Norwegian Water—Selected Summaries

Norwegian Water Selected

SUMMARIES of water reports 2008 – 2013

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About Norwegian Water Norwegian Water is a special interest organisation representing Norway’s water industry. It acts on behalf of the members, which are municipalities, companies owned by municipalities, municipal operational assistance organisations and some private water works. Norwegian Water in total represents 360 municipalities, with 95 % of the population.

There are also nearly 100 affiliated members like consultants, producers, suppliers and institutions for research and education.

Norwegian Water serves both as a special interest organisation and a competence building organisation for the members. The organisation works within the vision of “clean water – our future” with emphasis on: • Strengthening the reputation and customer relation for the water sector • Lobbying for better framework conditions, by representing the water sector in contact with politicians and authorities on regulations etc.

• Strengthening the education system and the recruitment to the water sector • Development and transfer of competence, through: • the Norwegian Water project system • courses and training • meetings and conferences • information systems, such as webpages, a magazine, newsletters etc.

The Norwegian Water project system Projects at a value of 10 million NOK (1.25 million EUR) are performed each year through the project system in Norwegian Water. The project system is financed by the members as a voluntary additional fee.

The projects are proposed, approved and partly governed by the members, while specialists in the secretariat have the role as project managers. The best consultants in the marked are hired to perform the projects and write the reports and guidelines from the project system.

Most of the projects are presented as a Norwegian Water report. The reports can be purchased from www.norskvann.no, and may be downloaded for free for the members taking part in the project system.

The project system has so far produced 200 reports and guidelines for the members.

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Contents Page 5

Report B17 – 2013 Investment needs in the water and wastewater sector

Page 6

Report 164 – 2008 UV disinfection guidance manual

Page 7

Report 171 – 2009 Experiences with leak detection and control

Page 8

Report 177 – 2010 Drinking water quality and new challenges – Status and problems overview

Page 9

Report 188 – 2012 Enhanced coagulation process operation guidance

Page 10

Report 190 – 2012 Adaptation to climate change in municipal plans in th water and wastewater sector

Page 11

Report 194 – 2012 Optimal energy design of wastewater plants

Page 12

Report 196 – 2013 Guideline for condition analysies and renewal of water and wastewater networks

Page 13

Report 197 – 2013 Wastewater Systems – Risk assessment on the environment

Page 14

Report 198 – 2013 Micropollutants in Norwegian sewage sludge – Results from a 2013/2013 investigation

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Investment needs in the water and wastewater sector Report B17 – 2013

Norsk Va nn

Author:

Keywords:

Rappor t B17

2013

Investe ringsbe hov i vannog avlø pssekto ren

Norsk Van n BA, Van Tlf: 62 gsvegen 55 30 30 143, 232 www.nor E-post: 1 Hamar post@no skvann.n rskvann o .no

idetrykk.no

Number of pages:

Jonny Ødegård, Maria Persson and Tom Baade-Mathiensen, Norconsult Water and wastewater facilities, replacement cost, investment needs 56

Norsk Va for vann nn er en ikke-k skal bid og avløpsse ommersiell int kto ra eresse organisa VA-sekto til å oppfylle ren (VA-sekto sjo visjonen ren kunnska ren funksjon om ren ). Organisas n elle ram psutvikl jon t vann me ing og ved å sik en kunnska vilkår og leg ge til ret re psdelin Norsk g. te for Va VA-selsk nn eies av no rsk aper, ko noen pri mmun e kommuner, enes dri vate an kommun ca 360 delsvan ftsassis alt eide ko tanser nverk.

Virksomh mmuner me for VA Norsk Vann og d ov eten fin fra me ansieres er 95 % av lan representer dlemm er i hoveds de ene. ak gjenn ts innbyggere . om konti Norsk ngenter Va styre sa nn styres av eierne mmensa gjennom tt av rep årsmøtet resentan og av et ter fra eierne.

I Norsk Va prosjekte nns prosjekts yst r for ca . 6 mill. em gjennom føres hv kroner Det er ert år praktiske vannog avløp og aktuelle spørsmå som utr l innen edes for Deltake rne for eslår pro og får full tilg sjekte ang til alle res r, styrer gjenn ultater omføring en

Norwegian water and wastewater facilities will meet several large challenges in the years to come. Insufficient maintenance, as well as predictions in population growth, climate change, and urbanization, has recently led to further challenges. An essential question lies, therefore, in the cost of a satisfactory water and wastewater system.

The report defines the replacement cost and estimated investment needs of Norwegian water and wastewater facilities, with the work completed in three steps: – The replacement cost of the existing system – The investment needs to upgrade the existing system to the required standard in 2012 – The investment needs to extend and improve the system from the required standard in 2012 to the expected situation and requirements in 2030 The replacement cost of the water and wastewater facilities is based on statistical data and evaluated at 1 053 billion NOK, or equivalent to 40 per cent of the Norwegian gross national product.

Approximately 62 per cent is connected to public-owned facilities and 38 per cent to private-owned facilities, such as house-owners’ pipes, wells, and treatment plants.

As the existing system does not satisfy today’s requirements, it is necessary to evaluate the costs to fulfil these demands.

There are many approaches that can be used to estimate this cost: the most reliable method is the cost reported from the municipalities that includes an estimated increase in the network cost to approximately 200 billion NOK (124 billion NOK for public-owned facilities and 76 billion NOK for private-owned facilities).

Finally, the report evaluates the investment requirements to fulfil the needs in 2030. There are many uncertainties, including impacts from expected climate changes, future population growth, and future public demands.

Joint investment demands are estimated at 290 billion NOK (186 billion NOK for public-owned facilities and 104 billion NOK for private-owned facilities).

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UV disinfection guidance manual Report 164 – 2008

Norsk Va nn

Rappor t 164

Author:

Keywords:

Number of pages:

Bjørnar Eikebrokk Christen RÌstad Lars J. Hem and Karl Olav Gjerstad Water supply, disinfection, UV, hygienic barrier, design, operation 154

The application of UV disinfection systems is rapidly growing throughout the world. The main reasons for this trend are two-fold: 1) the documented ability of UV systems to inactivate chlorine resistant pathogenic microorganisms, including parasites like Cryptosporidium and Giardia, and 2) the small or negligible formation of disinfection by-products.

In Norway, the number of facilities using UV disinfection (approximately 800) has equalled the number of facilities using chlorination for many years. While small facilities were the predominant UV users before, now even the largest facilities have changed to using UV. Due to a number of UV facilities experiencing severe design and operation challenges, the Norwegian and Swedish Water Works Associations initiated a joint project in 2007 aimed at providing an updated UV disinfection guidance manual.

Based on feedback from existing facilities, it was past time for this project to be realized. The main objective of the manual was to support waterworks that planned, designed, and operated UV disinfection systems. The research institute, SINTEF (Trondheim, Norway), was contracted to prepare the guidance report.

2008

Veiledn ing for UV-des av drikk infeksjo evann n

The guidance report presents and discusses major design and operation issues, such as identification of design flow rates and water quality characteristics, source water quality variations and effects of up-stream water treatment processes, variable power supply quality, fouling of quartz sleeves and UV intensity sensors, dose-monitoring strategies, back-up power supply systems, alternative approaches for the assessment of UV disinfection barrier efficiency and stability. The report also suggests alternative contract forms and specific challenges related to early systems without biodosimetrically approved UV reactors.

Some UV system challenges are to a degree country specific, for instance the instability in power supply (e.g., power interruptions, voltage sags) that causes a high number of starts and stops and significant UV reactor down-time in many places. Typical as well for many UV installations in Norway and Sweden are the significant effects of natural organic matter and extended use of enhanced coagulation processes (where coagulant residuals may act as UV absorbers) and sleeve and sensor foulants. The extent of this problem is not only dependent upon the water source and the raw water characteristics, but also on the extent and methods of up-stream water treatment.

Given the significant design and operation challenges revealed, the report hopes that the joint project and this UV guidance report will lead not only to improvements in design, operation, and control of UV disinfection systems, but also to a general increase in the competence level among the involved stakeholders.

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Experiences with leak detection and control Report 171 – 2009

Norsk Va nn

Rappor t 171

Author: Co-authors: Keywords: Number of pages:

Asle Flatin Asbjørn Unhjem Kristin Jenssen Sola Water supply, water distribution system, leak detection 43

There is an increased focus on leak detection in water distribution systems in Norway. Water loss from municipal pipelines ranges from 14 per cent to 40 per cent of total water supply production. The lost water results in higher costs for water production (treatment) and distribution, including the pumping of water. The high leakage rate also represents a hygienic challenge as pollution can enter if there is no water pressure in the supply system.

As part of this project, a questionnaire was distributed to Norwegian municipalities. Fifteen waterworks responded and their experiences are included in this report.

The report presents recommendations linked to: • Zoning of the water distribution system To monitor the minimum night flow, the water distribution network is divided into metering zones.

The flow of water through each zone is monitored by the use of flow transmitters.

• Organization of the operational works The leak detection activities are organized in teams of one or two operators. Each team operates a car that is equipped with leak detection equipment and a computer with digitized maps of the water distribution system.

2009

Erfaring

er med lekkasje

kontroll

• IWA methods International Waterworks Association (IWA) methods are used to calculate the amount of water leakage, water balance, and minimum night flow.

• Leak detection The most common methods in Norway for performing leak detection are: – Correlation: Two sensors attached to the pipeline record the sound of the leakage, which is amplified and transmitted to the correlator. Hydrophones are used on plastic pipelines.

– Sounding: Direct sounding in manholes and ground microphones on terrain are used.

• Water supply system design Preparation for leak detection must be made when designing the water supply system.

• Reduction in water pressure Reduction in water pressure leads to a reduction in water loss.

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Drinking water quality and new challenges – Status and problems overview Report 177 – 2010 Author:

Keywords:

Number of pages:

Norsk Va nn

Norsk Va for vann nn er en ikke-k skal bid og avløpsse ommersiell int kto ra eresse organisa VA-sekto til å oppfylle ren (VA-sekto sjo visjonen ren kunnsk ren funksjon om ren ). Organisas n ell apsutvi kling og e rammevilkå t vann ved å jonen r sik kunnsk apsdeli og legge til ret re Norsk ng. te for Vann eie s av no VA-selsk rsk aper, ko noen pri mmun e kommuner, en vate an kommun ca 360 delsvan es driftsassis alt eide ko tanser nverk.

Virksom mmuner me for VA Norsk Vann rep og d over heten 95 fi fra me dlemm nansieres i ho % av lande resenterer ene. ts vedsak gjennom innbyggere. konting Norsk Va enter styre sa nn styres av eierne mmensa gjenn tt av rep resentan om årsmøtet og av et ter fra eierne.

I Norsk Va prosjekte nns prosjekts ys r for ca . 6 mill. tem gjennom føres hv kroner Det er ert år praktisk e vannog avløp og aktuelle spørsmå som utr l innen edes for Deltake rne for eslår pro og får full tilg sjekte ang til alle res r, styrer gjenn ultater omføring en

Svein Forberg Liane Stein W. Østerhus Bjørnar Eikebrokk and Mathias H. Kleppen Water supply, climate change, pollution and pathogens, drinking water quality, drinking water treatment, scenarios, research and development 62

Rappor t 177

2010

Drikkev an utfordri nskvalitet og nger – kommen problem oversikt de og stat us

idetrykk.no

Norsk Van n BA, Van Tlf: 62 gsvegen 55 30 30 143, 232 www.nor E-post: 1 Hamar post@no skvann.n rskvann o .no

The project’s objective was to prepare Norwegian waterworks for tomorrow’s challenges in terms of potentially harmful contaminants in drinking water. The report describes the expected trends and assesses the ability of today’s water treatment methods to handle the anticipated changes in our water sources. The report also gives recommendations for further work and proposes specific research and development projects.

Projected climate changes will lead to quality changes in our drinking water sources. Climate projections in Norway show a trend in terms of increased rainfall, increased runoff, and more extreme weather events. More frequent episodes of heavy rain and large local variations in rainfall intensity are expected, which will increase the risk for pathogens and other contaminants in drinking water sources. It is expected that an increased amount of organic matter and particles in the water sources will occur as well. Increased colour has already been noticeable in many of our major surface water sources in the past 10 years.

Steady growth in global travel, such as tourism and migration, increases the risk of spreading pathogenic microorganisms.

This unconscious importation of new pathogens, along with the possible increase in temperature and improved living conditions for new pathogens in Norwegian ecosystems, will provide more challenges for the waterworks.

The proportion of people with weakened immune systems is expected to rise, mainly due to the rapidly increasing number of elderly people and people being treated for serious illnesses. This section of the population is particularly dependent on a good hygienic standard for drinking water. More knowledge about risk factors, improved analytical methods, and improved information from extended sampling and water analysis will provide waterworks with further challenges.

Examples include recent

knowledge about mould in drinking water and living conditions for pathogens in the supply network.

Waterworks must prepare for increased information demand from consumers and officials in terms of transparency and documentation of water delivery. Customer demand will increase for good water quality and safe drinking water.

The waterworks will also need to enhance efficient and environmentally sound use of resources, including factors such as energy efficiency, sludge production in water treatment, and by-products in drinking water where chemicals are added.

In recent years, there has been a major improvement in water treatment by most large- and medium-sized waterworks in Norway. Processes such as coagulation filtration, ozone treatment, biofiltration, and membrane filtration have been introduced to reduce colour, remove particles, and improve the hygienic quality and safety of drinking water.

In addition, UV disinfection in several places has either replaced or been added as a supplement to chlorine disinfection.

The report questions whether the chosen design processes are sufficiently suitable to meet the challenges faced by increased organic content and rapid variations in sourced water quality. To maintain production capacity and provide a stable supply of good quality drinking water, many water treatment plants, including recently constructed ones, must be rebuilt or expanded within the next few years. Another option is to seek better sources of drinking water.

The report indicates a need to improve the skills of operational personnel, waterworks administrators, and consultants to understand and deal with future challenges and more complex water treatment processes.

Greater challenges are expected at waterworks that source water from the ground. An increase in iron and manganese content and aggressive CO2 is already noticeable in many places.

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Enhanced coagulation process operation guidance Report 188 – 2012

Norsk V ann

Rappor t 188

Author: Keywords: Number of pages:

Bjørnar Eikebrokk Water, coagulation, operation 155

2012

Veiledn ing for dri koagule ringsan ft av legg

The report covers the operation of enhanced coagulation processes to achieve optimum water quality/safety, safety barrier efficiency, barrier stability, and sustainability/resource efficiency. These are important and relevant issues with regards to operation and operation performance of enhanced coagulation processes, because treatment technology is applied by most large-sized utilities. A significant proportion of the Norwegian population is supplied with coagulated water (approximately two million out of a total population of five million). In addition, coagulation treatment barrier efficiency and barrier stability rely on good operation performance of the treatment process.

challenges and proposed corrective actions. It provides a list of major coagulation and coagulation performance issues where more knowledge and research are needed.

As a supplement to the guidance report on operational issues, a separate coagulation optimization handbook was also published (Norwegian Water Report 189 – 2012).

The handbook contains detailed descriptions of recommended coagulation and filtration optimization procedures, including plans for the mapping of relevant process conditions and online process data and plans for water sampling and analysis.

It is recommended that operators run the optimization experiments while the treatment plant is still in regular production.

The report focuses on operation performance and good operation practices, but also covers issues related to coagulation process design and dimensioning. After initial chapters covering the project background and objectives, including some important terms and general issues within the fields of coagulation and separation/filtration, the report presents and discusses a number of important issues related to coagulation process operation, water quality standards, and coagulation barrier indicators as presented in Norwegian drinking water regulations.

The report also presents assessments on coagulation treatment barrier efficiency and stability, along with a number of experiences and recommendations for good operation practices, including process control options and management of sludge and waste. In addition, the report describes different filter materials and bottoms and presents procedures for inspection and assessment of filters and filter bed conditions. It also describes and quantifies potential effects of climate change on coagulation processes and operation performance, mainly on the basis of a large number of pilot-scale enhanced coagulation experiments.

Finally, the report presents some common operational

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Adaptation to climate change in municipal plans in the water and wastewater sector Report 190 – 2012 Author: Keywords:

Number of pages:

Trond Sekse Norconsult AS Adaptation to climate change, municipal planning, master plan, zoning plan, plan for land use, stormwater, wastewater, drinking water 48

Norsk Va nn

Rappor t 190

2012

Klimati lpa og avlø sningstiltak in p i kom nen va nn munale planer

The climate is changing. In Norway, we can generally expect higher than average temperatures, more rain, and more extreme weather. We must adapt to these expected climate changes by planning for and establishing a more robust infrastructure. Adapting to expected climate changes is a major challenge for many Norwegian municipalities already struggling with the consequences of climate change.

Events in recent years show major challenges associated with the handling of flooding and landslides in waterways, basement flooding, urban flooding, rising sea levels, and sea waves. These challenges are expected to increase in the future due to climate change.

specifically handled within each plan level. In all land-use planning issues related to stormwater management, flooding and sea-level rise must be assessed. To achieve a futureoriented and sustainable management of stormwater, as well as good holistic solutions, the assessments must be implemented in a early phase of the planning process.

Especially because these issues can result in restrictions on land use within the project area. A robust and sustainable plan requires efficient interdisciplinary planning and co-ordination, along with a holistic way of thinking with regards to selected solutions and possible future development. Land-use area also needs to be seen in a larger context.

A future-oriented and sustainable infrastructure demands careful preparation at all levels of planning, such as municipal master plans, sector plans, zoning plans, and building projects.

This guidance should help to achieve better integration of climate change adaptation measures in municipal plans within the stormwater, wastewater, and drinking water sectors.

Zones requiring special consideration (attention zones) can be used in municipal and regulatory plans to focus on areas of danger, conservation, and safety. Such zones can be used regardless of land purpose, as well as across different land-use purposes and other attention zones.

The climate adaptation measures in this report primarily focus on those regarding better and more robust handling of increased climate effects on water supply systems, wastewater systems, stormwater systems, and urban creeks and rivers. This guidance is based on the different levels within municipal planning. A joint checklist for all plan levels has been prepared and enclosed with this report.

The report is primarily aimed at planners within different disciplines, including land-use planners, urban planners, road planners, and landscape architects. The guidance will be available at Klimatilpasning.no. A guide to climate change adaptation, a useful tool for municipalities, will be available as well.

Climate and stormwater issues must be

Planning provisions can be used to indicate further requirements for land purposes and attention zones.

The report includes some examples of provisions that can be relevant in municipal and zoning plans.

The report also contains a checklist for climate adaptation measures in municipal and zoning plans within the stormwater, wastewater, and drinking water sectors. The checklist is helpful for those working with preparation and approval of municipal plans, zoning plans, different types of project plans, and building applications. The checklist can further be helpful in connection with preliminary conferences and meetings as a complementary checklist for relevant issues. In addition, it can be a good starting point for planners to create their own checklists as documentation in the planning process. The list can be customized by adding relevant items and removing irrelevant items.

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Optimal energy design of wastewater plants Report 194 – 2012

Norsk Va nn

Rappor t 194

Author: Keywords:

Number of pages:

Robert Martinez Norconsult Energy-optimized design for wastewater treatment plants, energy monitoring, energy-efficient cleaning processes, energy leading, design handbook for energy use and reuse 57

Energir iktig des ig av avlø psrense n og prosjek tering anlegg

A public and political spotlight on energy use and reuse has also targeted the water and wastewater sector. The potential for energy efficiency is high for the Norwegian water and wastewater sector. Newer, larger plants with even stronger environmental requirements will lead us to more energy use, such as an increased need for blowing machines. To optimize the use of energy, we need to introduce energy leading in all phases, including design, engineering, and operation.

Several countries have already developed checkpoints and handbooks for energy-optimized wastewater treatment plants.

Among them are Sweden, Denmark, Germany, Switzerland, and the United States of America. The report is mostly based on DANVA’s energy reuse campaign and the Swedish VA-Forsk report, Energy Handbook for Wastewater Treatment Plants.

It is also based on Norconsult’s experiences with engineering treatment plants and the municipality of Bergen’s earlier experiences with water and sewage. The checkpoints in the report were tested by Bergen while planning and engineering the renovation of four large treatment plants and the building of a new biogas plant.

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2012

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Guideline for condition analysies and renewal of water and wastewater networks Report 196 – 2013 Author:

Keywords: Number of pages:

Jon Røstum Anette Kveldsvik Desjardins Arve Hansen and Stian Bruaset Water and wastewater networks, renewal 99

196

2013

Veiledn ing i tils ta fornyels e av VA ndskartleggin g og -transp ortsyst emer

Water and wastewater networks are critical infrastructures; the structural condition of these infrastructures, therefore, is important.

The report presents guidelines for asset management of water and wastewater networks with work based on state-of-the-art asset management in combination with practical experience with pipe rehabilitation in Norway.

The asset management of water systems takes into account the following planning levels: – The strategic level defines the direction that the organization wants to go in the long term in relevant aspects to the asset management of infrastructure – The tactical level defines the path in the medium term, and establishes priorities for intervention and possible solutions – At the operational level, the defined path is followed in the short term, and includes the implementation of measures The guideline includes practical examples on how rehabilitation is planned. Each chapter includes recommendations for water and wastewater networks.

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Norsk Va nn

Rappor t

12

Wastewater systems - Risk assessment on the environment Report 197 – 2013 Author:

Keywords: Number of pages:

Norsk Vann

Line Diana Blytt and Elisabeth Lyngstad Aquateam Risk assessment, environment RAV, wastewater systems 61 (66)

RAPPORT

197/20

13

Avløpsanle

Vurderin

gg

g av ris

iko for

ytre mi ljø

ISBN 97882-414-0 ISSN 1504 347-7 -9884v 1

This guideline describes the process for environmental risk assessment and management regarding emissions to the environment from sewage systems and wastewater treatment plants. It is intended as an aid to reduce the consequences of emissions and to mitigate any acute accidental and planned emissions.

The guideline also describes the elevated risk caused by climate change and provides an introduction to the work methodology based on the Norwegian standard, Requirements for risk assessment (NS 5814:2008).

This work flow has three phases: planning, risk analysis, and risk evaluation, including action plans. Risk analysis is based on the Risk Analysis and Vulnerability (RAV) methodology. Environmental risk acceptance criteria are grouped into high, medium, and low risk categories.

By using a risk matrix, risk is quantified by multiplying the probability of an incidence with a number for the consequences to the environment.

challenges to the operation of the wastewater systems are assessed and how planning, systemizing, analysis, and evaluation of the risk of the emissions to the environment can be performed. Vanndal has encountered various challenges that may affect the environment, such as: – Combined sewer systems causing periods with hydraulic overload – Frequent emergency overflow discharges caused by flooded pumping stations – Irregular organic loads in wastewater treatment plants – Odour emissions from sludge treatment – Vulnerable river recipients (source for drinking water down-stream of the discharge point) – Vacant positions in the organization Other methods of analysis can be used besides RAV, especially for more technical system components, such as pumping stations. Risk assessments should be updated periodically to ensure that medium and high risks are managed and new risk areas are investigated.

The guideline describes a process-oriented work methodology for risk assessment by reviewing all the wastewater treatment processes and discharge points. Vanndal is used as an example for a municipality conducting an environmental risk assessment. This gives an idea of how the environmental

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Micropollutants in Norwegian sewage sludge – Results from a 2012/2013 investigation Report 198 – 2013

Norsk Va nn

Rappor t 198

Author:

Keywords:

Number of pages:

Line Diana Blytt Alizada Beslagic Bruskeland Pascale Stang Toxic organics, organic micropollutants, sewage sludge, sampling and analysis, Norwegian wastewater treatment plants 60 (94)

In 2012/2013, an investigation was carried out to analyse the content of organic micropollutants and silver and arsenic in Norwegian sewage sludge. Fifteen municipal wastewater treatment plants took part in this study. From October 2012 to February 2013, five samples of sludge were analysed each month for different micropollutants, grouped as follows: Chemicals analysed since 1996 (some exceptions): polycyclic aromatic hydrocarbons (PAH16), ftalates (DEHP and DBP), nonylphenol and -ethoxylates (NPE), linear alkylbenzene sulphonates (LAS), brominated flame retardants (BFR), bisphenol A, and perfluorinated compounds (PFCs).

2013

Organis ke miljøg – Result ifter i n ater fra or undersø sk avløpsslam kelsen i 2012/1 3

While there are fewer studies to compare the results for the extra chemicals, levels seem to be in line with Norwegian and other Nordic studies. The concentration of siloxanes and organotin in sewage sludge is considerable lower in this study compared to earlier Norwegian and Nordic studies.

No comparison data has been found for methylparaben.

Difenacoum, flocoumafen, and warfarin were not found in any of the sludge samples above the detection limit of 10, 10, and 40 μg/kg TS, respectively.

Extra chemicals: musk compounds (galaxolide and tenolide), triclosan, parabens (methylparaben), siloxanes, arsenic, silver, alkyl phenols, rat poisons (difenacoum, flocoumafen and warfarin), and organotin.

While concentrations of PAH16, ftalates, and NPE are reduced considerably compared with the last investigation performed in 2006/07, LAS has increased by 24 per cent and bisphenol A by 43 per cent (both are median values). Brominated flame retardants and PFCs remain at the same level.

The concentration levels of the micropollutants in sludge have increased for some wastewater treatment plants and decreased for others.

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N O R W E G I A N WAT E R R E P O R T

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Norwegian Water in total represents 360 municipalities, with 95 % of the population.

There are also nearly 100 affiliated members of the organisation such as consultants, producers, suppliers and institutions for

research and education. Norwegian Water serves both as a special interest organisation and a competence organisation for the members, within the vision of “clean water – our future”.

Norwegian Water Vangsvegen 143 – NO-2321 Hamar, Norway tel: +47 62 55 30 30 email: post@norskvann.no www.norskvann.no

idetrykk.no

Norwegian Water is a special interest organisation representing Norway’s water industry. The organisation is owned by the members, which are municipalities, companies owned by municipalities, municipal operational assistance organisations and some private water works.