number  of  respondents  agreed  that  wastewater  was  correctly  treated  before 
discharge in their country of residence, particularly respondents from Germany (n=64/77, 

89   

 
 
 
 
83%)  and  Austria  (n=7/8,  87%)  who  overall  showed  the  most  agreement.  When  asked 
whether  urban  wastewater  was  an  increasing  source  of  pollution,  stakeholders  mostly 
disagreed  with  that  statement,  with  59%  (n=159)  disagreeing  (particularly  respondents 
from  Germany,  Austria,  Spain,  and  Sweden  with  75%,  100%,  79%,  and  84%  of 
respondents disagreeing, respectively).  

When asked about the risk perception of pollution from untreated wastewater, almost all 
risks were rated by more than half of respondents (n=152), as a significant concern. The 
topic ranked of the highest importance to be addressed in the upcoming revision was the 
improved implementation of the polluter pays principle; where 68% of respondents felt 
that this was a very important topic. On the importance of monitoring and removal of 
contaminants, there was consensus among respondents that all contaminants listed 
required stronger efforts to be addressed. Respondents also indicated that there was a 
need for receiving more information (e.g. informing the public). 

Open text  answer analysis  showed that businesses/companies and the public authorities 
were  mainly  concerned  with  the  details  of  implementing  proposed  measures  and  the 
potential  additional  cost  burdens.  Lastly,  the  OPC  showed  all  stakeholder  groups’ 
support  for  measures  related  to  access  to  sanitation,  access  to  information  and  more 
coherence and alignment of the UWWTD with other policies. 

Two topics that stood out as particularly important to experts were the introduction of an 
extended  producer  responsibility  (EPR)  scheme  to  further  implement  the  polluter  pays 
principle and the need to better tackle pollution at-source. However, businesses were the 
most  critical  about  the  feasibility  of  the  EPR,  where  all  votes  for  ‘not  at  all’  effective 
(n=16, 7%) came from this stakeholder group.  

90   

 
 
 
 
 
 
5.  STAKEHOLDERS’ VIEWS ON THE DIFFERENT AREAS45 

5.1 Storm water overflows and urban runoff 

Issues relating to the improved management of SWO and urban runoff were considered 
of high importance to all stakeholders.  

During the workshop, strong support from participants for the increased use of Integrated 
Management Plans was identified, whilst support for target values for SWOs and urban 
runoff received the lowest support from participants. Similarly, the OPC results indicated 
that a strategic integrated planning approach for management and prevention was highly 
supported. OPC respondents were also strongly supportive of NBS playing an increased 
role in managing urban wastewater, with 71% of respondents (n=185) rating this as either 
very  important  (5)  or  important  (4).  Expert  stakeholders  were  asked  about  the 
appropriateness  of  various  measures  to  minimise  pollution  through  SWOs  and  urban 
runoff.  The  most  positive  response  from  all  respondents  was  for  the  statement  that  a 
combination of measures is required to achieve the needed results. Mandatory reporting 
of  overflows  was  considered  the  least  appropriate  measure,  particularly  by  public 
authorities and businesses (average scores 2.9 and 3.2, respectively). 

OPC  Targeted  consultation:  How  appropriate  are  the  following  proposed  measures  for 
minimising pollution through storm water overflows and urban run-off? Please rate on a 
scale of 1 to 5 (1 = not at all; 5 = very appropriate). (n= 260). 

45 For more details, please refer to Appendix F Views of the stakeholders by area of improvement from the 
WOOD report – report 1 in Annex 10 

91   

Public authorities; 2,9 Public authorities; 3,2 Public authorities; 3,1 Public authorities; 3,2 Public authorities; 3,5 Public authorities; 3,8 Public authorities; 3,6 Public authorities; 4,1 NGOs; 4,0 NGOs; 4,2 NGOs; 4,2 NGOs; 4,5 NGOs; 4,4 NGOs; 4,6 NGOs; 4,7 NGOs; 5,0 Citizens; 3,8 Citizens; 3,8 Citizens; 3,8 Citizens; 4,1 Citizens; 3,9 Citizens; 4,3 Citizens; 4,2 Citizens; 4,4 Businesses; 3,2 Businesses; 3,4 Businesses; 3,4 Businesses; 3,6 Businesses; 4,0 Businesses; 4,0 Businesses; 4,3 Businesses; 4,5 Academia; 4,2 Academia; 4,3 Academia; 4,4 Academia; 4,3 Academia; 4,2 Academia; 4,3 Academia; 4,4 Academia; 4,7 All respondents; 3,4 All respondents; 3,6 All respondents; 3,6 All respondents; 3,8 All respondents; 3,9 All respondents; 4,1 All respondents; 4,2 All respondents; 4,5 Introducing mandatory reporting for frequency and volumes ofoverflowsIntroducing continuous monitoring to measure frequency,volumes and pollution in the network to improve managementEstablishing EU targets regarding the management of stormwater overflows and urban run-off (e.g. dilution rates, rainwater treatment capacity, rain water storage capacity andminimum treatment for run-off)Providing EU guidance on strategies for preventing, reducing andmanaging pollution from storm water overflows and urban run-offApplying a risk-based approach to deal with storm wateroverflows and urban run-off in line with the Water FrameworkDirective (WFD) objectivesRequiring the use of nature-based solutions to reduce theamount of clean water to be collected in public systems (e.g.through natural water retention measures, green urbanisation)Establishing an obligation for agglomerations to adopt astrategic planning approach to the management and preventionof storm water overflows and urban run-off (e.g. develop anintegrated management plan for collecting systems)To what extent do you agee with this statement: 'To beeffective, action must combine several types of measures' 
 
 
 
 
 
 
                                                           
5.2 Smaller agglomerations 

The  need  for  several  types  of  measures  to  address  the  issue  was  highlighted  by 
stakeholders.  Results  from  the  OPC  show  that  introducing  a  risk-based  approach  for 
urban  wastewater  management  in  agglomerations  below  a  certain  size  (requiring  more 
treatment  where  their  discharges  can  cause  problems)  was  rated  the  most  appropriate 
individual measure across all stakeholder groups. Respondents noted that the risk-based 
approach  was  already  covered  under  the  WFD.  Redefining  agglomerations  scored  an 
appropriateness score of 3.6 (1-low and 5-high), however three respondents highlighted 
that  they  were  not  able  to  propose  a  better  definition.  Suggestions  made  included 
considering size and distance to sewer system. It was highlighted that there is a need to 
improve  the  centralisation  and  the  connection  rates  of  smaller  agglomerations  to  larger 
treatment plants in order to reduce pollution impacts. 

5.3 IAS 

Overall,  a  flexible  system,  was  favoured  and  stakeholders  also  indicated  that  guidance 
was  needed  on  IAS  technologies,  registration,  monitoring,  and  inspections.  From  the 
OPC, the option to require agglomerations to report to the EC if an IAS is used to collect 
more than a set amount of the load was generally perceived as inappropriate to address 
the  problem.  Academics  were  most  supportive  of  reviewing  the  EU-wide  standards  for 
IAS  (4.8)  and  generally  felt  that  the  measures  presented  were  appropriate.  Businesses 
were  particularly  in  favour  of  ensuring  connection  to  public  sewer  systems  (4.1), 
providing guidance on IAS technologies (4.0), and reviewing the definition of IAS (4.0).  

Citizens  were  generally  supportive  of  the  measures  presented  but  showed  a  lower 
average  response  for  reporting  to  the  EC  (3.4)  and  requiring  countries  to  keep  an  IAS 
registry. NGOs were particularly critical on requiring agglomerations to report to the EC 
(3.0). Public authorities, on the other hand, only showed an average positive response for 
ensuring connection to the public sewer system (4.0). Measures relating to a risk-based 
approach, consumer awareness campaigns, keeping an IAS registry, and limiting IAS use 
generally  had  more  support  from  academia  and  citizens  than  from  other  stakeholder 
groups.  One  NGO  respondent  also  noted  the  difference  that  consumer  awareness  can 
create and how education of the general public on these issues can widely encourage an 
EU-wide change in behaviour over time.  Overall, there was quite a varied interest and 
response between stakeholder groups, but also within the different groups themselves. 

Several  of  the  position  papers  submitted  addressed  the  topic  of  IAS.  EurEau  supported 
the  use  of  a  database  to  record  the  use  of  IAS  under  the  responsibility  of  the  local 
authority.  EurEau  and  AquaPublica  both  raised  the  fact  that  some  flexibility  should  be 
kept so that the cost of connection, and the associated emissions with building networks 
are considered. 

5.4 Sensitive areas 

Overall,  stricter  N/P  emission  requirements  were  supported  by  stakeholders.  While  an 
obligation  for  additional  treatment  where  there  is  a  bathing  site,  shellfish  water  or  a 
drinking water catchment downstream (and abandoning criterion b and c in Annex II of 
the Directive) was widely supported, a more general stringent standard for N/P treatment 
for all large UWWTPs was less popular with OPC respondents. Moreover, with regard to 
sensitive areas, the most highly rated measures was providing EU-level guidance (score 
4.2/5). Measure 1 on improving the ways ‘sensitive areas’ are designated by requiring the 

92   

 
 
 
 
same methodology and criteria to be used and aligning them with the Nitrates Directive 
and  the  WFD  (score  4.1/5).  Also  the  less  rated  one  abandon  the  possibility  for  MS  to 
designate less ‘sensitive areas’.  

5.5 Micro-pollutants 

Across all stakeholders’  categories, increasing consumer awareness  on releasing micro-
pollutants and on safely using and disposing products was a widely supported approach 
to  the  issue.  Stakeholders  generally  supported  the  idea  that  micro-pollutants  are  the 
responsibility  of  manufacturers  and  producers  and  the  concept  of  source  control  was 
widely supported. From the OPC, on average, all contaminants were ranked with similar 
importance. Respondents also commented on the need to prevent pollution at source and 
the greater need for the polluter pays principle to be implemented. The results of the OPC 
highlight  the  general  desire  from  respondents  for  the  UWWTD  to  increase  monitoring 
and  improve  the  removal  of  contaminants  in  wastewater.  The  responses  show  that 
predominantly  respondents  felt  that  manufacturers  and  producers  were  responsible  for 
addressing pollution of most contaminants.  

The exception is for urban runoff, where 69% of respondents felt the responsibility lies 
with  the municipalities (n=71).  Industrial  wastewater  contaminants had the highest  rate 
of agreement with 91% (n=97) of respondents indicating that this is the responsibility of 
manufacturers and producers, which further reflects earlier results on the importance of 
tracking industrial contaminants and the importance of the polluter pays principle.  

To address micro-pollutants, setting an obligation for EPR to fund upgrades of UWWTPs 
had  by  far  the  most  positive  response  across  all  stakeholder  groups  (4.3)  whereas  the 
introduction  of  a  risk-based  approach  (3.7)  and  requiring  larger  UWWTPs  to  remove 
micro-pollutants  based  on  EU-set  performance  indicators  (3.2)  ranked  lowest.  While 
academics, citizens, and NGOs generally felt measures were appropriate, businesses felt 
particularly  negative  towards  requiring  larger  UWWTPs  to  remove  micro-pollutants 
based on EU-set performance indicators. Despite there being a lower overall ranking for 
the  risk-based  approach,  a  number  of  open  responses  highlighted  their  support  for 
bioassays  and  their  suitability  to  identify  hotspots  or  effluent  toxicity.  However,  all 
respondents noted that there are some challenges in the application of bioassays that need 
to  be  taken  into  account  when  identifying  the  correct  bioassay  to  use  under  specific 
circumstances  (n=4).  Regarding  the  position  papers,  it  was  commonly  mentioned  that 
substances of emerging concern should be better considered under the revised Directive 
text  (n=3)  and  that  the  list  of  substances  covered  should  be  revised  (n=5)  and, 
furthermore, that this list should be an open and/or live list that can be updated when new 
substances of concern emerge (n=2).  

93   

 
 
 
 
 
 
OPC  Targeted  consultation:  How  appropriate  are  the  following  proposed  measures  for 
addressing micro-pollutants under the UWWTD? Please rate on a scale of 1 to 5 (n=258) 

5.6 Industrial Emissions  

Views  from  stakeholders  confirmed  that  there  is  a  need  for  action  to  enhance  coherent 
legislative  requirements,  as  identified  in  the  recent  UWWTD  evaluation.  This  would 
include  alignment  of  monitoring  and  reporting  requirements  under  different  sets  of 
legislation. A generalised comment across all stakeholders was the need for coherence of 
the UWWTD with other Directives, especially with the IED. 

From  the  OPC,  a  very  positive  response  across  all  stakeholders  was  recorded  for  the 
is 
industrial 
measure  requiring  pre-treatment  at 
discharged into UWWTP. Regarding the type of contaminants that should be prioritised 
for  removal,  on  average  all  contaminants  were  ranked  with  similar  importance. 
Endocrine  disruptors  and  other  pollutants  from  industrial  installations  had  the  highest 
score, closely followed by pharmaceutical residues, excess nutrients, and pesticides.  

installations  before  wastewater 

Micro-plastics as well as nutrients and pharmaceuticals had a wider spread of responses 
resulting  in  the  lowest  average  rate  of  importance.  Overall,  respondents  felt  that  that 
stepping  up  monitoring  and  removal  of  all  listed  contaminants  was  at  least  somewhat 
important.  Industrial  wastewater  contaminants  were  considered  for  91%  of  respondents 
as  being  the  responsibility  of  manufacturers  and  producers,  which  further  reflects  the 
importance of tracking industrial contaminants, and the importance of the polluter pays 
principle.  

Targeted interviews drew several  conclusions regarding industrial discharges including: 
the need for policy coordination, especially  with the WFD, but also with the IED, SSD 
and  Nitrates  Directive;  mixed  views  on  the  added  value  of  IED/BREF  process  for 
wastewaters; a need for further reflection on industrial releases in the urban networks; a 
short-list  of  selected  indicators  of  groups  of  substances  that  should  be  monitored  in 
treated wastewater and trigger more targeted source control if thresholds are reached; and 

94   

Public authorities; 3,4 Public authorities; 3,4 Public authorities; 3,6 Public authorities; 4,2 Public authorities; 4,3 NGOs; 4,1 NGOs; 4,4 NGOs; 4,5 NGOs; 4,8 NGOs; 4,9 Citizens; 4,0 Citizens; 3,8 Citizens; 4,2 Citizens; 4,5 Citizens; 4,6 Businesses; 2,5 Businesses; 3,5 Businesses; 3,6 Businesses; 3,9 Businesses; 4,3 Academia; 3,8 Academia; 3,9 Academia; 4,1 Academia; 4,5 Academia; 4,8 All respondents; 3,2 All respondents; 3,7 All respondents; 3,9 All respondents; 4,3 All respondents; 4,5 Requiring large UWWTPs to remove micropollutants based onseveral EU-set performance indicator substances to reducemicropollutants by X% (X to be defined based on analysis). Theperformance indicator substance indicates whether thetreatment has workedIntroducing a risk-based approach using bioassays to identifyhotspots requiring additional treatment upgrades based onchemical substances present in the waterAdopting EU guidance on good practices focusing on, amongother things, micropollutants, antimicrobial resistance, etc.Set an obligation for Extended Producer Responsibility Scheme tofund the upgrades of UWWTPs to improve treatment and toincentivise research and development into more sustainablechemicals upstreamTo what extent do you agree with this statement: ‘To be effective, action must combine several types of measures’ 
 
 
 
 
a  general  principle  in  the  Directive  in  relation  to  industrial  releases  could  be  useful 
although it is acknowledged that it is difficult to enforce because of resources constraints. 

5.7 Energy efficiency, generation and climate neutrality 

Stakeholders  indicated  that  more  data  is  required  on  WWTP  processes  to  enable  better 
quantification  of  energy  consumption/production.  Energy  auditing  and  the  tracking  of 
energy use were highlighted as being key activities which could be used to fill these data 
gaps. 

The OPC results as well as inputs received during the specific workshops showed that all 
stakeholder categories  broadly support the  generalisation of energy audits. There was a 
general recognition on the necessity to better understand and monitor energy use of the 
treatment plants so that measures can be taken to reduce energy use and where possible 
produce  energy.  Citizens,  NGOs  and  to  a  lesser  extent  academia  were  supportive  on 
introducing  energy  related  targets  while  mixed  views  were  expressed  by  public 
authorities  and  business.  Some  representatives  from  MS  and  business  pointed  out  that 
these targets should be introduced for large UWWTPs only, and, despite the importance 
of the 2050 energy neutrality targets, these should not hamper the primary objectives of 
UWWTPs; wastewater treatment. Other representative of business were in favour of both 
climate and energy neutrality targets. Most advanced MS were clearly supporting an EU 
wide target similar to their own target.  

In the targeted consultation component of the OPC, proposed measures to address energy 
use  and  emissions  were  generally  not  as  highly  rated  as  other  measures  in  previous 
sections. On average, the highest rated measure was related to introducing an obligatory 
energy  audit  in  larger  plants  (3.8),  which  was  rated  highest  by  academia,  citizens  and 
NGOs. In terms of stakeholder response patterns, academics indicated the most support 
for the measure relating to setting energy use reduction targets based on UWWTP sizes. 
This  was,  on  the  other  hand,  businesses  least  rated  option,  with  a  generally  negative 
perception.  Overall,  none  of  the  stakeholder  groups  felt  particularly  positive  about 
introducing  energy  efficiency  targets  at  a  national  level  (average  3.0)  –  in  particular, 
public authorities did not seem supportive of the measures (2.6). 

Academics  noted  in  the  open  text  questions  for  suggestions  that  energy  efficiency  and 
regulation  of  emissions  must  consider  other  additional  emissions  as  a  consequence,  for 
example nitrous oxide and nitrogen dioxide (n=2). Public authorities generally expressed 
their support for the implementation of energy audits and improved energy management 
(n=4), however they also expressed that the best possible purification of wastewater must 
not  be  lost  from  sight  when  trying  to  implement  rigid  energy  efficiency  classes  (n=1). 
The  respondents  also  noted  that  energy  efficiency  and  management  should  be  strictly 
addressed  during  the  design  and  renovation  phases  of  plants  and  suggested  that  the 
Directive’s  wording  should  not  go  beyond  suggesting  energy  efficiency  be  considered 
during these steps (n=2).  

Business respondents showed support in particular for energy audits (n=4) but expressed 
concerns regarding target setting. Similar to Public authorities, Businesses expressed the 
importance  of  efficient  cleaning  producers  and  set  it  as  a  higher  priority  than  energy 
efficiency, which thus spoke against setting firm targets (n=4).  

95   

 
 
 
 
 
During workshop on wastewater and sludge, the overall feedback of the participants was 
that  it  should  be  up  to  MS  to  decide  which  interventions  to  apply  to  which  treatment 
plants to achieve the best efficiency results based on local data from operators, treatment 
stages  and  applied  technology.  The  challenge  of  setting  a  target  across  such  local 
variability without proper baseline remains too significant in absence of energy audits.  

In  relation  to  GHG  emissions  including  methane,  overall  views  from  stakeholders 
confirm  that  there  is  a  need  to  better  understand  the  baseline  of  GHG  emissions 
generated by UWWTPs in the EU. On the OPC results, stakeholders appeared to be more 
interested  in  energy  efficiency  investments  than  in  actions  to  reduce  GHG  emissions. 
This  could  stem  from  the  fact  that  many  respondents  had  previously  noted  that  GHG 
benefits  could  be  achieved  from  improvements  in  energy  efficiency.  Respondents 
generally  believe  that  benchmarking  and  specific  targets  should  only  be  set  once 
sufficient data is  collected from audits that would allow a well-informed baseline to be 
set. Respondents preferred, if required, that any limits set should be based on plant size 
and highlighted the need to go beyond the UWWTP and incorporate the sewer collection 
system and other sectors too. Similar conclusions were made during the workshops.  

OPC  targeted  consultation:  Response  to:  How  appropriate  are  the  following  proposed 
measures  for  improving  UWWTPs'  energy  use  and  emissions  intensity  to  help  achieve 
energy use reduction? Please rate on a scale of 1 to 5 (n=258). 

5.8 Circular economy 

The concept of source control, i.e. targeting substances such as micro-plastics and micro-
pollutants at source, was widely supported by stakeholders in order to improve circularity 
in  the  wastewater  treatment  sector.  Others  also  highlighted  the  need  for  tracking  and 
more  stringent  requirements  to  prevent  pollution  at  source  when  sludge  is  used  in 
agriculture. From the OPC, the most highly rated measure in relation to circular economy 
(sludge  reuse)  was  preventing  pollution  at  source  (Measure  4:  Member  States  to  adopt 
strategies  for  tracking  and  preventing  pollution  at  source,  in  particular  when  sludge  is 
reused  in  agro-industrial  activities.  Track  and  trace  of  pollution  if  sludge  reused  in 
agriculture  (consistent  for  industrial  emission  requirements  above.  (4.4/5)),  with  a  less 
preferred  option  setting  minimum  levels  for  recovery  phosphorous  and  other  resources 

96   

Public authorities; 2,6 Public authorities; 3,1 Public authorities; 3,4 Public authorities; 3,6 Public authorities; 3,8 NGOs; 3,2 NGOs; 3,7 NGOs; 4,0 NGOs; 4,2 NGOs; 4,5 Citizens; 3,3 Citizens; 3,5 Citizens; 4,0 Citizens; 4,0 Citizens; 4,2 Businesses; 3,0 Businesses; 2,6 Businesses; 3,1 Businesses; 3,6 Businesses; 4,0 Academia; 3,0 Academia; 4,3 Academia; 3,8 Academia; 4,2 Academia; 4,8 All respondents; 3,0 All respondents; 3,1 All respondents; 3,5 All respondents; 3,8 All respondents; 4,1 Setting energy use reduction targets at national level ratherthan for individual UWWTPsSetting energy use reduction targets based on UWWTP size tobe achieved gradually over timeIntroducing target values regarding UWWTPs renewable energygeneration/self-sufficiency over time (i.e. generating energythrough biogas)Requiring, at first, large (and subsequently, smaller) UWWTPsand their networks to carry out energy use audits followed byaction to reduce energy use over time (unless it is shownthrough standardised energy audits that due to local conditionsit is notTo what extent do you agree with this statement: ‘To be effective, action must combine several types of measures’ 
 
 
 
 
(Measure  2:  Setting  minimum  levels  for  recovering  phosphorous  and  other  materials, 
such as cellulose, from wastewater and sludge. All valuables in sludge (e.g. materials and 
energy)  need  to  be  recovered  and  recycled  /  Measure  1:  Setting  minimum  levels  for 
recovering  phosphorous  and  other  materials,  such  as  cellulose,  from  wastewater  and 
sludge, P recovery mandatory for large UWWTPs > 100.000 p.e. (Score: 3.6/5)). 

5.9 Monitoring and reporting  

The  concept  of  providing  EU-wide  guidelines  to  operators  on  ‘normal  operating 
conditions’  in  UWWTPs  to  support  comparability  of  monitoring  data  received  strong 
support.  Clarifying  the  requirements  on  sampling  conditions  and  sampling  frequency 
were also identified on the OPC as supporting the comparability of monitoring data. 

As  part  of  the  OPC,  the  measures  proposed  relating  to  sampling  frequency  and 
monitoring did not receive particularly high scores, with the majority scoring below 4 on 
average. Providing guidelines for normal operating conditions was generally considered 
the  most  feasible  measure  (average  4.0).  The  least  rated  option  was  to  replace  COD 
measurements with total organic carbon across all stakeholder groups (average 2.6). All 
stakeholders  rated  very  low  the  deletion  of  COD  monitoring  requirements  (2.3),  which 
reflects  their  willingness  to  maintain  the  monitoring  standard,  rather  than  removing  it 
entirely. 

Public authorities were less supportive of measures relating to additional parameters and 
increasing  sampling  frequencies.  This  is  likely  because  such  measures  would  cause 
additional  burdens  for  the  authorities.  NGOs  were  most  in  favour  of  adding  additional 
parameters. Academics and NGOs generally were supportive of more options than other 
stakeholder  groups,  rating  half  of  the  options  above  4.0.  NGOs  noted  in  particular  that 
many  of  the  substances  that  urgently  require  monitoring  (e.g  micro-pollutants)  often 
occur at low limits. The respondents noted that there is a need for establishing analytical 
methods  for  low  detection  limits  in  order  to  monitor  these  pollutants.  This  was  linked 
both  to  the  acknowledgment  of  the  water  body  condition  and,  therefore,  the  coherence 
with the WFD, as well as to decisions on water reuse, bathing sites and drinking water 
sources. A few businesses also mentioned the need for new monitoring parameters that 
should stimulate the use of innovative technology and integration with existing efforts to 
improve  monitoring  practices  such  as  the  use  of  satellite  data  (n=3).  OPC  respondents 
rated  the  use  of  EEA  data  availability  as  the  highest  option  overall,  indicating  that  the 
interest  in  providing  further  information  to  the  public  is  supported  by  all  stakeholder 
groups 

Some respondents also noted that harmonisation of data reporting is not the only factor 
making  comparisons  difficult  but  that  diversity  in  analysis  methods  and  the  related 
frequencies prevent environmental data from being effectively compared (n=3).  

Respondents also noted the importance of new reporting requirements to be aligned with 
other EU policies such as the E-PRTR (n=3). In this respect, respondents mentioned that 
identifying  chemical  classes  to  compare  across  countries  with  existing  PRTRs  and 
creating  a  global  PRTR  for  all  relevant  policies  should  be  considered.  Generally,  the 
pursuit  for  simpler  and  more  harmonised  reporting  was  supported  by  respondents  but 
there  seems  concern  regarding  the  increasing  ambitions  in  the  other  sub  areas  and  the 
possible additional reporting costs that this may cause. 

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The  conclusions  from  the  workshop  on  reporting  specifically  highlight  that  regarding 
Art. 15, some MS already use datasets that can be filled by operators directly; on Art. 16, 
there are general agreements that this Article is outdated and information should be more 
tailored  to  what  is  location-specifically  interesting,  and  finally,  on  Art.  17,  there  is  an 
agreement that this Article needs to be simplified with a focus on access to EU funding.  

5.10 Wastewater surveillance 

Recent developments have indicated that wastewater surveillance can be used as an early 
warning  signal  for  the  current  coronavirus  pandemic  and  further  viral  outbreaks  that 
could  occur  in  the  future.  These  are  aspects  that  are  not  covered  by  the  existing 
legislative  framework.  Stakeholders  preferred 
the  provision  of  guidelines  for 
collaboration between UWWTPs and health authorities compared to other measures. 

Regarding  the  OPC,  respondents  generally  felt  that  the  additional  costs  of  wastewater 
surveillance  should  be  covered  by  different  groups  /  entities,  but  health  authorities 
received the highest number of total votes (48%, n=122), followed by the general public 
(37%, n=93). When asked about measures on how to incorporate wastewater surveillance 
in  the  UWWTD,  stakeholders  preferred  the  provision  of  guidelines  for  collaboration 
between  UWWTPs  and  health  authorities,  as  well  as  establishing  EU-wide  binding 
standards  on  implementation.  Respondents  noted  that  the  characteristics  of  local 
conditions  need  to  be  taken  into  account  and,  therefore,  national  rather  than  EU-level 
targets would be more appropriate. Nonetheless, a number of respondents mentioned that 
standardization for water surveillance was important. 

5.11 Information to the public 

Stakeholders  appeared  to  widely  support  improvements  to  accessing  information  from 
UWWTPs although accessing real-time information on water quality after treatment was 
of least interest. 

Results  from  the  OPC  show  that  quality  of  rivers,  lakes,  and  seas  where  wastewater  is 
discharged and the compliance of the UWWTP with the EU, national and regional laws 
were  the  two  most  highly  yes-voted  information  subjects  at  77%  (n=  205)  and  72% 
(n=192),  respectively.  The  least  interesting  information  appeared  to  be  real-time 
information  on  water  quality  after  treatment  as  well  as  sources  for  funding,  which  had 
more respondents voting no or did not know/no opinion than yes.  

In the targeted part of the questionnaire, stakeholders were of the opinion that regardless 
of  what  measures  are  to  be  taken,  there  is  a  strong  need  to  improve  the  level  of 
communication  and  information  provided  to  the  public.    The  highest  support  among 
stakeholders was  for the use of the EEA website, providing information  relevant  to  the 
public (57% respondents marked this option as ‘appropriate’ or ‘very appropriate’). 

5.12 Late implementation 

Member States perceive Article 17 as burdensome and many stakeholders supported its 
improvements. The OPC drew attention to several observations: over 50% of respondents 
agreed  with  the  measure  to  adjust  planning/reporting  under  Art.  17  to  link  better  with 
obligations/reporting  with  enabling  conditions  to  access  EU  funds.  Respondents  felt 
mostly  quite  negative  towards  the  idea  that  planning  and  implementation  obligations 
should  be  set  for  those  EU  countries  that  receive  significant  EU  funding.  Only  19% 

98   

 
 
 
 
agreed with the measure as an effective way to improve implementation. A high number 
of respondents (at least 30%) did not know or had no opinion on the matter. This may be 
because  the  subjects  were  outside  their  area  of  expertise  or  that  the  questions  were  too 
broadly  formulated  for  respondents  to  give  confident  answers.  Respondents  noted  a 
general  lack  of  funding  and  a  need  for  better  investment  planning  to  be  adjusted  for 
incorporation of other obligations, such as under the WFD, which may increase the costs 
of  effective  treatment  and  procedures.  There  were  also  requests  on  improving 
transparency on investment needs in countries to anticipate future requirements. Overall, 
those that provided a response felt political willpower needed to be improved across the 
EU and that this could come through pressure, such as infringement and sanctions, from 
the EC. 

5.13 Access to sanitation 

is  not  yet  accessible 

Sanitation 
the  same  extent.  
There  was  general  support  among  stakeholders  for  improved  access  to  sanitation  for 
vulnerable and marginalised groups.  

to  all  EU  citizens 

to 

5.14 Access to justice 

Currently, the UWWTD contains no provisions concerning access to justice. Therefore, 
this area of improvement and the associated measure are aimed at improving social 
justice for both individuals and organisations. Consultation activities aimed to establish 
stakeholder views on the issue as well as on potential measures to address the problem. 

The majority of the position papers provided recommendations for the revision of the 
UWWTD and touched upon the topic of ‘Transparency, governance and justice’. Very 
few details were provided on ways this should be improved / strengthened. 

6.  POSITION PAPERS46 

In addition to the response to the online public consultation, a total of 5747 position 
papers were received, mostly from business associations (n=25) and companies / 
business organisations (n=11). The majority of position papers submitted touched on the 
following areas of revision: ‘Fit for the Future’ (n=33), ‘Remaining loads and pollution 
of the environment’ (n=12), ‘New pollution’ (n=6) and ‘Transparency, governance and 
justice’ (n=5). Overall, there was a particular interest in circular economy, with strong 
focus on recovery and reuse of materials from sludge (n=17). There was also support for 
addressing energy efficiency and standardising audits (n=12). The EPR also stood out as 
an important measure (n=15), particularly as a tool to address pollution at source rather 
than end-of-pipe. There was interest expressed in addressing issues from storm water 
overflows (n=19) and urban run-off (n=13).  

20 additional contributions were received in 2021. The position papers can be divided 
into 2 main categories, either providing direct reflection on the stakeholder conference 
(n=3, public authorities and one NGO) or providing general inputs and suggestions 

46 The list of all the position papers received in 2021 is detailed in Appendix G Position papers from the 
WOOD report 
47 In total 59 position papers were submitted alongside the OPC submissions, two of which were duplicates  

99   

 
 
 
 
                                                           
regarding the revision of the UWWTD (n=17, public authorities, business association, 
NGO and a company). 

100  

 
 
 
 
 
ANNEX 3: WHO IS AFFECTED AND HOW? 

5.  PRACTICAL IMPLICATIONS OF THE INITIATIVE 

The following table summarise the main implications for the affected stakeholders.  

Category affected 

Possible effect 

National and 
regional 
authorities 

The EU Member States and national/regional authorities (in 
Federal States) will be involved in the implementation and 
enforcement of the revised directive, like it is the case for the 
existing Directive. Additional investments in wastewater 
infrastructure and the necessary operation and maintenance of such 
equipment will be required. As shown in section 7, the additional 
yearly costs required to implement the preferred option represents 
on average an increase of the 3,85% of the yearly expenditures of 
the sector. These costs will be covered by a combination of 
additional budgets, water tariffs and the new system of producer 
responsibility for micro-pollutants. On the basis of the existing 
financing strategies in the water sector, additional required annual 
public budgets were stimulated at € 0,791 billion/year (see section 
7.1). Part of these budgets could be covered by EU funds which 
will also be essential to cover adjustment costs. In that sense, 
National/Regional authorities will have to make sure that EU funds 
are made available and used for the water sector - when it is 
necessary.  
Also they should maintain/intensify accompanying social measures 
in case water tariffs are increased. An appropriate control of the 
new system of producer responsibility should be put in place, 
representing minor additional administrative costs compared to the 
expected financial contribution from the sector (€ 1,185 bn per 
year).  
Even if the IT tools will be provided by the EEA and the 
Commission, National/regional authorities will have to adapt their 
reporting system to the revised directive which will include new 
requirements but also key simplifications. Overall, 
National/Regional authorities will benefit from the proposed 
simplification and digitisation of reporting even if part of these 
benefits might be cancelled by additional reporting requirements on 
access to sanitation, GHG emissions or new pollutants (see Table 
11).  
The application of the revised Directive will result in better 
protection of the aquatic environment and maintaining these assets 
is of critical importance to protecting human health and the 
environment in Europe. With potential significant economic 
impacts – for instance in regions/countries where tourism is a key 
source of revenues.    

Water/wastewater 
operators 

Wastewater operators are first in line for compliance with existing 
national and European legislations related to water quality 
standards. They are responsible for collection, treatment, 

101  

 
 
 
 
monitoring and proper discharge of different waste streams. 
Wastewater operators are public, mixed or private companies 
working for the local competent authorities (municipalities or 
group of municipalities).   
Changes to the UWWTD will have direct impacts on this sector. 
Additional investments will be needed notably to better manage N 
and P but also to treat micro-pollutants where it makes sense. 
Investments will also be needed to meet energy neutrality - even if 
these investments will be profitable on the long run.  
Additional monitoring efforts will be required notably to better 
understand GHG emission and energy use and to monitor the 
achievements on the micro-pollutant reduction (see Table 11). 
On top of their existing contractual obligations with their 
municipalities or group of municipalities, wastewater operators will 
have to establish contracts with the new organisations in charge to 
implement the producer responsibility schemes for micro-pollutants 
(administrative burden estimated at € 5 million/year). At the same 
time, they will be funded for the additional investments required to 
treat micro-pollutants (1,185 € bn in total). New efforts will be also 
asked in terms of transparency but also to monitor of key 
performance’s indicators (economic, social but also environmental, 
energy and GHG) which in the mid-term is expected to contribute 
to optimise their operations and reduce their costs.   
Operators are expected also to be better involved in the permitting 
process in case of industrial release in their facilities. They will also 
be a key player of the future integrated management plans aiming 
at reducing releases from storm water overflows and urban runoff.   

The local competent authorities (mainly municipalities or group of 
municipalities) will have to ensure that enough resources are given 
to their wastewater operators to ensure the implementation of the 
measures included in the preferred option. They will have to make 
sure that national/EU budgets are reserved for their investments, 
but also that water tariffs are adapted when necessary. Local 
authorities will also play a key role in establishing and 
implementing the integrated water management plans (see section 
6.1) aiming at reducing SWO and urban runoff  : their coordination 
role between different services (urbanism, wastewater collection 
and treatment, floods, urban greening etc) is essential to ensure the 
success of such plans.  

Citizens are affected in that they pay water tariffs and taxes to 
support the wastewater treatment sector. Citizen on the other side 
benefit from clean drinking and bathing water, improved 
environmental and ecological status of the waters, preserved 
biodiversity and improvement to the public health reactiveness to 
possible outbreaks.     
Environmental protection, clean and safe bathing waters and access 
to sanitation are essential aspects of human health and wellbeing 
and contribute both socially and economically to EU citizens.  
The implementation of the preferred option will contribute to 

102  

Local competent 
authorities 
(municipalities)   

Citizens  

 
 
 
 
Water Industry 
sector 

Pharmaceutical 
and PCP’s 
industries  

Other industrial 
sectors  

improve the aquatic environment while reducing the risks 
associated with new emerging pollutants. Citizen will also directly 
benefit from health-related measures notably the surveillance of 
COVID-19 and its variants in wastewaters but also the better 
control of AMR.  
Citizen will also benefit from a better access to sanitation but also 
to key information on their operators’ performances – which is 
important as they can’t choose their operators.  Depending on the 
financing strategies of their local and national authorities, increases 
in water tariffs can be expected (estimated on average at 2,3% - see 
section 7.1). In case the whole additional cost linked to the 
implementation of the new producer responsibility schemes is 
included in the product prices, PCPs and pharmaceutical prices 
would slightly increase (0.6% on average see section 6.5).   

The water and treatment technology industry will directly benefit 
from a reinforcement of the standards, but also from measures 
aiming at expanding the scope of the Directive to smaller 
agglomerations and optimising the operations and reducing energy 
use and GHG emissions. New business opportunities to develop 
new treatment techniques while reducing GHG emissions will 
emerge from the preferred option. Innovation will be boosted 
maintaining a comparative advantage for EU water industry. At the 
time of the Evaluation, eight out of the top 15 worldwide water 
businesses were based in the EU, showing clearly the global 
business leadership of this sector. The total gross value added 
(GVA) of the water industry (collection, treatment, supply and 
sewerage) reached € 43.84 billion, or 0,35% of the total EU28 
value added in 2010 (Eurostat, 2013). In the context of changes to 
the UWWTD, additional jobs could be created as well as new skills 
(digitalisation, advanced treatment).  

PCPs and the Pharmaceutical industry will have to set up new 
‘Producer responsibility’ organisations and finance their 
operations.  As explained in section 6.5 and further detailed in 
Annex 9, these industries will have the choice to either pass these 
new costs in the price of their products (max increase of 0.59%) or 
reduce their profit margins on these products (average maximum 
impact of 0.7).  

Inefficiencies in wastewater treatment and subsequent pollution 
have direct negative impact on the EU economy and industry. 
Multiple industry sectors are highly dependent on sufficient 
treatment of wastewater, and clean water quality. For example, 
water for the food industry or for irrigation in agriculture, provision 
of drinking water, tourism and recreational industry. Improved 
water quality as a result of the application of the preferred option 
will positively affect these sectors.  
Since micro-pollutants are not entirely biodegradable, they can 
pose a risk to drinking water resources and aquatic ecosystems. The 
application of the preferred option will avoid putting additional 

103  

 
 
 
 
Environment 

burdens on drinking water providers who must rely on sufficient 
clean water resources (surface and groundwater) so that they can 
fulfil their task to ensure healthy and safe drinking water.  
Water quality and security affects agriculture as well, which can 
use up to 80% of water in Southern regions (EIB, 201648). Given 
that the dominant use of water is for agricultural irrigation (global 
average is 70%49), the economic consequences of poor water 
quality and water scarcity are most pronounced in agriculture-
dependent economies. 

Protection of aquatic ecosystems and water resources is a key 
ambition of the UWWTD and in coherence with the WFD, targets 
treating water for pollution to enable favourable conditions for 
aquatic life.  With the preferred option, the expected reduction of 
organic matter and other pollution in treated wastewater will 
improve water quality throughout the European Union. Water 
quality improvements lead to an increased provision of ecosystem 
services such as recreational benefits of improved bathing waters 
and tourism. The impacts include direct and indirect impacts on 
fisheries, recreation (including human health), biodiversity and the 
production of drinking water.50 
According to a report published by the EEA, the effectiveness of 
national water policies and many years of investment in better 
wastewater treatment and sewerage systems has led to Europe’s 
bathing water being much cleaner today than it was decades ago.  
As shown in the Evaluation of the UWWTD, the implementation of 
the Directive has almost doubled the river length with at least good 
quality, from 43.5% in the pre-Directive scenario to 82,9% under 
full compliance. The implementation of the UWWTD is estimated 
to have increased the length of coastlines with at least good quality 
from 73,5% in the pre-Directive scenario to 95,2% under full 
compliance which would be a direct benefit for citizens using these 
waters. These percentages are expected to further increase with the 
implementation of the preferred option (% to be added).   
Differences in the implementation and interpretation of the 
UWWTD principles and procedures across Member States can 
limit the protection of the environment, creating transboundary 
issues and directly affecting the functioning and effectiveness of 
the Directive in reducing pollution with subsequent impacts on EU 
society. Approximately 60% of the EU's rivers run across borders 
of Member States (and non-Member States). If waters are of poor 
quality in an upstream Member State, this may have impacts on any 
downstream Member State. Action taken by all Member States is 
therefore required so that cross border environmental problems can 

48 European Investment Bank, (2016), Restoring European Competitiveness, Luxemburg 
49 OECD, (2020), Financing Water Supply, Sanitation and Flood Protection: Challenges in EU 
Member States and Policy Options  
50 Milieu and COWI, (2016), Study to assess the benefits delivered through the enforcement of 
EU environmental legislation 

104  

 
 
 
 
                                                           
be mitigated and water quality improved. 

6.  SUMMARY OF COSTS AND BENEFITS 

The annual overall costs and benefits of the preferred option by 2040 are presented below.  

I.  Overview  of  Benefits  (total  for  all  provisions)  –  Preferred  Option  -  A  breakdown  per  MS  is  provided  in  Annex  7, 
Table A7.6 (total costs and benefits).  

Description 

Amount 

Direct benefits 

Comments 

Monetised  benefits  due 
reduced 
emissions  of  Nitrogen,  Phosphorus  and 
BOD in the environment and willingness to 
pay for SWOs/urban run off  

to 

Benefits  mainly  for  the  environment  and 
public health (notably bathing and drinking 
water),    for  biodiversity  (protection  of 
fauna)  

Monetised  benefit  due  to  GHG  emission 
reduction  from  improved  process  (N2O 
emissions) and energy neutrality  
Direct savings due to energy neutrality  

Improvement 
quality  

of  water 

     €        6.156.474.955 /year 

Reduction  of  the  toxic  load 
in receiving waters  

44% reduction of  the toxic load rejected to 
receiving waters of which 64% happening in 
areas at risk (with low dilution rates)   

Reduction 
emissions 
neutrality  

of 
and 

GHG 
energy 

          €    486.370.454 /year (GHG reduction)  

    € 0 (2 bn /year savings due to energy 
neutrality compensated by the costs to reach 
energy neutrality - see section 6.7)  

Indirect benefits 

Improved  bathing  water 
quality  

Significant  reduction  of  E.  coli  emissions  (key 
parameter for bathing water quality), impacts on 
tourism, well-being in the cities  

Improved  raw  water  for 
drinking water  

Improved  protection  of  the  raw  water  used  for 
drinking  water,  reduced  health  risks,  reduced 
treatment costs for water operators  

Biodiversity   

Public Health  

EU water industry  

Innovation  

is 

essential 

Cleaner  water 
to  preserve 
biodiversity  on  the  rivers,  lakes  and  coastal 
areas.  Actions  on  SWO  and  urban  runoff  will 
incentivize actions to ‘green’ the cities 

Monitoring  COVID-19  and  its  variants  as  well 
as  Anti-Microbial 
is  providing 
precious information for public health  

resistance 

business 

opportunities. 

for 
New 
innovation, modernisation and transition towards 
climate neutral industry. Maintain/amplify of the  
worldwide leadership of the EU water industry    

Push 

Energy and Climate neutrality as well as micro-
pollutant  treatment  are  new  and  will  drive 
innovation.  Same  for 
improved  N  and  P 
efficiency   

Administrative cost savings related to the ‘one in, one out’ approach  

National 
database for reporting   

digitalised 

Potential  savings  for  operators  compensated  by 
additional 
reporting  more 
parameters 

costs  due 

to 

Better  coherence  reporting 

Modest savings  

105  

 
 
 
 
 
 
           
           
  
 
     
 
 
 
 
 
 
with E-PRTR  

II. Overview of costs – Preferred option - A breakdown per MS is provided in Annex 7, Table A7.6 (total costs and 
benefits) and in Table A7.5 (detailed costs per MS). Costs are annual costs by 2040 including capex and opex.   

Citizens/Consumers 

Wastewater operators/ 
municipalities   

National/regional 
administrations 

One-off 

Recurrent 

One-off 

Recurrent 

One-off 

Recurrent 

€/year in 
2040 

€/year in 2040 

€/year in 
2040 

SWO and 
urban run  
-off    

Direct adjustment 
costs 

Administrative 
costs 

Small 
scale 
agglomer
ations      

Direct 
adjustment costs 

Administrative 
costs 

Nutrients 
removal    

Direct 
adjustment costs 

Administrative 
costs 

Micro-
pollutant
s 
removal    

Direct 
adjustment costs 

Administrative 
costs 

Direct 
adjustment costs 

GHG 
and 
energy 
neutralit
y    

Administrative 
costs 

6.446.657.281 

372.472.648 

57.600.000 

    1.141.228.243  

140.406.278 

472.000 

12.129.508.400  

2.008.825.659 

0   

8.891.344.396 

1.213.112.586  

27.600.000  

0  

(1.560.000 
€/year 
compensated 
by direct 
savings – see 
section 6.7)   

Audits –
(6.000.000 
and 
monitoring - 

106  

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    
 
 
 
 
 
 
 
 
 
 
     
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Other 
actions     

Direct 
adjustment costs 

Administrative 
costs 

Average 
increase of 
water tariffs 
of 2,26% - 
or € 
1.806.000 
/year  

No changes  

98.700.000 
compensated 
by direct 
savings – see 
section 6.7)   

55.700.000 
million AMR 
+ COVID-19 
+ non 
domestic 
waters  

Average 
increase in 
public 
budget of 
774 million  

 Neutral  

Costs related to the ‘one in, one out’ approach (PCP’s and pharmaceutical industry) 51 

Direct adjustment 
costs  

Total   

Indirect 
adjustment costs 

Administrative 
costs (for 
offsetting) 

8.891.344.396  € 
for PROs to cover 
investments for 
micro-pollutants 
advanced 
treatment 
between entry in 
force and 2040 

  16,2 million 
€/year to be 
shared between 
PRO (11,2 
million)  and 
industry (5 
million)  

51 As explained in section 6.11 the private and mixed private/public companies will face additional 
administrative costs (€ 39,29 million per year). These additional costs will nevertheless be passed on the 
competent public authorities having contracts with these operators and/or compensated by the expected 
gains due to the application of the energy neutrality target.    

107  

 
 
 
 
 
 
 
 
 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                           
 
 
108  

 
 
 
 
 
 
 
7.  RELEVANT SUSTAINABLE DEVELOPMENT GOALS  

Relevant SDG 

Expected progress towards the Goal 

Comments 

SDG  no.  6  –  ‘Ensure 
availability 
and 
sustainable  management 
of  water  and  sanitation 
for all’  
Targets  6.2,  6.3,  6a  and 
6b.  

lives 

SDG  no  3  –  ‘Ensure 
healthy 
and 
promote  well-being  for 
all at all ages’ 
Targets  3.3:  By  2030, 
end  the  epidemics  of 
tuberculosis, 
AIDS, 
malaria  and  neglected 
tropical  diseases  and 
combat  hepatitis,  water-
borne diseases and other 
communicable diseases.  

and 
2030, 
3.9  By 
substantially  reduce  the 
number  of  deaths  and 
illnesses from hazardous 
chemicals and air, water 
and  soil  pollution  and 
contamination 

SDG no 14 – ‘Conserve 
and  sustainably  use  the 
oceans,  seas  and  marine 
resources for sustainable 
development’ 
Target  14.1  “By  2025, 
prevent 
and 
reduce 
significantly 
marine  pollution  of  all 
kinds, in particular from 
land-based 
activities, 
including  marine  debris 
and nutrient pollution” 

population 

Increased 
to 
sanitation  systems  by  actions  to  improve 
access to sanitation but also extending the 
scope to smaller facilities.   

connected 

of 

implementation 

The  Directive  directly  contributes  to 
the 
the 
requirements  of  SDG  6.  The  level  of 
treatment as well as the collection rate 
of the EU is one of the most advanced 
worldwide.  With  the  revision  of  the 
Directive, 
intensified 
this  will  be 
(reinforcement  of  the  standards,  new 
treated,  more 
parameters 
agglomerations 
the 
by 
Directive).  The scope of the Directive 
could  also  be  expanded  to  ensure 
access to sanitation.   

covered 

to  be 

Monitoring  of  health  relevant  parameters 
in wastewater will contribute to improved 
public health (Covid 19, AMR others).  

The  Directive  directly  contributes  to 
the implementation of specific parts of 
the  targets  of  SDG  3,  in  particular 
targets 3.3 and 3.9.  

removal  of  pollutants 

Increased 
in 
wastewater  released  to  water  bodies  will 
contribute  to  reduce  hazards  due  to  water 
pollution 
(bathing-g  waters,  drinking 
water).  

Increased  removal  of  pollutants  including 
contaminants, 
in 
plastics, 
wastewater  will  reduce  pollution  going  to 
seas. 

nutrients 

The  Directive  directly  contributes  to 
the implementation of specific parts of 
target 14.1 of SDG 14  

109  

 
 
 
 
 
 
 
 
 
 
 
ANNEX 4: ANALYTICAL METHODS 

In line with previous assessments in the context of the Evaluation of the Directive52, the 
JRC  has  developed  ad-hoc  model  calculations  tailored  for  the  policy  questions  of  this 
impact assessment. 

1.  Quantification of emissions reduction and costs for current and scenario 

conditions 

Addressing  the  questions  required  mainly  the  quantification  of  costs  of  action  and 
changes  in  water  pollutant  and  greenhouse  gas  (GHG)  emissions  following  from  the 
implementation  of a set  of measures  at  selected  wastewater treatment  plants. Pollutants 
addressed  include  organic  matter  (as  biochemical  oxygen  demand,  BOD),  nutrients  (as 
total  N  and  total  P),  faecal  coliforms,  and  micro-pollutants.  GHG  emissions  are 
represented as carbon dioxide equivalent (CO2e) emissions.   

All  calculations  ground  on the  database of wastewater treatment  plants (WWTPs) from 
the  10th  UWWTD  Implementation  report.  For  each  WWTP,  we  assume  an  emission 
factor expressed as:  

- 

- 

 mass of BOD, N or P per population equivalent (pe) per day;   

coliforms colony-forming units (CFU) per p.e. per day;  

-  normalized toxic units (TU) of micro-pollutants per p.e. per day;  

-  GHG emissions as kg CO2e per p.e. per day.  

The emission factors are attributed on the basis of the level of treatment and the treated 
population equivalents of the plant.  

For each policy scenario, we modify one or more of the emission factors (depending on 
the measures foreseen in the policy) for those WWTPs to which the policy applies. The 
product of an emission factor by the treated population equivalents of the plant yields the 
emissions  from  the  plant.  The  sum  of  emissions  from  plants  within  one  Member  State 
(MS)  or  the  total  for  the  EU  indicate  the  aggregated  effect  of  a  policy  scenario  on 
emissions.  In  a  similar  way,  for  each  plant  we  calculate  the  cost  of  implementing  a 
measure based on appropriate assumptions, and consequently the MS and EU total costs.  

Therefore,  the  quantification  of  present  conditions  and  scenarios  in  this  impact 
assessment  is  based  on  simple  Excel  calculations  that  are  all  similar  in  structure,  but 
differ for the issue addressed each time in terms of emission factors and costs.  

The emission factors for coliforms, BOD, N and P, based on Pistocchi et al., 201913 but 
slightly adapted for N and P, are summarized in Table A4. 1.  

52 https://publications.jrc.ec.europa.eu/repository/handle/JRC115607  

110  

 
 
 
 
 
 
                                                           
Removal 
efficiency of 
secondary 
treatment 

Removal 
efficiency of 
tertiary 
treatment 

Substance 

Emission factor 
(g/p.e./day) 

BOD 

60 

N 

P 

Varies slightly by 
country, average 11.18 

Varies slightly by 
country, average 1.34 
(excreta) and 0.34 
(detergents) 

Removal 
efficiency 
of 
primary 
treatment 

50% 

25% 

94% 

50% 

30% 

55% 

96% 

75% 

85% 

Faecal coliforms 

1.23 x 1010 (*) 

40% 

90% 

99% (**) 

Table  A4.  1–  Emission  factors  for  N,  P,  BOD  and  coliforms.  After  treatment,  the  emission 
factor  is  multiplied  by  (100  –  removal  efficiency)/100.    (*)  for  coliforms,  units  of  the  emission 
factor are CFU/PE/day ; (**) for N removal : if only P removal, efficiency is 90%. 

The emission factors for micro-pollutants are estimated as the sum of concentrations of a 
list  of several  representative micro-pollutants,  each divided by  an appropriate threshold 
indicative  of  toxic  risks.  For  the  modelling  of  micro-pollutant  removal  in  wastewater 
treatment  plants  we  use  the  SimpleTreat  model53,  used  for  risk  assessment  within  the 
European  Union  System  for  the  Evaluation  of  Substances  (EUSES)54.  For  advanced 
treatment,  we  refer  to  measured  removal  efficiency  in  ozonation  and  adsorption  on 
activated carbon for a set of representative substances.  

All  details  of  the  analysis,  including  an  in-depth  discussion  of  assumptions  and 
limitations,  are  presented  in  Pistocchi  et  al.,  2022a55  containing  also  all  the  data  on 
micro-pollutant properties used for the estimation. Table A4. 2 summarizes the emission 
factors  adopted  in  the  impact  assessment.  This  representation  of  emission  factors  is 
equivalent  to  assigning  “weights”  to  the  discharges  of  wastewater  subject  to  different 
treatments, so that the results appear as “untreated wastewater equivalent discharges”.  

Level of treatment 

Emission factor (normalized TU) 

Untreated wastewater 

Primary treatment effluents 

Secondary treatment effluents 

Tertiary treatment effluents 

1.0000 

0.6595 

0.3148 

0.2955 

53 https://www.rivm.nl/en/soil-and-water/simpletreat  
54 https://echa.europa.eu/support/dossier-submission-tools/euses  
55 Supporting Report 13 in Annex 10 

111  

 
 
 
 
 
                                                           
Advanced treatment effluents 

0.0783 

Table A4. 2– Emission factors for micro-pollutants, expressed as dimension less toxic units and 
normalized by assigning a unit value for untreated wastewater.  

A  specific  model  of  GHG  emissions  has  been  developed  for  this  impact  assessment 
(Parravicini  et  al.,  202256)  drawing  on  the  2019  refinement  of  the  IPCC  Guidelines  for 
national  GHG  inventories.  The  emissions  of  a  WWTP  depend  on  various  design  and 
operational parameters that are not known for the plants included in the database used for 
the  assessment.  Therefore  an  emission  factor  was  estimated  for  a  set  of  typologies  of 
plant  configurations.  For  each  plant,  we  considered  the  average  of  emissions  from  the 
typologies compatible with the plant’s size and level of treatment. Figure A4. 1 plots the 
emission factors for the typologies considered in Parravicini et al., 202217.  

56 Supporting report 9 in Annex 10 

112  

 
 
 
 
                                                           
Figure A4. 1– Emission factors for the typologies of plant configurations considered in the IA.  

For  the  Evaluation  of  costs  of  conventional  wastewater  treatment  we  used  the  OECD-
endorsed  FEASIBLE  model57  to  quantify  the  costs  of  upgrading  a  WWTP  from 
secondary  to  tertiary  treatment.  In  particular,  we  refer  to  the  expenditure  functions 
described  in  Appendix  3  of  the  model  documentation58,  as  updated  more  recently  in  a 
study on the costs of compliance with the UWWTD59.  

57 https://www.oecd.org/env/outreach/methodologyandfeasiblecomputermodel.htm  
58 https://www.oecd.org/env/outreach/36227787.pdf  
59 https://ec.europa.eu/environment/water/water-urbanwaste/info/pdf/Cost%20of%20UWWTD-
Final%20report_2010.pdf  

113  

 
 
 
 
 
                                                           
For  the  costs  of  advanced  treatment  for  the  removal  of  micro-pollutants,  we  used  the 
simple expenditure function proposed and discussed in Pistocchi, 2022b60. For the costs 
of  treatment  of  small  agglomerations,  we  used  a  combination  of  costs  from  the 
FEASIBLE expenditure functions and the expenditure functions proposed in a study on 
the Danube region (Pistocchi et al., 2020)61.  

All details on the calculation of costs of upgrade for nutrient removal, as well as micro-
pollutant  removal,  are  presented  in  Pistocchi  et  al.,  2022b62,  and  in  Pistocchi  et  al., 
2022c63.  Details  on  the  costs  of  extending  the  scope  of  the  UWWTD  to  smaller 
agglomerations  are  provided  in  Pistocchi  et  al.,  2022d64.  For  the  quantification  of  the 
benefits,  we  have  assumed  a  shadow  price  of  avoided  BOD  emissions  of  50  €/t,  and  a 
shadow price of 1 kg of avoided N or P equal to 20 and 30 €, respectively24.  For GHG 
emissions, we assume a shadow price of 100 Euro/t CO2e. 

For coliforms, micro-pollutants and micro-plastics, it was not possible to identify a valid 
shadow price. The benefits of removing these pollutants are therefore not quantified.  

2.  Modelling impacts of policy scenarios at the level of the whole stream network  
While most of the policy options are evaluated on the basis of the above calculations, for 
nutrients and micro-pollutants we quantified the change in the conditions of the receiving 
water  bodies  through  appropriate  indicators.  For  nutrients,  we  used  the  GREEN  model 
(Grizzetti  et  al.,  202165) to compute the discharges of N  and P to  the EU  regional seas 
taking  into  account  also  other  sources  of  nutrients  (agriculture,  atmospheric  deposition 
etc.). For micro-pollutants, we computed the distribution of toxicity, both at the discharge 
point for individual WWTPs, and for the whole stream network taking into account the 
accumulation  of  contaminants  from  upstream  to  downstream.  These  calculations  are 
further discussed in detail in Pistocchi et al., 2022a16 and Pistocchi et al., 2022c24. 

3.  Modelling costs and impacts of policy scenarios on storm water overflows (SWO) 
SWO are a potentially significant source of pollution in Europe. However, we lack data 
and  knowledge  about  their  current  occurrence  and  existing  management  practices.  In 
order  to  support  the  analysis  of  policy  options,  we  have  developed  a  dedicated 
hydrological model (Quaranta et al., 2022a66) that was reality-checked with satisfactory 
results  (ibid.).  The  model  was  then  used  to  appraise  the  impacts  and  costs  of  various 
action strategies, representative of policy scenarios. The results are discussed in detail in 
Quaranta et al., 2022b67. 

4.  Model uncertainties  
The main uncertainties linked with the use of the models are concisely recalled here for 
each  area  of  model  application.  When  feasible  and  relevant,  a  sensitivity  analysis  was 
performed  to  better  understand  the  limits  of  the  model.  In  general  terms,  it  should  be 
stressed that:  

60 See Annex 10, report 14  
61 https://publications.jrc.ec.europa.eu/repository/handle/JRC115606  
62 Supporting report 15 in Annex 10  
63 Supporting report 14 in Annex 10 
64 Supporting report 10 in Annex 10  
65 https://www.sciencedirect.com/science/article/pii/S0959378021000601  
66 Supporting report 17 in Annex 10 
67 Supporting report 18 in Annex 10  

114  

 
 
 
 
                                                           
  Cost estimates are uncertain at least within a factor 2 in absolute terms. Costs of 
all policy measures  depend on local  conditions  warranting  for a high variability 
and specificity of costs.  

  The quantification of impacts varies with the emission factors in a linear way, so 
the uncertainties on emission factors reflect directly in uncertainties on impacts.  

  The  uncertainties  on  individual  emission  factors  are  high  and  (in  some  cases) 
difficult to even quantify. However, for the impact assessment the relative change 
in  emission  factors  among  scenarios  is  most  important,  and  is  expected  to  be 
much less uncertain.  

 

In  order  to  make  sure  that  uncertain  emission  factors  do  not  yield  misleading 
conclusions  for  policy,  we  have  complemented  the  more  “technical”  sensitivity 
analysis  and  discussion  of  uncertainty  with  a  qualitative  assessment  of  the 
“safety” of assumptions, where we show that even stretching the assumptions to 
the  limits  of  plausibility  would  not  significantly  affect  the  conclusions  of  the 
impact assessment. Further details are provided in the following sections.  

5.  Detailed analytical methods – micro-pollutants  
Quantification of policy impacts68 

The impact of implementing of advanced treated is evaluated by analysing how two 
indicators of water pollution change under different policy scenarios.  

The first one (L) is an indicator of aggregated toxic loads with reference to a set of m 
WWTPs and l agglomerations in the EU:  

𝑙

𝑙

𝑚

𝑚

𝐿 = 𝑤0 ∑ 𝑃𝑘

𝛿0,𝑘 + 𝑤𝐼 ∑ 𝑃𝑘

𝛿𝐼,𝑘 +   𝑤𝐼 ∑ 𝑃𝑗

𝛿𝐼,𝑗 +   𝑤𝐼𝐼 ∑ 𝑃𝑗

𝛿𝐼𝐼,𝑗

𝑘=1

𝑘=1
𝑚

𝑗=1
𝑚

𝑗=1

(Eq 1) 

+   𝑤𝐼𝐼𝐼 ∑ 𝑃𝑗

𝛿𝐼𝐼𝐼,𝑗 +   𝑤𝐼𝑉 ∑ 𝑃𝑗

𝛿𝐼𝑉,𝑗 

𝑗=1

𝑗=1

Where:  

-  𝑤0, 𝑤𝐼,  𝑤𝐼𝐼,  𝑤𝐼𝐼𝐼,  𝑤𝐼𝑉  are  the  emission  factors  (normalized  toxic  units)  for 
untreated  wastewater  and  wastewater  treated  at  primary,  secondary,  tertiary  or 
advanced level (),   

-  Pk  is  the  wastewater  load,  expressed  in  population  equivalent  (pe),  in  the  k-th 

agglomeration,   

-  Pj the wastewater load treated by the j-th WWTP in pe, 
-  𝛿0,k and 𝛿I,kthe fractions of Pk that are untreated or treated mechanically, 
-  𝛿𝐼,𝑗,  𝛿𝐼𝐼,𝑗,  𝛿𝐼𝐼𝐼,𝑗  and  𝛿𝐼𝑉,𝑗  are  Boolean  variables  equal  to  1  if  the  j-the  WWTP 
provides  mechanical,  biological  carbon  removal  or  denitrification  or  advanced 
treatment, respectively, and 0 otherwise. 

The  data  on  agglomerations  and  wastewater  treatment  plants  are  drawn  from  the  10th 
UWWTD implementation report database. Indicator L is expressed in units of population 
equivalents (p.e.).  

68 All details of the modelling summarized here are presented and discussed in Pistocchi, 2022a55 

115  

 
 
 
 
 
                                                           
The  “population  equivalents”  of  an  emission  represent  the  discharge  of  pollutants 
expressed  in  terms  of  the  number  of  persons  that  would  generate  the  same  discharge 
(before  any  treatment).  So  for  instance  a  WWTP  treating  100  thousand  p.e.  with  a 
removal  efficiency  of  BOD  of  95%  corresponds  to  a  discharge  of  100  x  (1-0.95)=  5 
thousand  p.e.  for  BOD.  The  same  plant  would  correspond  e.g.  to  20  thousand  p.e.  for 
total  N  if  its  N  removal  efficiency  were  80%.  p.e.  of  discharges  must  be  always 
interpreted with reference to a specific contaminant, as highlighted by the above example 
with BOD and N.  Referring to p.e. instead of more physical units (e.g. tonnes per year) 
enables  presenting  results  on  the  same  scale  for  all  pollutants  of  concern  (BOD,  N,  P, 
coliforms, micro-pollutants).  

Converting  p.e.  to  tonnes/year  is  always  possible,  provided  that  we  know  the  emission 
per capita.  This  is  the case for  BOD (60  g/PE/day),  N (roughly 11-12  g/PE/day)  and P 
(roughly  1.5  g/PE/day).  In  certain  cases  (e.g.  micro-pollutants),  we  do  not  know  the 
emission  per  capita.  In  these  cases,  we  can  still  compute  p.e.  if  we  know  the  removal 
efficiency  of  different  types  of  treatment.  These  are  the  reasons  why  the  results  are 
presented  in  terms  of  p.e.  A  practical  advantage  is  also  that  p.e.  are  relatively  easy  to 
visualize: for instance, if we say that EU CSO convey 9 million p.e. of pollution, we can 
imagine them as the total load (before any treatment) of the population of Austria. 

The  second  one  (CT)  takes  the  form  of  a  map  accounting  for  the  accumulation  of  all 
toxic loads from their point of release along the stream network. At a point (x,y) in the 
stream network the map is computed as:  

𝐶𝑇(𝑥, 𝑦) = 𝑤0

∫
𝐴(𝑥,𝑦)

𝑃0(𝜉,𝜁)𝑑𝜉𝑑𝜂
𝑄(𝑥,𝑦)

+𝑤𝐼

∫
𝐴(𝑥,𝑦)

𝑃𝐼(𝜉,𝜁)𝑑𝜉𝑑𝜂
𝑄(𝑥,𝑦)

+𝑤𝐼𝐼

∫
𝐴(𝑥,𝑦)

𝑃𝐼𝐼(𝜉,𝜁)𝑑𝜉𝑑𝜂
𝑄(𝑥,𝑦)

+𝑤𝐼𝐼𝐼

∫
𝐴(𝑥,𝑦)

𝑃𝐼𝐼𝐼(𝜉,𝜁)𝑑𝜉𝑑𝜂
𝑄(𝑥,𝑦)

(Eq 2) 

+ 𝑤𝐼𝑉

∫
𝐴(𝑥,𝑦)

𝑃𝐼𝑉(𝜉,𝜁)𝑑𝜉𝑑𝜂
𝑄(𝑥,𝑦)

Where: 

-  𝑃0(𝑥,𝑦), 𝑃𝐼(𝑥,𝑦), 𝑃𝐼𝐼(𝑥,𝑦), 𝑃𝐼𝐼𝐼(𝑥,𝑦), 𝑃𝐼𝑉(𝑥,𝑦)  are the wastewater discharges at  location 

(x,y) (expressed in PE) subject to no treatment, mechanical, biological treatment 

for carbon removal, for nitrogen removal and advanced treatment, respectively,   

-  𝑄(𝑥,𝑦) is the diluting discharge at (x,y),  A(x,y) is the drainage area at point (x,y).  

Wastewater  discharges  accounted  for  include  not  only  WWTPs  and  releases  from  IAS 
and  untreated  wastewater  in  agglomerations,  but  also  discharges  from  other  European 
countries not reported under the UWWTD, as well as smaller agglomerations outside the 
scope of the UWWTD. The map CT(x,y) is computed at the cells (x,y) of a regular grid 
of 5 km  resolution  over  Europe in  a GIS using standard map-algebraic operations  with 
flow accumulation operators as described in detail in Pistocchi, 201469.  

Indicator CT is expressed in the rather abstract units of p.e. m-3 s, but can be interpreted 
in a more informative way if we assume a certain emission rate per p.e. For the sake of 
illustration,  we  refer  to  the  example  of  diclofenac,  a  drug  commonly  considered  of 

69 https://onlinelibrary.wiley.com/doi/book/10.1002/9781118523667  

116  

 
 
 
 
 
 
 
 
                                                           
concern for which we can assume an environmental quality standard (EQS) of 100 ng/L 
(Ort et al., 2009; EC, 2012). If we assume that a p.e. corresponds to an emission of 240 
ug/day  of  diclofenac  to  wastewater  (ibid.),  then  1,000,  10,000  and  50,000  p.e.  m-3  s 
correspond to a concentration of about 3 ng/L, 30 ng/L and 150 ng/L, respectively. These 
concentrations are estimated assuming an annual average discharge, and may be higher 
during low flow, or lower during high flow conditions.  

Therefore  our 
thresholds  may  be  regarded  as  discriminating  situations  where 
concentrations  are  low  (<1,000  p.e.  m-3  s),  medium-low  (1,000-10,000  p.e.  m-3  s), 
medium-high (usually below EQS but at risk of exceedance in case of low flows: 10,000-
50,000 p.e. m-3 s) and high (usually above EQS: > 50,000 p.e. m-3 s). This categorization 
is based on diclofenac, and would be valid for any other micro-pollutant having a similar 
ratio between emission rate (ER) and EQS. For micro-pollutants with higher ER/EQS, a 
lower amount of p.e. could be conveyed per m3 s-1 of streamflow before exceeding the 
EQS, and the other way around for micro-pollutants with lower ER/EQS. 

The  calculation  of  indicator  L  is  performed  in  MS  Excel,  while  CT  is  computed  using 
ArcGIS 10.7 (Spatial Analyst extension).  

The  analytical  structure  is  simple  and  transparent,  and  calculations  can  be  followed  in 
details (e.g. by inspecting Excel formulas and ArcGIS command scripts).  

The indicators are used as proxy of the toxic pollution associated with wastewater under 
the following key assumptions, limitations and simplifications: 

1.  The chemical mixture composition of wastewater is constant across the EU and in 

time.  

2.  The  assumed  concentrations  of  individual  micro-pollutants,  on  the  basis  of 

available measurements, are representative.   

3.  Advanced  treatment  is  assumed  to  consist  of  ozonation,  activated  carbon  or  a 
combination of the two in different process configurations. The latter are assumed 
to be largely equivalent to each other in terms of aggregated toxicity reduction.  

4.  The  removal  of  micro-pollutants  in  conventional  wastewater  treatment  is 
represented  by  the  SimpleTreat  model  using  the  partitioning  and  degradation 
properties of the substances that can be inferred from the available data. 

5.  For  advanced  treatment,  the  removal  efficiency  is  represented  by  measured 
removal  efficiencies  of  the  known  chemicals.  In  the  case  advanced  treatment 
removal  efficiency  for  a  substance  is  not  known,  we  assume  the  substance  is 
removed as the average of the known substances. This assumption is particularly 
critical as the available data on removal are limited, and in practice the majority 
of chemicals is removed as the average.   

6.  Additionally,  for  indicator  CT  we  consider  only  toxicity  caused  by  wastewater 
(neglecting  e.g.  urban  runoff,  agricultural  pesticides,  industrial  chemicals  and 
other  emissions  potentially  overriding  the  effect  of  wastewater.  Moreover,  we 
consider  the  micro-pollutants  as  conservative  in  the  stream  network  after 
discharge.  

117  

 
 
 
 
The above assumptions are apparently crude approximations laden with limitations (see 
Pistocchi  et  al.,  2022a,  for  more  details).  However,  their  introduction  leads  to  the 
estimation of the toxicity emission factors shown in Table A4. 2, which is reasonably in 
line with the expectations: the toxicity of untreated wastewater is reduced by a factor > 3 
with conventional treatment, which may allow meeting environmental quality standards 
in  many  cases,  but  advanced  treatment  is  needed  to  reduce  toxicity  by  one  order  of 
magnitude or more. Measurements suggest that advanced treatment may reduce toxicity 
even  more,  but  this  would  only  strengthen  the  recommendations  deriving  from  this 
modelling exercise.  Therefore, it can be concluded that the representation is  acceptable 
insofar  as  not  misleading.  For  indicator  CT,  neglecting  other  sources  of  contamination 
may  be  appropriate  for  those  chemicals  (such  as  pharmaceuticals)  for  which  urban 
wastewater  is  expected  to  be  a  key  driver.  For  other  classes  of  pollutants,  wastewater 
may be a minor, or anyway a secondary source.  

In  addition  to  the  impacts  in  terms  of  toxicity  indicators,  we  have  quantified  the 
greenhouse gas (GHG) emissions  of advanced treatment, assuming an average emission 
factor of 0.225 kg CO2e/m3 of wastewater treated, and a wastewater volume to treat of 
200 L/PE/day21.  

The approach has been developed in collaboration with a network of leading experts in 
Europe, presented at  specific workshops and meetings with  stakeholders  and subject  to 
scientific  peer-review  in  fully  open  access  form  (including  supporting  material  with  all 
the data used in the calculation)16.  

Quantification of policy costs70 

The  cost  of  advanced  treatment  (€/PE/year  including  investments  and  operation)  is 
described by the following simple expenditure function:  

Cadv=1000 PE-0.45 

(Eq 3) 

This  function  corresponds  to  the  available  evidence  and  is  accurate  within  a  factor  2 
(Pistocchi  et  al.,  2022b21).  In  addition  to  the  costs  of  advanced  treatment,  in  some 
scenarios certain WWTPs might be required to implement advanced treatment even if not 
currently  required  to  perform  nitrogen  removal  (tertiary  treatment).  In  this  case,  we 
calculate also a cost of upgrading the plant from secondary to tertiary treatment. To this 
end,  we  assume  the  costs  of  upgrade  to  correspond  to  the  difference  between  costs  of 
new  tertiary  and  secondary  plants,  plus  50%  of  the  costs  of  a  new  secondary  plant  to 
account for the potentially significant infrastructural overhaul. The costs of upgrade are 
described  with  the  FEASIBLE  expenditure  functions19,  20.  This  cost  is  likely 
overestimated and provides a “worst case” bound to the overall costs. In the calculation, 
we assume a lifetime of the investment of 30 years, and a discount rate of 2.5%. 

The  method  has  been  designed  in  order  to  explore  the  trade-offs  between  costs  and 
effectiveness  of  advanced  wastewater  treatment  for  micro-pollutant  removal.  The 
calculation is quick and transparent and enables comparing several scenarios in order to 
define precisely the Pareto front of trade-offs.  

70 Supporting report 15 in Annex 10  

118  

 
 
 
 
                                                           
As  a  starting  point,  we  compute  the  indicators  L  and  CT  for  the  present  conditions 
(“baseline”)  and  the  conditions  of  full  compliance  with  the  current  directive,  not  yet 
achieved although quite close in reach.  

We  also  assume  that,  in  the  absence  of  a  specific  provision,  advanced  treatment  will 
not  be  implemented.  This  is  a  “pessimistic”  assumption,  because  some  initiatives  are 
already  being  undertaken  notably  in  Germany,  Sweden,  Denmark  and  the  Netherlands. 
However,  stakeholder  consultations  and  Member  State  surveys  (see  Annex  5)  have 
highlighted how in most of the EU there is no appetite for advanced treatment, and even 
within  the  above  mentioned  countries  the  subscription  to  advanced  treatment  is  not 
always enthusiastic due to the relatively high costs entailed.  

We then compare the baseline and full compliance scenarios with scenarios of advanced 
treatment implemented at all plants above a certain treatment capacity (expressed as PE), 
and when the dilution ratio (annual average flow of the receiving water body divided by 
the  effluent  discharge)  is  less  than  a  minimum  value.  Pistocchi  et  al.,  2022a16  and 
Pistocchi et al., 2022b21 present a systematic exploration of all combinations of capacity 
thresholds between 0 and 1 million PE, and dilution thresholds between 2 and infinity.  

For each scenario, the calculated indicator L is compared with those under baseline and 
full  compliance  scenarios.  Moreover,  for  each  scenario  we  can  compute  the  costs  of 
advanced  treatment  (and  the  additional  costs  of  upgrading  conventional  treatment  from 
secondary to tertiary), and the value of L plotted as a function of the corresponding costs 
indicates the cost-effectiveness of the scenario. While L is a scalar number, indicator CT 
is a map. In order to compare CT maps for the baseline/full compliance and the various 
scenarios, we refer to the percentage of the stream network (on which CT is computed) 
under conditions of “high”, “medium”, and “low” toxicity as discussed above. While the 
reader is referred to the supporting reports16, 21 for the full exploration of scenarios, here 
we focus on representative scenarios:  

- 

- 

- 

“low  ambition”:  all  plants  with  a  treatment  capacity  of  100,000  p.e.  or  more, 
discharging  in  water  bodies  with  any  dilution  are  required  to  implement  advanced 
treatment;  

 “high ambition”: advanced treatment at all plants above 10,000 p.e. and with dilution 
of 100 or less; 

”medium option”: advanced treatment at all plants above 100,000 p.e. irrespective of 
dilution,  and  between  10,000  and  100,000  p.e.  only  when  justified  by  the 
environmental risks caused by the toxicity of the effluents, which we expect to be the 
case when the dilution is 10 or less. For scenario modelling purposes, we assume that 
risks occur in 70% of the cases when effluents are discharged with a dilution of 10 or 
less, excluding discharges to seawater. 

Table  A4.  3  shows  a  comparison  of  indicator  L  among  the  4  scenarios,  as  well  as  the 
current and baseline scenarios, for all Member States and the EU. Table A4.4 shows the 
corresponding costs of advanced treatment.  

The results of this scenario analysis suffer from the uncertainty in the calculation of the 
toxicity emission factors discussed above, while costs can be considered uncertain within 
a  factor  of  2.  On  the  other  hand,  the  uncertainty  in  the  difference  among  scenarios  is 
arguably much smaller, although it is not possible to quantify it.  

119  

 
 
 
 
As  all  the  WWTPs  in  Europe  under  a  full  compliance  scenario  have  a  biological 
(secondary or tertiary) treatment process, obviously the value of indicator L normalized 
by  the  value  under  full  compliance  is  approximately  proportional  to  the  following 
quantity:  

L~ 1 - (1 -a)b  

where a is the ratio between the emission factors of advanced treatment and of biological 
(secondary  or  tertiary)  treatment,  and  b  the  fraction  of  the  treated  load  undergoing 
advanced treatment.  

Parameter a is assumed to be about 0.3 (see Table A4. 4) in our assessment, but could be 
in  principle  any  value  between  0,  meaning  that  advanced  treatment  removes  toxic 
emissions  completely,  and  1,  meaning  advanced  treatment  is  not  effective  at  all. 
Measurements at European WWTPs suggest, however, that an advanced treatment may 
reduce toxicity more than we assume in this analysis, meaning the ratio could be lower 
than  the  assumed  value  of  ca.  0.3  (see  Pistocchi  et  al.,  2022a16,  for  a  more  detailed 
discussion). 

120  

 
 
 
 
 
 
Current  

Baseline  

Low ambition 

High ambition 

6,119,085 

2,742,273 

6,108,046 

2,723,002 

 3,546,436  

 1,969,469  

           4,016,808  

           1,295,348  

Preferred 
Option 
 3,438,856  

 1,738,730  

2,414,676 

2,120,715 

 1,192,954  

               818,890  

 1,097,659  

247,404 

247,404 

 128,582  

                 71,756  

 109,705  

2,606,374 

2,592,882 

 1,890,969  

           1,452,995  

 1,782,165  

32,754,448 

32,722,942 

 21,240,721  

         17,977,985  

 19,424,388  

3,434,246 

3,427,488 

 2,059,544  

           1,160,506  

 1,803,292  

467,417 

467,092 

 224,967  

               179,905  

 218,287  

3,169,802 

3,169,656 

 1,429,615  

           1,036,919  

 1,299,737  

19,548,256 

18,865,567 

 9,962,682  

           7,227,673  

 8,784,926  

1,558,348 

1,542,112 

 970,737  

               708,047  

 859,729  

21,239,621 

21,212,684 

 13,736,729  

         12,803,272  

 13,025,377  

1,259,648 

831,086 

 655,425  

               501,687  

 583,036  

3,621,328 

3,507,410 

 2,188,519  

           2,074,575  

 1,786,917  

1,564,034 

1,528,949 

 807,688  

               656,659  

 780,328  

23,550,204 

22,136,548 

 14,511,265  

         10,524,659  

 12,991,187  

835,613 

189,550 

459,302 

233,874 

835,021 

187,892 

455,703 

233,874 

 451,115  

               346,437  

 415,460  

 146,144  

                 85,375  

 118,943  

 291,351  

               226,829  

 279,275  

 68,377  

                 96,973  

 68,377  

5,750,272 

5,745,852 

 3,317,420  

           2,071,206  

 2,717,265  

11,492,932 

11,277,713 

 7,154,561  

           5,588,834  

 6,231,897  

4,117,119 

3,741,518 

 2,151,928  

           1,577,466  

 1,993,711  

4,388,110 

3,758,579 

 2,074,170  

           1,624,079  

 1,883,691  

3,750,202 

3,730,919 

 2,159,454  

           1,798,495  

 1,976,559  

417,493 

392,153 

 297,248  

               279,597  

 293,388  

1,066,615 

1,050,489 

 749,180  

               640,810  

 712,648  

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

158,998,247 

EU 
total 
Table A4. 3– indicator L under the 5  representative scenarios. Values in pe.  

         76,843,786  

154,613,295 

 95,377,249  

 86,415,534  

121  

 
 
 
 
 
  
 
 
Low ambition (€)  High ambition (€) 

AT  
 BE  
 BG  
 CY  
 CZ  
 DE  
 DK  
 EE  
 EL  
 ES  
 FI  
 FR  
 HR  
 HU  
 IE  
 IT  
 LT  
 LU  
 LV  
 MT  
 NL  
 PL  
 PT  
 RO  
 SE  
 SI  
 SK  
 EU  
Table A4. 4– costs of advanced treatment under the 3 representative scenarios. Values in €.   

 46,218,522  
 41,768,823  
 27,658,707  
 4,047,861  
 29,613,650  
 395,431,303  
 61,573,612  
 6,576,343  
 27,840,446  
 233,330,473  
 19,358,750  
 205,704,604  
 11,240,852  
 43,511,578  
 14,036,162  
 284,333,910  
 9,394,797  
 2,930,275  
 4,373,038  
 1,477,121  
 93,937,353  
 148,376,715  
 49,993,994  
 43,627,782  
 44,336,138  
 2,870,358  
 12,018,361  
 1,865,581,530  

 33,210,752  
 11,707,932  
 10,684,777  
 2,221,470  
 9,510,998  
 163,933,461  
 25,743,637  
 4,145,769  
 12,527,860  
 117,778,928  
 8,422,797  
 100,866,076  
 2,593,678  
 17,815,481  
 7,139,764  
 115,125,309  
 5,321,231  
 805,524  
 1,633,313  
 2,101,382  
 42,911,706  
 64,718,529  
 26,269,579  
 24,670,642  
 21,925,166  
 1,697,477  
 5,869,996  
 841,353,236  

Preferred option 
(€) 
 37,634,807  
 21,949,684  
 14,110,021  
 2,527,273  
 14,178,119  
 238,477,441  
 33,680,164  
 4,926,170  
 14,622,260  
 162,112,160  
 13,046,187  
 130,822,544  
 5,292,965  
 33,482,887  
 8,965,060  
 168,242,744  
 6,565,971  
 1,683,707  
 2,510,885  
 2,101,382  
 64,774,361  
 101,748,705  
 31,301,446  
 32,114,988  
 29,257,162  
 1,697,477  
 7,686,018  
 1,185,512,586  

Figure  A4.  1 shows that, for very different  values  of a,  L  changes much  less as per the 
above linear relationship with b, so a large error on a would reflect in a smaller error on 
L. 

122  

 
 
 
 
 
Figure A4. 2–variation of indicator L (represented here as a percentage of the value of L under 
full compliance) to the % of wastewater subject to advanced treatment (b), for values of a from 
0.01  to  0.7  (a  value  a=0.3  (continuous  black  line)  represents  the  assumption  made  in  this 
analysis).   

6.  Detailed analytical methods - Nutrients 
General description of the methods 

In order to appraise the costs and benefits of nutrient removal, we calculate the discharge 
of total N and total P under the various policy scenarios, as:  

𝑚

𝑚

𝑚

𝐷𝑥 =   (1 − 𝜂𝐼𝑥) ∑ 𝜀𝑥,𝑗𝑃𝑗

𝛿𝐼,𝑗 +   (1 − 𝜂𝐼𝐼𝑥) ∑ 𝜀𝑥,𝑗𝑃𝑗

𝛿𝐼𝐼,𝑗 +   (1 − 𝜂𝐼𝐼𝐼𝑥) ∑ 𝜀𝑥,𝑗𝑃𝑗

𝛿𝐼𝐼𝐼,𝑗 

𝑗=1

𝑗=1

𝑗=1

Where: 

- x=N, P,  

- 𝜀𝑥,𝑗 is the emission factor for N or P at the jth WWTP,  

- 𝜂𝐼𝑥, 𝜂𝐼𝐼𝑥, 𝜂𝐼𝐼𝐼𝑥  are the removal efficiencies for N and P at primary, secondary or tertiary 
level of treatment, respectively,  

- Pj the wastewater load treated by the j-th WWTP in PE 

- 𝛿𝐼,𝑗, 𝛿𝐼𝐼,𝑗, 𝛿𝐼𝐼𝐼,𝑗 are Boolean variables equal to 1 if the j-the WWTP provides primary, 
secondary or tertiary treatment, respectively, and 0 otherwise.  

123  

 
 
 
 
 
The  WWTPs  considered  in  the  analysis  are  the  same  described  under  the  previous 
section,  and  were  characterized  on  the  basis  of  the  data  from  the  10th  Implementation 
report  of  the  UWWTD.  The  removal  efficiency  for  N  and  P  is  given  in  A4.1  The 
emission factors for N and P are assumed to vary by country as per Table A4. 5. 

Country 
Austria 
Belgium 
Bulgaria 
Switzerland 
Cyprus 
Czechia 
Germany 
Denmark 
Spain 
Estonia 
Finland 
France 
Greece 
Croatia 
Hungary 
Ireland 
Italy 
Lithuania 
Luxembourg 
Latvia 
Malta 
Netherlands 
Poland 
Portugal 
Romania 
Slovakia 
Slovenia 
Sweden 

N 
(g/year per 
capita) 
4443 
4033 
3399 
3923 
3695 
3581 
4235 
4653 
4345 
4181 
4785 
4432 
4232 
3623 
3511 
4498 
4161 
5066 
4514 
4177 
4596 
4383 
4189 
4596 
4370 
2803 
3966 
4344 

P in excreta 
(g/year per 
capita) 
515 
471 
430 
445 
457 
421 
490 
516 
496 
474 
541 
521 
510 
431 
420 
530 
512 
590 
514 
491 
541 
483 
503 
522 
541 
339 
481 
484 

P in detergents 
(g/year per 
capita) 
95 
82 
100 
11 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
60 
100 
95 
100 
100 
82.1 
100 
100 
100 
100 
100 
100 

Table A4. 5 – Emission factors for N and P assumed in this study.  

The  policy  options  entail  the  upgrading  of  certain  plants  from  secondary  to  tertiary 
treatment.  We assume the corresponding costs to equal  the difference between  costs of 
new  tertiary  and  secondary  plants,  plus  50%  of  the  costs  of  a  new  secondary  plant  to 
account for the potentially significant infrastructural overhaul. The costs of upgrade are 
likely 
described  with 
overestimated and provides a “worst case” bound to the overall costs. In the calculation, 
we assume a lifetime of the investment of 30 years, and a discount rate of 2.5%. 

the  FEASIBLE  expenditure  functions19,20.  This  cost 

is 

Under some policy options, the removal efficiency of N and P is increased above current 
standards, from 75% to 85% for N and from 85% to 90% for P. In both cases, we assume 

124  

 
 
 
 
the additional costs to be 10% of the annualized cost of a tertiary treatment plant (capital 
repayment,  operation  and  management),  the  latter  evaluated  using  the  abovementioned 
FEASIBLE model expenditure functions.  

The  changes  in  GHG  emissions  under  the  various  policy  options  have  been  evaluated 
using  the  approach  discussed  in  a  dedicated  section  below.  All  calculations  are 
implemented in MS Excel © as discussed in detail in Pistocchi et al., 202224.   

For  the  quantification  of  the  benefits,  we  have  assumed  a  shadow  price  of  GHG 
emissions  of  100  €/t  CO2e,  and  a  shadow  price  of  1  kg  of  N  or  P  removed  from  the 
effluents equal to 20 and 30 €, respectively24.   

How the method has been applied in the impact assessment?  

The  approach  has  been  broadly  discussed  with  experts  involved  in  the  development  of 
supporting scientific work24, and presented and discussed at conferences and workshops 
during the preparation of this IA. The approach has been designed specifically to provide 
a simple and transparent quantification of the policy options.  

7.  Detailed analytical methods - Stormwater overflows (SWO) 
For the modelling of SWO, we developed and applied an urban-scale hydrological model 
simulating  combined  sewer  flows  using  an  input  time  series  of  precipitation  at  the 
resolution of 3 hours.  The model is described in detail in Quaranta et al., 2022a27, and 
was  developed  by  the  JRC  in  the  form  of  an  Excel  ©  workbook.  The  model  itself  is 
available  as  supplementary  electronic  material  with  the  cited  paper.  It  was  developed 
with  the  contribution  of  various  European  experts,  initially  convened  at  a  technical 
workshop  organized  by  the  JRC  in  2019.  Some  of  the  contributing  experts  were  also 
involved  in  the  verification  and  calibration  of  the  model  as  well  as  the  analysis  of 
scenarios as described in details in Quaranta et al., 2022b28.  

The model is applied to describe a unit-area (1 hectare) urban hydrological response unit 
(HRU)  of  impervious  ground  connected  to  a  combined  sewer  receiving  the  wastewater 
generated by a population equal to the average population density of an urban area. The 
lumped,  conceptual  hydrological  model  has  the  analytical  structure  of  a  cascade  of  3 
linear reservoir models with 6 parameters reflecting the rate constant of the reservoir and 
the  volume  filling  threshold  triggering  an  overflow  (see  Quaranta  et  al.,  2022a27,  for 
details).  

The  model  has  been  applied  to  671  HRUs  each  with  the  precipitation  time  series  and 
population density of one of the 671 functional urban areas (FUA) of Europe, as detailed 
in Quaranta et al., 2022a. The parameters of the model were assigned in order to reflect a 
realistic “average” condition of European combined sewer networks, and were found to 
yield  an  acceptably  realistic  description  of  the  initial  situation  in  a  specific  model 
verification exercise (see Quaranta et al., 2022a27, for details).  

Both  SWO  volume,  and  the  volume  of  dry-weather  wastewater  flow  (DWF)  released 
with the SWO, computed for a 1 ha urban HRU for each FUA were then multiplied by 
the impervious area of the FUA and summed by EU member state. The resulting sums 
were multiplied, for each country, by the % of  population  assumed to  be serviced with 
combined sewers in each country, and by a correction factor representing the ratio of the 
total  impervious  urban  area  in  a  country,  divided  by  the  total  impervious  area  of  the 
FUAs in the country (see Table A4. 7).  

125  

 
 
 
 
The model parameters were then changed to simulate the various measures that can be in 
principle  taken  to  reduce  SWO.  The  scenario  chosen  for  reference,  representing  a 
condition  where  SWO  is  managed  so  that  they  meet  the  proposed  standards  (SWO  not 
discharging  more  than  1%  of  the  yearly  dry-weather  wastewater  generated  in  the 
catchment), includes: 

- greening measures in line with the Biodiversity strategy, ensuring an additional surface 
storage volume of 5 mm in combined-sewer urban areas,  combined with  

- constructed wetlands (CW) removing 50% of the pollution of SWO before discharge.  

The  CW  are  sized  in  order  to  detain  SWO  for  1  day  (24  hours).  The  volume  of  the 
required  CW  is  calculated  as  the  average  of  the  50th  and  75th  percentiles  of  the 
cumulative SWO over 24 hours. The total volume required for CW is shown in Table A4. 
8. This is  calculated on the basis of the impervious urban area in the FUA within each 
country,  and  the  percentage  of  this  area  that  is  served  by  CS.  In  this  case,  we  do  not 
correct for the ratio of the total impervious urban area in a country, divided by the total 
impervious  area  of  the  FUAs  in  the  country.  This  accounts  for  the  potential  of 
inexpensive solutions, particularly in less densely populated zones. Inexpensive solutions 
include  the  buffering  of  overflows  in  marginal  land,  effectively  avoiding  most  of  the 
discharge  directly  to  water  bodies,  as  well  as  the  simple  disconnection  of  stormwater 
drainage from sewers by allowing runoff dispersion directly on land.  

The cost of a CW is estimated from an investment cost of 500 Euro/m3, a discount rate 
of 2.5%, a lifetime of 30 years, and an operation and maintenance cost (O&M) of 1% per 
year. The costs of urban greening are not included in the assessment, as they pertain to 
other specific initiatives and deliver benefits much beyond SWO control.  

The various policy options considered in this assessment differ for the size threshold of 
agglomerations for which SWO management is required. The cost of CW, as well as the 
avoided  volumes  of  overflow  and  of  DWF  in  overflow,  are  computed  under  the 
assumption that SWO management applies to all agglomerations, and then multiplied by 
the population in agglomerations subject to measures as a fraction of the total population. 
Information  on  the  factors  used  for  the  calculation  are  provided  in  Table  A4.  8. 
Particularly,  the  policy  options  shown  in  Table  3  in  Section  6.1  of  this  assessment  are 
evaluated considering the population in agglomerations above 100,000 PE (option 1), the 
population above 100,000 PE and 30% of that between 10,000 and 100,000 PE (option 
2),  and  the  sum  of  population  above  100,000  PE  and  between  10,000  and  100,000  PE 
(option 3).  

The  impacts  and  benefits  of  the  policy  options  considered  in  the  IA  were  evaluated  by 
multiplying  the  results  obtained  for  each  EU  Member  State,  by  the  percentage  of  the 
population  equivalents  covered  with  different  thresholds  of  agglomeration  size  (10  and 
100 thousand PE) as for the costs. Impacts are meant here as the reduction of pollutant 
loads discharged through overflows.  

To this end, we convert the volumes of overflow assuming that 1 PE corresponds to 73 
m3/year (200 l/day) of DWF, 60 g BOD/day, 11.18 g N/day and 1.68 g P/day. Runoff in 
overflows  is  converted  to  PE  assuming  the  concentrations  shown  in  Table  A4.  6,  or 
equivalently  considering  the  volumes  of  overflow  as  volumes  of  sewage  subject  to  a 
treatment with a given removal efficiency, as shown in the table. 

126  

 
 
 
 
Pollutant  

BOD 

N  

P 

Toxicity(*) 

Concentration 
mg/L  

7.77 

2 

0.27 

0.50 

Equivalent 
removal 
efficiency  
97% 

96% 

97% 

50% 

Table  A4.  6  –  assumed  concentrations  in  runoff,  and  corresponding  removal 
efficiency  that  would  make  treated  sewage  equivalent  to  runoff.  (*)  Toxicity 
(dimensionless) of runoff is assumed to be 50% of that of untreated sewage.  

For the quantification of the benefits, we have assumed a shadow price of avoided BOD 
emissions of 50 €/t, and a shadow price of 1 kg of avoided N or P equal to 20 and 30 €, 
respectively24.   

Additional benefits not included in the above monetization are those from the removal of 
micro-pollutants and micro-plastics, as well as those related to the reduction of fish die-
offs and impairment of the water bodies as a consequence of reduced pollution episodes. 
Johnson and Geisendorf, 202271 quantify the willingness  to  pay  (WTP) for the latter in 
about  100  Euro/person/year  for  the  case  of  Berlin.  For  a  given  policy  option,  we 
extrapolate  this  WTP  by  multiplying,  for  each  country,  the  total  number  of  population 
equivalents in the agglomerations of the size range affected by the policy (Table A.4.8) 
by  the  assumed  %  of  agglomerations  implementing  specific  measures  for  SWO 
reduction, and the assumed % of urban areas served by combined sewer networks (Table 
A.4.7) and by the WTP of 100 Euro/PE/year. This represents a likely upper limit to the 
benefits  expected  from  SWO  management.  In  order  to  avoid  overestimations  of  the 
benefits, we assume for Europe a WTP equal to 10% of the one in Berlin, on average.   

71 https://www.sciencedirect.com/science/article/pii/S0301479722000810?via%3Dihub# 

127  

 
 
 
 
 
    
 
                                                           
 
EU 
Member 
State 
AT 

Population served 
by combined sewers 
28.0% 

Correction factor (Total to 
FUA impervious area) 
2.00 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

92.3% 

0.0% 

100.0% 

0.0% 

46.1% 

50.0% 

50.0% 

39.0% 

13.0% 

17.5% 

32.0% 

59.0% 

32.5% 

24.0% 

70.0% 

50.0% 

90.0% 

50.0% 

100.0% 

73.0% 

92.0% 

34.0% 

0.0% 

12.0% 

59.0% 

7.5% 

1.99 

2.12 

1.77 

1.80 

1.49 

1.70 

2.07 

2.38 

2.26 

2.52 

1.83 

2.83 

2.24 

2.10 

2.34 

2.62 

1.00 

3.03 

1.12 

1.59 

2.00 

2.41 

3.03 

2.47 

3.01 

3.00 

Table A4. 7– EU Member State factors used for the calculation of SWO  

128  

 
 
 
 
 
 
Overflow 
volume 
Mm3/y, 
current 
conditions  

Volume 
of DWF 
in 
overflows  
Mm3/y, 
current 
conditions 

Reduction 
of DWF 
in 
overflows 
with 
measures, 
Mm3/y  

Reduction 
of 
overflow 
with 
measures, 
Mm3/y 

Volume of 
CW 
required 
for 
overflow 
treatment 
(m3) 

PE in 
agglo 10-
100 k PE 

PE in 
agglo > 
100 k PE 

PE in 
agglomerations, 
total  

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

59 

259 

0 

27 

0 

773 

104 

8 

63 

92 

27 

841 

86 

42 

34 

1287 

15 

42 

6 

12 

135 

414 

164 

0 

22 

57 

2 

27 

0 

2 

0 

35 

11 

1 

4 

8 

3 

68 

6 

4 

3 

90 

2 

4 

1 

1 

6 

43 

11 

0 

2 

4 

0.48 

6.57 

0.00 

0.58 

0.00 

7.76 

2.63 

0.24 

1.26 

1.88 

0.71 

11.57 

55.78 

0.00 

6.08 

0.00 

133.53 

21.85 

1.80 

14.88 

19.84 

6.12 

21.61 

233.24 

1.31 

1.09 

0.92 

15.80 

9.68 

8.38 

23.66 

290.12 

0.49 

0.83 

0.14 

0.38 

2.17 

11.03 

3.07 

0.00 

0.65 

0.66 

3.77 

7.70 

1.10 

4.09 

35.23 

91.69 

41.28 

0.00 

5.55 

8.49 

571,255 

7,417,950  11,493,783 

20,670,206 

2,717,920  3,854,900  4,287,600 

9,231,350 

- 

2,481,677  4,043,148 

7,448,278 

597,602 

381,000 

400,000 

849,500 

- 

4,152,849  3,258,497 

9,348,994 

6,525,214  48,938,729  53,011,623 

112,009,321 

1,055,605  4,906,031  5,452,145 

11,598,945 

101,507 

504,117 

923,961 

1,589,716 

1,446,670  19,425,222  39,135,381 

65,207,923 

2,056,473  2,083,050  2,386,500 

5,057,300 

309,888 

26,750,168  35,178,994 

72,482,923 

10,797,463  2,845,037  7,270,546 

11,021,837 

1,063,079  2,532,958  1,661,154 

4,999,712 

785,497 

4,982,145  6,833,741 

13,588,976 

297,335 

1,439,948  3,146,478 

5,080,615 

20,141,349  30,696,516  37,108,985 

77,187,042 

223,036 

946,880 

1,796,720 

2,905,700 

373,767 

259,190 

231,359 

637,438 

99,210 

706,183 

673,670 

1,611,113 

310,741 

52,313 

736,726 

789,039 

2,234,155  7,349,318  11,623,761 

19,444,506 

6,314,024  13,903,757  20,035,549 

38,542,418 

2,334,196  3,902,270  6,959,400 

12,250,540 

- 

5,105,297  8,431,853 

16,169,845 

272,739 

4,114,260  7,148,200 

12,517,265 

611,116 

502,032 

436,270 

1,462,223 

SK 
Table A4. 8– factors used for the calculation of SWO. DWF = dry weather flow.   

1.05 

0.11 

6 

1 

87,887 

1,904,850  1,255,500 

4,088,385 

8.  Detailed analytical methods - Small agglomerations  
Small  agglomerations  are  not  covered  by  the  current  scope  of  the  UWWTD,  and 
systematic  data  are  not  available  at  European  scale  concerning  agglomerations  below 
2000  PE.  Hence,  a  key  issue  with  the  assessment  of  policy  options  concerning  small 
agglomerations  is  the  estimation  of  the  number  of  agglomerations  and  cumulative 
population  living  therein.  This  assessment  is  based  on  a  model  simulation  of 
agglomerations smaller than 2000 PE, as presented in Pistocchi, 202272.  

72 Supporting report 10 in Annex 10  

129  

 
 
 
 
 
 
                                                           
The  simulation  is  based  on  the  spatial  distribution  of  population  available  for  Europe 
according to  the  Global  Human Settlements  Layer (GHSL)73, and compares favourably 
with  information  available  on  small  agglomerations  in  the  different  MS  gathered  in  a 
study in support to the IA74.  The simulation suffers from an overestimation of population 
living  in  small  agglomerations  as  discussed  in  Pistocchi,  2022.  In  order  to  correct  this 
bias, we considered the average between the simulation and a previous estimate used in 
the GREEN model75.   

The latter was based on the difference between the population of each member state, and 
the  population  corresponding  to  the  population  equivalents  reported  for  agglomerations 
above  2000  p.e.  under  the  UWWTD,  and  appears  to  be  underestimating.  The  two 
estimates  differ  by  a  factor  of  about  3,  and  their  average  is  still  compatible  the 
information  gathered in  the different  MS. The loads from  small agglomerations remain 
affected by a significant uncertainty, close to a factor 2, as further discussed in Pistocchi, 
2022.  The  dataset  of  simulated  agglomerations  is  publicly  available  as  supplementary 
electronic material of the cited paper.  

Table  A4.  9  summarizes  the  assumed  population  in  the  various  EU  MS  living  in 
agglomerations  between  50  and  2000  PE.  This  is  assumed  to  undergo  a  given  level  of 
treatment,  based  on  the  information  gathered  in  each  MS  concerning  the  current 
practice35.  

Based  on  the  estimated  population  in  small  agglomerations,  we  compute  the  costs  and 
pollution  reduction  due  to  improving  the  treatment  level  from  current  conditions  to 
policy  scenario  standards.  The  policy  options  considered  entail  enforcement  of  a 
secondary (biological) treatment for all agglomerations above a certain population size. 
When a MS has a level of treatment already equivalent to secondary or more stringent, 
the policy does not cause any change. Also, agglomerations below the size assumed for 
the policy scenario do not change their assumed current level of treatment. When small 
agglomerations have a level of treatment less stringent than secondary, we represent the 
cost of upgrade to a secondary system as (Pistocchi, 2022):  

Annualized Cost = 218.36 * P-0.37 (€/PE/year) 

This  cost  corresponds  to  assuming  that  (1)  agglomerations  are  initially  equipped  with 
septic  tanks,  (2)  a  sewer  network  does  not  exist  in  the  agglomeration;  and  (3)  the 
secondary treatment plant is a constructed wetland.   

The reduction of pollution achieved by expanding the scope of the UWWTD to smaller 
agglomerations is evaluated as the difference between loads emitted under baseline and 
under  policy  scenario  conditions.  To  this  end,  we  assume  the  emission  factors  for 
conventional pollutants as shown in Table A4. 1. For the quantification of the benefits, we 
have assumed a shadow price of avoided BOD emissions of 50 €/t, and a shadow price of 
1 kg of avoided N or P equal to 20 and 30 €, respectively24.   

73 https://ghsl.jrc.ec.europa.eu/  
74 Annex 10, report 1  
75 Vigiak, O., Grizzetti, B., Zanni, M., Dorati, C., Bouraoui, F., Aloe, A., Pistocchi A., Estimation of domestic and 
industrial waste emissions to European waters in the 2010s, EUR 29451 EN, Publications Office of the European 
Union, Luxembourg, 2018, ISBN 978-92-79-97297-3 , doi:10.2760/08152, JRC113729. 

130  

 
 
 
 
 
 
                                                           
Untreated 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
- 
8,419,068 
- 
- 
702,693 
- 
- 
9,121,761 

 AT  
 BE  
 BG  
 CY  
 CZ  
 DE  
 DK  
 EE  
 EL  
 ES  
 FI  
 FR  
 HR  
 HU  
 IE  
 IT  
 LT  
 LU  
 LV  
 MT  
 NL  
 PL  
 PT  
 RO  
 SE  
 SI  
 SK  
 total  
Table A4. 9– Assumed load of wastewater (PE) from agglomerations smaller than 2000 PE, at 
different levels of treatment. Estimations are based on detailed results from Annex 5  

More stringent 
- 
924,016 
- 
- 
- 
- 
489,605 
- 
- 
- 
722,561 
- 
- 
- 
- 
- 
- 
- 
- 
- 
572,870 
- 
- 
- 
- 
- 
- 
2,709,052 

Mechanical 
- 
- 
1,008,806 
- 
- 
- 
- 
- 
- 
2,256,118 
- 
- 
511,990 
- 
- 
3,468,576 
655,136 
- 
- 
- 
- 
- 
- 
2,799,874 
- 
626,849 
- 
11,327,349 

Biological 
1,009,259 
- 
- 
247,538 
2,120,496 
6,923,236 
- 
99,698 
1,341,030 
- 
- 
9,667,829 
- 
1,042,439 
575,845 
- 
- 
64,439 
460,709 
2,180 
- 
- 
959,706 
- 
- 
- 
1,616,210 
26,130,613 

Total 
1,009,259 
924,016 
1,008,806 
247,538 
2,120,496 
6,923,236 
489,605 
99,698 
1,341,030 
2,256,118 
722,561 
9,667,829 
511,990 
1,042,439 
575,845 
3,468,576 
655,136 
64,439 
460,709 
2,180 
572,870 
8,419,068 
959,706 
2,799,874 
702,693 
626,849 
1,616,210 
49,288,776 

131  

 
 
 
 
 
 
 
9.  Detailed analytical methods - Greenhouse gas emissions 
General description of the method 

Greenhouse gas (GHG) emissions are computed for each wastewater treatment plant on 
the  basis  of  its  size  and  level  of  treatment,  using  the  emission  factors  described  in 
Parravicini et al., 202276, based on a specific improvement of the IPCC 2019 Guidelines 
to  account  for  the  state  of  current  knowledge  of  GHG  emissions  from  the  wastewater 
sector.  The emissions of all WWTPs were summed by country and at EU scale, to yield 
the  total  emissions  from  the  sector.  Under  an  energy  neutrality  scenario,  we  assume 
electricity  to  come  at  zero  emissions.  For  a  climate-neutral  scenario  we  assume  the 
emissions corresponding to the average of two scenarios, namely:  

-  A scenario with systematic implementation of simultaneous aerobic stabilization 

of the sludge, yielding the lowest possible N2O emissions;  

-  A scenario with  systematic implementation  of anaerobic digestion with  delivery 
of  bio-methane  to  the  gas  grid,  thus  displacing  fossil  methane,  yielding  low 
emissions of CH4 and credits from the displaced fossil fuel.  

The model calculations are all implemented in an Excel © workbook, provided for open 
access  as  supplementary  electronic  material  to  Parravicini  et  al.,  202237.  The  JRC 
developed  the  model  with  leading  European  experts  after  thorough  consultation  of 
additional experts from the sector (in government, academia and industry).   

Although the validation of GHG emissions from the wastewater sector is problematic for 
various reasons  also  due to  the difficulty of measurements and their  generalization, the 
results  of  the  calculation  were  found  in  line  with  the  current  literature,  as  discussed  in 
Parravicini et al., 202237. 

10. Micro-plastics 
Under  all  policy  options,  we  quantify  the  change  in  microplastics  emissions  with 
effluents  and  runoff.  For  runoff,  we  assume  an  amount  of  Tire  wear  particles  (TWP) 
generated  in  Europe  equal  to  1,327,000  t/a  according  to  Wagner  et  al.  (2018).  Of  this 
amount,  we  assume  10%  (132,700  t/a)  ends  up  in  urban  runoff,  uniformly  distributed 
across the EU. With 57.7 billion m3/a of urban runoff (Pistocchi et al., 2019), this results 
in an average concentration of 2.3 mg/L TWP. Plastics in WWTP effluents are assumed 
to equal 560 mg/PE/a according to Simon et al. (2018), as the result of a 95% removal in 
WWTPs. This is not the average removal rate of a WWTP, but a representative value for 
the plants Simon et al., (2018) refer to. Hence in untreated sewage the plastics amount to 
560 /  (1-0.95) = 11200 mg/PE/a. The concentration  in  untreated sewage, assuming 200 
l/PE/day  of  sewage,  is  11200  /  (365*0.2)  mg/m3  =  0.157  mg/L.  when  comparing  the 
various  policy  options,  we  consider  a  removal  efficiency  of  microplastics  in  WWTPs 
equal  to  70%  for  primary  treatment,  85%  for  secondary,  90%  for  tertiary  and  99%  for 
advanced treatment.  

Additional details can be found in Obermaier and Pistocchi, 202277 . 

76 Supporting report 9 in Annex 10. 
77 See Annex 10, report 15 

132  

 
 
 
 
                                                           
11. Definition of the reference maximum technical feasibility scenario  
In order to appraise the impacts of the preferred policy options, we compare them with 
the scenario corresponding to the “maximum technical feasibility” option for each 
specific problem. This is summarized in the following table.  

Specific problem  

Storm water overflows (SWO) 

Maximum technical feasibility 
scenario  
Doubling of the removal under 
the preferred option  

Micro-pollutants 

Nutrients 

Small agglomerations  

All plants above 5,000 p.e. 
discharging with a dilution ratio 
of 100 or less are treated 
All plants above 2000 p.e. are 
required to remove N and P 
with higher efficiency than 
current  
All agglomerations above 100 
p.e. are required to have at least 
a secondary treatment 

Reasoning  

Result of combining the most extensive 
preventive measure with the treatment 
of overflows as in the preferred option.  

An upper limit of advanced treatment 
requirements.  

The maximum removal that can be 
achieved before regulating smaller 
agglomerations as well.  

Assumed upper limit of regulation.  

12.  References of supporting reports - see Annex 10 documents 8 to 18.  

133  

 
 
 
 
 
 
ANNEX 5: SUMMARY OF MEMBER STATE SITUATION 

On top of the core consultation activities, Member States were consulted on the basis of 
pre-filled  overviews.  MS  had  the  opportunity  to  comment,  provide  their  feedback  and 
validate  on  these  pre-filled  overviews.  The  Member  State  overviews  were  filled  in, 
consolidated  with  the  inputs  from  the  EPR  Feasibility  study,  reviewed  by  the 
Commission  and  sent  to  the  Member  States  for  the  opportunity  to  complete  the 
information,  comment  on  the  content  and  any  assumptions  made,  notably  for  the 
modelling.  

Member States have had 4-6 weeks to verify their national information presented in the 
overview and to challenge the assumptions made by the project team on likely impacts of 
possible change to the legislative framework for their country.  

The EC has received 25 Member State responses to the overviews.  

Member State overviews cover all areas of intervention considered as part of the impact 
assessment.  The  overviews  are  mostly  descriptive  and  present  the  current  practices  in 
Member States, including where practices go beyond the requirements of the UWWTD. 
It also included the main assumptions used in the context of the modelling.  

Section 

Summary 

Storm water 
overflows and 
urban runoff 

Smaller 
agglomerations 

  Urban runoff management differs significantly between Member 

States.  

  12 of 21 reporting Member States have mainly separate sewers 

with the minority combined. However, there is a wide variety of 
combinations among Member States and differences between 
older and newer urban areas. 

  Several Member States report that new additional urban areas are 

serviced by separate sewers.   

  2 Member States reported a reference to treatment requirements 

for ‘first rain’.  

  Several Member States reported treatment of overflows and 
several Member States also reported explicit dilution rates. 

  5 reported the use of Integrated Management Plans.  

  Evidence collected from 21 Member State authorities suggests 

that there may be more than 85.000 agglomerations below 2.000 
p.e. across these countries.  

  For 15 Member States, the majority of small agglomerations are 

 

connected to an urban wastewater treatment plant.  
In 2 Member States, individual and appropriate systems are most 
commonly used to manage urban wastewater from small 
agglomerations. 

Individual or 
other 
Appropriate 
Systems 

  26 Member States have national legislation on IAS in place but 
there are a few that do not have specific regulatory frameworks 
for IAS either for smaller agglomerations or for all 
agglomerations independent of size. 

  17 Member States reported that the connection to the public 

134  

 
 
 
 
Sensitive areas 
(in combination 
with nutrient 
removal) 

Micro-
pollutants  

Industrial 
discharges 

sewer system is mandatory where available (sometimes 
facilitated by financial incentives).  

  The predominant types of IAS installed are cesspools and septic 
tanks. At least 9 Member States do not report the use of IAS in 
agglomerations < 2000 p.e. (not required by the UWWTD).  
  At least 14 Member States require a permit for the use of IAS.  
  At least 13 Member States do not centrally record use of IAS 

through a national database.   

  The inspection and monitoring schemes across the Member 

States vary to a great extent. 

  Only 9 Member States apply stricter measures than those set in 

the Directive. 

  10 countries apply more stringent standards for certain pollutants 
or for smaller agglomerations or include new agglomerations size 
range.  

  The majority of Member States have a nitrification requirement.  
  The majority of the Member States have designated part of their 
territories as sensitive areas; only 11 Member States go beyond 
UWWTD by classifying their whole territory as Sensitive Areas. 
Drivers mentioned include orthophosphate/phosphorous 
compound levels, vulnerability, the status of water bodies 
according to WFD, eutrophication, poor status of receiving 
waters. 

  A specific national definition for eutrophication often does not 

exist and only 3 Member States use a methodology aligned with 
the Nitrates Directive. 

  13 Member States do not apply a nutrient balance calculation. 
  Only 9 Member States are entirely designated as Nitrate 

Vulnerable Zones (NVZ). 

  5 Member States identified a link when designating NVZs with 

sensitive zones under the UWWTD. 

  Each Member State has different approaches to the monitoring 

and treatment of micro-pollutants, and the predicted future uptake 
of 4th stage treatment technologies varies widely between 
Member States. 

  11 Member States have mandatory pollutant-specific treatment 
level for UWWTPs receiving industrial discharges (from either 
IED installations or SMEs). 

  9 Member States have specific provisions in their legislation 

regarding the specification for pre-treatment of wastewater from 
industrial sites as mandatory. 

  The setting of limit values for industrial wastewater discharges to 

UWWTP is performed differentially based on prescriptive 
provisions in regulations or permits or based on operational 
agreements. 

135  

 
 
 
 
Energy 
efficiency, 
generation and 
climate 
neutrality 

 

In 10 Member States, no legislation in relation to energy 
efficiency requirements is in place.  

  There is legislation and/or guidance, to various extents, in place 

in 8 Member States.  

  There are 9 Member States with a requirement to carry out 

 

energy audits in UWWTPs.  
In most cases, Member States have taken no action in relation to 
the energy efficiency of UWWTPs (only 2 Member States have 
concrete legislative measures in place). 

Greenhouse gas 
emissions, 
including 
methane 

  12 Member States do not have any information available on 

average emissions of greenhouse gases.   

  Another 8 Member States have information available on average 

emissions of greenhouse gases. 

Circular 
economy (sludge 
reuse) 

  Sewage sludge is not used in agriculture in several Member 

States due to concerns related to contaminants. Alternatives such 
as incineration (with or without energy recovery) are often used. 

  Pre-treatment of industrial discharges is mandated in several 

Member States.  

  Assessment of micro-pollutants is being undertaken by several 

Member States. 

  Of the information that was identified, 4th stage treatment is not 
planned to be widely used in the near future by Member States. 

Monitoring and 
Reporting 

  All Member States have adopted sampling frequencies that 

comply with the requirements of the UWWTD. 

  6 Member States have not set any other sampling frequencies 

than those set in the Directive. 

  11 Member States have set additional frequencies for sampling of 

UWWTPs below 2.000 p.e. 

  5 Member States have set frequencies taking into other 

parameters than the size of the WWTPs (e.g., sampling per 
parameters). 

  The sampling process and sampling parameters vary between 
Member States and are covered within Appendix B in detail. 
  12 Member States have indicated that continuous monitoring is a 
common practice in wastewater treatment plants (and an addition 
5 Member States have continuous monitoring the largest 
WWTPs) and that data from continuous monitoring is available 
to water authorities. 

  Member States show some diversity on the monitoring of TOC. 
  All Member States (who responded to this topic) indicated that 

exact measurements, including concentrations are made available 
to authorities. 
In many instances, the monitoring requirements are detailed in 
the permit of the UWWTPs. 

 

Wastewater 

  A Europe-wide Umbrella Study was conducted to monitor the 

136  

 
 
 
 
surveillance 

presence of the SARS-CoV-2 virus (that causes COVID-19) in 
the population. On 17/03/2021, the EU Commission published a 
Recommendation on a common approach to establish a 
systematic surveillance of SARS-CoV-2 and its variants in 
wastewaters in the EU.  

  The Umbrella Study involved 17 Member States. 

Information to 
the public 

  Requirements for public consultation and participation are in 

place in 5 Member States and are primarily in place in relation to 
EIAs for new UWWTPs.  

  Additional requirements in relation to reporting (made available 

to the public) is in place in 13 Member States. 

Access to 
sanitation 

  The specific recognition of the right to sanitation is only subject 

to the national legislation of 1 Member State. 

  Other countries have made attempts to different extents. 

Access to justice    Of the Member States for whom information was identified, 2 
Member States identified specific legal provisions for access to 
justice and 2 Member States identified their transposition of the 
Aarhus convention. Furthermore, several Member States 
identified that no additional requirements on access to justice 
beyond the UWWTD are applied. 

Source: Wood report Section 3 p.21-22, see Annex 10, report 1  

137  

 
 
 
 
 
 
ANNEX 6:  ASSESSING COMPLIANCE  

To assess compliance, the following examples of organisation of the data to be gathered 
can be considered:  

I. 

Agglomerations  

II. 

Population of each municipality/agglomeration  

III. 

Individual and other Appropriate Systems  

a.  Data on exceedances 

b.  Type of IAS applied 

c.  Measures in place to ensure inspection  

IV. 

Storm water overflows and urban runoff 

a.  Existence of integrated management plan  

b.  % of system that is combined / separate 

c.  Results of data monitored notably for what relates to the % of pollutants 

releases compared to dry weather conditions or equivalent data   

d.  Information on separate sewer discharges 

V. 

Access to sanitation 

a.  Identification of the vulnerable/marginalised people and measures taken to 

ensure/improve  access to sanitation   

b.  Measures taken to improve access to sanitation in the cities  

VI. 

Treatment Plants 

a.  Volume of urban wastewater treated by each treatment plan and design 

capacity 

b.  Parametric values of effluent at UWWTPs discharge point 

i.  Data on concentrations  

ii.  Data on percentage of reduction (for secondary, tertiary with stricter P 
& N thresholds and fourth treatment for micro-pollutant removal) 

iii.  Data on toxicity (e.g. from bio-assays)78 

78 As included in Commission Implementing Decision (EU) 2016/902) establishing best available 
techniques (BAT) conclusions for common wastewater and waste gas treatment/ management systems in 

138  

 
 
 
 
                                                           
 
iv.  Other parametric values (e.g. Environmental Quality Standards 

Directive parameters)  

b.  Energy use and reduction over time; and energy production 

i.  If an audit system is in place and date of last audit  

ii.  Baseline of last 3 years of energy use in kWh/p.e79  

iii.  % reduction over X years achieved. 

c.  Greenhouse gas emissions and reduction of emissions over time 

i.  Report on performance indicators (see IPCC 2006, 2019) 

the chemical sector: https://eur-lex.europa.eu/legal-
content/EN/TXT/PDF/?uri=CELEX:32016D0902&from=EN 
79 Baseline should account for the energy consumption for new treatment technologies applied to reduce 
micro-pollutants in treated urban wastewater 

139  

 
 
 
 
 
 
                                                                                                                                                                            
ANNEX 7:  ADDITIONAL DETAILED INFORMATION    

Collection - Article 3 

Secondary - Article 4  More stringent  - Article 5 

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LV 

LT 

LU 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

0% 

0% 

5% 

15% 

0% 

0% 

0% 

0% 

0% 

0% 

0% 

0% 

11% 

3% 

0% 

1% 

0% 

0% 

0% 

0% 

0% 

0% 

0% 

36% 

0% 

1% 

1% 

0% 

0% 

18% 

15% 

0% 

0% 

0% 

0% 

4% 

9% 

1% 

6% 

67% 

12% 

50% 

12% 

0% 

0% 

0% 

98% 

0% 

1% 

6% 

66% 

1% 

26% 

1% 

0% 

1% 

20% 

16% 

21% 

0% 

1% 

0% 

1% 

16% 

2% 

6% 

89% 

10% 

75% 

6% 

0% 

0% 

1% 

100% 

0% 

4% 

15% 

59% 

3% 

36% 

2% 

Table A7.1: Distance to target per MS in 2018, source: Annex 10, report 7 

140  

 
 
 
 
 
 
BOD 

Nitrogen 

Phosphorus 

E. coli 

Micro-
pollutants 

SWO 

9.497.956 

9.497.956 

9.497.956 

9.497.956 

9.497.956 

Urban runoff 

3.021.652 

4.178.561 

4.655.970 

11.669.055 

58.345.277 

Non Compliant IAS 

9.761.177 

8.437.746 

8.437.746 

10.328.361 

8.860.309 

Compliant IAS 

653.509 

4.901.318 

4.356.727 

1.089.182 

3.428.287 

Small Agglo 

16.461.634 

30.143.614 

28.044.961 

18.639.594 

25.634.454 

Non compliant load 
from wastewater 
plants 

Remaining compliant 
load treated in 
wastewater plants 

4.420.871 

3.601.479 

11.541.423 

5.272.255 

2.312.323 

22.332.023 

130.366.051 

82.065.999 

14.614.358 

156.048.652 

Total remaining load 

66.148.823 

191.126.725  148.600.784 

71.110.762 

264.127.257 

Table A7.2: Remaining loads sent to the environment   - source JRC, See annex 4  

Treated load 
(pe)  

Treated 
load (%) 

Cumulati
ve load 
(%)  

Number 
of 
facilities  

Number 
of 
facilities(
%)  

Cumulati
ve 
number 
(%)  

<1000 

24.644.388 

4,32% 

100,00% 

30.354 

41,51% 

100,00% 

1001-2000 

24.644.388 

4,32% 

95,68% 

19.138 

26,17% 

58,49% 

2001-10.000 

56.691.407 

9,94% 

91,36% 

16.102 

22,02% 

32,31% 

10.001-100.000 

199.793.943 

35,02% 

81,42% 

6.610 

9,04% 

10,29% 

100.001-1.000.000 

165.897.806 

29,08% 

46,41% 

864 

1,18% 

1,25% 

> 1.000.000 

98.865.557 

17,33% 

17,33% 

53 

0,07% 

0,07% 

 Total  

570.537.489 

100% 

73.121 

100% 

Table A7. 3: Treated load, number of treatment plants per category size (source – JRC 2021)  

141  

 
 
 
 
 
 
   
  
 
 
 
 
Agglomeration 

Treated load 
(pe) 

Treated 
load (%) 

Cumulati
ve load 
(%) 

Number 
of 
agglomera
tions 

Number 
of 
agglomera
tions(%) 

Cumulati
ve 
number 
tions (%) 

< 1000 

24.644.388 

4,15% 

100,00% 

30.354 

42,63% 

100,00% 

1001 - 2000 

24.644.388 

4,15% 

95,85% 

19.138 

26,88% 

57,37% 

2001 - 10.000 

63.626.959 

10,72% 

91,70% 

13.954 

19,60% 

30,49% 

10.001 - 100.000 

202.455.997 

34,10% 

80,98% 

6.840 

9,61% 

10,89% 

100.001 – 1M 

216.413.317 

36,45% 

46,88% 

> 1.000.001 

61.891.051 

10,43% 

10,43% 

876 

38 

1,23% 

1,28% 

0,05% 

0,05% 

Total  

593.676.100 

100% 

71.200 

100% 

Table A7.4:  Treated load, number of agglomerations (based on MS reports for agglomerations 
above 2.000 p.e. and on JRC below 2.000 – see Annex 10, report 7 and 10)   

142  

 
 
 
 
 
 
 
 
 
 
BOD  

Nitrogen  

Phosphorus 

E. Coli. 

Micro-
pollutants 

982.988 

4.841.959 

2.591.978 

569.588 

7.269.045 

1.335.367 

3.213.281 

2.219.618 

1.569.320 

6.932.759 

1.200.409 

2.761.572 

2.186.688 

1.213.787 

2.942.393 

132.994 

378.495 

286.978 

165.853 

699.318 

645.548 

3.136.876 

2.199.997 

533.381 

3.545.495 

6.045.065 

27.373.203 

16.335.408 

4.269.852 

43.559.047 

793.354 

2.876.336 

1.614.096 

636.738 

4.920.322 

109.766 

407.577 

243.584 

82.476 

633.860 

867.769 

3.293.870 

4.409.166 

801.879 

4.897.692 

6.224.028 

24.792.808 

19.527.424 

7.427.139 

24.235.427 

370.575 

1.973.909 

807.885 

504.821 

2.289.153 

5.892.901 

24.048.613 

18.930.021 

6.342.548 

36.055.353 

2.903.371 

4.912.404 

4.567.034 

3.674.225 

5.683.355 

2.139.098 

5.278.430 

4.196.803 

2.249.799 

6.120.729 

554.087 

2.611.671 

2.100.435 

837.615 

2.402.121 

11.698.165 

30.222.485 

27.497.639 

14.944.615 

48.568.544 

556.669 

1.204.833 

889.115 

583.722 

1.626.472 

101.079 

253.551 

180.764 

130.651 

525.712 

149.437 

565.518 

404.267 

149.434 

721.932 

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

50.921 

188.181 

337.330 

42.372 

332.704 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

1.017.682 

4.350.802 

2.417.517 

660.753 

7.470.835 

11.881.413 

19.508.154 

16.023.586 

11.954.366 

26.443.195 

1.791.299 

6.381.166 

5.769.058 

2.638.153 

7.439.871 

6.146.977 

9.379.433 

8.166.039 

6.366.004 

9.683.748 

1.300.473 

3.975.096 

2.060.985 

1.214.548 

4.870.822 

709.482 

1.241.119 

1.110.856 

945.243 

2.201.401 

547.903 

1.955.381 

1.526.514 

601.881 

2.055.954 

Total 

66.148.823 

191.126.725 

148.600.784 

71.110.762 

264.127.257 

Table A7.5: Starting position - remaining total pollution per MS   (p.e. per year)  

143  

 
 
 
 
 
 BOD 

 Nitrogen 

Phosphorus 

E. Coli 

Micro-pollutants 

982.712  

4.776.459  

2.587.832  

546.008  

7.264.004  

1.305.155  

3.124.313  

2.095.212  

1.517.803  

6.903.582  

830.195  

2.718.057  

2.100.757  

875.145  

2.787.322  

119.700  

365.201  

273.684  

152.559  

686.024  

512.585  

3.049.183  

1.961.037  

387.226  

3.444.735  

6.030.528  

27.313.726  

15.632.341  

4.246.324  

43.564.031  

792.313  

2.864.136  

1.596.993  

632.346  

4.919.383  

100.572  

398.545  

232.128  

73.444  

624.827  

726.442  

3.197.615  

4.310.627  

641.453  

4.787.093  

4.463.935  

23.347.879  

16.544.830  

5.502.645  

22.850.725  

348.909  

1.959.779  

779.625  

481.271  

2.272.917  

5.860.178  

23.875.125  

17.034.481  

6.280.093  

36.042.001  

956.981  

3.553.503  

3.208.133  

1.476.053  

4.136.872  

817.798  

4.190.002  

3.104.480  

820.218  

4.966.007  

428.232  

2.514.022  

2.010.150  

691.295  

2.303.401  

9.140.615  

28.943.614  

24.393.328  

12.102.546  

47.165.347  

520.846  

1.180.826  

855.909  

543.711  

1.598.889  

98.239  

242.233  

166.729  

124.799  

523.383  

126.268  

628.487  

403.443  

133.166  

756.559  

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

50.921  

188.181  

337.330  

42.372  

332.704  

NL 

PL 

PT 

RO 

SE 

SI 

SK 

1.015.153  

4.295.523  

2.312.854  

640.852  

7.466.581  

11.413.974  

18.760.109  

13.940.937  

11.403.368  

26.111.479  

1.229.235  

5.992.623  

5.299.321  

2.003.827  

7.001.877  

1.911.616  

4.903.262  

3.275.387  

1.900.529  

5.625.198  

1.300.473  

3.900.146  

2.060.985  

1.187.566  

4.865.055  

584.185  

1.044.244  

856.609  

787.973  

2.090.006  

299.015  

1.760.707  

1.246.470  

315.554  

1.864.623  

Total 

51.966.775  

179.087.499  

128.621.614  

55.510.146  

252.954.625  

Table A7.6: Full implementation - remaining total pollution per MS (p.e. per year)  

144  

 
 
 
 
 
 
PE (BOD) 

PE (N) 

PE (P) 

PE (coli.) 

PE (tox) 

             973.984  

       3.224.208  

     1.665.054  

    27.261  

       4.528.605  

          1.209.235  

       2.438.914  

     1.652.186  

     1.167.253  

       5.538.284  

             661.450  

       1.768.241  

     1.184.964  

        382.876  

       1.632.070  

             111.726  

          289.076  

        222.510  

        115.771  

          511.584  

             512.585  

       2.531.274  

     1.640.524  

        200.779  

       2.634.019  

          5.928.573  

     19.502.774  

   10.887.951  

     1.287.057  

     29.611.873  

             759.590  

       1.978.244  

     1.054.752  

        278.307  

       3.167.187  

               97.388  

          266.098  

        150.665  

          22.483  

          364.488  

             705.892  

       2.267.789  

     2.403.258  

        281.297  

       2.814.172  

          4.121.344  

     11.910.806  

     5.191.524  

     1.070.721  

     12.377.161  

             336.300  

       1.250.743  

        453.216  

        212.271  

       1.539.761  

          5.607.007  

     17.070.757  

   11.198.073  

     3.528.963  

     26.663.693  

             865.910  

       2.928.612  

     2.461.106  

     1.157.893  

       3.671.634  

             800.686  

       2.990.945  

     1.959.827  

        369.689  

       3.175.191  

             415.898  

       1.285.630  

        637.899  

        235.380  

       1.503.459  

          8.112.554  

     19.592.485  

   14.875.127  

     7.663.326  

     35.339.851  

             461.895  

          915.395  

        682.866  

        394.405  

       1.109.306  

               91.646  

          197.602  

        137.537  

        101.350  

          426.589  

             123.037  

          522.994  

        338.644  

          91.812  

          568.102  

               48.621  

          106.644  

        150.587  

          10.280  

          156.396  

             988.001  

       2.758.223  

     1.401.863  

          49.112  

       4.270.128  

          9.745.509  

     15.090.633  

   11.243.121  

     8.786.994  

     19.368.415  

          1.175.483  

       3.124.260  

     1.917.666  

        901.137  

       4.960.512  

          1.395.384  

       3.591.525  

     2.354.828  

        968.387  

       3.345.888  

          1.115.151  

       2.671.245  

     1.323.520  

        603.183  

       2.941.002  

             510.509  

          911.032  

        751.431  

        667.741  

       1.856.563  

             296.257  

       1.538.638  

     1.101.687  

        232.432  

       1.514.533  

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

      EU 27                   47.171.616  

   122.724.787  

   79.042.386  

   30.753.638  

   175.590.463 

Table A7.7: Preferred option - remaining total pollution per MS by 2040 (p.e. per year)  

145  

 
 
 
 
  
 
AT 

BE 

BG 

CY 

CZ 

DK 

EE 

EL 

ES 

FI 

IE 

IT 

LT 

LU 

LV 

SWO 

Advanced 
treatment 

N removal  

P removal   

Small 
agglomerations 

3.560.329,31 

37.634.807 

32.379.268 

5.291.899 

16.330.626,78 

21.949.684 

12.952.199 

2.116.851 

- 

- 

- 

14.110.021 

29.355.506 

6.456.473 

8.219.939 

- 

- 

- 

- 

- 

- 

- 

- 

- 

- 

- 

- 

- 

- 

3.742.600,63 

2.527.273 

1.514.832 

259.727 

- 

14.178.119 

11.435.666 

1.869.953 

DE 

40.457.861,96 

238.477.441 

167.387.373 

27.364.710 

6.421.552,56 

33.680.164 

17.792.156 

2.908.121 

621.158,85 

4.926.170 

2.692.551 

440.598 

8.850.101,31 

14.622.260 

20.164.361 

16.206.301 

12.380.600,66 

162.112.160 

433.509.361 

79.209.160 

20.951.645 

1.803.587,45 

13.046.187 

25.749.799 

1.249.958 

FR 

67.504.427,91 

130.822.544 

199.545.499 

41.598.903 

HR 

6.074.831,94 

5.292.965 

27.095.418 

6.384.738 

3.767.257 

HU 

4.652.621,94 

33.482.887 

39.995.041 

8.904.487 

1.828.429,24 

8.965.060 

54.094.724 

11.983.135 

120.526.543,74 

168.242.744 

310.661.745 

76.238.048 

40.257.269 

1.434.560,68 

6.565.971 

4.657.565 

761.559 

1.615.957 

1.959.380,80 

1.683.707 

821.998 

134.039 

578.808,45 

2.510.885 

2.216.124 

362.289 

MT 

2.116.764,86 

2.101.382 

1.818.724 

1.632.185 

NL 

14.850.045,72 

64.774.361 

31.792.349 

5.192.741 

PL 

PT 

RO 

SE 

SI 

SK 

37.874.231,11 

101.748.705 

56.357.670 

9.214.379 

27.484.957 

14.097.828,85 

31.301.446 

124.114.881 

29.627.744 

- 

- 

32.114.988 

20.130.685 

3.291.664 

31.165.876 

1.671.644,53 

29.257.162 

30.846.067 

3.175.212 

5.464.910 

2.671.321,25 

1.697.477 

1.868.410 

322.912 

1.478.466 

462.787,78 

7.686.018 

4.880.057 

797.844 

- 

EU
27             

372.472.648 

1.185.512.586 

1.665.830.029 

342.995.630 

140.406.278 

Table A7.8: Detailed costs of the preferred option per Member State (€ per year by 2040)  

146  

 
 
 
 
  
              
Total benefits (€/year)  

Total costs (€/year) 

174.914.995 

78.866.303 

94.494.053 

53.349.360 

100.232.620 

58.141.939 

10.082.786 

8.044.433 

56.105.349 

27.483.738 

953.191.567 

473.687.386 

106.556.866 

60.801.994 

15.582.780 

8.680.477 

260.765.336 

59.843.024 

1.150.729.864 

708.162.927 

166.668.941 

41.849.532 

678.512.609 

439.471.374 

74.757.636 

48.615.210 

141.983.549 

87.035.037 

137.425.378 

76.871.348 

1.157.375.180 

715.926.350 

31.024.455 

15.035.613 

6.040.250 

13.156.919 

12.747.036 

4.599.125 

5.668.106 

7.669.056 

197.125.498 

116.609.496 

475.052.545 

232.679.943 

325.829.876 

199.141.900 

132.592.302 

86.703.213 

129.501.116 

70.414.996 

15.757.529 

8.038.587 

24.638.474 

13.826.707 

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

 EU 27  

      6.642.845.627 

3.707.217.171 

Table A7.9: Total costs and benefits of the preferred option per MS by 2040  

147  

 
 
 
 
 
 
Total cost 
€/year/inhab 

Total benefits 
€/year/inhab 

5,20 

3,49 

4,16 

7,29 

1,50 

3,68 

7,36 

4,50 

3,71 

5,80 

2,91 

3,56 

5,33 

4,83 

4,55 

6,84 

3,71 

5,95 

1,82 

11,34 

4,85 

4,66 

7,29 

3,47 

3,81 

2,93 

1,64 

19,58 

8,17 

14,49 

11,25 

5,24 

11,46 

18,25 

11,72 

24,41 

24,28 

30,12 

10,06 

18,52 

14,59 

27,45 

19,53 

11,10 

9,52 

6,95 

24,70 

11,28 

12,55 

31,64 

6,91 

12,48 

7,47 

4,51 

AT 

BE 

BG 

CY 

CZ 

DE 

DK 

EE 

EL 

ES 

FI 

FR 

HR 

HU 

IE 

IT 

LT 

LU 

LV 

MT 

NL 

PL 

PT 

RO 

SE 

SI 

SK 

Table A7.10: 2040 costs and benefits of the preferred option per inhabitant    

148  

 
 
 
 
  
 
ANNEX 8: MAIN RELATIONS BETWEEN ONGOING INITIATIVES AND THE PRESENT INITIATIVE  

Initiative  

Brief description of the initiative  

Evaluation 
of the 
Sewage 
Sludge 
Directive 

Revised 
Industrial 
Emission 
Directive 

Revised 
Energy 
Efficiency 
Directive 
(EED) and 
Renewable 
Energy 
Directive 
(RED)   
Climate 
Regulation, 
Effort 
sharing 
regulation 
and 'Fit for 

This Directive regulates the use of sludge in agriculture and 
includes limit values (mainly for heavy metals) when sewage 
sludge is used in agriculture. The Directive is under evaluation 
before deciding on its possible revision.  

The Industrial Emission Directive (IED) regulates water and air 
emissions from large industrial facilities.  

The proposal for a revised EED requires MS to further reduce their 
energy consumption by 9% by 2030 (compared to 2020). Energy 
audits are imposed for enterprises consuming large amounts of 
energy. The exemplarity of the public sector is highlighted and a 
specific objective is included in the EED for the public sector 
(1,7% reduction per year).   The proposal for a revised Renewable 
Energy Directive set a binding target of 40 % for the overall share 
of energy from renewable sources in the EU's gross final 
consumption of energy in 2030.  
The Climate Regulation includes a legally binding objective of 
climate neutrality for the EU by 2050.  The Efforts Sharing 
Regulation (ESR) request MS to reduce GHG emissions from the 
sectors not covered by the EU Emission Trading Scheme - 
including wastewater treatment. Binding national emission 
reduction targets are included in the ESR.   The 'Fit for 55' 

Potential interactions and added value of the preferred option  
Measures aiming at better controlling pollution at source notably for 
non-domestic pollution will contribute to improve the quality of the 
sludge making it more suitable for agriculture. Actions to better capture 
and treat SWOs and urban run-off are expected to allow capturing more 
micro-plastics and increase their presence in sludge.  Moving towards 
energy neutrality will only happen if more sludge is digested (production 
of biogas).  
Most of the large facilities are located outside the cities and are not 
connected to the urban collection system. When they are connected, the 
ongoing revision of the IED will contribute to better control wastewater 
emissions from large industrial facilities notably for what relates to non-
domestic pollution. Reversely, actions aiming at better controlling the 
incoming waters in the wastewater treatment plants will help reducing 
possible emissions from IED facilities connected to the public network.   
Moving towards energy neutrality for the wastewater sector by 2040 will 
directly contribute to reach the objectives of the RED and the EED as 
combination of measures will be necessary to meet energy neutrality 
(more energy efficiency, production of bio-gas and installation of 
renewables). The optimal combination of measures needs to be defined 
at each plant level based on in depth energy audits - which are not 
required for wastewater treatment plants under the EED.  Fixing a 
specific energy neutrality objective for the sector will help capturing the 
specific potential from this sector while promoting the development of 
optimal solutions at local level.  

Sections in the IA were 
interactions are 
described  
The potential 
consequences on sludge 
management of the 
proposed measures are 
identified in the IA 
(sections 1, 7.1, 5.2.8 
and 6.6). 

The interactions between 
the IED and the 
proposed revised 
UWWTD are identified 
in sections 1, 2.1.1.7, 
5.2.6 and 7.1. 

The interactions with the 
RED and EED as well as 
the necessity of a 
specific target of energy 
neutrality for the sector 
is explained in section 
2.1.2.2 (problem 
definition), 5.1 
(baseline), 5.2.7 and 7.1 

Moving towards energy neutrality by 2040 of the wastewater sector will 
directly contribute to reduce its GHG emissions (around 46,45% of the 
'avoidable' emissions of the sector). It will help to achieve the objectives 
of the ESR, the Climate regulation and the "Fit for 55" package (62,5% 
reduction compared to 1990 levels).  

The impacts of energy 
neutrality on GHG 
emissions are discussed 
in section 5.1, 5.2.7 and 
7.1  

149 

 
55' package   package includes different measures ailing at reaching a reduction 
of GHG emissions of 55% by 2030 (compared to the 1990 levels).  

The plan aims at rapidly reduce dependence on Russian fossil fuels 
and fast forward the green transition 

RePowerEU    

Proposal for 
Nature 
Restoration 
Regulation 
(NRR)  

The proposal of NRR aims at ensuring that there is an increase in 
the total national area of urban green space in cities and towns and 
suburbs of at least 3 % of the total area of cities and towns and 
suburbs in 2021, by 2040, and at least 5 % by 2050.  

Initiative on 
micro-
plastics  

The Micro-plastics initiative is expected to reduce non-intentional 
micro-plastics emissions from some sources such as the textile, 
tyre or plastic pellets. 

The preferred option through the energy neutrality objective will directly 
contribute to the objectives of the REPowerEU plan: more biogas and 
more renewables are expected to be produced while at the same time 
efforts will be achieved to reduce energy use. The REPower plan will on 
the other side help achieving the energy  neutrality objective for the 
sector notably by promoting the ‘to-go areas’ which could include 
wastewater treatment plants and  offering new funding opportunities for 
renewables and energy savings.  
The NRR will directly contribute to increase the green areas in the cities 
and therefore the capacities of urban soils to absorb rain water. In case 
heavy rains, less ‘clean’ rain water will be mixed to polluted waters in 
the urban collecting systems and less untreated water will be sent to the 
environment. The precise effects on water absorption of Nature 
Restoration targets will depend on the very local circumstances, but both 
legislation will act in a synergetic way. The NRR was taken into account 
in the modelling (see annex 4).  
With the planned initiative and in the mid-term, less emissions of micro-
plastics from these sectors could expected in urban wastewaters. But 
even if all possible measures are taken to reduce emissions at source, 
there will always be residual emissions. Micro-plastics are well captured 
in wastewater treatment plants (between 80% up to 99% when tertiary 
treatment is in place).  The proposed set of measures (notably measures 
to better manage urban run-off and SWOs, to impose more tertiary 
treatment for N/P but also to improve IAS and cover smaller 
agglomerations from 1.000 p.e.) will improve the abilities of capturing 
more micro-plastics in the collecting and treatment system. This will 
complement the envisaged measures under the micro-plastic initiative.  

The potential influence 
of the REPowerEU plan 
is discussed in section 
5.1 (Baseline scenario)) 
and 7.1 (preferred 
option).  

The influence of the 
Nature restoration 
targets on the SWOs and 
urban run-off 
management is detailed 
in sections 1, 7.1 and  
6.1.   

The expected 
interactions between the 
initiative on micro-
plastics and the review 
of the UWWTD are 
discussed in sections 1, 
2.1.1.6, and 7.1.  

150 

 
 
ANNEX 9: ACTORS INVOLVED IN AN EPR SCHEME AND THEIR RESPECTIVE ROLES  

The roles and responsibilities of the main actors involved in the possible EPR scheme is 
displayed  in  Figure  9.1  below  and  summarised  in  the  following  Table  (main  source: 
report 2 in Annex 10).  

Figure  9.1:    Roles,  responsibilities  and  relationship  between  the  different  actors 
involved in the EPR scheme (source: report 2, Annex 10).  

Main actors 

Main role and responsibilities of the actors 

European Union 

  The EU in its Directive will define minimum objectives, the 
scope and common principles for the EPR scheme to be 
complied by Member States, in line with the generic 
principles of an EPR defined in the Waste Framework 
Directive (including modulation on fees, full cost coverage, 
transparency).   

Member States  

  Member States would be responsible mainly for overseeing 

the detailed and proper implementation of EPR 
(transposition  compliance)   

  More specifically, MS should ensure that: 

  a reporting system is in place to collect data on products 
placed on the market and on wastewater treatment; 
  PROs have the financial and organisational means to 
meet the EPR obligations (procedure to recognise the 
PRO’s) and proper self-control mechanisms (regular 

151 

 
 
 
independent audits for financial management and quality 
of data collected and reported); 

  Fee modulation is applied by the PRO’s; 

  MS will also put in place a control system to ensure that all 
importers/producers are fulfilling their obligations by being 
member of a PRO’s.   

Producers/Importers   

They will have to adhere (have a contract) with  PRO’s, 
declare what they are placing on the EU market and pay 
fees to PRO’s depending on the quantities and toxicity of 
the products they place on the market.  

Producer 
Responsibility 
Organisations 
(PRO’s)  

Wastewater 
operators   

  They will take decisions on cost allocation (either product 
cost increase or reduce profit margins) and on product 
composition (less toxic if possible).  

  PRO’s will implement the financial responsibility  for the 

treatment of micro-pollutants for their members;   

  PRO’s will collect statistics on products placed on the EU 
market by their members, and collect their financial 
contributions according to fees to be established by the 
PRO’s;   

  The funds collected will be used to finance additional 

treatment (4th treatment) via contracts to be established with 
wastewater operators while respecting the deadlines and the 
objectives fixed in the Directive.  

  They will have to progressively install additional treatment 
for micro-pollutants in line with the deadlines included in 
the Directive and with the financial support of the PRO’s 
(contract to be established).  

  They will report on the performances met to PRO’s and 

competent authorities.  

Auditing Companies     External control by independent auditing companies will 
concern the quality of the reported statistics on products 
placed on the EU market and on financial streams;   
  Results of the audits should be made available to MS 

competent authorities.    

Table A9: Summary of the roles and responsibilities of the main actors involved in the 
possible EPR scheme. 

152 

 
 
 
 
 
 
 
ANNEX 10: LITERATURE REFERENCES   

Main reports used for this impact assessment:  

1.  WOOD (2021) Study to support the Impact Assessment of the UWWTD 
2.  Bio Innovation Service (2021) Feasibility of an EPR system for micro-pollutants 
3.  EC/Eunomia, (2018) Investigating options for reducing releases in the aquatic 

environment of micro-plastics emitted by (but not Intentionally added in) products: 
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4.  OECD (2021) Building a methodology to assess the benefits of a revision of urban 

wastewater regulation in the European Union 

5.  OECD (2020) Financing Water Supply, Sanitation and Flood Protection: Challenges 

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6.  OECD (forthcoming 2022) Transparency and the performance of wastewater 

collection and treatment services 

7.  European Commission (2020) 10th implementation report of the UWWTD, 10th 
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