Annual Report 2007

Eawag: Swiss Federal Institute of Aquatic Science and Technology Eawag, the Swiss Federal Institute of Aquatic Science and Technology, is part of the ETH Domain. This comprises the Swiss Federal Institutes of Technology in Zurich (ETHZ) and Lausanne (EPFL), Eawag and three other independent, ­application-oriented research institutes – the Paul Scherrer Institute (PSI), the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and the Materials Science and Technology Research Institution (Empa). Nationally rooted and internationally networked, Eawag is concerned with ­concepts and technologies for the sustainable management of water resour- ces and aquatic ecosystems. In cooperation with universities, other research ­centres, public authorities, the private sector and NGOs, Eawag strives to ­harmonize ecological, economic and social interests in water, providing a link between science and practical applications. About 400 staff are employed in ­research, teaching and consulting at the Dübendorf (Zurich) and Kastanien- baum (Lucerne) sites.

Cover photo Pilot plant for the ozonation of treated waste- water at the Regensdorf wastewater treat- ment plant near Zurich. Ozonation can reduce the remaining toxicity by 90 %. In the Micro- Poll project, initiated by the federal authorities, Eawag – in cooperation with various partners – is assessing whether an additional treatment step of this kind is worthwhile. Photo: Andri Bryner. Article: page 9. Content

2 Water research with high scientific and societal impact 4 Promoting partnership

6 Chemicals and their impacts 9 Closing gaps in wastewater treatment 13 Taking peak exposures into account 14 Where should hospital wastewater be treated? 15 Nitrosamines in water resources 16 Caffeine: a marker indicating the need for water protection 18 A plastic disc to replace a fish? 19 A climate record preserved in dripstone 20 Arsenic and uranium in Greek groundwater 21 The psychology of sand filter use

22 Aquatic ecosystems 25 Swiss-Chinese cooperation on the Yangtze 28 River ecology enhanced by experimental floods 29 The sound of rivers 30 How natural is the rehabilitated River Thur? 31 European rivers under pressure 32 Species boundaries set by the environment 33 Hard workers and cheaters in microecosystems 34 Wohlensee: lake flatulence and global warming 35 Lake Kivu: time bomb or energy resource?

36 Urban water management 39 Turning stakeholders into participants 42 Faecal sludge: health risk or natural resource? 43 Developing local expertise 44 Rapid detection of pathogens 45 Helping the helpers – a handbook for relief missions 46 Nutrient overload in the Tha Chin River 47 When tap water smells musty 48 Energy self-sufficiency for wastewater treatment plants? 49 Catching polluted road runoff in a filter bag 50 Forward-looking strategic planning for the sanitation sector

53 Eawag review of 2007 58 Books – and total immersion 58 An elegant sufficiency 59 A home from home 59 Green mobility 60 Organization 62 Finances 63 People 64 Activities 2 Letter from the director

Water research with high scientific and societal impact

In most industrialized countries, gross pollution, such as foaming rivers, is a thing of the past. However, newly-introduced or newly- detectable chemicals pose novel challenges for water researchers and the water management sector. Developing countries face more acute issues of safe water supply and sanitation. Eawag is support- ing the UN Millennium Development Goals through its research and its new partnership program. Janet Hering

Water is one of the prerequisites of life on our blue planet. Across the continuum from relatively unperturbed aquatic ecosystems to fully engineered wastewater treatment systems, water affects many areas of our lives – and lines for household-centred environmental sanitation are ­offers many fascinating topics for research. an important contribution to realizing the UN Millennium Development Goals (p. 39). Water quality issues in developed countries In recent years, research activities in developing and In developed countries, the acute water quality problems emerging countries have expanded beyond Sandec of the 20th century, such as eutrophication and uncon- to other Eawag departments. For example, Eawag re- trolled releases of industrial effluents, have been largely searchers have studied groundwater quality in South and solved. The increasingly widespread use of synthetic Southeast Asia, surface water quality in China, and the chemicals has, however, led to the ubiquitous occurrence opportunities and risks associated with energy generation in the aquatic environment of xenobiotic compounds, from naturally occurring methane in Lake Kivu in Africa many of which act as endocrine disruptors (e. g. damag- (pp. 25, 35). The Eawag Partnership Programme (EPP) ing reproductive organs or processes in fish). Eawag will facilitate and promote collaboration with students researchers have therefore been studying options for im- and researchers from developing and emerging countries proving the efficiency of micropollutant removal in munici- (p. 4). pal wastewater treatment plants (p. 9) and for implement- ing localized wastewater treatment at hospitals (p. 14). Engaging with stakeholders and the public Because water is such an integral part of our every­day Improving human welfare experience, Eawag’s activities must incorporate effective The UN-sponsored International Year of Sanitation in engagement and outreach to individuals. The cross-cut- 2008 highlights the critical importance of good sanitation ting Novaquatis project concluded with a well-attended to human health. Eawag has a long history of engagement and successful Information Day in March. In the same in improving sanitation, safe drinking water supply and month, the “Sound of Rivers” (p. 29) was part of a waste management in developing countries, particularly popular exhibit at the Muba Fair in Basel, and a beauti- through the activities of the Department of Water and fully illustrated book on the Vierwaldstättersee and its Sanitation in Developing Countries (Sandec). Our guide- surroundings was published with support from Eawag in October. The Forum Chriesbach building continues to be a source of great interest to the public and was visited by two members of the Federal Council in 2007. Emerging areas of activity Eawag researchers are constantly identifying new areas for research and new opportunities to address the prob- lems facing society. The questions of how climate change will affect water resources, water supply and aquatic ecosystems, and of how ecosystems and societies will adapt to these pressures, are emerging topics of research at Eawag. Another emerging topic is the fate and envi- ronmental effects of engineered nanomaterials. These research areas will be the subject of active investigation in the coming years. In 2008, Eawag will also initiate a new type of activity, with the opening of the Centre for Applied Ecotoxicology. This centre is designed to meet the critical needs of society, indus- The strength of try and regulators by providing practice- our research in oriented continuing education, contract research and ecotoxicological evaluation aquatic science and of chemicals. technology enables Eawag staff can be justifiably proud of us to address their many contributions to fundamental and applied research in aquatic science problems of broader and technology. Publications by Eawag societal impact. researchers appear in leading scientific and engineering journals and have a wide-ranging impact on the development of novel concepts and technologies. Eawag researchers are also leaders within the environ- mental science and engineering communities, where they are active as organizers of technical meetings and symposia, experts on advisory boards, invited speakers and reviewers, once again receiving many honours and awards in 2007. Although these activities may seem rather distant from the daily water-related concerns of individuals, the strength of fundamental and applied research in aquatic science and technology at Eawag also positions it to ad- dress problems of broader societal impact. The function of bridging between theory and practice is a key part of Eawag’s mission and mandate. Knowing that our work is put into practice to improve human well-being and environmental quality is a strong motivation for all of us at Eawag. i i i 4 Cooperation with developing countries

Promoting partnership

For many years, Eawag – through the Department of Water and Sanitation in Developing Countries (Sandec) – has been actively engaged in research in and for the benefit of countries where clean drinking water and safe disposal of wastewater and faecal matter cannot be taken for granted. Recently, other departments have also been increasingly concerned with water-related prob- lems in various regions of the developing world. To further strengthen this commitment, Eawag has launched a Partnership Programme for Developing Countries. Andri Bryner, Christoph Lüthi, Tom Gonser

For Eawag, research in developing countries is an impor- Institute for Water Education in Delft (the Netherlands), tant task. Water scarcity, environmental pollution, over- and a module providing support for curriculum develop- exploitation of resources and loss of biodiversity are just ment. some of the issues of growing concern in the develop- To ensure that exchanges are mutually beneficial, each ing world. Thanks to its multidisciplinary approach and its fellowship must be linked to a departmental project or a network of scientific partners and research centres in the senior scientist at Eawag. In addition, the research topic South and East, Eawag can increasingly provide practice- has to be of relevance within a development context, and oriented solutions. candidates are to be selected on the basis of the scien- tific quality of the proposed project. The EPP Selection Committee includes representatives of six Eawag depart- ments and Director Janet Hering. In March 2008, the first three fellowships were awarded to an MSc student from the Democratic Republic of the Congo and two PhD stu- dents from Ghana and China.

Visiting Scientist Programme The Visiting Scientist Programme will enable pre-eminent researchers and sector specialists from developing coun- tries to present their projects and discuss their findings with researchers at Eawag. This will also give Eawag staff

Fabrice Amisi is an MSc student from the Democratic Republic of the Congo. He is working in the Surface Waters Department on the quan- tification of external nutrient inputs to Lake Kivu. This requires the measurement of and collection of samples from tributaries, as shown in the photograph (see also page 35).

Fellowship Programme Existing research and training activities in this area are now being expanded with the launching of the Eawag Partnership Programme (EPP), which is mainly designed to build academic, professional and research capacity in Noah Adamtey is completing his doctoral thesis on “Enrichment of developing countries. A key element of the EPP activi- co-compost for periurban maize cultivation in Ghana” in the Depart- ties is the Fellowship Programme, which each year offers ment of Water and Sanitation in Developing Countries. In co-compost- six talented (preferably PhD) students from the develop- ing, organic wastes are composted together with faecal sludge. In this ing world, the opportunity to carry out research at Eawag process, pathogens are rendered harmless under controlled condi- tions, so that the compost can finally be safely used in agriculture. for 3–4 months. The other components of the EPP are a In cooperation with the local university and the municipal authorities Visiting Scientist Programme for experienced researchers Eawag has launched a co-composting plant in Kumasi (Ghana) as a and professionals, the partnership with the UNESCO-IHE ­pilot project (see also pages 42, 43). Cooperation with developing countries 5

Mingma Sherpa describes his experience My first contact with Eawag was in 2002, when the Sodis programme (solar water disinfection using PET bottles) was implemented in Nepal. I helped to test the effectiveness of Sodis at various altitudes in Nepal – from the slopes of the Himalayas down to the plains of the south. I worked initially as a researcher and later as a project coordinator for a Nepalese aid agency’s Sodis promotion programme. In 2003, I had the opportunity to take a Master’s degree in Environmental Science at the UNESCO-IHE Institute for Water Education in Delft (the Netherlands). For my Master’s thesis, I once again collaborated with Eawag, as the topic was faecal sludge management in Kathmandu Valley. I successfully com- pleted my MSc at the IHE thanks to expert supervision by Martin Strauss and Doulaye Kone at the Department of Water and Sanitation in Developing Countries, and with assistance from my advisor, Roshan Shrestha of the UN Human Settlements Programme (UN-Habitat) in Nepal. This cooperation between the IHE, Eawag and the UN offers many advantages: it meant that, although I was enrolled at an Institute in the Netherlands, I had the support Tao Zhang has previously carried out research at Nankai University in Tianjin (China). At Eawag’s Environmental Chemistry Department (in of the leading experts in the field of faecal sludge management. I was able to cooperation with Empa), he will continue with his thesis on perfluori- work on a topic which I find very interesting and which had previously been nated compounds (PFCs) in wastewater and in natural waters. PFCs scarcely studied in my home country. My work is now gradually bearing originate, for example, from stain-, grease- and waterproof coatings or fruit: for example, some of the results have been incorporated by UN-Habitat breathable fabrics. They have toxic effects, persist in the environment into a faecal sludge management strategy for the Bagmati region. In 2006, and are scarcely degraded by wastewater treatment. I started working for the same organization in Nepal again, as a wastewater and sanitation programme manager. I’m involved in the planning of a water supply system and an integrated programme to improve sanitation for a the opportunity to prepare new projects relevant to devel- community of 6000 people living near Kathmandu. Thanks to an intensive oping and transition countries, and to establish contacts campaign carried out in partnership with the community – involving more with potential research partners. than 100 composting toilets and other toilet facilities – we have reached the point where people no longer defecate in the open. We have also distributed Continuing the long-standing IHE partnership composting buckets to households, where they are consistently used. I Eawag’s partnership with the UNESCO-IHE Institute for am now also jointly responsible for coordinating other water and sanitation Water Education in Delft, which began 14 years ago, is programmes run by our organization and for the budget in this sector, and at now to be integrated into the EPP. Each year, three stu- the same time I’m trying to press on with my thesis at the Asian Institute of dents from developing countries taking an MSc at the IHE Technology in Bangkok. are to pursue their studies at Eawag. These exchanges will generally last half a year and also include fieldwork in the participant’s home country. Here, too, it is a re- quirement that the research topic should be of practical relevance to the student’s country of origin. A first-hand account of how this scheme can work is given by former MSc student Mingma Sherpa, who is now applying the knowledge he acquired through Eawag in his home coun- try Nepal (see Box).

Supporting education The fourth component of the EPP is support for the education of local specialists. For this purpose, the large number of Eawag scientists involved in teaching repre- sents a broad pool of expertise. Support may be provided in the development of training modules or the produc- tion of course material; equally, Eawag researchers may give a course or series of lectures themselves at a part- ner institution. Ultimately, this kind of capacity building should also promote research collaboration (see also Mingma Sherpa at a workshop on improving sanitation in Nepal. page 43). i i i Chemicals and their impacts

Some people are content when they see that something Substworks, but chemist Stephan Hug (50) is not one of ances them: he wants to know how it works. While this may be normal for a researcher, Hug is not satisfied either with theories developed under sterile laboratory conditions, as commonly found in academic research. Hug is con- Herbicides, fungicides, algicides, disinfectants, vinced that “The key to understanding lies in studying cleaning agents, pharmaceuticals and nano­ the actual environment,” and this he considers to be one particles – the list of substances detected in of Eawag’s great strengths. Often, as Hug points out, the surface waters is growing longer and longer. crucial processes occur at interfaces – for example, on But very often it is unclear where exactly the u­ltrafine particles suspended in water: “If you only work substances come from and what effects they with pure substances, you’ll never really understand have in the environment. Aquatic research at what’s going on.” Hug originally trained as a chemical Eawag explores these questions, but even laboratory technician, before studying at a university of when answers have been found, the problems applied science and at Bern University. Having obtained are not necessarilyin solved. For example, is it Wahis doctorate at the ter worthwhile upgrading wastewater treatment University of Califor- plants with additional technologies? Or could nia, he was a post- other measures be more effective for avoiding doctoral fellow at releases of problematic substances? Here, there Stanford University. is a need to consider economic, social and Throughout his ca- frequently also political aspects – in the light reer, while specializ- of our scientific findings. ing in photochemical and surface chemi- cal processes, he has never lost sight of his goal: scientific understanding must ultimately lead to practical applications. As well as lead- ing to the release of problematic substances, photo- chemical and surface reactions may eliminate the toxicity of chemicals. Accordingly, Hug’s research at Eawag has focused not only on how UV light kills microorganisms (as in the Sodis method of solar water disinfection), but also on how it can render contaminants such as arsenic or hexavalent chromium harmless. While photochemical water treatment still requires further development, other processes investigated by Hug’s group are being applied in practice – for example, the use of sand filters to re- move arsenic from drinking water in Bangladesh, Viet- nam and Greece (pages 19, 20). Environmental engineer Nathalie Vallotton (30) hails from Lausanne and (as she is frequently asked) is related to the painter Félix Vallotton. She specializes in risk ­assessments – a topic she had already chosen for her disser­tation at the Federal Institute of Technology (EPFL), which was concerned with leachate from a land- fill in Ho Chi Minh City (Vietnam). In the Environmental Toxicology Depart- ment at Eawag, Val- Agricultural engineer Christoph Ort (33) was repeatedly lotton subsequently told that it was barely possible to predict when, and in wrote her doctoral what concentrations, pollutants flow through sewers. thesis on the effects “Not even daily loads were considered to be predicta- of peak exposures of ble,” he says. However, by skilfully combining analytical herbicides on algae chemistry with a stochastic model, Ort managed to rem- Subst ances(page 13). Although edy this deficiency in his dissertation. In doing so, he she had not been sought support from various departments at Eawag: ­intent on obtaining a “The open doors were extremely helpful.” His predic- doctorate from the tions agree closely with the results of costly individual start, she says, she measurements and realized that a disser- can even reveal tation was the best way of learning more about environ- peaks at a temporal mental toxicology. She is now an expert in this field and, resolution in the as she puts it, “a bit closer to being able to assess these minute range. In the effects, with a view to understanding the effects ob- MicroPoll project served and the quality of waterbodies”. As it is difficult sponsored by the even to detect peak exposures by means of sampling, Federal Office for scant reliable data have been available so far on the the Environment ­effects of such pulses, which may derive, incidentally, (FOEN), Ort now in Wa ternot only from agriculture but also from traffic or urban has the opportunity, sources. For Vallotton, scientific insights are not enough: as an Eawag post- thanks to Eawag’s cooperation with authorities and agri- doc, to apply his cultural research institutes, measures designed to reduce interdisciplinary approach on a large scale: using a agrochemical pollution of surface waters have already ­national material flow model (page 9), he has predicted been taken – including increased training for farmers on what micropollutant loads are to be expected for all the management of these substances. Finally, Vallotton wastewater treatment plants, and where critical inputs of mentions another practical concern: “People should effluent into streams could occur under dry weather con- speak more French at Eawag.” ditions – with more than a hundred plants affected. Do all of these plants now need to be upgraded with additional technology? Ort cites the principle “As simple as possi- ble, as complex as necessary.” He adds that, alongside technical measures, efforts are needed to promote more careful management of substances potentially hazardous to the environment. Ort is already involved in the FOEN pilot study at the Regensdorf wastewater treatment plant. Here, treated wastewater undergoes ozonation ­before being discharged into a small stream. With the scientist’s curiosity, he admits: “It’s fascinating to be among the first to be able to try out this process at full scale – whether or not it will later become common ­practice.”

Chemicals and their impacts 9 in waste-Closing gaps watertreatment

Organic micropollutants, such as ingredients of cleaning agents or active substances of medicines, are not completely eliminated at wastewater treatment plants (WWTPs). This means that they are dis- charged into creeks, rivers and lakes, where they may have adverse effects on the ecosystem. In the MicroPoll project, researchers are assessing possible countermeasures – including an additional treat- ment step at WWTPs, which has already produced encouraging initial results. Christoph Ort, Hansruedi Siegrist, Juliane Hollender und Beate Escher

Representative sampling and quantification of a wide variety of organic micropollutants is extremely costly. If efforts are restricted to a reasonable and financially acceptable level, it is only possible to obtain a “snapshot”, the substance concerned. We also take into account infor- limited in space and time. Online analytical instruments mation on the use and fate of substances, e. g. prescribed capable of measuring these substances directly and con- doses and known rates of excretion. tinuously in surface waters do not (yet) exist – and even if they were available, they could be used only to record Case of carbamazepine existing conditions, and not to make predictions. A number of studies, including our own, have shown that We therefore developed a national material flow model elimination of the antiepileptic agent carbamazepine at [1], which describes current loads of selected micropol- WWTPs is currently minimal. Under the assumption that lutants in surface waters downstream of the 742 WWTPs on average almost 10 % of the carbamazepine ingested serving more than 500 population equivalents. In addition, is excreted from the human body in unchanged form, the model can be used to calculate future scenarios and and that the substance is not degraded in natural surface carry out cost/benefit analyses. The key input variables waters, the model calculates the average annual mass for our model are the quantities of a given substance con- flows to be expected. In Fig. 1, the values predicted by sumed and data on the WWTPs, including the number of the model for 26 catchments of different sizes are plotted inhabitants served, the sites where effluent is discharged against the loads measured. With only a few exceptions, to receiving waters and the elimination performance for the results generated by the model are in close agree- ment with reality. For household chemicals and medi- cines, deviation by a factor of 2 is not unusual and reflects the variability over time that is to be expected at a given site [3].

Micropollutants may accumulate in fish tissue or – in the case of endocrine disruptors – produce abnormalities in the reproductive organs (Foto: Bavarian Environment Agency). Top: Removal of fish from the Furtbach stream above the point where effluent is dis- charged from the WWTP in Regensdorf. Bottom: European chub. 10 Chemicals and their impacts

200 1000 000 100 500 000 50 200 000 20 100 000 10 50 000 5 20 000 2 10 000 1 Catchment size [inhabitants] 1 2 5 10 20 50 100 200 Measured carbamazepine load [g/day] Predicted carbamazepine load [g/day]

Canton Zurich (grab samples) Canton St Gallen (composite samples) Furtbach R’dorf (composite sample) National campaign (grab samples)

Fig. 1: Daily loads of carbamazepine in 26 river sections, by catchment size. The dotted lines indicate a deviation by a factor of 2 from the ­values predicted by the model. Ozonation of previously treated wastewater can reduce the remaining toxicity by 90 %.

Figure 2 provides an overview of the total hazard potential

predicted for carbamazepine in rivers at base flow Q347 course. The material flow model was tested in a measure- (i. e. the flow rate attained or exceeded 95 % of the ment programme involving the collection of samples from time). If no measurements of flow rates below a WWTP 10 rivers and 15 WWTPs. The results obtained for three of were available, values were interpolated. The results these rivers (Töss, Ergolz and Seyon) are shown in Fig. 3. show that the quality standard of 0.5 µg/l proposed for Here, the carbamazepine loads expected on average lead carbamazepine by the German Working Group of the to exceedance of the quality standard for periods ranging Federal States on water issues (LAWA) is exceeded in riv- from no or only a few days to several months per year. ers and streams below almost 100 of the 742 major Swiss The duration of exceedance varies widely from year to

WWTPs. The base flow Q347 represents a “worst case” year. Peaks occur in years with prolonged dry periods, since dilution of the effluent in receiving waters is low un- such as the summer heat wave of 2003. der such conditions. The period during which the quality standard is actually exceeded in specific cases depends Extension strategies largely on the annual flow regime in the individual water- If the periods during which excessive loads are expected to occur in surface waters are to be reduced, an additional treatment step would need to be implemented at the WWTPs concerned. Pilot studies on a small scale have Carbamazepine + metabolites at base flow Q 347 shown that, for many micropollutants, elimination rates # < 0.01 µg/l # Dischrge to lake # 0.01–0.1 µg/l > Extension strategy “Effect” # 0.1–0.5 µg/l 10 # 0.5–1.0 µg/l L max # > 1.0 µg/l 8 > no Q347

L mean 6 [months] L 4 min

carbamazepine 2

of QS 0 2003 2004 2005 2006 2007

Theoretical duration of exceedance Töss Ergolz Seyon (above Rhine) (above Rhine) (Lake Neuchâtel)

Fig. 3 Periods during which carbamazepine concentrations theoreti- cally exceeded the quality standard (QS – suggested by the LAWA) of 0.5 µg/l. The duration of exceedance is also shown for carbamazepine

Data: Eawag/FOEN 2006/07 loads of twice (Lmax) and half (Lmin) the expected value (Lmean). Map reproduced by permission of swisstopo (BA081043).

Fig. 2 Modelled carbamazepine hazard potential in rivers at base flow Q347. Black rings indicate wastewater treatment plants that would need to be upgraded to ensure that concentrations of carbamazepine (including metabolites) do not exceed 0.5 µg/l in any surface waters. Chemicals and their impacts 11

of 95 % or more could be achieved through the use of activated carbon filtration or advanced oxidation of treated wastewater. Assuming that inputs of substances to wastewater cannot be prevented by means of prohibi- tions or other at-source measures, the following strate- MicroPoll gies are conceivable: Aquatic micropollutants currently feature prominently in discussions of surface water assessment, drinking water processing and wastewater treatment. But do organic micro­ E “Effect” strategy: pollutants really pose a problem at concentrations ranging from millionths to billionths of Additional treatment processes would be implemented at a gram per litre (e. g. compounds found in detergents and cosmetics, or active ingredients the minimum number of WWTPs required to ensure that of pharmaceuticals)? As part of the “MicroPoll strategy” – an interdisciplinary project the desired quality standard at base flow is no longer ex- launched by the Federal Office for the Environment (FOEN) – research is focusing on the ceeded in downstream river sections. This would involve question of micropollutants from urban drainage. Ecotoxicologists are seeking ways to identify problematic substances and to determine the concentrations at which these pollut- at least 80 plants, serving around 10 % of the population ants have (adverse) effects on organisms. Chemists are developing methods to allow water (see Fig. 2). samples to be screened as accurately as possible for such compounds. Efforts in both of E “Load” strategy: these areas are providing valuable information on the current state of our surface waters. In line with the precautionary principle, the aim would be The overall aim is to formulate a national strategy for reducing inputs of micropollutants to to achieve the greatest possible load reduction nation- receiving waters. Also participating in the MicroPoll project, alongside the FOEN and Eawag, are the Federal Institute of Technology Lausanne (EPFL), cantonal environmental protection wide, with measures only being considered for WWTPs agencies and the Swiss Water Pollution Control Association (VSA). Further details are avail- serving at least 10,000 population equivalents. In this able at www.umwelt-schweiz.ch/micropoll [2]. case, more than 250 plants would be involved (serving around 90 % of the population). However, the quality standard for carbamazepine would still be exceeded at a 24-hour period, the average proportion of wastewater in about 40 smaller WWTPs. the stream just below the plant is 60 %; in other words, What we have shown in the case of carbamazepine is also the effluent discharged by the WTTP is only diluted by applicable for other micropollutants: in the case of the a factor of 1.7. Taking the examples of carbamazepine anti-inflammatory agent diclofenac (average consump- and diazinon, Fig. 4 shows the correspondingly sharp tion approx. 4000 kg per year in Switzerland, according increase in concentrations of micropollutants in the Furt- to IMS Health GmbH), we calculated that concentrations bach stream after the release of treated wastewater. At in receiving waters at base flow would exceed the quality the WWTP, carbamazepine is scarcely eliminated at all, standard of 0.1 µg/l at more than 170 WWTPs. while the insecticide diazinon is only partly eliminated.

Full-scale trial in Regensdorf To determine whether the results achieved in pilot studies can be reproduced with a full-scale system, an ozonation process is currently being tested at the Wüeri WTTP in Regensdorf (Canton Zurich). The trial is also designed to determine how much energy is required for full-scale operation of an additional treatment step and what de- mands it places on staff at a municipal WWTP. The Wüeri WTTP was chosen as the test site because the plant is technologically advanced and is situated on the small Furtbach stream. With substantial fluctuations over

10 000 ARA Diazinon Furtbach Carbamazepine 1000 * below limit of detection

100

10 Concentration [ng/l] 1 * VK NK SF FO FU The treated wastewater discharged into the Furtbach stream is only weakly diluted, particularly during low-flow conditions. Fig. 4: Concentrations of diazinon and carbamazepine measured over a 1-week period at the Wüeri WWTP in Regensdorf. VK = primary cla- rifier, NK = secondary clarifier, SF = sand filter effluent, FO = Furtbach above WWTP, FU = Furtbach below WWTP. Modified from [5]. 12 Chemicals and their impacts

Hazard potential In order to draw conclusions about the risk posed to surface ­waters by measured or predicted concentrations, it is necessary to know the hazard potential of the substance under investiga- tion. This value is determined experimentally in the laboratory with the aid of elaborate ecotoxicity tests involving, for example, ­algae, daphnia (water fleas) or fish. The results of these studies are used to derive a concentration below which no adverse effects are ­expected to occur in the ecosystem concerned – the PNEC (pre- dicted no effect concentration). It is important that biotransforma- tion products (metabolites) should be taken into account as well as the parent compound. In the case of carbamazepine, about 40 % of the active substance is excreted as metabolites formed in the body. These compounds increase the hazard potential by around 25 % [4]. Clarifier at the WWTP Regensdorf. The tank containing liquid oxygen for ozone production can In addition, it is necessary to distinguish between the baseline be seen in the background. ­toxicity of a compound or group of compounds and specific modes of toxic action – e. g. endocrine disruption or insecticidal effects (see Fig. 5). In general, given the high costs involved, samples can only be analysed for a limited number of micropollutants, and the effects of mixtures are largely unknown. However, ecotoxicity tests covering various modes of toxic action not reveal any increases in toxicity, which suggests that make it possible to obtain a more comprehensive assess- the process does not give rise to any toxic by-products. ment of the treatment performance of WWTPs (see also These findings, which were confirmed by chemical analy- the “Hazard potential” Box). At the plant in Regensdorf, sis for individual substances, are highly encouraging. The Eawag applied an ecotoxicological test battery [6]. trial in Regensdorf is to run until the end of 2008. During Figure 5 shows how the toxicity of micropollutants in this period, different modes of operation are to be tested wastewater was reduced as a result of the treatment and, in particular, control systems are to be further opti- processes – by more than 90 % overall, although major mized. The combined efforts of water pollution control differences were seen, depending on the substance and authorities, ecotoxicologists, environmental chemists, re- mode of action. The first measurements performed after search engineers and practitioners, and WWTP staff will the implementation of ozonation demonstrate that this ad- allow valuable experience to be accumulated, facilitating ditional treatment can reduce the remaining toxicity by a future decisions in the area of centralized wastewater further 90 %. Just as importantly, the ecotoxicity tests did treatment. i i i

6 [1] Ort C., Siegrist H., Hosbach H., Studer C., Morf L. und ARA Furtbach 91 ARA Furtbach 5 ­Scheringer M. (2007): Mikroverunreinigungen – Erarbeitung Bioluminescence test 6 Herbicides: einer Strategie. Gas Wasser Abwasser 11, 853–859. 4 Algal growth test Diuron equivalents [µg/l] [2] Schärer M., Müller S. und Sieber U. (2007): Mikroverunreini- Insecticides: 3 4 gungen – Erarbeitung einer Strategie. Gas Wasser Abwasser Parathion equivalents [µg/l] [mg/l] 11, 835–841. 2 Estrogens:

Baseline TEQ [3] Giger W., Schaffner C. and Kohler H.P.E. (2006): Benzotri- 2 Estradiol equivalent [ng/l] 1 azole and tolyltriazole as aquatic contaminants. 1. Input and TEQ from bioassays for 0 specific modes of action 0 ­occurrence in rivers and lakes. Environ. Sci. Technol. 40 (23), VK NK SF FO FU VK NK SF FO FU 7186–7192. [4] Lienert J., Gudel K. and Escher B.I. (2007): Screening method Fig. 5: Average toxicity values (toxic equivalents/TEQ) determined at the Wüeri WWTP in for ecotoxicological hazard assessment of 42 pharmaceuticals ­Regensdorf using an ecotoxicological test battery over a 1-week sampling period [6]. Left: considering human metabolism and excretory routes. Environ. Baseline TEQ for a large group of compounds (including carbamazepine). Right: TEQ from Sci. Technol. 41 (12), 4471–4478. ­bioassays for specific modes of action, e. g. parathion equivalent concentrations (including [5] Hollender J., McArdell C.S. und Escher B.I. (2007): Mikro­ the contribution of diazinon). VK = primary clarifier, NK = secondary clarifier, SF = sand filter verunreinigungen: Vorkommen in Gewässern der Schweiz und ­effluent, FO = Furtbach above WWTP, FU = Furtbach below WWTP. Bewertung. Gas Wasser Abwasser 11, 843–851. [6] Escher B.I., Bramaz N., Quayle P., Rutishauser S. (2008): ­Monitoring of the ecotoxicological hazard potential by polar ­organic micropollutants in sewage treatment plants and surface waters using a mode-of-action based test battery. J. Env. Monitor. 10, 622–63. Chemicals and their impacts 13

Taking peak exposures into account

Herbicides used in crop production may enter aquatic ecosystems via surface runoff, especially after heavy rainfall. Wide variations in concentrations are generally not detected by routine measure- ments. However, peak exposures have toxic effects, for example on algae. The existing non-specific quality criteria need to be amended. Nathalie Vallotton, Rik I.L. Eggen, Nathalie Chèvre1

Under the Swiss Water Protection the chloroacetanilide S‑metolachlor, Ordinance, concentrations of organic which inhibits fatty acid biosynthe- pesticides in surface waters are sis. All three products are widely required not to exceed 0.1 µg/l per applied in agriculture on cereals and individual substance. From an eco- corn crops and are commonly de- toxicological viewpoint, this limit is tected in surface waters. unsatisfactory since substances with quite different modes of action are all Varying effects assessed by the same standard, and For all the herbicides studied, toxic the effects of mixtures of pesticides effects on growth increased with are not taken into consideration. increasing exposure duration and In addition, peak concentrations in concentrations. However, the rise in streams frequently – albeit tempo- toxicity varied widely, depending on rarily – exceed not only the chronic the type of herbicide. Considerable The ecotoxicological effects of herbicides depend on a variety of ­factors. water quality criteria (CQC) appli- differences were also observed in cable to all pesticides, but also the the time to onset of toxic effects limits recently proposed for specific and in the recovery of algae follow- substances. ing pulse exposure: with the PSII effects on growth and photosynthe- inhibitors, algal growth inhibition sis were reversible after each ex- Widely used products occurred within only a few hours, posure, the cumulative decrease in Conventional laboratory tests usu- but algae recovered again almost as biomass production may affect the ally assess toxic effects in algae or rapidly in clean water. In the case of composition of algal communities in aquatic plants exposed to constant S-metolachlor, on the other hand, the environment. concentrations for several days. effects on algal division were only As peak herbicidal exposures have ­Effects caused by single or multiple observed if exposure coincided with been shown to induce toxic effects peak exposures are not evaluated. a specific development stage, while in algae, the level and the number We therefore investigated how the recovery was seen after a delay of of exceedances of the CQC should green alga Scenedesmus vacuola­ 29 hours. These differences may be be limited. In addition, more strin- tus reacts to various exposure sce- attributable to the mode of action of gent requirements should be speci- narios and how well it recovers after the herbicide and the type of binding fied for herbicides with delayed each exposure. We selected three at the target site. e­ffects. i i i herbicides with different modes of The effects of repeated exposure action – the photosystem II (PSII) in- to the PSII inhibitor isoproturon hibitors atrazine and isoproturon, and are shown in the Figure. While the 1 University of Lausanne.

0 100

80 –1 60 This study was funded by the Velux Foundation and the Swiss ­National Science Foundation. 40 –2 Vallotton N. (2007): Effect assessment of fluctuating exposure

Inhibition[%] Vallotton N. (2007): Effect assessment of fluctuating exposure 20 of herbicides with different modes of action on algae.­ PhD

Optical cell density [log] – 3 0 ­thesis, ETHZ. 0 20 40 60 80 100 120 140 160 Vallotton N., Eggen R.I.L., Escher B.I., Krayenbühl J., Chèvre N. Time[h] (2008): Effect­ of pulse herbicidal exposure on Scenedesmus Exposure Inhibition of photosynthesis [%] Algal growth vacuolatus: a comparison of two photosystem II inhibitors. ­Environmental toxicology and chemistry, accepted. The growth and photosynthetic yield of algae are strongly inhibited during each exposure ­Environmental toxicology and chemistry, accepted. Chèvre N. (2006): Pestizide in Schweizer Oberflächengewässern: (5 hours/day) to the herbicide isoproturon; however, they recover between exposures. The Chèvre N. (2006): Pestizide in Schweizer Oberflächengewässern: Wirkungsbasierte Qualitätskriterien; Gas Wasser Abwasser 4, ­decrease in cell density after each exposure is due to the experimental procedure – the algal Wirkungsbasierte Qualitätskriterien; Gas Wasser Abwasser 4, 297–307. cultures have to be diluted to permit renewed growth. 297–307. 14 Chemicals and their impacts

Where should hospital wastewater be treated? Hospitals are generally regarded as point sources for pharmaceuticals. A study ­performed at Winterthur Cantonal Hospital showed that concentrations in waste­ water vary widely, and that by no means all the substances dispensed are also excreted at the hospital. In view of these findings, the question whether separate treatment of hospital wastewater is worthwhile requires further investigation. Christa S. McArdell, David Weissbrodt, Lubomira Kovalova, Juliane Hollender, Hansruedi Siegrist

According to estimates of the con- In addition, we analysed samples for 5-fluorouracil and gemcitabine in sumption of pharmaceuticals drawn selected agents and quantified the the wastewater. This can be partly up as part of the MicroPoll project corresponding mass fluxes in hospi- explained by the high proportion of (see page 9), about tal wastewater. these agents (70 %) dispensed to It cannot yet be 18 % of all medicines Initial analyses were carried out at outpatients. said whether sold in Switzerland are Winterthur Cantonal Hospital in May separate treatment dispensed in hospitals. 2007. Over a 1‑week period, samples No “best available However, the percent- were collected from the sewer in technology” of hospital age for hospital use proportion to the volume of efflu- Various strategies are conceivable wastewater is is much higher in the ent. The agents studied were repre- for preventing pharmaceuticals in worthwhile. case of certain types of sentatives of the class of cytostatics, hospital wastewater from entering substance, e. g. X-ray which are undesirable in the environ- the ­environment. Under the leader- contrast media or cancer drugs (cy- ment on account of their frequently ship of Eawag, a working group on tostatics). carcinogenic effects, and contrast “Hospital wastewater” has therefore media. Although the latter are of less been established, comprised of ex- Dispensing ≠ excretion toxicological concern, they are envi- perts from the Federal Office for the The quantities of medicines dis- ronmentally persistent. Environment, cantonal authorities pensed cannot simply be equated and engineering consultancies. One with those subsequently found in Numerous outpatients of the main goals is to reach scientifi- hospital wastewater. The propor- The results show that the loads vary cally based conclusions as to wheth- tion excreted varies widely from one widely both in the course of the day er hospital wastewater requires sep- substance to another and, moreover, and from one day to another, depend- arate treatment, and if so, whether medicines are also dispensed to hos- ing on the quantities consumed at this would be best carried out on pital outpatients. To determine the the hospital. The highest concentra- site or in additional treatment steps actual proportion of pharmaceuticals tions – up to 1700 µg/l – were found at wastewater treatment plants. A in hospital wastewater, we therefore in the case of the contrast medium pilot plant combining a membrane collated statistics on consumption iomeprol, while the maximum con- bioreactor with advanced oxidation and known data on rates of excretion. centrations detected for the cancer is currently being installed at Baden drug 5-fluorouracil were only 30 ng/l. Cantonal Hospital in order to accu- The concentration profile for the mulate further experience, since no Weekend 600 30 3-hour composite samples reflects “best available technology” exists the predicted excretion rates. The as yet for hospital wastewater treat- 500 25 fraction of contrast media excreted ment.

/hour) i i i 3 400 20 within 2 hours is 50 %; accordingly, after administration in the morning, 300 15 This project is supported by the State a peak concentration is found around Secretariat for Education and Research,

Load (g/day) 200 10 midday. the EU project Neptune, the Federal Comparison with the 2006 consump- Office for the Environment, Cantons 100 5 Bern, Basel District, Geneva, St. Gallen, Mean water flow (m tion statistics for contrast media Schaffhausen, Solothurn, Schwyz, Thur- 0 0 shows that the loads measured Mo Di Mi Do Fr Sa So Mo gau, Vaud and Zurich, and the Holinger correspond to 25–50 % of average (Liestal) and Hunziker (Winterthur) engi- Iopromide Ioxitalamic acid consumption. In the case of cyto- neering consultancies. Iopamidol Diatrizoate Iomeprol Mean water flow statics, precise consumption figures Moser R., McArdell C.S., Weissbrodt D. Iohexol are available for the measurement (2007): Mikroverunreinigungen: Vorbehandlung von Spitalabwasser. Mass fluxes of X-ray contrast media in wastewater from Winterthur period. However, we found only GWA 11, 869– 875. Cantonal Hospital over a 1-week period. 1– 4 % of the expected amounts of Chemicals and their impacts 15

Nitrosamines in water resources

Carcinogenic nitrosamines can enter surface waters – and possibly also groundwater – via wastewater. Eawag has developed an analytical method capable of detecting these unwanted compounds in wastewater samples and measuring concentrations in the nanogram range. The results obtained at Swiss wastewater treatment plants are reassuring. Martin Krauss, Philipp Longrée, Juliane Hollender

The discovery of carcinogenic nitro- larly in wastewater samples, reliable 100 samines, especially N-nitrosodimeth- measurement is hampered by the Primary effluent Secondary effluent ylamine (NDMA), in wastewater and presence of a large number of in- 80 drinking water has raised concerns, terfering matrix compounds, so that 60 initially in North America and more not only high sensitivity but also high recently also in Europe. In North selectivity is necessary to ensure un- 40 NDMA [ng/l] America, nitrosamines mainly arise equivocal quantification. Our method 20 as a by-product of chlorine or chlor­ allows nitrosamines to be measured 0 ** * amine disinfection of wastewater in concentrations as low as 1 ng/l. 1 2 3 4 5 6 7 8 9 10 11 12 13 and drinking water. However, as It involves preconcentration of the Wastewater treatment plant these unwanted substances also water sample by a factor of 500 by Concentrations of NDMA in primary and secondary effluent at derive from industrial and household solid-phase extraction, followed by 13 Swiss wastewater treatment plants. * = below the detection limit sources, they may likewise occur in separation using liquid chromatogra- of 1 ng/l. countries such as Switzerland that phy and measurement of nine nitro- rely primarily on other methods samines by high-resolution tandem of water disinfection. At Eawag, a mass spectrometry (LTQ Orbitrap contamination of treated wastewater sophisticated analytical method has system). with nitrosamines in Switzerland can been developed for the determina- be classified as low-level. tion of nitrosamines. Measurements at As part of the EU RECLAIM WATER Swiss WWTPs project, we are currently monitoring Analytical challenges To gain an overview of nitrosamine the occurrence and elimination of The detection of NDMA and other concentrations in wastewater in nitrosamines in wastewater streams nitrosamines in the low nanogram Switzerland, we analysed 24-hour used for artificial groundwater re- per litre range is a highly demand- composite samples from 13 more or charge at facilities in Israel, Italy, Bel- ing analytical task. Enrichment of the less technologically advanced waste gium and Spain. The results indicate small, uncharged and highly soluble water treatment plants. In the prima- that nitrosamines are largely elimi- compounds from water requires the ry effluent, concentrations of NDMA nated in the course of wastewater use of specific adsorbents. Particu- approaching 100 ng/l were found treatment and aquifer passage. When in some cases. At all the WWTPs, groundwater was recovered, only high levels of NDMA were markedly NDMA was found in some cases at reduced by biological wastewater concentrations below 10 ng/l. i i i treatment, and in all cases concentra- tions were below 20 ng/l before the secondary effluent was discharged to receiving waters. Among the other nitrosamines meas- ured, N-nitrosomorpholine was found at all WWTPs in concentrations of up to 30 ng/l. For N-nitrosodiethylamine, N‑nitrosopiperidine and N-nitroso- di-n-butylamine, individual samples showed concentrations of up to 20 ng/l. These four compounds were Krauss M., Hollender J. (2008): Analysis also largely eliminated by biological of nitrosamines in wastewater: Ex- wastewater treatment, so that the ploring the trace level quantification concentrations in the secondary efflu- capabilities of a hybrid linear ion ent were generally below 5 ng/l. On trap/Orbitrap mass spectrometer. Martin Krauss working at the high-resolution ­Analytical Chemistry 80, 834–842. tandem mass spectrometer (LTQ Orbitrap the basis of these findings, compared www.reclaim-water.org system). with the situation in North America, 16 Chemicals and their impacts

Caffeine: a marker indicating the need for water protection Should concentrations of pharmaceuticals, biocides or caffeine be measured even when they are so low that there is no immediate threat to river ecosystems or individ- ual species? Yes, they should, since these measurements provide valuable pointers to where water protection measures would be most effective – long before pollution starts killing fish. Alfredo C. Alder, Zaharie Moldovan

In recent years, numerous studies the medicines carbamazepine, ibu- In contrast to carbamazepine, caf- have been carried out in Europe and profen, diazepam and pentoxifylline, feine is efficiently eliminated at North America on the occurrence and the musk fragrances tonalide WWTPs (> 99 %). Concentrations of of pharmaceuticals and fragrances and galaxolide. In addition, samples caffeine in the river can therefore in effluents and surface waters. were analysed for caffeine and for serve as a chemical indicator of However, scant data are available the biocide triclosan, which is used untreated municipal wastewater. from Eastern Europe and develop- as an antimicrobial or preservative. Caffeine concentrations in the efflu- ing countries. This lack is worrisome The Little Somes (Romanian: Some­ ent of most WWTPs varied between for two reasons: firstly, it is scarcely sul Mic) rises to the south of Cluj- 24,000 and 42,000 ng/l. These very possible to assess the local situation Napoca and merges with the Great high levels suggest that the facilities using data obtained elsewhere, since Somes (Somesul Mare) at Dej. The are not operating effectively or are consumption levels vary widely from Somes then flows westward for completely overloaded. One excep- country to country. Secondly, it is not 370 km to join the Tisza (a tributary tion is the efficient plant at Cluj-Na- possible to conclude where untreated of the Danube) in Hungary. Along poca, where caffeine concentrations or poorly treated wastewater is being the 250-km Romanian stretch of the of only 30 ng/l were measured in the discharged into surface waters. river, we collected grab samples sev- treated wastewater. Caffeine levels eral kilometres upstream and down- in poorly treated or raw wastewater Medicines and caffeine stream of wastewater treatment are thus around three orders of As part of the Swiss-Romanian re- plants (WWTPs) and analysed these magnitude greater than in the WWTP search collaboration sponsored by using directly coupled gas chroma- effluent at Cluj-Napoca. the Swiss National Science Founda- tography-mass spectrometry. Caffeine concentrations in the tion (see Box), we determined the Somes, varying between 110 and concentrations and loads of specific Concentrations lower than 330 ng/l, were comparable to those pharmaceuticals and fragrances in in Switzerland measured in Swiss rivers. Caffeine the Somes watershed in Transylva- The anticonvulsant carbamazepine loads rose from less than 600 g/day nia. The substances studied were is scarcely eliminated at WWTPs in the Little Somes to 2400 g/day and is therefore a useful indicator of ­after the confluence with the Great the level of discharges of municipal Somes. Theiss Theiss UKRAINE wastewater into a river. The concen- trations measured in the effluents Wastewater inflows from of Romanian WWTPs ranged from Great Somes

Baia Mare 210 to 770 ng/l. In the river, concen- At Dej, loads of the poorly biodegrad- Satu Mare trations were relatively constant at able substance carbamazepine in- 20–60 ng/l. They are thus an order of creased by a factor of 2– 3 as a result

HUNGARY Lapus Nasaud magnitude lower in the Somes than of wastewater discharges into the Somes Bistrita in the rivers of Switzerland or other river. The disproportionate increase Jibou Rus Beclean Dej Western European rivers. This may in caffeine loads by a factor of 4

Gherla be due to two factors: either car- below Cluj-Napoca indicates inputs ROMANIA bamazepine is less widely used in of untreated wastewater. As the rise Oradea Cluj- Romania, or the proportion of efflu- is most marked at Dej, it must be due National borders Napoca Tirgumures ent in the river is lower (i. e. waste- to inflows of untreated wastewater Tisza watershed water is highly diluted). from the Great Somes – originating Somes watershed 50 km The daily loads varied between from the cities of Bistrita, Nasaud 78 g/day below Cluj-Napoca and and Beclean (combined population The population of the Somes watershed is 1.8 million. The main 210–230 g/day after the conflu- of approx. 115,000). Downstream of wastewater treatment plants are at Cluj-Napoca (350,000 inhabitants), Gherla (30,000), Dej (75,000), Baia Mare (200,000) and Satu Mare ence of the Little and Great Somes Dej, despite inputs from further cities (150,000). (Fig. 2). such as Jibou, Baia Mare and Satu Chemicals and their impacts 17

ESTROM – Swiss contribution to water research in Romania The ESTROM (Environmental Science and Technology in Romania) research programme was jointly funded by the Swiss National ­Science Foundation, the Swiss Agency for Development and Co- operation, and the Romanian Ministry for Education and Research. The aim of the programme was to study the extent and impacts of water pollution at selected sites in Romania and to provide a ­basis for decisions on measures to protect ecosystems and human health. With a budget of CHF 1.5 million, nine projects were ­supported. Five Eawag researchers were involved as Swiss part- ners, and Professor Walter Giger (also of Eawag) chaired the ESTROM Steering Committee. The results of this research are to be presented to water protection professionals and officials at an inter­national conference in Bucharest (3–5 September 2008). Further information is available at: www.estrom.ch and www.cnmp.ro/estrom.php

findings indicate that other substanc- es and mixtures may also be entering the Somes with inputs of untreated wastewater. To improve water qual- ity, therefore, the WWTPs along the Great Somes, in particular, need to be upgraded. The rapid rise in caf- feine concentrations downstream of Baia Mare also suggests that the performance of the WWTP there is inadequate. i i i

Top: River scene in Romania. Bottom: Sampling at a barely functional wastewater treatment plant in the Somes watershed.

Mare, the loads remained relatively Toxicologically, the concentrations constant since caffeine is partly de- of the substances measured do not graded in the river. give cause for concern. However, our

300 3000

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50 Caffeine [g/day] 500 Carbamazepine [g/day] 0 0 Dej Dej Moldovan Z., Schmutzer G., Tusa F., Rus Rus Jibou Jibou Gherla Gherla Calin R., Alder AC. (2007): A first overview of pharmaceuticals and Baia-Mare Baia-Mare Satu-Mare Satu-Mare Cluj-Napoca Cluj-Napoca personal care products contamina- tion along of the river Somes water- Mass fluxes of carbamazepine and caffeine in the Somes. The water samples were collected shed, Romania. J. Environ. Monit. 9, upstream (orange) and downstream (brown) of where tributaries or WWTP effluents enter the 986–993. river. 18 Chemicals and their impacts

A plastic disc to replace a fish?

New legislation for chemicals has created a strong international demand for information on the bioaccumulation potential of organic micropollutants. Studies with live fish are costly and also need to be reduced to a minimum for animal welfare reasons. Our laboratory method successfully simulates passive uptake across fish gills. Jung-Hwan Kwon, Beate Escher

Many organic micropollutants accu- Pharmaceutical forerunners ] –2 mulate significantly in fish. This bio- Various laboratory methods have –1 [h accumulation is thus important not been developed to evaluate the –3 e,nom 135TriCB only for fish health and ecosystem passive absorption and elimination –4 integrity, but also for human health. of pharmaceuticals with the aid of Pyr –5 For the registration of new chemi- biological membrane models. One of BaP cals, manufacturers are required to these methods – the Parallel Artifi- –6

assess bioaccumulation in fish. cial Membrane Permeability Assay –7 (PAMPA) pioneered by Hoffmann- –8 Need for more rapid tests La Roche – has also been used for Bioaccumulation involves two path- organic micropollutants [1]. Unfortu- Elimination rate in fish log k –9 –9 –8 –7 –6 –5 –4 –3 –2 ways: nately, however, this method is not Permeability model E bioconcentration, i. e. direct accu­ suitable for particularly problematic PDMS Pampa log Pe [cm/h) mulation from ambient water, es- substances, as these are generally The results obtained with the gill model are pecially through passive diffusion poorly soluble in water. in close agreement with the elimination rates across the gills, We modified this method to simulate measured in vivo, with the exception of E biomagnification, i. e. accumulation the process occurring in fish gills. A ­substances whose elimination rate is in- via the food chain. polydimethylsiloxane (PDMS) mem- creased by metabolism e. g. benzo[a]pyrene, 1,3,5 trichlorobenzene (orange marked zone). Bioconcentration is generally evalu- brane – serving as a gill membrane ated using OECD Test Guideline 305. model – is placed between a pol- This procedure requires the killing of lutant-impregnated donor disc and enzymes isolated from fish liver to the 40 – 60 fish per compound tested. A a pollutant-free acceptor disc (both acceptor cell, so that the contribution single test takes 2– 3 months and can also made of PDMS). The decrease of metabolism can also be predicted. easily cost more than CHF 100,000. in pollutant concentrations is then However, the PDMS‑PAMPA system There is a pressing need for alterna- measured in the donor, together with can already be used for worst-case tive methods. the increase in the acceptor. How- assessment of bioconcentration po- ever, what determines the time re- tential and thus as an aid to decisions quired for equilibrium to be reached on whether animal experiments are on either side of the membrane is even necessary. i i i diffusion not through the membrane itself, but through the unstirred aqueous boundary layer that forms between the membrane and well- stirred water. In gills well supplied with oxygen, this layer is only about 20 µm thick. Simulating this in the laboratory requires the use of a spe- cial stirring system.

[1] Kwon J.-H., Katz L.E., Liljestrand Effective gill model H.M. (2006): Use of a parallel artifi- Using our experimental set-up, we cial membrane system to evaluate tested 14 hydrophobic chemicals [2]. passive absorption and elimination in The permeability values correlated small fish. Environ. Tox. Chem. 25, 3083–3092. well with the elimination rates meas- [2] Kwon J.-H., Escher B.I. (2008): A ured in vivo. The only exceptions modified parallel artificial membrane The stir disc is placed in one half of the glass cell. The entire glass were substances that are metabo- permeability assay for evaluating cell, with the PDMS membrane in the middle, is then mounted on a lized in fish and therefore have higher ­bioconcentration of highly hydropho- magnetic stirrer in which the discs are not just rotated but tumbled bic chemicals in fish. Environ. Sci. end-over-end. This ensures that only a wafer-thin water layer remains elimination rates than are predicted Technol. (in press). unstirred at the gill membrane. by the model. We now intend to add Chemicals and their impacts 19

A climate record preserved in dripstone

Stalagmites in limestone caves, which develop over thousands of years, can be used by researchers to study the past climate. Unlike Arctic ice cores, for example, they also provide long-term infor- mation on conditions in temperate and continental zones. However, high-precision extraction of gases from microscopic water and air inclusions in stalagmites is extremely challenging. Yvonne Scheidegger, Rolf Kipfer, Rainer Wieler1, Dominik Fleitmann2, Markus Leuenberger 2

As a result of seasonal variation in heating. We tested the method by A drip rates, stalagmites exhibit distinct analysing samples taken from a sta- growth layers, which can be precise- lagmite from Yemen, which is still ly dated. As stalagmites grow, minute active today. The temperatures cal- quantities of drip water and cave air culated accord well with the present are trapped inside. These water and cave temperature. However, they B air inclusions are promising climate still show large errors, as we have records, which remain largely unre- so far been unable to measure ab- searched. solute concentrations. We are cur- rently seeking to reduce the margin A Intact crystals of error by determining the amount Dissolved noble gases in water of water extracted from the sample inclusions provide a record of the manometrically, so that palaeotem- climatic conditions prevailing at the peratures can be determined even 50 µm time when they were enclosed in more precisely. Micrograph of a stalagmite from Oman. the stalagmite. This is because the A: Water inclusion, B: Air inclusion solubility of noble gases (neon, argon More luxuriant growth and xenon) depends on the tempera- 2000 years ago ture and salt concentration of the To study the gases from the air inclu- the cave. Comparison of the recent water and on the atmospheric pres- sions, the composition of present- and the ancient sample suggests sure during gas exchange. Applying day and 2000-year-old samples from that biological activity was higher a method familiar from groundwater the same stalagmite was analysed. in the past. The climate of this arid analysis, the ratio of gas concentra- Initial findings show that the main country must therefore have been tions can thus be used to determine components of the air occur at the more humid at that time. i i i the cave temperature that must have same levels as in the free atmos- prevailed when the water inclusions phere. However, trace gases – es- were formed. pecially CO2 – are markedly elevated The main difficulty involved in ex- compared with atmospheric concen- tracting the gases from the water trations. The carbon isotopic compo- inclusions is to avoid any mixing with sition is very light, suggesting that noble gases from nearby air inclu- the CO2 is of biogenic origin. This sions, since noble gases from the shows that the old air inclusions do air yield no information on the past indeed contain “old” cave air and climate. We have developed a meth- can be used as an indirect indicator od that makes it possible to extract of biological activity in the soil above noble gases from water inclusions while keeping to a minimum any in- terference caused by noble gases from air inclusions. To this end, the stalagmite material is crushed, with- out the individual calcite crystals being destroyed. This allows the air between the crystals to be released – but not the water inside the crystals. Only in the next step are the gases dissolved in this water extracted by

1 ETH Zurich The last 7000 years’ growth (approx. 20 cm) of a stalagmite from the Sofular Cave (Turkey). The entire formation 2 Bern University ­contains growth layers dating back 50,000 years. 20 Chemicals and their impacts

Arsenic and uranium in Greek groundwater In some regions of Greece, groundwater used for drinking contains elevated concentrations of arsenic and uranium. While uranium is below the guideline value in the areas studied, arsenic levels are above the new EU limit of 10 µg/l. Existing remedial measures now need to be rapidly expanded to ensure compliance with the tighter regulations, in force since January 2008. Ioannis Katsoyiannis and Stephan Hug

In view of its carcinogenic effects, iron oxide. The second step involves the EU, WHO and US limits for ar- 20 a biological sand filter, in which natu- senic in drinking water have been rally occurring bacteria oxidize dis- 15 lowered to 10 µg/l. This limit is ex- solved manganese to manganese ceeded in many regions of Europe 10 oxides, which are retained together

and elsewhere. In Greece, a transi- Arsenic [µg/l] Standard with the iron oxides. As(III) is oxi- 5 tional limit of 35 µg/l was applicable dized to As(V), but not removed, as until January 2008. In an EU-funded 0 the amount of the oxides formed is project, we studied the situation in 1 2 3 4 5 not sufficient to bind all the arsenic. 1 Before treatment two regions of Northern Greece. 2 After aeration In the third step, addition of Fe(III) 3 After biological oxidation salts results in arsenic sorption on 4 After Fe(III) addition Three times the limit 5 After sand filtration the additionally formed iron oxide In groundwater, arsenic occurs in Astotal unfiltered particles, which are removed by the Astotal filtered two forms: the dominant species in As(III) filtered sand filter in step 4. In areas with

oxic water is As(V), which is easier to Arsenic concentrations in groundwater from oxic groundwater containing As(V), remove. The main species in anoxic Malgara (Axios) after each treatment step. a facility comprising steps 3 and 4 water is As(III), which generally has would be sufficient. to be oxidized to As(V) to permit In laboratory tests and in pilot plants, removal. In two regions on the Ther- As(III)), 165 µg/l iron, 550 µg/l phos- we are currently developing sim- maic Gulf, we collected samples from phate, 235 µg/l manganese and pler methods for arsenic removal for 23 groundwater wells. The average 1.2 mg/l ammonium. At a multi‑step small-scale facilities. One promising arsenic concentrations for the two water treatment plant, which has option is the use of sand filters with regions were around 30 µg/l, with been installed in Malgara in 2005, iron filings, which continuously form values ranging from 10 to 70 µg/l. we studied the removal of arsenic dissolved Fe(II) and iron oxides in In the reducing groundwaters in the in collaboration with the local opera- aerated water, thereby continuously alluvial plain of the Axios and Lou- tors. In step 1, the water is aerated oxidizing and retaining As(III). i i i dias rivers, As(III) predominated and and dissolved Fe(II) is oxidized to uranium concentrations were low. In insoluble Fe(III), with formation of the oxic groundwaters of the karstic microscopic, suspended iron oxide region of Kalikratia, As(V) was the particles (“red-orange water”). In the dominant form and uranium concen- process, a small fraction of As(III) is trations up to 10 µg/l were found oxidized to As(V) and bound to the (WHO guideline value for uranium: 15 µg/l). Katsoyiannis I.A., Hug S.J. et al. (2007): Arsenic removal in four steps Arsenic speciation and uranium con- centrations in the groundwaters in In Malgara (Axios), the groundwa- Thessaloniki Northern Greece: Correlations with ter contains 20 µg/l arsenic (mainly Aksios redox indicative parameters and im- plications for groundwater treatment.

Kalikratia Science of the Total Environment The situation in Switzerland Katerini 383, 128–140. In Switzerland, the limit for arsenic in drinking water is still 50 µg/l, Katsoyiannis I.A., Zikoudi A., Hug S.J. but in practice, water suppliers want lower concentrations. In (2008): Arsenic removal from ground- ­areas where concentrations exceed 10 µg/l – particularly in the 20 km waters containing iron, ammonium, cantons of Ticino, Graubünden and Valais – the problem can gener- manganese and phosphate: A case Location of the two study regions in northern ally be solved by dilution with uncontaminated water. The use of study from a pilot plant unit in North- Greece: a) Axios, 30–40 km west of Thessa- individual contaminated resources would require arsenic removal ern Greece. Desalination 224, loniki and b) Kalikratia, 40–50 km south-east similar to that in Greece. 330–339. of Thessaloniki. Chemicals and their impacts 21

The psychology of sand filter use

Technological innovation is not in itself sufficient to solve real-world problems – solutions can only be effective if they are consistently and correctly applied in practice. This calls for campaigns tailored to target groups’ material, social and psychological situation. Taking the example of sand filters used for arsenic removal, we sought to identify the key require- ments. Robert Tobias, Hans-Joachim Mosler

Many problems concerning water Vietnam: supply and wastewater disposal can follow-my-neighbour be solved with the aid of innovative In order to assess the situation in technologies developed at Eawag Viet­nam, we conducted representa- Samuel Luzi, Eawag – or rather, could be solved, since tive surveys in villages around Hanoi households first need to be encour- and evaluated the responses statis- aged to install, use and maintain tically. It was shown that people’s these systems. This can be achieved behaviour is strongly influenced through promotional campaigns by that of their peers. Accordingly, devised and implemented by social sand filters are used by almost all scientists. households in some villages, and by scarcely any in others. Surprisingly, Arsenic in drinking water however, the filters are generally not Current estimates suggest that the rated as expensive and are not con- health of more than 100 million peo- structed because of arsenic in drink- Sand filter for iron and arsenic removal, used by rural households in ple worldwide is threatened by drink- ing water but to remove the non‑haz- the Red River Delta (Vietnam). ing water contaminated with arsenic. ardous but unpalatable iron content. Chronic exposure to arsenic concen- Maintenance is often not carried out trations of 50 µg per litre is enough frequently enough or is neglected al- These and other techniques can be to cause serious health problems together, even though the yellowish- used to ensure that effective inno- after 10 –15 years. The first sign of brown colour of the water and the vations are actually implemented on disease is a change in skin pigmen- reduced flow rate seem to remind the ground, thus contributing to the tation, which may be followed by respondents that maintenance is re- solution of real problems. i i i skin cancer and blackfoot disease – quired. a condition typical of chronic arsenic However, many people appear to be poisoning. Sand filters developed unaware of the importance of main- by Eawag can help to mitigate the tenance. To put the same point differ- problem of contamination: using ently, proper maintenance is carried this simple method, 80 % of the out significantly more frequently by arsenic content on average can be those respondents who emphasized removed by precipitation. However, the health benefits of the filter in the for a household, the effort involved in survey. installing and operating a sand filter is Based on these results, campaigns not insignificant. can now be developed to promote the construction and maintenance of sand filters. For example, to raise public awareness, the arsenic issue Sand filter could be highlighted by the mass Groundwater pump ­media. Another possibility would be to offer a water-testing service, with households paying to have samples Water storage tank collected and analysed. www.eawag.ch > Abteilung System­ To take advantage of the social forces anlayse und Modellierung > Gruppe Soziale Systeme revealed by the survey to be particu- Berg M. et al. (2006): Arsenic removal larly important, targeted efforts could from groundwater by household be made to help interested house- sand filters – comparative field study, With the aid of a simple sand filter, 80 % holds install and maintain sand filters. model calculations, and health bene­ of the arsenic content, on average, can fits. Environ. Sci. Technol. 40 (17), be ­removed from pumped groundwater in They would then serve as models 5567–5573. ­Vietnam. and instructors for other households. AquaticWater ecosystems as a

“Whenever I go to a new town, the first thing I need is a map,” says Rosi Siber (44). As an expert on geograph- ical information systems (GIS), she is the first point of contact at Eawag for anyone who needs to evaluate, rep- resent or obtain geographical data. She is currently work- ing with the Agriculture and Water Protection Group on Lakes, rivers and streams are complex habitats. the development of a model that shows which areas of It is essential to understand the workings of Switzerland are of particular relevance for inputs of pesti- these aquatic ecosystems if the goal of sustain- cides to water resources. As well as site-related factors able management is to be achieved – whether it and climatic data, the model incorporates information on is on the Yangtze River in China, on Lake Kivu in crops grown, pesticide use and other data. Naturally, it the heart of Africa, or on Lake Wohlen near Bern. habiis not possible to include every single field. However, tat At Eawag, methods and approaches are being the results will support the authorities in decisions as to developed to allow early detection of changes which zones require closer monitoring, also covering in these systems and in the organisms they small streams. In this project, Siber has benefited from ­support. Intact waterbodies are important not her knowledge of only for the preservation of biological diversity, ­agriculture, which but also in terms of the valuable “services” derives not just from they provide for humans – for example, safe- her experience in guarding water resources and water uses over her own garden but the long term. from the fact that she originally trained as an agricultural technical assistant. andShe subsequently re source studied biology at Constance Univer- sity and became ­interested in water through limnology. Previously, she had explored streams mainly as a canoeist. Her cheerful nature means that she is ideally suited for the dual role of researcher and GIS specialist that she has played at Eawag since 2002 – as well as being interested in data- bases and aquatic ecology, she enjoys working with ­people. In the Rivers of Europe project (page 31), she not only handled the data processing and provided a lot of behind-the-scenes advice but also co-authored the chapter on the Danube. Carsten Schubert (41) started out studying physics at Giessen University, but after two semesters he couldn’t see the point of calculating rocket trajectories and switched to geology. As he now recalls, “I hadn’t previ- ously had anything to do with rocks, but I was enthusias- tic from the very start.” He then turned his attention from hard rocks to softer deposits, ­analysing a sediment “At secondary school, my dream was to be a marine core from the Baltic ­biologist and to work on a ship for Greenpeace,” says Water as Sea fora his disserta- Christine Weber (33), who comes from the Emmental tion. The information region. At Bern University, she did indeed study biology. preserved in the However, her only dealings with fish were during an sample dates back ­internship at the Federal Veterinary Office, when she 10,000 years – was concerned with imports and exports of ornamental which provides the species. Her first contacts with Eawag came with a sub- link to environmental sequent internship in palaeoecology: at Kastanienbaum, research since the she investigated the evidence of past climate conditions occurrence of the provided by pollen heavy metals lead, zinc and cadmium in the core docu- trapped in lake mented the beginning of industrialization. In 1991, Schu- ­sediments. Having bert had an opportunity to join an expedition on the enjoyed this place- ­German research vessel “Polarstern”. He still has vivid ment, she later memories of this voyage – the moment the compass ­applied – success- habi tatneedle started spinning round, the telegram of congratu- fully – for a position lation from the Federal Chancellor, going swimming at as a doctoral stu- –1.7 °C and the celebrations on board when the ice- dent, to work on fish breaker had reached the North Pole. At the Alfred Wege- ecology and river ner Institute in Bremerhaven, Schubert subsequently ­rehabilitation as part wrote his doctoral thesis on Arctic Ocean sediments. of the Rhône-Thur ­After holding a fellowship at the University of British project. She is partic- ­Columbia, he spent four years at the Max Planck Institute ularly fond of research in the field. On one occasion, dur- for Marine Microbiology in Bremen. Here, Schubert and ing fieldwork on the Rhône, she was standing on two his co-workers were the first to demonstrate and pre- rocks near the riverbank when a squeaking water shrew cisely describe the mechanism of anaerobic methane oxi- approached and swam round her – an experience of dation by archaea and bacteria. Their paper published in ­nature which she will never forget. “I learn most about Nature in 2000 is still frequently cited. However, jaded by biology when I’m outdoors,” she says. But isn’t she and re sourcethe publications rat race, he considered moving to Italy, ­disillusioned when she sees how little really changes in where “the weather is fine and the food is good, but,” he practice following restoration projects? Weber demurs: admits with a smile, “I wouldn’t have earned anything.” “That’s not true – a great deal happens, but we are too Instead, he settled for a position at Eawag, where he impatient and the measures are frequently still very continues to work on methane – in Swiss lakes, rather ­localized.” She is clearly referring to all those who would than in the sea (page 34). A bad career move? “Not at pronounce the project a failure if salmon have not re- all”, says Schubert, a family man. “Here, I have the best turned to the Thur within a few years. As she points out, job in the world – with a degree of freedom that I proba- a variety of indicators – from the longer shoreline to the bly wouldn’t have in Germany.” growing numbers of recreational visitors – show that ­certain changes can already be precisely measured (page 30). “Other things just take longer than the four- year electoral cycle in politics.”

Aquatic ecosystems 25

Swiss-chinese Yangtzecooperation on the

As part of the Yangtze Freshwater Dolphin Expedition, Eawag collected water and sediment samples on a 1700-km-long stretch of China’s largest river. Analysis of these samples showed that while concentrations of most pollutants are in the same range as in other major rivers around the world, the loads are immense. Beat Müller, Michael Berg, August Pfluger1

Taming the waters of the Yangtze is a millennia-old project. Among the most important responsibilities of the early Chinese imperial rulers was to provide the country with beneficial rainfall, so as to ensure good harvests and sediment per year formerly transported to the East China avert famine, floods and droughts – disasters poignantly Sea, only about a third now reaches its destination. As a described in the works of the Nobel Prize-winning author result, the Shanghai Delta is gradually disappearing. To Pearl S. Buck [1]. The Yangtze, which together with the date, 1.4 million people have been displaced by the Three Yellow River to the north forms the cradle of Chinese civi- Gorges Reservoir, which began filling in 2003. In the fore- lization, is thus simultaneously loved and feared. seeable future, another 4 million people will have to be resettled, as the banks of the 600-km-long reservoir are Thousands of dams starting to erode in places. Since the 1950s, however, the taming of the Yangtze – the 6300-km-long artery on which some 350 million Gigantic diversion project people now depend – has assumed grotesque propor- Less well known is another large-scale project that has tions: the flow regime and suspended sediment trans- been under way since 2003. This is designed to trans- port have been profoundly altered by 45,000 dams in fer water northwards from the Yangtze river basin to the the entire catchment basin. Of these, 143 have a storage dried-up rivers of the thirsty industrial centres, where the capacity of more than 100 million m3, including the con- intensification of agriculture, desertification and demand troversial Three Gorges Dam. Of the 500 million tonnes of from the coal, cement and paper industries have led to increasingly acute water shortages. The world’s largest diversion project is to cost the equivalent of around EUR 45 billion and redistribute 50 billion m3 of water per year Mineral fertilizers, pesticides and untreated wastewater enter the Yangtze, which is also (mis)used for dumping refuse. Here, ­rubbish is fished out of the Three Gorges reservoir. (Photo: das-fotoarchiv.com/Xinhua). Top: Water samples were analysed 1 August Pfluger is the Director of the baiji.org Foundation, which has for more than 280 substances, with some tests carried out offices in Zurich and Wuhan. ­directly aboard one of the two research vessels. (Photo: baiji.org Foundation) 26 Aquatic ecosystems

First-ever survey by an international team The Yangtze Freshwater Dolphin Expedition was jointly organized by the Swiss baiji.org foundation and the Wuhan Institute of Hydrobiology. Under the auspices of the Chinese Ministry of Agriculture, the enterprise brought together researchers from six different coun- tries, including the authors of this article from Eawag. It was the first time that China had allowed an international team to carry out such a detailed study of the Yangtze. The main aim of the expedition was to investigate the reasons for the disappearance of the whitefin gives a striking account of this adventure, undertaken at dolphin (Baiji, Lipotes vexillifer) and the likewise threatened finless porpoise Neophocaena phocaenoides asiaorientalis. Among those supporting the project were the Swiss Agency a time when individual travel was still restricted in “Red for Development and Cooperation (SDC), the globally active Société Générale de Surveil- China”. [2] lance (SGS) Group, the Pictet bank and companies such as Canon, Victorinox and Katadyn. The crew of cetacean researchers from China, the US, Canada, the UK and Japan who combed the river for six weeks on two vessels found that Pilleri’s gloomy predic- – an average of 1500 m3 per second. For comparison, tion had come true: no whitefin dolphins were detected the mean discharge of the Reuss from Lake Lucerne is [3]. Each day, our team collected water samples and sus- 110 m3 per second. pended solids. These samples were analysed for more than 280 substances, either directly on board or in the Searching for the Baiji laboratories of the Swiss company Société Générale de In November 2006, Eawag took part in an international Surveillance (SGS) in Shanghai and Perth, and at Eawag. expedition searching for the whitefin dolphin in the Yang- This series of measurements – the most comprehensive tze. This now almost legendary creature, known by ever carried out on the Yangtze – provides a good picture the Chinese as “Baiji”, is comparable to the panda as a of water quality in one of the most important rivers in a national symbol. The Baiji was nearly chosen as a mascot country that is undergoing incredibly rapid change [4]. for the 2008 Olympic Games in Beijing. Our aim in joining A whitefin dolphin the expedition was to collect water and Surprising findings (baiji) in a Singapore particle samples on the 1700-km-long The results were somewhat unexpected: the concentra- aquarium. Photo: baiji.org stretch of the Yangtze from the Three tions of almost all the substances investigated were sur- ­Foundaition Gorges Dam to where the river enters prisingly low, although the Yangtze is considered to be the East China Sea, in order to investigate a possible one of the world’s most polluted rivers. However, anyone link between water quality and the disappearance of the who has seen the mighty Yangtze – which can be up to dolphin. As far back as 1979, the Bern zoology profes- 2 km wide, even on the middle reaches – will understand sor Giorgio Pilleri had predicted that the Baiji would be that this is not necessarily a contradiction: the immense endangered by the ongoing destruction of its habitat. inputs from agriculture and discharges of industrial efflu- Pilleri, who visited the country at the invitation of Chinese ents and – generally untreated – domestic wastewater are colleagues, was the first foreign researcher to see the highly diluted by the enormous masses of water flowing whitefin dolphin. In his personal scientific journal, he in the main channel. At the estuary, the yearly average discharge is around 32,000 m3 per second – more than 30 times as much as in the Rhine at Basel. Locally, how- ever, the quality of water in tributaries and of ground and hence drinking water is severely affected by the high lev- els of pollution.

Tow nets were deployed overnight to collect suspended particles from the river. The samples were then analysed for heavy metals, ­nutrients and organic industrial chemicals in the laboratory.

At 6300 kilometres, the Yangtze is the longest river in Asia. From the Three Gorges Dam to the Shanghai estuary, it flows over a distance of around 1600 kilometres. The difference in ­elevation along this stretch is barely 35 metres. Aquatic ecosystems 27

Heavy metals kg/day Zinc 10 000 Chromium 6300 Low concentrations – heavy loads. The high rates of flow in Arsenic 4600 the Yangtze are double-edged: Lead 3000 on the one hand, they ensure that Antimony 900 pollutants are so highly diluted that they rarely show acute toxic- Selenium 340 ity. On the other hand, the rela- Cadmium 75 tively low concentrations obscure Thallium 54 the fact that the total pollutant loads discharged into the East Mercury 20 China Sea are immense.

Over long stretches, the Yangtze is canalized by 15-m-high Heavy shipping traffic on the Yangtze probably contributed to the disappearance of the baiji. embankments, and inflows are regulated by locks. Natural seasonal flooding of the plains is thus prevented, and huge areas have been drained for agricultural use on the middle and lower reaches. In many places, groundwater One factor among many exchange and recharge is impaired, adversely affecting Although on the basis of our study it is not possible to rule the quality of drinking water. out synergistic effects of different chemicals, long‑term effects, or impacts of endocrine disruptors, the deteriora- 1500 tonnes of nitrogen per day tion of water quality in the Yangtze appears to have been Despite the low concentrations, pollutant loads from the only one additional adverse factor contributing to the Yangtze have a major impact on the East China Sea: inputs extinction of the whitefin dolphin and to the decline of the of more than 1500 tonnes of nitrogen per day, particularly Chinese sturgeon and an endemic porpoise. Other factors from mineral fertilizers and untreated household waste- certainly include the destruction of habitats, extensive water, are partly responsible for blooms of blue-green canalization, the cutting-off of side channels by dams and algae and for the increasingly common red tides. The the drainage of shallow lakes (nurseries for many fish spe- latter are due to the explosive growth of dinoflagellates cies), overfishing and unselective fishing methods, and (especially the alga Karenia brevis), which may be toxic to the heavy shipping traffic on the Yangtze. all forms of marine life, including humpback whales and As flow rates and hence chemical water quality vary dolphins. In addition, decaying algae cause oxygen deple- widely in the Yangtze over the course of the year, our data tion at the bottom of the sea, depriving benthic organisms represent merely a snapshot. However, comparisons with – a food source for many fish – of their habitat. earlier measurements demonstrate increases in concen- Heavy metal concentrations – though generally in accord- trations of nitrogen, metals and organic compounds. This ance with Swiss and European guidelines –multiplied by means that pressure is growing on the river ecosystem the total volume of water yield enormous loads pouring and the coastal waters of the East China Sea – and thus into the sea from the Yangtze each day: 4600 kg of ar- also on the quality of life for at least 350 million people. senic, 3000 kg of lead and 900 kg of antimony (see Box). The extension of a reliable network of monitoring stations These heavy metals, together with persistent organic and concerted efforts now need to be pursued by China herbicides and pesticides, enter the food chain and are at an interprovincial level. One possible model could be found in fish and shellfish. the programmes and measures adopted by the riparian states within the framework of the International Commis- sion for the Protection of the Rhine (ICPR/IKSR). i i i

2000

1500 [1] Buck Pearl S.: Die gute Erde (1931); Söhne (1933); 1000 Das geteilte Haus (1935). [t N/d] − 3 [2] Pilleri G. (1980): Forschungsreise nach China zum Studium NO 500 der Delphine des Chang ­Jiang (Yang Tze Kiang). Verlag des ­Hirnanatomischen Institutes, Waldau-Bern. 0 [3] Turvey S.T., Pitman R.L., Wang D. et al. (2007): First human- 1600 1200 800 400 0 caused extinction of a ­cetacean species? Biol. Lett; doi: km from sea 10.1098/rsbl.2007.0292. [4] müller B., Berg M., Yao Z.P., Zhang X.F., Wang D., Pfluger A.: Increase in nitrogen load from the Three Gorges Dam to the East How Polluted is the Yangtze­ River? (eingereicht) Sci. Tot. China Sea. ­Environ. www.iksr.org, www.baiji.org 28 Aquatic ecosystems

River ecology enhanced by experimental floods On a regulated section of the River Spöl in the Swiss National Park, artificial floods were used to create a more dynamic flow regime. This led to a marked improvement in the ecological status of the stretch below the dam. However, it took three years for an equilibrium to be established between the altered environmental conditions and the plant and invertebrate communities. Christopher T. Robinson & Urs Uehlinger

The flow regime, temperature and tions of the river, since both the water bed structure of many rivers world- released to maintain instream flows wide have been altered by over (1.2 m3/second) and the floodwater 45,000 large dams (more than 15 m (10 – 55 m3/second) comes from the high) worldwide. This regulation has bottom layer (hypolimnion) of the adversely impacted the biodiversity Livigno reservoir. In the first year of the rivers concerned. For of flooding, the moss cover on bed Habitat diversity this reason, criteria based sediments disappeared. Macroinver- has increased on flow and temperature tebrate richness and biomass, but considerably. regimes are playing an in- not density, were clearly reduced. creasingly important role in After the third year, algal biomass

restoration projects. Artificial floods and benthic organic matter persisted The artificial floods on the Spöl erode debris­ are now being used more widely to at a low level and macroinvertebrate cones that otherwise constrain the main simulate a more natural flow regime density was reduced. Specific mac- channel. in regulated rivers. roinvertebrate taxa showed different Since 2000, regime-based manage- responses to the floods: a reduction ment has been implemented on the or an increase in abundance, or an has shifted towards disturbance‑re- River Spöl in the Swiss National Park, increase followed by a loss after the sistant species, and spawning con- with one to three experimental floods third year. The number of fish redds ditions for brown trout have been released per year. This management used by brown trout increased four- substantially improved. measure provided an opportunity to fold over the study period because In the present case, it took three study the long-term effects of a flow of the increased porosity of bed sedi- years for the effects of the new flow regime shift on river ecology. ments. regime to unfold. The natural dynam- ics of the River Spöl have only been More fish redds Better adapted community partly restored, as residual flows The experimental floods had no ef- The large variation observed in algal are consistently low between each fect on the physicochemical condi- and macroinvertebrate biomass and flood. However, this compromise so- density over time indicates that the lution – the result of an agreement biotic communities were not in equi- among all stakeholders (National ) 2 20000 librium with the altered environmen- Park, hydropower generation, fisher- tal conditions during the first three ies) – has benefited the Spöl eco- 15000 years. When individual floods are system. i i i 10000 ­assessed, it can be seen that the

500 immediate effects on macroinverte- brates were 30 % greater at the be- 0 ginning of the series of floods than Protonemura spp.(no./m today. The new community structure

) 30000 2 is evidently more resilient to flood

20000 disturbance. The flood programme has improved Robinson C.T., Uehlinger U.: Artificial 10000 the ecological integrity of the regu- Floods Cause Catastrophic Regime lated stretch of the River Spöl below Shift in a Regulated River. Applied

Chironomids (no./m 0 Punt dal Gall dam. Habitat diversity Ecology, im Druck. 1999 2000 2001 2002 2003 2004 2005 2006 has increased considerably, moss Robinson C.T., Uehlinger U. (2007): cover – not typical of alpine streams Using artifical floods for restor- Changes in the abundance of stoneflies (Protonemura spp.) and ing river integrity. Aquatic Sciences ­chironomids in the Spöl over time. The artificial floods are indicated – has disappeared, the composition 65,181–182. by blue triangles. of the macroinvertebrate community Aquatic ecosystems 29

The sound of rivers

Although the sound of watercourses has never before been systematically stud- ied, acoustic “fingerprinting” can help to assess the ecological condition of alpine streams and rivers in particular. At the same time, the sound can be used to rate their aesthetic quality, adding an objective element to discussions of the value of watercourse diversity. Diego Tonolla, Klement Tockner, Berit Junker (WSL), Kurt Heutschi (Empa)

Since time immemorial, the murmur- arrangement of habitats and areas of ing, babbling, raging and roaring of increased sediment transport. watercourses has been described by Habitat-specific sound patterns are authors and poets. To date, however, clearly identifiable: riffles exhibit the sound of streams and rivers has a bimodal frequency distribution, not been the subject of systematic while steps display a peak in the research. We therefore decided to 160 Hz – 2 kHz frequency range. Lab- use methods from the natural and oratory experiments indicate that riv- social sciences to investigate how erbed roughness and water velocity the sounds of river habitats differ are key factors in sound generation. from one another, and whether changes in morphological quality can Attractiveness enhanced be detected acoustically. by sound To investigate the association be- Typical habitats tween visual and acoustic aesthetic Sound recording on the River Inn near Strada. Four typical river habitats were char- evaluation of rivers, we played back acterized hydromorphologically and various video sequences to a total acoustically: of 1079 people. The representative rates – below the legally specified E Pools: deep, slow-moving stretch- survey in German-speaking Swit- residual water volume – being rated es, zerland shows that the appearance as less attractive than stretches with E Riffles: fords, with swiftly moving and sound of restored river sections medium flow rates. Rates of flow water at the surface, are rated as clearly more attractive in the latter stretches are frequently E Runs: straight, non-turbulent than non‑restored stretches. The as- reduced as a result of hydropower stretches between pools and riffles, sociation is somewhat less marked generation. or channelized sections, when only the soundtrack of the Our project generated a lot of media E Steps: small vertical drops over video sequence is played back to re- interest. We now intend to develop boulders in the riverbed. spondents. The perception of river a simple tool for assessing the eco- In addition, underwater acoustic sound is thus influenced by visual logical integrity of surface waters. signals were continuously record- impressions. However, the way we The aesthetic value of landscape – ed along three stretches of river perceive the sound of a river is not hitherto appreciated purely in visual 8 –23 km in length (Thur, Tagliamen- only influenced by whether or not it terms – is to be augmented with the to in Italy, and North Fork in Mon- has been restored. Discharge also acoustic component. i i i tana, US). These recordings make plays an important role, with stretch- it possible to determine the spatial es of river characterized by low flow

Pool Run Riffle Step dB

Underwater sonograms for different habitats. Plane: time (seconds; 5-minute recording) and wave bands (20 Hz – 20 kHz); perpendicular axis: sound level (relative decibels). 30 Aquatic ecosystems

How natural is the rehabilitated River Thur? Does river rehabilitation actually lead to the development of more natural species com­ munities? Fish surveys in widened reaches of the River Thur have shown that, while habitat diversity is greater in large widenings than in canalized reaches, the fish assemblage ­structure cannot yet be described as near-natural. Christine Weber, Armin Peter

According to the contemporary large-scale widening projects were historical community composition, “Wild Map”, the Thur at Nieder- implemented. specialist species are now markedly neunforn about 150 years ago was In the winter and summer of 2005, underrepresented, while the Europe- a braided river with a broad gravel we collected samples by means of an chub – a tolerant species – is dom- bed. Around 1892, Wehrli counted a electrofishing from the three largest inant. Only individual specimens of total of 22 fish species in the diverse widenings (Gütighausen, Nieder- brown trout and sculpin were found river habitats. Dominating the com- neunforn, Pfyn) and five canalized in the catch (0.5 %). munity were the rheophilic barbel, reaches. We also produced accurate Habitat diversity can be increased by nase, spirlin and vairone. Also abun- maps of fish habitats with the aid large-scale river-widening projects. dant at that time were the brown of GPS. Monotonous flow conditions However, the weak response of the trout and sculpin – both cold-water (moderate depth, moderate flow ve- fish fauna reflects persisting defi- species. Each year, the Atlantic salm- locity) predominate in the canalized ciencies, such as low thermal heter- on and European river lamprey would reaches and the shortest widening ogeneity. In addition, the habitat con- migrate up the Rhine from the North (< 300 m), while shallow areas and dition of the Thur as a whole needs Sea to spawn. fast‑flowing waters occur frequently to be considered: 65 % of the lower in the two longer widened reaches. 90 km of the river is still morphologi- Shoreline length more In addition, the shoreline length is cally degraded, fragmented by weirs, than halved much greater along these reaches, or impaired by residual flows. Moreo- At the end of the nineteenth century, even though all the current shore- ver, the rehabilitated habitats may not long sections of the Thur were canal- line lengths are markedly lower than yet be fully recolonized. Monitoring ized for purposes of flood control and those seen in 1850. of the outcome should therefore be land reclamation. At Niederneunforn, continued for several years i i i the shoreline length was reduced Flood refugia from 4.5 km per kilo- We observed a rich fish community, This study was part of the Rhône-Thur River widenings metre of river to just with a total of 20 species; however, project, an interdisciplinary research pro- offer refugia 2 km. This measure there were no differences in commu- gramme funded by Eawag; the Swiss has lead to a dramatic nity composition or individual density Federal Institute for Forest, Snow and that canalized reduction in exchang- between the canalized and widened Landscape Research (WSL); the Labora- reaches lack. es with the adjoining reaches. Fish abundance is gener- tory of Hydraulics, Hydrology and Glaciol- ogy (VAW) of the ETH Zurich; the Federal land, which are im- ally low, although more fish are found Office for the Environment (FOEN); and portant for river ecology. There is a in well-structured habitats – regard- the Federal Institute of Technology, lack of flooded areas, and inputs of less of whether these are situated Lausanne (EPFL). The original project woody debris decline. Despite the in ­canalized or rehabilitated reaches. was completed at the end of 2005 (see extensive modification, flooding con- The highest fish densities occur in Eawag Annual Report 2006), and an EPFL river engineering module in 2007. tinued to cause significant damage deep backwaters, which are found The topic of rehabilitation is being­ pur- (events of 1965, 1977 and 1978). only in the rehabilitated reaches. sued in a follow up project involving the The 1990s saw a paradigm shift in These serve as refugia during floods same partners – “Integrated river basin river engineering, and 15 increasingly or in the winter. Compared with the management”. (www.rivermanagement.ch).

Wehrli E. (1892): Fischleben der kleinen around 1850 approx. 1900 to 2002 2005 thurg. Gewässer – Beitrag zu einer Fauna des Kantons Thurgau. Mit- teilungen der Thurgauischen Natur- forschenden Gesellschaft 10, 61–104. Weber C., Schager E., Peter A.: Habitat

0 200 400 m diversity and fish assemblage struc- ture in local river widenings: a case study on a Swiss river; accepted in The changing face of the Thur at Niederneunforn. Historical topographical maps of the river have been digitized, and GPS River Research and Applications. field mapping was carried out in 2005. Aquatic ecosystems 31

European rivers under pressure

The Danube alone drains parts of 18 different countries and thus is the world’s most “international” river. For the implementation of the EU Water Framework Directive, Europe’s hydrogeographical, ecological and cultural diversity represents a major challenge. The development of river basin management plans required by the Directive should be facilitated by the Rivers of Europe project. Klement Tockner1, Urs Uehlinger, Christopher Robinson, Diego Tonolla, Rosi Siber, Fabian Peter

In the Rivers of Europe project, these include the Frome in the UK, land) are not indigenous (see map). under the direction of Eawag, the the Tagliamento in Italy, and the Ural At the same time, up to 40 % of the ecological status of 165 European in the border regions of Russia and original native fishes, e. g., in the riv- river basins is being described for the Kazakhstan. Accordingly, these rivers ers of the Iberian Peninsula, are now first time. These basins drain almost are reference ecosystems of conti- extinct. Particularly affected are fish- 8 million km2 – more than 70 % of nental importance. Most of Europe’s es that migrate over long distances, the total area of Europe. Seven of the river basins are heavily affected by such as the sturgeon 10 largest catchments are in Eastern human activities. Natural flows in and Atlantic salmon. 40% of native Europe, including, for example, the Europe’s waterways are disrupted In the case of crayfish, fish species have Pechora and the Dnieper – two rivers by over 6000 major dams. Pressures the situation is even disappeared from that are still widely unknown. With on surface waters will intensify as more dramatic. As well this database, it will be possible for a result of the predicted increase in as six native species, the rivers of the the first time to compare the status extreme flow events and the grow- seven alien species are Iberian Peninsula. of and risks to biological diversity ing demand for water by agriculture. now found in Europe. across the whole of Europe. This in- By 2070, the area of river basins with Many river basins that were naturally formation provides an essential basis a massive water deficit is expected free of crayfish are now dominated by for the planning of protection and to double, from 1.3 million km2 today introduced species. Overall, Europe’s management strategies, as required (18 % of the total area under consid- natural freshwater fauna has become under the EU Water Framework Di- eration) to more than 2.5 million km2. increasingly homogenized. rective. The pressures facing European Growing homogenization freshwater habitats are indicated Few remaining reference In some cases, the proportion of non- by the sharp decline in the biologi- ecosystems native species is already very high. cal diversity of Mediterranean river Across Europe, only a small number For example, up to 50 % of the fish basins (Iberian Peninsula, Italy, the of rivers are still in a relatively natural species found in the Ebro (Spain), the Balkans and Turkey), which originally state. Besides rivers in the far north, Seine (France) and the Shannon (Ire- harboured a particularly rich fauna and flora, meriting protection. For ex- ample, 45 % of the fish and almost 30 % of the amphibian species of the Iberian Peninsula are endemic to – i. e., found exclusively in – this region. At the same time, these areas are particularly exposed to the impacts apping Peter, D. Tonolla F. M of climate change, such as reduced streamflows, land-use changes and the spread of alien species. For this reason, these rivers should have top priority in the development of pan-

North Sea European conservation and restora-

Atlantic Ocean tion projects. i i i

Caspian Sea

Introduced species (%) No data 0 Black Sea 1 – 5 1 6 – 15 Eawag and Leibniz Institute of Freshwater 16 – 25 Ecology and Inland Fisheries (IGB), Berlin 26 – 35 > 35 Mediterranean Sea Tockner K., Robinson C.T. Uehlinger U. (2008): Rivers of Europe. Elsevier. Proportions of introduced fish species in Europe’s river basins. 32 Aquatic ecosystems

Species boundaries set by the environment At least 24 whitefish species are known to occur in Swiss lakes. Studies in Lake Neuchâtel have now demonstrated the presence of intermediate forms, which coexist with the known species but are not commercially fished or actively managed. The development and merg- ing of species can be significantly influenced by natural or human-induced changes in the environment. Pascal Vonlanthen, Denis Roy, Alan Hudson, David Bittner, Carlo Largiadèr, Ole Seehausen

Since the recolonization of the Alpine Intermediate forms rarely What is a species? region after the last ice age, white- fished for Various concepts of a species are found fish have differentiated into a large For the first time ever for whitefish, in evolutionary biology. What they all number of distinct species in Swiss we used genetic and morphological have in common is that populations of lakes. As they have become special- methods to study depth distribu- organisms are assigned to different spe- ized to different niches, the popula- tion. The results show that Lake cies if they coexist in nature over many generations in the same habitat without tions have no longer interbred free- Neuchâtel actually harbours not two genetically merging. Numerous species ly, even though in some cases they whitefish species, but an ecological, hybridize occasionally but remain differ- are not geographically isolated from morphological and genetic continuum entiated if mechanisms exist to restrict each other. of populations adapted to different gene flow. The definition of a species water depths and in which the two as a group of individuals not capable of interbreeding with members of other Palées and bondelles species originally described form just species is a popular misunderstanding of In Lake Neuchâtel, only two white- the extremes. To date, ecological iso- species concepts. fish species have been distinguished lation mechanisms have prevented to date – a fast-growing species the various forms from fully merging k n o w n a s “p a l é e” ( Coregonus palaea) into a single, homogeneous species. our understanding of how environ- and a slow-growing spe- The most important mechanisms at mental changes affect the origin Knowledge of cies called “bondelle” work here are probably specialization and loss of whitefish species, we how whitefish (Coregonus candidus). to different feeding niches and adap- have started to evaluate historical These two species differ tation to different spawning depths. ­data series. i i i species emerge in several ecologically However, the selection pressures or disappear relevant morphological do not currently appear to be strong characteristics, such as enough to lead to complete genetic is essential to Palée (Coregonus palaea), the number of gill rakers, isolation of the whitefish species. Depth of catch: 2 m optimize fishing but also in their selec- Our data suggest that the function- and conservation tion of spawning habitat. al diversity of whitefish responds regulations. Palées tend to spawn in ­directly to changes in lake ecology. shallows early in Decem- If the niche structure collapses, spe- Intermediate form, Depth of catch: 30 m ber, while bondelles tend to spawn cies diversity can be lost within a in deeper waters (below 50 m) and few generations through increased later, in January. However, a few genetic mixing. We suspect that the publications and the experience of lack of oxygen in deeper waters dur- Bondelle(Coregonus candidus), Depth of catch: 60 m local fishermen suggested that inter- ing the decades of lake eutrophica- mediate forms could also occur. tion brought the species ecologically closer together and led to genetic

assimilation. It is conceivable that 0 10 20 30 40 35 330 the recovery of Lake Neuchâtel in re- Length [cm] cent times has re-established some 33 Examples of whitefish caught in Lake 290 of the original niche structure, and ­Neuchâtel (Photos: P. Vonlanthen and 31 that the whitefish are now beginning A. Hudson). 250 29 to differentiate once again. Selection 210

No. of gill rakers by fishing may also play a role: for 27 www.fishecology.ch

Length at 3 years [mm] at 3 years Length economic reasons, the fishermen 25 170 Seehausen O., Takimoto, G., Roy, D., 0 50 100 0 50 100 fish specifically for either the larger Jokela J. (2008): Speciation reversal Depth [m] Depth [m] palées or the smaller bondelles; the and biodiversity dynamics with hy- bridization in changing environments; Two morphological characteristics of Lake Neuchâtel whitefish plotted intermediate forms are thus inad- Molecular Ecology 17, 30–44. against depth of catch: number of gill rakers (left) and size (right) vertently spared. In order to improve Aquatic ecosystems 33

Hard workers and cheaters in microecosystems Interactions between species have long been a central issue in ecology. However, little research has been devoted to the consequences arising for ecosystem processes. These processes could be dramatically altered by the loss of indigenous species or the invasion of alien species – a previously neglected aspect of the current biodiversity crisis. Sonja Raub, Christian Dang, Françoise Lucas, Eric Chauvet, Mark Gessner

It is only possible to assess the Asymmetric interactions and a 5 b 0.4 significance of biodiversity for eco- unaffected decay rate 4 system processes if the interactions In the mixed microcosms, the bac- 0.3 of various species within a biological teria had negative effects on the 3 community are understood. In our fungi, with fungal biomass produc- 0.2 experiments, we used a model sys- tion being on average 29 % lower 2 0.1 tem to observe the decomposition than in pure fungal microcosms. The 1 Fungal biomass [%] of leaf litter by bacteria and fungi – a strength of this inhibition did not de- Bacterial biomass [%] 0 0 1 1 2 2 1 2 2 1 1 1 2 2 2 2 F F F B B B B B process that is just as vital in many pend on which bacteria and fungi had B B B B B B 1 1 1 1 1 1 2 2 2 2 F F F F F F F F F rivers as it is in forests. Our aim was been combined (Fig. 1a). Conversely, B Fungi Bacteria to investigate the interactions occur- the fungi stimulated the bacteria in Mixed communities Mixed communities ring between bacteria and fungi: are one of the two mixed communities there any synergies, is the relation- (Fig. 1b). Presence of the bacteria Fig. 1: Biomass production of fungi and bacteria in microcosms, ­expressed as a percentage of the amount of litter initially present. ship neutral, or does antagonism pre- did not affect the rate of litter decom- Bacteria inhibit fungal growth in mixed assemblages (a) and, con- vail? And what are the consequences position (Fig. 2). Rather, the bacteria versely, can be stimulated by fungi (b). for the rate of litter decomposition? are cheaters that take advantage of the industrious fungi, whose degra- Decomposition simulated dation activity makes leaf litter avail- necessary to take all key ecosystem in microcosms able as a resource to their bacterial processes into account in assessing We first isolated from a river six bac- competitors. the ecosystem-level impacts of com- terial and six fungal species that had munity changes resulting from bio- colonized natural leaf litter. In the Comprehensive assessment diversity loss or the invasion of alien laboratory, these species were then needed species. I I I combined to form new communities It thus appears that even in a highly and allowed to grow on sterile alder simplified system, interactions in litter in microcosms for 10 weeks. microbial communities can simul- We studied pure bacterial and fun- taneously give rise to synergistic, 60 F1 F F F B B B gal communities, each consisting of antagonistic or neutral effects, de- 1 2 1 2 1 2 45 F2 three or six species, and also mixed pending on which ecosystem proc- F1B1 F2B2 communities, each comprising three ess (in this case, litter decomposition 30 bacterial and three fungal species. or biomass production by bacteria C2 B B1B2 B1 2 In addition, we used non-inoculated and fungi) and which community is 15 C2 microcosms as controls. observed. It would therefore seem Litter mass loss [%] 0 Controls Pure Mixed assemblages assemblages

Fig. 2: Microbial litter decomposition in ­microcosms: despite their effects on litter- degrading fungi, bacteria make neither a ­positive nor a negative contribution to litter decomposition.

Raub S. (2007): Effects of fungal and ­bacterial interactions on leaf decom- position in stream microcosms. ­Master’s Thesis, UNESCO-IHE/Delft Precisely defined quantities of alder litter were inoculated with fungal and bacterial com- University of Technology, Nether- munities in simple microcosms (left). Growth of the cultures was then observed in a climate lands. chamber (right). 34 Aquatic ecosystems

Wohlensee: lake flatulence and global warming As a greenhouse gas, methane is 25 times more potent than carbon dioxide. Accordingly, methane emissions from reservoirs are more significant then was previously assumed. On the Wohlensee, Eawag has studied how – and how much – methane from the bottom of the reservoir reaches the atmosphere. The emissions are roughly equal to those pro- duced by 7000 Swiss cattle. Tonya Del Sontro, Torsten Diem, Carsten Schubert

The construction of dams and the the surface. However, in shallow for tropical reservoirs (300 mg/m2 flooding of vegetated areas can lead waters – characteristic of most of the per day). Annual methane emissions to increased emissions not only of world’s lakes – methane in bubbles from the reservoir as a whole were carbon dioxide but also of methane typically reaches the atmosphere, estimated to be approx. 780 tonnes. – a greenhouse gas with a global and from a depth of 10 metres the For comparison, one cow produces warming potential about 25 times proportion is around 50 %, depend- 115 kg of methane per year, and the greater than that of ing on bubble size. total Swiss cattle population about From a water depth CO2. While little is 80,000 tonnes. of 10 m, about half known about the pa- High organic matter load of the methane rameters controlling The Wohlensee is a hydropower Tracking methane bubbles methane emissions reservoir, built in 1920 by the im- with a microphone reaches the from reservoirs, ebul- poundment of 15 km of the River Emissions from the reservoir via dis- atmosphere via the lition (bubbling up) ap- Aare downstream from Bern. It has a solved methane at the outflow and lake surface. pears to be the most maximum depth of 18 m and an area diffusion at the surface are one or effective pathway for of about 2.7 km2. The plant is a run- two orders of magnitude smaller than methane transport from the sedi- of-the-river system: all of the water releases via ebullition. Therefore, ment to the surface. Bubbles protect flowing into the reservoir flows out to quantify bubble fluxes more pre- the gas inside from being oxidized, as without restriction. The short resi- cisely, we are using a hydroacoustic generally occurs to dissolved meth- dence time (around 2 days) enables method. In addition, we are measur- ane. As bubbles rise in the water the water to remain oxic and mixed ing atmospheric methane concentra- column, gas exchange is known to throughout the year. However, also tions above the Wohlensee. i i i occur, and in deep lakes bubbles may during most of the year, methane dissolve completely before reaching bubbles can be seen reaching the surface in many parts of the reser- voir. This is largely due to the large amounts of organic matter carried by the Aare.

Equivalent to 6780 cattle A year-long study revealed that, ­despite its small size, this reservoir is a large methane emitter. Dissolved methane concentrations increase by an order of magnitude from the beginning of the reservoir to the dam, indicating intense methanogenesis. Using specially designed gas traps – This study was funded by the SNF and essentially inverted funnels – we car- is now part of the MAIOLICA project, sponsored by the Competence Center ried out ebullition surveys across the Environment and Sustainability (CCES): reservoir. Average methane emis- http://www.cces.ethz.ch/projects/clench/ sions from the Wohlensee to the MAIOLICA atmosphere via bubbles were found Ostrovsky I., McGinnis D.F., Lapidus L., 2 to be 792 mg/m per day. This is an Eckert W. (2008): Quantifying gas order of magnitude higher than the ­ebullition with echosounder: the average for other reservoirs in tem- role of methane transport by bubbles 2 in a medium-sized lake. Limnol. Retrieving methane traps – inverted funnels which capture the gas as perate regions (20 mg/m per day) Oceanogr. 6, 115–118. it rises through the lake. and is even higher than the average Aquatic ecosystems 35

Lake Kivu: time bomb or energy resource?

For some years, Eawag has been keeping a watchful eye on Lake Kivu in East Africa, where danger lurks in the form of billions of cubic metres of dissolved gases in the deep waters. Controlled exploitation of methane could now offer a dual benefit – ensuring secure power supplies in the region and reducing the risk of a deadly gas eruption. Martin Schmid, Natacha Pasche, Lukas Jarc, Alfred Wüest

Lake Kivu, which straddles the bor- In the long term, power generation is der between Rwanda and the Dem­ planned to reach 100 – 300 MW – a ocratic Republic of the Congo, is in huge increase over the country’s cur- many ways one of the world’s most rent total installed capacity of around fascinating waterbodies. Attention 30 MW. has focused largely on the vast quan- tities of gas stored in the depths of Stability of stratification the lake – around 300 km3 of carbon The exploitation of methane could, dioxide and 60 km3 of methane. If however, also have undesirable con- these gases were distributed over sequences, if the stable stratification the surface of the lake, they would of the lake were disturbed or an in- form a layer more than 100 m thick. crease in the flow of nutrients from the deep to the surface waters led Gas concentrations rising to marked eutrophication. Eawag has The dissolved gases pose a hazard, now developed a numerical simu- as they could erupt from the lake, lation model making it possible to causing a catastrophe. In 1986, an predict such effects under various eruption of gas from Lake Nyos in methane recovery scenarios. The re- Studies of tributaries are also required in order to assess nutrient Cameroon claimed 1800 lives. Al- sults of these modelling calculations ­cycles in the lake. though the probability of such an are being used by the Rwandan and event occurring on Lake Kivu is very Congolese governments to specify research on the ground is sometimes low at present, it is likely to increase guidelines for licensees involved attended by unexpected difficulties since our measurements show that in methane extraction. In addition, – for example, having spent a few gas concentrations are rising. But Eawag is participating in the develop- days in Bukavu, you may encounter methane is also an important re- ment of a programme for monitoring a customs official who is unwilling source: because Rwanda in particu- whether the effects of methane ex- to let you back into Rwanda because lar lacks other sources of energy, the ploitation on the lake are in line with the rules have changed again and government has granted licenses for projections. your documents are incomplete. You pilot power plants, which are to begin Methane production in Lake Kivu is may also be caught in a storm when operating towards the end of 2008. directly dependent on internal nutri- you are out on the lake in a pirogue. ent cycles. In cooperation with the However, these problems pale into Institut Supérieur Pédagogique de insignificance beside the idyllic land- Bukavu (DRC) and the National Uni- scape, richly varied experience and versity of Rwanda, Eawag is studying fascinating scientific results. i i i and quantifying nutrient inputs from external sources and nutrient fluxes within the lake.

Adventurous research Initial analysis of sediment cores Schmid M. et al. (2005): Weak mixing indicates that sedimenting mate- in Lake Kivu: new insights indicate rial has undergone massive changes increasing risk of uncontrolled gas over the past 40 years. This could eruption. Geochemistry, Geophy- be partly attributable to strong popu- sics, and Geosystems 6/7, Q07009, doi:10.1029/2004GC000892. lation growth in the region; at the Schmid M. et al. (2004): How hazardous same time, we suspect that biologi- is the gas accumulation in Lake Kivu? cal food chains in the lake have been Arguments for a risk assessment significantly affected by the intro- in light of the Nyiragongo Volcano eruption of 2002. Acta vulcanologica Sediment traps collect sinking algae – one of duction of a sardine species from 14/15 (2002–2003), 115–121. the factors in the lake’s nutrient cycles. Lake Tanganyika in the 1950s. Our Urban water management

Wat “I have an affinity for water,” says geographer Monika er in Schaffner (32). When she was studying hydrology at Bern University, she chose the River Aare and water supply systems in Nepalese villages as the topics for her dissertation. Her interest in Nepal goes back to her child- hood, when she spent some time there, as her parents In the countries of the North, the problem of were involved in development assistance. It was natural disposing of human wastes is generally solved for her to choose a water-related subject for her doctoral simply by flushing the toilet. But in many thesis, too. Collaboration with Eawag – which had begun countries of the South, the situation is quite during her earlier studies – was also a logical step: different: inappropriate management of waste- “Anyone in Switzerland who does aquatic research ends water and faecal sludge poses acute risks to up working with Eawag,” says Schaffner with a smile. human health andurban the environment. As 2008 has As part of the North-South programme of the National areas been declared International Year of Sanitation Centre of Compe- (IYS) by the United Nations, this year’s account tence in Research of our activities in this sector focuses on projects (NCCR), she partici- that aim to provide sustainable sanitation pated in a study of solutions. Below, we spotlight just a few of the nutrient flows on numerous scientists who have been involved the Tha Chin River in in our research efforts. Thailand. Rather than considering only individual sources, a model was devel­ oped to analyse flows throughout the river basin (page 46). “This kind of integrated approach appeals to me,” she says. “I like the fact that Eawag is committed to solution- oriented projects as well as fundamental research.” So will her thesis provide concrete benefits for Thailand? Schaffner warns against inflated expectations. Thanks to this study, she says, it is now known that aquaculture, not pig farming, is mainly responsible for (excessive) inputs of nutrients in the Tha Chin basin. Possible ways of tackling the problem have been identified in a dis- sertation, but the question of how rapidly any measures can be implemented is completely open. Accordingly, the researcher will be spending the next few months at Eawag preparing a number of publications and will also be travelling to Thailand again to present her findings to the authorities. Having completed her Master’s in Civil Engineering at the University of British Columbia, Elizabeth Tilley (28) came to Eawag for a six-month internship. As she had already worked on the recovery of nutrients from waste- water during her studies and in her dissertation, her input was particularly welcome for the research group that had been con- cerned with urine source separation in the cross-cutting Ticino-born microbiologist Adriano Joss (42) financed Novaquatis project his studies largely by working as a white-water kayaking from 2000 to 2006. instructor with the Zurich Academic Sports Associa- Previously, Tilley had tion. Now, however – as a father of two daughters – he Wat er onlyin been familiar has little time to indulge his passion for being on (and with Nomix toilets occasionally under) water. Joss chose to study biology and related technolo- because he has always been fascinated by insects and gies from scientific the sometimes sophisticated strategies they use for publications. “Then locomotion and suddenly,” she says, defence. In addition, “it all came to life, at Eawag and especially in the new with their short life Forum Chriesbach building, where these facilities have cycles, insects can been installed. For me, working with these pioneers of adapt evolutionarily urine source separation was a great opportunity.” Now – more rapidly than, that Novaquatis has been completed, she is working on say, tortoises – to another project: in the Department of Water and Sanita- new (environmental) urban areastion in Developing Countries (Sandec), she is involved in conditions. Joss pilot studies and further development of the Household- finds this problem- Centred Environmental Sanitation (HCES) approach. This oriented behaviour planning tool is used, in consultation with stakeholders, attractive: “I’m to seek sustainable water supply and sanitation solutions motivated to carry at the household and neighbourhood level, especially out research where I can see knowledge feeding into in the rapidly expanding cities and slums of developing practice.” He originally came to Eawag as a doctoral countries (page 39). Tilley is no newcomer to this type of student in 1999, working on the fermentation of organic work: she had already managed a project sponsored by wastes, and has retained his interest in biotechnological the Canadian International Development Agency, which processes ever since – although he is now mainly con- was designed to improve sanitation in Mexico. As an cerned with wastewater rather than solid wastes. As part ­engineer, she finds it very rewarding to be part of the of the team led by Hansruedi Siegrist, he is investigating, highly international team at Eawag, with a wide variety for example, how combined nitrogen can be converted of individual backgrounds: “Although everyone speaks to gaseous nitrogen without the addition of a carbon good English I sometimes miss the Canadian accent source (page 48). This process, involving so‑called anam- from back home, but I’ve never regretted joining Eawag.” mox bacteria, plays an important role in nature within the global nitrogen cycle. However, it has not previously been implemented successfully in a reactor. “Now,” Joss is convinced, “we have found a robust solution, in collaboration with wastewater treatment plant operators and a manufacturer of special sensors.” The process is intended to make treatment plants more efficient – and the results of initial full-scale tests have increased Joss’s confidence. Nitrogen emissions are also problematic in many other settings – for example, on livestock farms where slurry cannot be directly utilized. “Could the anam- mox process be used there, too?” he wonders.

Urban water management 39 stakeholdersTurning intoparticipants People who are involved in decisions on how sanitation is to be improved in a neighbourhood or community will help to ensure the long-term success of the measures adopted. Eawag has therefore developed a planning approach that gives a key role to the households concerned. Pilot projects designed to test this approach have been successfully launched at six sites. Christoph Lüthi, Elizabeth Tilley

2008 has been declared International Year of Sanitation (IYS) by the United Nations, since clean drinking water and hygienic disposal of wastewater and excreta are essential to human health, dignity and development. Without improvements in basic sanitation, none of the E Experience has shown that importing industrialized- Millennium Development Goals can be achieved. In- world models of sanitation is neither appropriate nor sus- sanitary conditions have a direct impact on child mortality, tainable, e. g. in regions where water is too scarce for poverty and school attendance. waterborne sewage systems to be implemented. E Stakeholder involvement is vital to enable ownership Rapid urbanization and achieve cost recovery. This year, for the first time, the majority of the world’s E There is a lack of integration between the various com- population will be urban. African and Asian cities, in par- ponents of environmental sanitation: excreta, wastewater, ticular, are growing at breakneck rates. Most of the new solid waste and storm water are managed by means of city dwellers live in unplanned settlements – favelas, separate systems, often run by different people. Better bidonvilles or bustees. Here, “on-site sanitation” is the use of synergies can lead to more sustainable and cost- norm – if any facilities exist at all. Yet despite pit toilets effective solutions. being the reality for the vast majority of the developing E Growing pressures on the environment and on water world’s urban population, policymakers still focus almost resources make it essential that wastewater and nutrients exclusively on sewerage networks and centralized sys- in wastes should be recycled. tems designed without the participation of stakeholders. E “Business as usual” is often not sustainable even in This conventional thinking needs to be challenged, for the industrialized countries: the use of water of drinking qual- following reasons: ity to transport human excreta is extravagant and wasteful with regard to valuable nutrients.

Joint planning efforts can dramatically improve urban sanitation and ­increase the quality of life. Top: Rudimentary latrine in Dodoma, ­Tanzania. Bottom: HCES planning workshop in Curitiba, Costa Rica. 40 Urban water management aji na Ufanisi (Nairobi) M

ures to be implemented are closely based on the ­actual needs and means of users – especially women, who ­often make basic decisions on personal hygiene and envi- ronmental sanitation. The approach also focuses on sus- tainability: environmental sanitation problems are to be addressed as close to the source as possible, resources are to be conserved and waste is to be reduced.

Testing the HCES approach In 2007, Eawag began testing the HCES planning ap- proach in pilot projects at six sites – in Costa Rica, Burkina Faso, Kenya, Tanzania, Laos and Nepal. In each case, Communal sanitation block with toilet and shower facilities and a water kiosk in the Kiambiu cooperation was initiated with local partners, such as the ­informal settlement of Nairobi (Kenya). The Waruku community has opted to build a similar Latin American Faculty of Social Sciences (FLACSO) in block, and construction was completed in March 2008. Costa Rica, the CREPA research institution in West Africa, the Public Works and Transportation Institute in Laos and “Maji na Ufanisi” (Water and Development, an NGO) in Progress in sanitation has been hindered by a number of Kenya. In contrast to local administrations, which often factors: lack expertise, capacity and resources, research institutes E Responsibilities for sanitation are fragmented at the or NGOs tend to offer more flexibility and have better- national and local level. In some African countries, for ex- trained personnel, with strong connections to the com- ample, as many as four different ministries share respon- munities in which they work. sibilities for water and environmental sanitation. All the HCES launching workshops held to date have E In the public sector, low budgetary priority is accorded proved successful, generating lively debate and producing to sanitation and hygiene. concrete results. The success of these events was largely E There are major human resource and capacity gaps at due to the following factors: the local level. E A good mix of stakeholders (including community groups, senior administrators and religious leaders, etc.). Developing alternative approaches E Gender balance in community representation. In response to these problems, a new approach was de- E An appropriate space for the community to voice its veloped – under the guidance of Eawag – by the Environ- concerns. mental Sanitation Working Group of the UN Water Supply E Careful preparation. & Sanitation Collaborative Council (WSSCC). The House- E Avoidance of bureaucratic and technical jargon in all hold-Centred Environmental Sanitation (HCES) approach ­materials and presentations. places the household and neighbourhood at the core of the planning and implementation process. Decisions on Assembling components into systems determining the type of environmental sanitation meas- Those responsible for improving environmental services require detailed information. Municipal officials, urban planners and other decision makers can only fulfil their new roles if they are trained to implement household- Appropriate communal sanitation blocks centred approaches and if they receive the necessary In the densely populated slums of Waruku in Nairobi, one unhygienic “toilet” is currently technical and organizational support. Currently, there- shared by an average of 60 people. Faced with this situation, as Eawag project manager Christoph Lüthi recalls, “We thought every family would want their own toilet as soon fore, we are developing a “Compendium of Sanitation as possible.” But in line with the key requirement of the HCES approach – not to define Systems and Technologies” to facilitate a key step in the a single solution as optimal in advance – things turned out quite differently. Lüthi says: HCES process – the identification of different sanitation “People saw that they lacked not only the money but also the space and affordable water options. for a large number of private toilets.” Accordingly, a delegation from the community visited The Sanitation Compendium is divided into five sections: a communal facility in another part of the city, and were impressed by what they saw. Maji na Ufanisi (local NGO) has now completed a sanitation block including not only toilets but User Interface, Collection and Storage, Conveyance, also showers, and a kiosk selling affordable drinking water. The block has created jobs, and its maintenance and continued operation are assured by the low rates charged for users. Around 1000 residents now have access to basic – but hygienic and sustainable – sanitation, with a corresponding increase in quality of life. Urban water management 41

Treatment, and Use and/or Disposal. Rather than being offered ready-made “packages”, users can select one or more options from the various sections to build an entire system that is optimally adapted to local conditions and Input Type of Collection Emptying Use/Disposal ensures sustainable management of wastes and waste- Toilet and Storage and Transport water. By way of example, a system being considered in S1 Single Pit Faeces Faeces S2 Ventilated Pit C2 Human R2 Appplication S5 Alternating Powered R11 Incineration Dodoma (Tanzania) is shown in the Figure. The technolo- U2 Urine Double Dry Diverting Pit gies listed in the Compendium range from a simple dry Urine Dry Toilet C1 Jerrycan R1 Urine Fertilizer toilet to a complex biogas reactor. The sole criteria for Urine S9 Storage Tank C3 Motorized inclusion of options were the promotion of health and sus- Beigewater tainability. Thus, options such as hanging toilets (erected Greywater Infiltration/ over surface waters) or bucket latrines were not included, Treatment Disposal Greywater given the potential for disease transmission. R8 Soak Pit Stormwater Drainage Community decision-making The task of changing deeply ingrained ideas among From 6 types of toilet (U), 11 options for collection and storage (S), 6 for conveyance (C) and engineers and policymakers is not an easy one. For this 12 for use/disposal (R), these components were deemed feasible in the Chang’ombe district of Dodoma. The Compendium describes the suitability of each module (rectangles), listing reason, the Compendium is first used in target groups ­advantages and disadvantages and giving details of maintenance requirements and the costs where the participants can ask questions freely. When of construction and operation. Special attention is paid to impacts on health and questions of the groups subsequently come together to discuss pos- acceptance. In the present case, grey water management had to be designed in such a way sible options, all the stakeholders are already familiar that anal cleansing water (beige water) could also be processed, since the use of toilet paper with the same concepts and terminology. After the is unacceptable for many Muslims. This system does not include a “treatment” stage; other systems incorporate, for example, a constructed wetland between transport and use/disposal focus group workshops, the professionals design various (see p. 12). systems, which are then presented to the community. In this first phase, it is essential that trained professionals are involved, so that time and money are not wasted on technically inappropriate options. Ultimately, however, the system and its components are chosen by the com- Infrastructure projects based on the HCES approach munity. If the community is unwilling or unable to select may take more time to implement and involve greater a complete system initially – for example, because some planning and coordination efforts than capital-intensive of the technologies may still seem foreign to the major- projects planned in a “top-down” fashion. However, the ity of people concerned – pilot projects may be a useful investment in this type of project development is justi- first step. fied because the HCES approach offers the one result that previous approaches have been unable to achieve – Different solutions for Tanzania and Costa Rica sustainability. i i i In Dodoma, the capital of Tanzania, the HCES launching workshop was held in October 2007. Seventy participants from various backgrounds (e.g. primary school teachers, clerics, unemployed) formed working groups to discuss topics such as social and economic aspects, hygiene and sanitation infrastructure. Among the ideas now being pursued are improvements to sanitation through the use of urine‑diverting latrines with twin pits used alternately. Another option under consideration for this dry region is the “Arborloo” – a portable latrine that is moved from one shallow pit to the next when the first is full. The old pit is then closed and planted with a tree. In San Martin (Costa Rica), by contrast, where more water is available, small- The Eawag pilot projects testing the HCES approach and the ­development of the Compendium are supported by the Swiss scale sewerage systems can be implemented. These Agency for Development and Cooperation (SDC), the National networks connect up to 200 households, with pipes Centre of Competence in Research North-South (NCCR North- laid just below ground level. Instead of using expensive South) and the Swiss State Secretariat for Economic Affairs (seco). manholes, seal chambers are installed at each connec- Household-Centred Environmental Sanitation: Provisional Guide- tion point to facilitate maintenance, to avoid blockage of line for Decision Makers (English/French/Spanish), Eawag, the low-gradient pipes and at the same time to prevent 2005. overflowing at peak times. A community sewer of this Compendium of Sanitation Systems and Technologies, Eawag, type discharges into a settling pond or a simple treatment 2008 (available from August 2008). International Year of Sanitation 2008: http://esa.un.org/iys/ plant. and www.siedlungshygiene2008.ch Millennium Development Goals: www.un.org/millenniumgoals/ HCES approach: www.eawag.ch/hces 42 Urban water management

Faecal sludge: health risk or natural resource? In vegetated drying beds, faecal sludge can be dewatered and mineralized by bacterial degradation of organic matter. This permits hygienic recycling of nutrients and recovery of humified sludge. However, these facilities need to be adapted to local conditions and operated with indigenous plants. Ives M. Kengne, Doulaye Koné

More than 1.1 billion urban inhabitants of developing countries – about 40 % of the urban global population with access to sanitation facilities – use onsite installations such as latrines, septic tanks, or aquaprivies for urine, faeces and wastewater storage/dis- posal at household level. These facili- ties are not connected to sewers and are designed to be regularly emptied manually or mechanically when full. Most often, faecal sludge collected Vertical flow constructed wetland pilot bed for faecal sludge dewatering and mineralization in sub-Saharan countries. from onsite sanitation installations is spread untreated on farmland, disposed of with household waste, cost methods for the separation of use as a humus-forming material on streets, or simply discharged into solid and liquid fractions. This step (organic fraction 40 %) and fertilizer

rivers and lakes. is essential in order to avoid hygienic (N: 2%, P2O5: 2.3%). However, after problems and to permit the recovery the facility had been in operation for Separating liquids and solids of resources or energy. 6 months, the biosolids still contained A key requirement for sustainable In cooperation with the Asian Insti- high concentrations of parasites, par- management of faecal sludge is the tute of Technology (AIT, Bangkok), ticularly helminth eggs (79 eggs per development of efficient and low- Eawag has previously demonstrat- gram of total solids). For this reason, ed, especially in Thailand, that con- the dewatered sludge needs to be co - structed wetlands represent a viable composted – e. g. with organic solid Ventilation pipe solution for the treatment of faecal waste – or stored for a longer period sludge. However, the characteristics before it can be spread on farmland. of sludge vary widely from one re- No significant differences were ob- gion to another, and appropriate in- served when different sludge loading digenous plants need to be identified rates (100 – 300 kg of total solids per so as to ensure successful operation m2 per year) were used. of these facilities. The results obtained in this project Drainage will be reviewed in a scale-up cur- pipe Antelope grass and papyrus rently under way in Dakar (Senegal) Percolate tank In studies carried out in Cameroon, (see the article opposite). i i i antelope grass (Echinochloa pyrami­ Structure of a vegetated drying bed with sand and gravel filter layers. dalis) and papyrus sedge (Cyperus In this example, the sludge water (percolate) is drained into a tank. papyrus) were shown to be suitable Kegne I.M. (2008): Design optimization of dryings beds vegetated with Echi- plants. In the case of antelope grass, nochloa pyramidalis (Lam.) Hitch & Wetland flowers and vanishing sludge which is used as a forage plant world- Chase and Cyperus papyrus L. for Two examples involving vegetated drying beds illustrate just how wide, biomass production tripled, faecal sludge treatment in Sub-Saha- quickly an effective system can find acceptance among the local compared with growth in natural ran countries. PhD thesis, University population. On Koh Phi Phi (Thailand), a constructed wetland was habitats, to 100 –150 tonnes of dry of Yaounde, Cameroon. planted with ornamentals as well as reeds and cattail. The flowers Kone D., Cofie O., Zurbrugg C., Gallizzi matter per hectare per year. We are are now sold at a profit to local hotels by the operators of the K., Moser D., Drescher S., Strauss ­facility. And in Dakar (Senegal), under cover of darkness, farmers now investigating whether the qual- M. (2007): Helminth eggs inactiva- have already helped themselves on several occasions to treated ity of the grass would allow it to be tion efficiency by faecal sludge de- sludge that was being stored, rather than waiting for parasite test- sold as animal fodder. watering and co-composting in tropi- ing to be completed. The product’s advantages as a humus-form- The biosolids accumulating on the cal climates. Water Research 41 (19), ing material and fertilizer are obviously appreciated. 4397–4402. top of the beds are well suited for Urban water management 43

Developing local expertise

In Senegal, Eawag is supporting the development of an education and research centre for sustainable faecal sludge management. While the focus is on building local capacity, Eawag research is also benefiting from the opportunity to scale up approaches and treatment ­methods at the new facility. Doulaye Koné, Mbaye Mbéguéré

In the Dakar region, an estimated such as that developed by a former 170 000 m3 of faecal sludge from Eawag PhD student in Burkina Faso, latrines and septic tanks arises per or, together with the authorities, to year – sludge that has to be treated develop business models designed and then appropriately disposed of to make sludge management attrac- to prevent public health risks in a city tive for small businesses. with a population of over 2 million. These joint efforts, including the With financial support from the work carried out at the education and World Bank and the European Union, research centre, have already pro- Senegal’s National Sanitation Agency duced encouraging results: (ONAS) has already built two treat- E The expertise of ONAS staff in FSM ment plants in Dakar and is planning has been strengthened. Experience to extend the faecal sludge manage- from other countries (e. g. Benin and Sludge is delivered to one of the two ONAS facilities. ment (FSM) programme to other Mali) indicates that treatment facili- cities. Since 2005, at the request ties often encounter difficulties with- of the Senegalese government, this in the first year of operation. The two the economic viability of private programme has been supported by ONAS facilities have already been emptiers, the management of public Eawag. In July 2007, a new education operating smoothly for 18 months. infrastructure and the definition of and research centre was inaugurated This has not escaped the notice of responsibilities. in Dakar. the emptiers: the two plants are E National experts are playing a each receiving 50 truck loads a day, greater role: before the collabora- Implementing large-scale rather than the 10 deliveries originally tion with Eawag, ONAS – like many processes planned, which means that they are other authorities in the region – re- At the pilot facility, ONAS and Eawag already operating close to capacity. lied on experts from abroad for FSM can scale up treatment processes Training modules are enhancing dia- projects. Support of this kind is developed in the laboratory and in logue between the private sector and costly and of limited duration, and it smaller pilot studies – for example, other stakeholders. is often not possible to respond to faecal sludge humification in con- E In Dakar, FSM is no longer seen new problems as they arise. Now structed wetlands (see the article op- merely as a technical problem. A the country has experts of its own. posite). However, this collaboration comprehensive strategy has been de - In Touba, Senegal’s second-largest also provides an opportunity to test veloped to facilitate improvements. city, a contract to build a new FSM sustainable FSM planning concepts, This covers, for example, rules for plant was recently awarded to a local engineering company – which had hired staff previously involved in our project. E In partnership with the University of Dakar (UCAD), we are currently developing a training programme on water for doctoral students and an MSc course in sanitary engineer- ing for developing countries, which is due to start in the autumn of 2008. i i i

The Eawag/ONAS pilot facility in Dakar is supported by the Velux Foundation.

www.sandec.ch > Main Topics > Excreta The Dakar research facility was officially opened by Senegal’s Deputy Minister of Infrastructure, and Wastewater Management Urban Hydraulics and Sanitation in July 2007. 44 Urban water management

Rapid detection of pathogens

A new screening method based on flow cytometry allows pathogens to be detected in drinking water and other types of samples within two hours. With existing detection methods, it is ­necessary to wait two days for visible colonies of microorganisms to develop on culture media. The new technique has great potential. Hans-Anton Keserue, Hans Peter Fuechslin, Stefan Kötzsch, Thomas Egli

For centuries, water was consid- time and only permit the detection of per litre. For comparison, the limit ered to be of good quality if it was culturable cells. specified by the Federal Office of clear, with a pleasant taste and no Public Health for Legionella pneu­ bad odours. Since the mid-nine- Drawbacks of recent methods mophila in drinking water is 1000 col- teenth century, bac- Efforts have been made to develop ony-forming units per litre. The method’s teria have been culti- faster detection methods. The most The resting stages of protozoan par- strength is vated on solid media frequently used approach is the asites, such as Giardia and Crypt­ (agar plates). Bacteri- polymerase chain reaction (PCR), osporidium, can also be enumerated apparent when ologists showed that in which multiple copies of a DNA – with a detection limit of approx. pathogens have to bacteria can cause dis- sequence are synthesized. However, 40 cysts per litre. Although this is not be isolated from eases, including many the PCR method can be compro- yet sufficiently sensitive for tap wa- which are waterborne. mised by the presence of inhibitory ter, it is adequate for more complex complex matrices to Today, despite major compounds, and it is not capable of matrices such as wastewater, milk permit detection. advances in microbi- differentiating between living and or stool samples, where pathogen ology, the official de- dead cells. Other methods in use concentrations are far higher. Our tection method for the majority of involve the labelling of microbes and method could therefore be of inter- pathogenic micro­organisms still in- viruses with dyes and enumeration est not only for the analysis of drink- volves cultivation on agar plates and via fluorescence microscopy. But ing water but also in the food indus- enumeration of the colonies formed. even with increasing instrument try, in clinical microbiology and for However, such assays take a long automation and digital image analy- rapid assessment of microbiological sis, this method of quantification is risks in disaster areas – wherever the still time-consuming and laborious. target cells have to be isolated from complex matrices before they can be Alternative approach reliably detected. i i i Sample At Eawag, we have developed flow cytometric (FCM) techniques which Labelling with can be used for screening drinking fluorescent dye (via DNA, water – e. g. for determining the antibody-coated total bacterial count or the bacterial surfaces, etc.) regrowth potential in the distribu- tion network. Our new method for rapid detection of pathogens begins with an enrichment step, in which Cells cells present in a water sample are collected by filtration and resus- pended in phosphate buffered saline (PBS). They are then labelled using antibody‑coated microscopic mag- netic beads and isolated from other cells (immunomagnetic separation) Signal Hammes F., Berney M., Wang Y., Vital 520 nm Laser so that they can subsequently be M., Köster O., Egli T. (2008): Flow- 488 nm directly identified and enumerated by ­cytometric total bacterial cell counts flow cytometry. as a descriptive microbiological pa- rameter for drinking water treatment Preventing epidemics processes. Water Res. 42,269–77. Hammes F. A., Egli, T. (2005): New Initial results indicate that the method method for assimilable organic car- allows detection of bacterial patho- bon determination using flow-cyto- gens such as legionella or Escheri­ metric enumeration and a natural Rapid detection of microbial pathogens ­ ­microbial consortium as inoculum. using immunomagnetic separation followed chia coli O157 within two hours, with Environ. Sci. Technol. 39, 3289–3294. by flow cytometric analysis. a detection limit of around 500 cells Urban water management 45

Helping the helpers – a handbook for relief missions After natural disasters or in a crisis situation, survival may depend on an intact water supply system and hygienic disposal of excreta, wastewater and waste. In cooperation with a team of experts, Eawag has developed a manual for emergency assignments involving Switzerland’s humanitarian aid workers. Christian Zurbrügg 1

Natural disasters and humanitarian gency relief efforts. To facilitate this crises arising from armed conflicts task, Eawag – as part of a team of are all too common – the devastating experts – was requested by the SHA Indian Ocean tsunami, hurricanes in (see Box) to develop an instrument

Central America, an earthquake in in the form of a handbook, including Valsangiacomo Claudio northern Pakistan, conflicts in west- checklists and decision tools. Lists ern Sudan or Lebanon. The health of of questions are designed to support the victims of such crises is severely preparations and analysis of the situ- threatened by inadequate supplies of ation: for example, what other organ- drinking water and poor wastewater izations have already been deployed and waste disposal. Contaminated and for what purpose? Are water and water and insanitary conditions cause soap for personal hygiene available at diarrhoea and infections – diseases sanitary facilities? In addition, proce- that may ultimately claim more lives dures are suggested for systematic than the original event. priority-setting. Decisions have to be Should this damaged drinking water well in Aceh (Indonesia) be re- paired? The well is continuously contaminated by a pit latrine situated taken in close consultation with the behind the black plastic sheet. Hygiene often overlooked people concerned, local authorities After the tsunami, Switzerland’s Hu- and relief agencies. Who is to take manitarian Aid responded with relief what action where and when, and measures, providing shelter and care who is to coordinate the efforts? Preparatory measures Briefing  obtaining the basics Material for the homeless and injured. A team procurement equipment of specialists in the areas of medi- Guidance and documentation cine, logistics and water assessed lo- The Handbook should help to en- Transfer in the country cal needs on the ground and initiated sure that all key areas are taken into of assignment emergency assistance. In retrospect, consideration. It can also serve as Information procurement/Material this aid can be described as efficient. a notebook for aid workers in the  procurement during a stopover in In certain cases, however, an em- field, documenting their experience the country of assignment phasis on the restoration of drinking and assuring knowledge transfer to water supplies meant that too little other experts on subsequent assign- attention was paid to questions of ments. i i i sanitation and, in particular, waste-   water disposal. Supporting the team on Rapid Assessment Hygiene, Experts deployed within a matter of assignment Water and Sanitation days or even hours are subject to high expectations. Firstly, they need Problem Analysis Need  to ensure drinking water supplies and Humanitarian Aid Unit Assessment Potentials for SDC / HA Assistance wastewater/solid waste disposal for The Swiss Humanitarian Aid Unit (SHA) is the operational arm of the govern- the assignment team. At the same ment’s international Humanitarian Aid  Pre-Design of Immediate time, they need to assess the situa- programme. The SHA is a “militia corps”, Measures tion in the disaster area as rapidly as with a pool of about 700 people ready possible and decide where and how for deployment at short notice. Civil Switzerland can contribute to emer- engineers, hydrogeologists and chemists Overview of the procedure for a relief mission, with the relevant from the Water and Sanitation group checklists (1– 6) from the handbook. construct or repair facilities for water treatment, storage and distribution, and 1 Co-authors of the handbook are Peter are responsible for excreta and waste- Kaufmann, Aquawet; Karl Wehrle, Skat; Ueli water management and for training local Graf, Construction, Transport and Energy personnel. Employment with the SHA is Directorate of Canton Bern; Chris Zurbrügg, assignment- and project-based. Sandec/Eawag. 46 Urban water management

Nutrient overload in the Tha Chin River According to a material flow analysis carried out by Eawag, the main source of nutrient pollution in Thailand’s Tha Chin River basin is not pig farming, but fish farming. In the light of this finding and other results from the study, possible mitigation measures can now be discussed by all stakeholders. Monika Schaffner, Ruth Scheidegger, Hans Peter Bader, Irene Wittmer

In developing and emerging coun- be identified. An Eawag case study are well above the regional recom- tries, river water quality improvement on nutrient pollution in the Tha Chin mendations. Nutrient pollution from is of vital importance for both people River basin in Thailand aimed at trac- aquaculture is due to overfeeding and ecosystems. Conventional water ing and quantifying the sources and and the discharge of pond sediments quality models study pollution on the flows of phosphorus and nitrogen in into canals. basis of inputs to receiving waters, the river system. With these insights from the MFA but they give no indication of how The Tha Chin River, a branch of the model, it is now possible to discuss and where these inputs arise. Chao Phraya River, flows through with all stakeholders how pollution the intensively used Central Plains could be most effectively reduced Analysis leading to remedial of Thailand. This flat region is char- through locally adapted measures. measures acterized by a heavily regulated net- Such measures could include ap- A material flow analysis (MFA) repre- work of waterways, with low flow propriate fertilizer application in rice sents a valuable complement to wa- rates and changing flow directions. In production, feeding practices better ter quality models, making it possible 2000, a basin-wide fish death raised suited to the specific requirements to analyse where pollutants originate awareness of the water quality issue of fish, a more balanced feed nutrient and how they spread within a river among policymakers and the public. content, or the reuse of sediments system. Options for avoiding or pre- Studies showed that high nutrient from fish farms. However, such venting pollution at source can thus loads (eutrophication) and the result- recycling would only make sense if ing oxygen depletion are of particular the sediments are not contaminated concern. with antibiotics or other chemical ad- ditives used in aquaculture. i i i Aquaculture Aquaculture: main source of Rice paddies nutrients Pig farming The aim of our study was to identify

Poultry farming the main sources of nutrient inputs Tha Chin to the river system and to explore Agriculture possible remediation measures. A Industry simple MFA model was developed Households on the basis of field observations, This project was carried out under the combined with existing data, expert ­National Centre of Competence in Re- Nitrogen surveys and estimates. The results search (NCCR) North-South programme, indicate that: co-funded by the Swiss National Science E More than 50 % of all nutrients Foundation and the Swiss Agency for ­derive from aquaculture. ­Development and Cooperation. E Intensive rice production in the Wittmer I.: Modeling the Water and ­region accounts for more than 15 % ­Nutrient Flows of Freshwater Aqua- of the nutrient inputs. culture in Thailand. A Material Flow Analysis, in Department of Environ- E Pig farming is among the major mental Science. 2005, ETH Zürich: contributors mainly in the middle Zürich. Phosphorus Bangkok reaches of the basin. Schaffner M., Wittmer I. (2006): Alarm E Nutrient inputs from industry and – zu viele Nährstoffe im Tha Chin; households, as well as from poultry Eawag News 62d. Schaffner M. (2007): Applying a Material farming and agriculture, are orders Flow Analysis Model to Assess River of lower magnitude. Water Pollution and Mitigation Poten- The study reveals not only the main tials – A Case-Study in the Thachin Golf of Thailand contributions, but also the underly- River Basin, Central Thailand. Disser- tation Universität Bern. NCCR North- Main sources of nitrogen and phosphorus pollution in the Tha Chin ing causes. In the rice paddies for South / Eawag. River basin. example, fertilizer application rates Urban water management 47

When tap water smells musty

Whenever tap water smells peculiar, water utilities receive calls from worried consumers. At Eawag, methods have been developed for identifying – and if necessary eliminating – odour compounds in drinking water. Advanced oxidation with ozone and hydrogen per- oxide has proved to be a successful approach. Holger Lutze, Andreas Peter, Urs von Gunten

Taste and odour problems are the occur seasonally. Here, ozonation is a when untreated water containing most frequent causes of complaints promising option, as the breakdown bromide undergoes ozonation. We to drinking water suppliers. Although of trace compounds is supported by investigated to what extent odour the substances that cause these not one, but two reactive substances compounds can be eliminated using problems do not pose a health risk, (ozone and hydroxyl radicals), and ozone-based processes many consumers are concerned the process can be relatively eas- while at the same time With some when their tap water has an unpleas- ily controlled. Thus, the formation of keeping bromate forma- substances, ant smell. Apart from residues of hydroxyl radicals can be promoted tion to a minimum. In our we can smell chlorine (which is added to water by the addition of hydrogen peroxide study, conventional ozona- supplies as a disinfectant), odour (H2O2), and this advanced oxidation tion was compared with a single drop compounds from natural sources process can enhance the removal of advanced oxidation. The in a swimming give rise to most complaints. Micro- ozone-resistant compounds. experiments were per- pool. organisms in surface waters (espe- formed both at laboratory cially algae) or on biofilms in water Avoiding unwanted scale and in a pilot plant. This plant distribution networks can produce a by‑products was operated in cooperation with the wide variety of odour compounds. As well as optimizing the elimination Zurich water utility as part of the of contaminants, however, it is nec- cross-cutting Wave21 project.

Advanced oxidation essary to preserve the disinfectant Advanced oxidation with O3/H2O2 Since most odour compounds origi- capacity of ozone and to prevent the was shown to be a valuable tool for nate in surface waters, many odour formation of undesirable by-products controlling odour episodes associat- problems can be dealt with by appro- as far as possible. The compound ed with lake water. Not only does this priate water treatment. This calls for of most concern in this connection process eliminate odour compounds a method that can respond flexibly is bromate, a potentially carcino- significantly more effectively than to peak concentrations, which often genic oxidation product, which arises conventional ozonation, but the for- mation of bromate is also minimized. Pilot-scale research has shown that existing ozone treatment facilities can be upgraded, if necessary, so

ETH-Rat, A. Pol as to remove odour compounds and other contaminants. i i i

A nose (and an instrument) for odours Before taste and odour compounds can be dealt with, they first have to be de- tected and identified. For this purpose, a method previously applied mainly in the perfume industry was further developed at Eawag. It involves a combination of technology and the human nose: while a water sample is analysed in a mass spectrometer, odours are simultaneously “sniffed out”. Any irregularities detected by the researcher’s sensitive nose are recorded. By analysing the peaks in the mass spectra, it is then possible to iden- tify the substance responsible for a given Collecting samples from the ozone reactor in the Wave21 pilot plant at the Lengg lake water odour component. treatment facility operated by Zurich’s water utility. 48 Urban water management

Energy self-sufficiency for wastewater treatment plants? Today, despite the production of biogas, conventional wastewater treatment plants (WWTPs) are net consumers of energy. At Eawag, a process for the removal of ammonium nitrogen which includes anaerobic oxidation has been further developed. Because less energy for aeration is required, the addition of a carbon source is not needed and biogas production can be increased, this anammox process could bring WWTPs a step closer to energy self‑sufficiency. David Salzgeber, Jack Eugster, Karin Rottermann, Adriano Joss, Hansruedi Siegrist

Ammonium-rich sludge digester liq- More sludge for biogas uid can undergo nitrogen removal in production a separate treatment step at WWTPs. A further advantage of the PNAA This can prevent the nitrogen load process is that it allows better use from being unnecessarily increased to be made of anaerobic energy re- when sludge liquid is recirculated covery. If nitrogen is removed from to the primary settling tank. In the the digester liquid before it is recir- conventional process involving nitri- culated to the primary settling tank, fication and denitrification, a carbon the nitrogen load is reduced at this source (e. g. methanol) has to be stage. Accordingly, less substrate is added to reduce nitrate to molecular required for denitrification in the bio- nitrogen. In addition, this process re- logical treatment step. The hydraulic quires a lot of energy for aeration. retention time in primary settlement To avoid these drawbacks, we have can be extended. Thus, more sub- now further developed a method in- strate is available for digestion, and volving anaerobic ammonium oxida- The 400-litre SBR reactor at the Eawag the production of biogas is increased. ­testing facility. tion: in PNAA (Partial Nitritation and Combined with the savings in aera- Anaerobic Ammonium oxidation), tion energy, the PNAA process can part of the ammonium is oxidized regularly delivered from the Zurich- bring WWTPs a step closer to energy with oxygen to nitrite, while the re- Werdhölzli WWTP. Although anam- self-sufficiency in their operations. In mainder is oxidized anaerobically to mox bacteria grow slowly and we order to promote understanding of molecular nitrogen using the nitrite used a small amount of inoculum for PNAA and to improve control of the produced in the process (Figure). this experiment, we achieved excel- process, we are currently elaborating The addition of a carbon source is lent N removal performance after a dynamic model of the performance thus no longer needed, and the aera- only 4 months, with a hydraulic reten- observed in the reactors. i i i tion energy required is reduced by up tion time of 1 day. to 60 %. Given the good results obtained with the 400-litre reactor and the From laboratory to full-scale savings to be expected from lower operation energy and methanol consumption, The intermittently fed sequencing we were able to find two plants – Salzgeber D., Joss A., Siegrist H. (2007): batch reactor (SBR) has a capacity Zurich-Werd­hölzli and St. Gallen-Au Autotrophe Schlammwasserent­ of 400 litres. The sludge liquid was – that were prepared to implement stickung (Nitritation/Anammox) in the process at full scale. Both reac- einem SBR. Gas Wasser Abwasser 3, tors – with a volume of 300 m3 at the 205–209. Siegrist H., Salzgeber D., Eugster J., St. Gallen and 1400 m3 at the Zurich Nitrification Partial Joss A. (2007): Anammox brings NH NH plant – began to operate in the late WWTP closer to energy autarky 4 nitritation 4 0.86 O2 [43%] summer/autumn of 2007, inoculated due to increased biogas production 2 O [100%] 2 with sludge specially produced in an and reduced aeration energy for th 3 ­N‑removal. 11 World Congress on NO2 NH4 NO2 8 m reactor at the Eawag testing ­Anaerobic Digestion, 2007, Brisbane. Carbon source facility. While the initial results of full- [e.g. methanol: Wett B. (2007): Development and imple- 3.4 kg/kgN] scale operation are encouraging, they mentation of a robust deammonifi­ 0.5 N2 0.5 N2 also show that smooth running of the cation process. 4th IWA Leading Edge Denitrification Anaerobic ammonium oxidation process depends on well-equipped Conference and Exhibition on Water and Wastewater Technologies, Conventional nitrification/denitrification (left) and partial nitritation with facilities and continuous supervision, 3– 6 June 2007, Singapore. anaerobic ammonium oxidation (PNAA). especially during the start-up phase. Urban water management 49

Catching polluted road runoff in a filter bag

When rain falls on roads after a lengthy dry period, the runoff is black, contaminated with, for example, heavy metals from tyre and brake pad abrasion. Filter bags installed in drains can prevent these substances from entering receiving waters – but not all fleeces are equally suitable for this purpose. Markus Boller, Martin Wyttenbach

Filter fleeces can be used for the of which parameters are crucial for treatment of road runoff. As shown evaluating fleeces with regard to re- by earlier Eawag studies, they retain tention capacity, pressure losses and a substantial proportion of the pollut- run times. In a pilot plant specially set ant content since heavy metals (cad- up for these tests, road sludge was

mium, lead, zinc, copper) and poly­ diluted to specified solids concentra- Jürg Kaeser, Schoellkopf AG cyclic aromatic hydrocarbons (PAH) tions with water from the rainwater are bound to dust emissions from harvesting facility at Eawag’s new road vehicles. “Forum Chriesbach” building. This In cooperation with the University of “standardized” road runoff was then Applied Sciences Burgdorf and the used to test various textile filters for Canton Bern Water Protection Of- pressure loss and solids/heavy metal fice, Eawag tested both fleece filter retention with different filter veloci- bags and rotating filter drums with ties and loads. automatic backwash. Filter bags tend The tests showed that there are con- to be more suitable as a decentral- siderable differences between the ized measure for treatment of less fleeces (see Figure). For example, contaminated runoff in roadside fleece 3 has unfavourable properties, drains, while filter drums are suit- with poor retention performance and able as centralized processing units a rapid increase in pressure loss. for more heavily contaminated road runoff, e.g. from sewered sections of Sediment in filter bags Changing a textile filter bag filled with road sludge. motorways. The filter performance determined in the tests cannot be directly ap- Pilot plant plied to real-life conditions. It has tom, making the filter impermeable. Scale-up and operational aspects been shown that fleeces used as Depending on the amount of rain- of the installation and cleaning of filter bags in drains also function as fall, filtration proceeds via larger or textile filters were studied by the sedimentation containers, exhibiting smaller areas of the sidewalls. This experts responsible in Canton Bern. a solids retention capacity of up to allows filters to be used for substan- The treatment performance and 20,000 mg TSS/m2 – many times tially longer periods before cleaning, colmation (clogging) of various filter higher than was found in the filter considerably increasing the poten- fleeces were investigated by Eawag. experiments. In bags of this type, tial for application of fleece filters in The results provide an indication road sludge is deposited at the bot- practice. i i i

100 120 fleece 1 80 100 fleece 2 fleece 3 80 60 60 40 40 Broad-based cooperation fleece 1 A variety of research projects investigat- 20 fleece 2 Solids eliminatio [%] 20 ing pollutant loads in roof and road run- fleece 3 vf = 1.6 m/h Pressure loss [cm WS] vf = 1.6 m/h 0 0 off are combined under the heading of 0 100 200 300 400 500 0 100 200 300 400 500 “Rain analysis”(www.regenanalyse.ch). Filter load [g TSS/m2] Filter load [g TSS/m2] In addition to Eawag, the following part- ners are involved: the Federal Offices for Performance of fleece filters as a function of total suspended solids (TSS) load (grams per Roads and the Environment, the Federal square metre). Elimination of solids is initially poor in new fleeces, but subsequently improves Institute of Technology Lausanne, Canton rapidly. As the filter load increases, performance declines again somewhat (left). Increasing Bern, the University of Applied Sciences pressure loss (right) means that the filter gradually becomes clogged and is able to treat less Burgdorf and the Association of Swiss and less wastewater. Filter velocity in both experiments: 1.6 m/hour. Solids content of waste- Road and Traffic Engineers. water: 70 mg TSS/l. 50 Urban water management

Forward-looking strategic planning for the sanitation sector In designing sanitation infrastructure, planners are confronted with a variety of uncertainties associated with the long operational life of the facilities. Few approaches are available for ­handling these uncertainties. But if tomorrow’s sewerage systems and wastewater treatment plants are misconceived, costly adaptations will be required. Eawag has therefore developed a forward-looking planning approach that makes it possible to assess the sustainability of technical and organizational options. Eckhard Störmer, Annette Ruef, Damian Dominguez, Max Maurer, Bernhard Truffer

As Switzerland’s sanitation infrastruc- Foresight (RIF) – that allows uncer- dealt with. Also subject to change ture largely dates from the 1960s and tainties to be taken into account more is the sanitation sector’s conception 1970s, local authorities and municipal systematically. This methodology of itself as a public service provider, associations are increasingly facing was tested and refined in three case given the pressures of liberalization decisions on major investments in studies – in the Klettgau region (Can- and privatization. Lastly, the regional the renovation of wastewater treat- ton Schaffhausen), in the Kiesen/ consequences of climate change ment plants and sewers. Planning Aare Valley (Canton Bern) and in – with heavy rainfall events and generally focuses on remedying ex- the Dübendorf/Wangen-Brüttisellen/ droughts – are difficult to assess. isting shortcomings. However, few Dietlikon region (Canton Zurich). Overall, it is apparent that in order people are aware of the implications to meet future challenges, it is not of 30- to 50-year planning horizons. Taking uncertainties into enough merely to extrapolate from Decisions made today will affect the account past experience. next 1–2 generations. Uncertainties for the sanitation sector The future of sanitation in a given are driven by economic development Sanitation sector planning: region depends on developments in and population growth in the catch- a demanding exercise numerous areas and thus involves ment area. These factors determine In view of the diversity of tasks substantial uncertainties. For this not only wastewater volumes and the performed by the sanitation sector, reason, a research group at Eawag quantities of problematic substanc- careful planning is a highly complex sought to develop a planning meth- es, but also the capacity to pay for process. As well as controlling water odology – Regional Infrastructure infrastructure. Additional unknowns pollution, there is a need to ensure include the future development of acceptable charges for society and environmental and water protection business, allocation of costs accord- requirements, which are shaped by ing to the polluter-pays principle, po- Klettgau case study regulations, but also by the demands litical controllability and much else In the wine-growing region of Klettgau (Canton Schaffhausen), of the public and businesses at local besides. The importance of these on the border with Germany, the wastewater treatment plant has level. A current example is the ques- tasks will be rated differently by the reached the end of its lifespan after over 30 years. The members of the Sanitation Association’s Construction and Operation Com- tion of how micropollutants are to be various stakeholder groups, depend- mittee were not convinced by proposals for rebuilding or renewal of the plant. They were not sure whether continuation of the existing system represents an appropriate solution for the next 30 years. By taking part in the RIF pilot project, they aimed to ­identify future challenges for the sanitation sector and to assess a wide range of alternative solutions in a strategic planning process. Comprehensive consideration of the sanitation tasks of the Sanitation Association and the local and cantonal authorities allowed the potential for further optimization – beyond WWTP operations – to be investigated. As a future strategy, regional stakeholders participating in the RIF process recommended options that had previously been scarcely discussed: firstly, the establishment of a multi-utility service provider that could largely relieve local ­authorities of their sanitation-related responsibilities and subsequently take on additional functions, e.g. provision of drinking water. Alternatively, the possibility of collaboration with a neighbouring WWTP in Germany is to be explored. Prior to the process, the latter option had been regarded as not politically feasible. The open, unfettered discussion and transparent analysis of the pros and cons of various proposed solutions led the partici- pants in the RIF process to make clear recommendations on the future orientation of the sanitation ­sector. The RIF planning approach promotes long-term strategies rather than quick fixes. Urban water management 51

ing on the future context. All these Cross-border Multi-utility aspects have to be taken into consid- association eration in a forward-looking assess- ment of strategic options. WWTP Option 2 The RIF approach Infra-facility Klettgau The Regional Infrastructure Foresight WWTP planning approach involves the fol- Option 1 lowing four elements:  Wastewater is diverted to neighbouring association WWTP in Klettgau is expanded, and additional tasks are E Development of scenarios for the  Klettgau Sanitation Association (SA) operates taken on: region and the sanitation sector con- municipal sewers in Klettgau (and possibly other local  Power generation (Kompogas anaerobic digestion) authority tasks)  Operation of municipal sewers text in 25 years’ time. This allows  Possibly drinking water, waste, etc. systematic identification of uncer- WWTP light Local mini-WWTPs tainties in the development of con- Licensed mini-WWTP text conditions. operator E Elaboration of options for the sanitation sector in the region. The solutions considered comprise tech- WWTP Hallau light WWTP Hallau nical and organizational elements Licensed mini-WWTP (see Figure): is the catchment area operator to be enlarged or reduced in size? Are the organization’s responsibili-  Renovation of WWTP without sludge treatment  Decentralized mini-WWTPs, first for heavy polluters,  Industry required to treat wastewater internally then for all households ties to be expanded or cut back?  Transfer of responsibilities, focus on core compe-  Goal: decommissioning of WWTP Are contemporary approaches or in- tences  Klettgau SA to be disbanded, mini-WWTPs to be operated by licensed maintenance firms novative emerging technologies to be preferred? Should wastewater Options considered in the Klettgau case study. Two options are being pursued – a cross-border association and a treatment be centralized or decen- multi-utility. tralized? E In-depth analysis of the target di- mensions of sustainable sanitation in tions and interests can also be taken Sustainable solutions the region. This creates transparency into consideration in the assessment The sanitation sector is having to with regard to the particular chal- of options. meet growing demands with dimin- lenges in the individual scenarios. ishing resources. Regional Infra- E Finally, evaluation of options. Based Result: strategic action plan structure Foresight enables decision on the future demands placed on The result of the RIF process is a makers to take a global view of the the sanitation sector by citizens and strategic recommendation for the sector – from household connection businesses, the various options can long-term orientation of wastewater to receiving waters – and to iden- be ranked for each context scenario. management in the region, combined tify synergies with local authorities The assessments are then compared with an action plan for the next steps and other wastewater management and those options are selected which in the planning process. agencies in the region. With RIF, have been shown to exhibit a high In the case studies, a variety of con- strategic options for sustainable level of desirability and a low conflict clusions were reached. In the Klett- sanitation can be comprehensively potential. gau region (see Box), the process assessed. i i i resulted in the recommendation of Exploiting regional two options that had previously ap- knowledge peared unacceptable or had barely The RIF project was sponsored by the Swiss National Science In conventional planning procedures, been discussed. In the Kiesen/Aare Foundation (SNSF) as part of the National Research Programme far-reaching strategic definition of the Valley, possibilities for increasing NRP 54 “Sustainable Development of the Built Environment” future development of the sanitation cooperation were explored, and (www.nfp54.ch). Eawag’s partners in the project are the ETH ­Zurich, Bern University, Empa and the Fraunhofer Institute for sector is often delegated to planning/ the merger of several associations ­Systems and Innovation Research/ISI (Germany). engineering consultants. In contrast, was formulated as a vision for the the RIF process is based on the idea medium term. In the economically Störmer E., Ruef A., Truffer B. (2007): Regional Infrastructure Foresight. EFMN Brief No. 116. www.efmn.eu that local decision makers should be dynamic region of Dübendorf/Wan- Störmer E. (2007): Nachhaltige Strategieplanung für die kommu­ involved in shaping the fundamental gen-Brüttisellen/Dietlikon, it was nale Abwasserentsorgung. Umweltperspektiven Oktober strategy. At two workshops, these proposed that a multi-utility should 2007. parties are brought together with rep- be established, offering additional Dominguez D., Worch H., Markard J., Truffer B., Gujer W. (2008): resentatives of regional stakeholder wastewater-related services to local Closing the Capability Gap: Strategic Planning for the infra- structure sector. California Management Review (submitted). groups so that their future expecta- authorities.

Highlights 2007 53 Eawag 2007review of Under its new Director, Eawag had an exceptionally busy year in 2007. Thanks to Janet Hering’s membership of the ETH Board (as a representative of the four research insti- tutes Empa, WSL, PSI and Eawag) and her international contacts, new partnerships were initiated and existing ones strengthened. In 2007, 117 groups visited Eawag, while two members of the Federal Council – Pascal Couchepin and Moritz Leuenberger – also demonstrated their interest in water research and the new building Forum Chriesbach. Below, we look back over some of the highlights of the year. Andri Bryner

recycling at the Hohtaelli (Zermatt) cableway station (3286 m a.s.l.) won Accolades for Eawag the Muelheim Water Award. Environ- In 2007, once again, several Eawag mental toxicologist Roman Ashauer find ways of dealing with – future projects and a number of researchers was the winner of the generously challenges in this area. The stud- received awards or distinctions. For funded Innovative Science Award, ies carried out to date have shown reasons of space, only a few exam- presented by the European Chemical that the existing sectoral orientation ples can be mentioned: Directorate Industry Council (cefic), for his work makes it difficult to meet emerging member Willi Gujer was granted an on improving the definition of water water management challenges and honorary doctorate by the Technical quality criteria. i i i deploy resources in an economically University of Denmark, while Urs von optimal manner. There is a lack of Gunten (Water Resources and Drink- Overall water management overall strategies and mechanisms ing Water Department) was made an strategy for cross-sectoral coordination. In Honorary Professor at the Harbin In- To permit an integrated approach to 2008, Water Agenda 21 will develop stitute of Technology (China). Roland the management of water resources, into a network of Swiss water profes- Schertenleib (Directorate), together key stakeholders from the Swiss sionals. The deficiencies identified with Markus Eggenberger of the water and wastewater sectors, in- are to be addressed, and stakehold- Swiss Agency for Development and cluding Eawag, have launched the ers are to be supported in develop- Cooperation, received the Campaign “Water Agenda 21” project. The aim ing sustainable water management Medal for works in the water sector of this initiative is to analyse – and solutions, with Eawag making a vital in Vietnam. The project involving the contribution to this process. i i i installation of a compact, closed sys- tem treatment plant for wastewater Potential of urine source separation Urine source separation is a promis- What’s the right way to look through a microscope to observe life ing wastewater management option, forms in water? Aquatic research for the younger generation at the especially for rapidly expanding cities Eawag-Empa summer camp. Bottom: Dialogue – the key to respect. Director Janet Hering in conversation with Eawag staff. 54 Highlights 2007

for the detection of ecotoxic effects, or new analytical methods. E Information platform: publishing The ABCs of water new findings in specialist journals and At a number of events – including other media, organizing continuous the 20th anniversary of the Depart- education events for professionals ment of Environmental Sciences at and students, and answering queries the ETH Zurich, a summer camp for as a public service contact point. children of Eawag staff, a “Research Public funding totalling CHF 2 million Night” and the Basel trade fair – per year will be available for the peri- Eawag researchers presented water- od 2008 –2011. i i i related topics to the general public. The centrepieces of the special ex- Partying hard The search continues for new methods of separate urine treatment, hibition on water at the muba fair In an internal survey, Eawag staff ideally for use in decentralized systems. were the “Sound of Rivers” project reported above-average levels of (page 29) and information on global satisfaction with their jobs and work- in coastal areas. This was the mes- water consumption in the food sec- ing environment. One of the reasons, sage taken home by the 250 peo- tor. Recordings of the Basel rivers no doubt, is the strength of the ple – researchers, officials, industry Birs, Wiese and Rhine were used bonds existing within departments representatives and policymakers to explain to visitors the connection and throughout the institute. These – who attended Eawag’s Info Day on between the sound spectrum and in turn are promoted by the annual 7 March 2007. The event was widely diversity, and a huge bratwurst illus- “works outing” and the now-tradi- covered on television and radio and trated the immense amounts of wa- tional celebrations. The biggest date in the press, reflecting the high level ter that are required to produce meat in the 2007 social calendar was the of public interest in this topic, both – around 15,000 litres for a kilogram nationally and internationally. The of beef. i i i completion of the cross-cutting No- vaquatis project does not mark the Ecotoxicology Centre taking end of Eawag’s research in the area shape of separate urine collection and treat- In the autumn of 2007, Parliament fol- ment. New methods are currently lowed the Federal Council in approv- being sought to allow the nutrients ing the establishment of a Centre Members of the Directorate in “The Wizard nitrogen and phosphorus to be re- for Applied Ecotoxicology at Eawag. of Schweiz”. moved and recovered from urine at This Centre is to be developed in the earliest possible stage, using cooperation with the Federal Insti- Forum Chriesbach Christmas party, decentralized technologies. The op- tute of Technology Lausanne (EPFL) attended by almost 400 people. The portunities and potential applications in 2008, filling the gap created by theme chosen by the organizers for of such decentralized systems are the closure (in 2001) of the Institute this highly successful evening was also being explored in a wide-ranging for Toxicology in Schwerzenbach. ups and downs (“Stägeli uf, Stägeli analysis. A business plan has already been ab”). Among the most memorable www.novaquatis.eawag.ch drawn up, and facilities for the Centre contributions was a specially devised are currently being prepared in the musical performed by the Directo- Eawag office building at Dübendorf rate. i i i where renovation work was complet- ed at the end of 2007. The Centre’s Upgrade successfully essential functions are: completed E Clearing house: monitoring devel- In 2007, the 1970-vintage office opments in applied ecotoxicology block at the Dübendorf site was and discussing current and emerg- completely refurbished and extend- ing issues and potential solutions ed by two storeys. Eawag will no with representatives of practice and longer need to rent additional office academia. space, but these savings are not the E R&D: developing, for example, only advantage: thanks to various cost- and time-saving test methods improvements, energy consumption is now significantly lower despite the increase in floor space, and the Eawag’s stand at the special exhibition on water at the muba fair in proportion of self-generated power Basel. is to be further increased by the in- Highlights 2007 55

as “a kick-off meeting to intensify re- search collaborations between Swit- zerland and the European Union”. E with the Swiss Gas and Water river engineering sectors for the In- ­Industry Association (SVGW), partic- ternational Water Management Fo- ularly in the water supply sector; rum. This event, sponsored by the re- E with the Electron Microscopy insurer Swiss Re, is not a conference Center of the ETH Zurich (EMEZ), in the conventional sense. Instead, it ­focusing on biological research meth- The completely refurbished Eawag office brings together decision-makers in a ods; building at Dübendorf – now two storeys workshop setting to share their expe- E with the California Institute of higher – will also house the new Ecotoxic- ity Centre. rience – in this case on the topic of Technology (Caltech), for a Summer river restoration. With its long tradi- Undergraduate Research Fellowship tion of river engineering and a well- (SURF) programme. stallation of a photovoltaic system. established water protection regime, i i i In addition, the allocation of space Switzerland serves as a model for between Forum Chriesbach and the other countries in the management 10-point plan for fish laboratory and office buildings has of rivers and streams. However, At the end of August, the interdis- been optimized. All workstations many restoration projects do not get ciplinary “Fischnetz+” project is- are now located close together. In beyond the planning stage, and even sued a 10-point plan designed to re- Forum Chriesbach, operations are those which are implemented are store fish stocks and improve fish currently being streamlined, and a not always as successful as hoped. habitats. In Swiss rivers, yields have detailed energy accounting project is Accordingly, one of the conclusions declined dramatically – e. g. brown being carried out with support from of the IWMF 2007 was that greater trout catches have decreased by two the Swiss Federal Office of Energy. attention needs to be paid to de- thirds since 1980. The measures pro- Plans for 2009 include the moderni- cision-making processes, the defini- posed are based on the results of the zation of the laboratory building and tion of goals and the evaluation of “Fischnetz” project (1998–2003), the rehabilitation of the Chriesbach outcomes. i i i in which Eawag, the Federal Office river, which flows through the Eawag for the Environment and all the can- site. At the Kastanienbaum site, the Expanding partnerships tons sought to identify the causes boathouse, which dates back to 1938 In 2007, Eawag’s collaboration with of declining fish yields. The plan ­ and is now a listed building, was the Federal Institute of Technology includes measures to make hydro- gently renovated: this involved, for Lausanne (EPFL) was further inten- power operations more fish-friend- example, improving the insulation, sified. Apart from the development ly, control fish diseases and reduce extending the photovoltaic system, of the Ecotoxicity Centre and joint chemical pollution through alterations and installing a new kitchen and research efforts in the field of eco- to wastewater treatment plants. It workstations for doctoral students. toxicology, this involved in particular also indicates how fish habitats can Also restored was the large mural on the participation of Eawag research- be improved through rehabilitation the facade, which depicts the “leg- ers in teaching at the EPFL and the efforts. www.fischnetz.ch end of Kastanienbaum”. i i i establishment of joint professor- ships. Eawag also strengthened part- Water professionals learning nerships with other institutions, for from each other example: In September 2007, Eawag con- E with the European Commission’s vened 45 leading experts from the Joint Research Centre (JRC), espe- research, administration, NGO and cially the Institute for Environment and Sustainability at Ispra (Italy). On 16 March 2007, a JRC Informa- eier tion Day was held at Eawag. Charles

Ueli M Kleiber, State Secretary for Education and Research, described the event

IWMF participants on a restored section of Among the measures recommended in the 10-point plan is the fish- the River Thur. friendly design of hydropower facilities, including fish ladders at dams. 56 Personnel News

tance to developing and carrying out research projects in collaboration with local partners, thereby promot- ing local expertise and research head of the Chemistry Department Personnel skills. He contributed his knowledge for a time, but after the re­organization and networked approach to a wide in 2000 she moved to the Limnology New appointment variety of international bodies. As Department. Here, she established Gabriele Mayer: At the beginning Chair of the Environmental Sanitation a new group to investigate the ef- of September, Gabriele Mayer was Working Group of the Water Supply fects of sunlight on the availability appointed head of HR & Finances at and Sanitation Collaborative Council of organic carbon, iron and copper Eawag. She gained her first degree (WSSCC), he played a decisive role in in rivers, lakes and oceans. In col- in business administration, majoring the formulation of the Bellagio Prin- laboration with doctoral students, in tourism. She then took a Master’s ciples for Sustainable Sanitation. He postdocs, and research associates, in European Tourism Management at also initiated the household-centred Barbara Sulzberger produced a large Bournemouth University – a course environmental sanitation (HCES) ap- number of outstanding publications which included semesters in Breda proach (page 39), a new model for and was regularly invited to partici- (Netherlands) and Madrid. Gabriele the planning and implementation of pate at international conferences and Mayer worked at Kuoni, serving as sanitation measures in urban areas of on expert committees. From 2002, head of Finances & Administration developing and transition countries. she also served as Editor-in-Chief Switzerland and a member of the In the Directorate of Eawag, Roland of the journal Aquatic Sciences. Executive Committee. She subse- Schertenleib was responsible for She remains a member of the UN quently managed the newly estab- property, among other matters. His Environmental Effects Assessment lished company TRX Central Europe, main challenges in this capacity were Panel. developing a market in the travel the completion of the pioneering sector for automated online booking Forum Chriesbach building and the Rudolf Müller: Anyone wishing to systems. She joined Eawag from planning and realization of the reno- enquire about practical aspects of Xerox AG, where she was CFO Swit- vated office facility in Dübendorf. fisheries management – associa- zerland. Eawag will still be able to benefit tions, fishermen or authorities – was from his expertise in various activi- well advised to contact the biologist Retirements ties, such as the National Centre of Ruedi Müller. He always understood Roland Schertenleib: Water has Competence in Research (NCCR) the concerns of practitioners, in- been the theme of Roland Scherten- North-South, or a project concerned cluding the Romands, thanks to his leib’s career ever since he obtained with decentralized sanitation options proficiency in French. His career at his Master’s in Civil Engineering – Capacity Building in Environmental Eawag began with his PhD thesis from the ETH Zurich. After working Science & Technology in Northern on body temperature in freshwater as a consultant for municipal waste- Vietnam (ESTNV). fish, which he completed in 1974. A water treatment plants and sewer year later, after working as a research networks, and taking a Masters in Barbara Sulzberger: At Bern Uni- associate in Toronto, he became a Sanitary Engineering at Stanford versity, where she received her doc- researcher at Eawag. From 1986 to University, he joined the Engineering torate in 1983, and then as a postdoc 1999, he was head of the Depart- Department at Eawag in 1976. From at the renowned Royal Institution ment of Fisheries Sciences (until the 1980 to 2003, he was head of, first, of Great Britain in London, Barbara reorganization in 2000). From 1986 to the Dübendorf based WHO Interna- Sulzberger was already interested in 1989, he served as the first president tional Reference Center for Waste physical chemistry – in particular, the of the newly founded Swiss Society Disposal and then the Department of photochemical conversion of solar of Limnology (SGL), and from 2000 Water and Sanitation in Developing energy. Until 1986, she worked as a to 2006, he was Chairperson of the Countries (Sandec). From 2000, he research chemist at Ciba-Geigy. She European Inland Fisheries Advisory was a member of the Directorate. then established an environmental Commission (EIFAC) of the FAO. Early on, Roland Schertenleib recog- photochemistry research group at Ruedi Müller was an active member nized that Eawag’s responsibilities Eawag. Using modern methods, she of numerous bodies, ranging from the should include helping to tackle the studied photochemical processes on federal cormorant-fish working group growing problems of the Third World mineral surfaces in aquatic systems, (AG K+F) to the expert committee on through practice oriented research. the formation of reactive oxygen spe- He always attached great impor- cies and their role in transforming natural and synthetic compounds. She qualified as a lecturer at Bern University in 1998 and taught mainly at the ETH Zurich. At Eawag, she was Personnel News 57

changes in the ecosystem of Lake Brienz. After the Sandoz warehouse fire at Schweizerhalle, he played a Death key role in analysing the effects of Heinz Ambühl: On 14 May 2007, the release of toxic chemicals into the Heinz Ambühl died in his 79th year. Rhine. In his research, Ruedi Müller As a hydrobiologist, he set new focused on how individual fish spe- standards, starting with his thesis on cies are affected by lake eutrophica- concerned with the optimization of “The importance of flow velocity as tion, and on how management can be gravel filters for drinking water prepa- an ecological factor”, for which he adapted to respond to such changes. ration and wastewater treatment. His was awarded the Silver Medal of the More recently, he concentrated on manuals are still consulted today. He ETH in 1959. In 1960, having pre- questions of population genetics then became fascinated with the idea viously worked as a water chemist and developmental biology, e.g. how proposed by a Lebanese professor, in Canton Aargau, he was appointed genetic diversity in fish is altered by Aftim Acra, that it should be possible head of the Hydrobiology/Limnology breeding and stocking measures. to use sunlight to disinfect drinking Department at Eawag and took on Internationally, he has been a leading water. Although the notion was not numerous teaching responsibilities. light in whitefish research. taken seriously by some scientific In 1972, he was elected Extraordi- colleagues, he refined the method narius of Hydrobiology. Many of the Urs Uehlinger: As an expert in and, together with Silvio Canonica research areas which he promoted stream ecology, Urs Uehlinger has and Klaus Mechsner, demonstrated – e. g. fish biology, fish management, earned an international reputation. In that it was indeed effective and could ecotoxicology and multidisciplinary 1977, having completed his thesis represent an opportunity for coun- studies involving mathematical mod- on cyanobacteria at the Federal Insti- tries with inadequate drinking water elling – have since become estab- tute of Technology (ETH) Zurich, he supplies. Thanks to his commitment lished as independent departments joined Eawag to work on biological and persistence, the Sodis (Solar at Eawag. Long before the advent of and physical processes in lakes. In Water Disinfection) project has been computer based literature searches, the 1980s, the focus of his research supported by a variety of donors and he compiled for Eawag a catalogue shifted to rivers and streams, where has now gained international rec- of almost 20,000 original publica- he was particularly interested in ognition among experts. As Martin tions on register cards, with an index nutrient and organic matter dynam- Wegelin was always open even to comprising hundreds of keywords. ics. In 1986, as a visiting scientist unconventional ideas, he managed to In a voluntary capacity, he edited the at Idaho State University, he was establish the PET bottle as a univer- Schweizerische Zeitschrift für Hy- impressed by the untouched wild sal container for Sodis. This system drologie and developed it into the rivers. Accordingly, when Professor is now used in more than 28 coun- renowned journal Aquatic Sciences. James Ward became head of the tries, with the support of the WHO Whenever he started a new scien- Limnology Department in 1995, Urs and in many cases also government tific project, a careful approach and Uehlinger began to concentrate on agencies. “Mister Sodis” was never an appropriate sampling technique alpine streams. Following extensive discouraged by setbacks: his visits were top priorities for him. If no ana- studies in Val Roseg (Upper Enga- to Coca-Cola Headquarters in Atlanta lytical methods or procedures were dine), Ward and Uehlinger jointly have become legendary at Eawag, available, he would devise an ingen- edited a book entitled “Ecology of a even though they failed to secure ious method of his own. More than Glacial Flood Plain”. Urs Uehlinger the incorporation of instructions for thirty PhD students and numerous supervised numerous PhD students Sodis on the labels of all Coca-Cola undergraduates benefited from his and undergraduates and lectured on PET bottles. Martin Wegelin will con- selfless support. His long-term stud- stream ecology at the ETH Zurich. tinue to serve Eawag as a senior ad- ies of ecosystems laid the founda- After leaving the Department of viser and contact for Latin American tions and remain a limnological gold Aquatic Ecology, he intends to pursue programmes at the Sodis Reference mine for many contemporary models his research on lotic ecosystems. Center. and new projects. With the death of Heinz Ambühl, the limnology com- Martin Wegelin: ETH-trained civil munity has lost an internationally engineer Martin Wegelin took a Mas- recognized champion of Swiss water ter’s degree at the IHE in Delft and protection. i i i taught at the University of Dar es Sa- laam (Tanzania) before joining Eawag in 1982. His initial research was 58 bibliothek / aqa

Books – and total immersion

Eawag-Empa Library. Standing at they will have to be replaced. “But researchers who – in spite of increas- the counter in the new library, the that’s the exception,” says librarian ing digitization – may still want to water researcher is apologetic: dur- Jutta Studer. “The vast majority of read an article in the small hours ing his field work, the books he had our clients are exemplary,” library of the morning or at the weekend. borrowed had got “a bit wet”, he head Bas den Brok agrees, “and if Since the summer of 2006, the Empa confesses. Strictly speaking, they something does happen to a book, and Eawag libraries at the Dübendorf had fallen overboard. At any rate, they hang their heads in shame and site have been combined in the new get out their wallets.” Of course, it is Forum Chriesbach building. Accord- the exceptions that make library life ingly, 2007 saw a sharp rise in the interesting, and sometimes there are number of items borrowed – from pleasant surprises, too – for instance, around 3200 to 4900 (+ 53 %). In when books are returned that had fact, the increase in the number of never officially been borrowed. But registered users – from 1290 to 1590 Brok is sympathetic in cases like this: – was so large that the operators of “If a researcher is so engrossed in the NEBIS library network enquired his work that he forgets to check out whether everything was in order. a book when he leaves the library, Bas den Brok is pleased: “It shows then it’s not premeditated.” He has we’re on the right track.” But num- less sympathy for the individual who bers are not everything: if all the regularly walks off with a specific books from the various departments journal: “That’s unfair to everyone were to be held centrally, as originally else. We’re not a kiosk!” Brok is planned, the library would soon run determined not to close the library into problems of space. And librar- Bas den Brok, Head of the Eawag-Empa Library, talking to librarian outside working hours: the open- ians are always reluctant to throw out Stephanie Hofmann. door principle meets the needs of books. i i i

An elegant sufficiency

Staff canteen aQa. The weekly menu the catering company DSR – aQa is around 1000 unwashed glasses and for the staff canteen aQa is one of frequented not only by Eawag and piles of other dishes in the kitchen.” the most popular links on the Eawag Empa staff, but also by employees Overall, however, chief cook Czer­ Intranet. When it became temporar- of nearby companies. The kitchen winski is very satisfied: “Ninety-nine ily inaccessible for Empa staff follow- and dining facilities were originally per cent of the feedback from our ing a system migration, complaints designed for 150 guests. This means customers is excellent.” There were were received immediately. Each that the catering team led by Pe- some complaints when an external day, between 220 and 280 meals are ter Czerwinski sometimes needs to bakery stopped supplying dark fruit prepared at the kitchen operated by draw on all its improvisation skills and rolls – Czerwinski now bakes these stamina – for example, if 50 extra vis- himself. i i i itors need to be fed at short notice, or on the occasion when a box con- taining 20 kg of frozen peas ripped, 40 kilos of salad a day spilling its contents over the kitchen The rush starts at 11:30. Each day, aQa offers three set menus and a salad bar. floor. The 5-strong aQa team (with One of the set meals is vegetarian and a total of 4.1 full-time positions) was one – ­possibly the same dish – carries also hard pressed at the 2007 Christ- the organic “Goût Mieux” label. Czer­ mas party: more than 360 guests winski is no longer surprised by the fact queued up at the catering stands in that environmentally aware Eawag staff don’t necessarily choose the organic the atrium of the Forum Chriesbach ­option: “You eat whatever you fancy.” building. But, as Peter Czerwin- His team prepares almost 40 kg of salad ski recalls, the event itself went off per day. Every month, he purchases smoothly: “The shock came the next 200 kg of potatoes, 80 kg of coffee beans and 750 litres of milk. Peter Czerwinski, aQa’s chief cook: “Even environmental scientists day, when I had to plough through www.dsr.ch, www.goutmieux.ch don’t always choose the organic option.” kinderpavillon / umwelt-team 59

A home from home

Childcare centre. Eveline Vonlan- “but it must be sore – so I couldn’t then, the manager of the joint Eawag- just run off.” Happily, the boisterous Empa childcare facility, arrives a little band of children at the “KiPa” have later than planned: a four-year-old so far been spared any more dramatic has taken a tumble and bumped his accidents. In 2007, one broken finger head. “Nothing serious,” she says, was the only serious case requiring the attentions of voluntary in-house first-aiders. The children clearly feel Childcare centre comfortable at the centre. Particular- At the childcare centre, a total of 33 pre- ly popular are the activities in which schoolers aged between 4 months and all three groups participate, as these 5 years are looked after in three groups from 07:30 to 17.30. The centre is run events make new interactions possi- by the “IG Kinderpavillon” association. ble or bring together siblings who, as Empa and Eawag make the new building a matter of policy, are not assigned At the Eawag-Empa childcare centre, it is often the fathers who drop opened in August 2006 available to the to the same group. The shared ac- IG and also take on administrative re- off or pick up their children tivities include singing, weekly forest sponsibilities. In the allocation of places, priority is given to children of Eawag and days and, of course, the various par- Empa staff; their parents pay reduced ties which parents are also invited to and crannies of the old building. So rates. Two places are supported by the attend. does the team have everything it neighbouring company Givaudan for its There is plenty of space for the chil- could wish for? Eveline Vonlanthen employees. The children are looked after dren to let off steam, not only in the replies: “A few male carers would be by 9 qualified carers, 4 trainees and 3 interns. The members of the IG serve on woods or in the new garden around good for the children.” But the pros- a voluntary basis. The centre is currently the centre, but in the building itself. pects of that are still fairly dim. “Oh fully subscribed, with waiting times Having got used to the wide play yes,” she adds, “and we’ve wanted of 6–12 months for new enrolments. corridor, none of the carers would a teepee for the garden for quite a www.kinderpavillon.eawag-empa.ch now like to go back to the nooks while.” i i i

Green mobility

Eco-Team. In December 2006, used by Eawag to subsidize pass- this year’s “bike to work” initiative, Eawag set itself new energy goals, es for staff using public transport. the Eawag teams – actively support- paying greater attention to transport. Compared with bonuses for non car ed by members of the Directorate – In 2007, we began the process of users, this type of support offers the once again improved on the previous ­implementation: advantages of saving administrative year’s results. i i i E Eawag is taking all necessary costs and being tied to a specific pur- Thomas Lichtensteiger, with the Eco-Team measures to ensure that its electric- pose. As a result, many staff also use www.umwelt.eawag.ch ity and heating requirements are pro- public transport for personal travel. gressively – and by 2010 fully – met In 2007, Ecodrive courses for Eawag by renewables and in a sustainable staff who are still dependent on cars manner. demonstrated how fuel consumption E All travel undertaken by Eawag can be reduced by appropriate driv- staff is to be carbon-neutral.. ing techniques.

CO2 reductions and transport Cycling: as attractive as ever. The measures. The Kastanienbaum site pool of 50 Eawag bikes available for recently celebrated the 10,000th kil- loan is heavily used. At Dübendorf, it owatt-hour of self-generated solar was agreed with officials that bicycle power. The new photovoltaic sys- stands will remain in place at Stett­ tem – twice as large as its pred- bach station until the construction ecessor and with an annual capac- of the Glattalbahn railway line starts; ity of 10 MWh – came on stream in arrangements for the subsequent pe- the autumn of 2007. It was financed riod are being worked out. The plans The photovoltaic system on the renovated boathouse in Kastanien- by CO2 charges levied internally on for a cycle path free of intersections baum has already generated more than 10,000 kWh of power. It was air travel. These charges are also and traffic lights are completed. In financed by internal CO2 levies on air travel. 60 ORGANization chart / advisory board

Organization

Directorate Janet Hering (Director) Rik Eggen (Deputy Director) Willi Gujer Peter Reichert Roland Schertenleib (until July 2007) Bernhard Wehrl CCES Staff of the Directorate Competence Centre Environment + Further education, knowledge Sustainability of the ETH Domain transfer, communication Peter Häni

Research departments Support Surface Waters Water Resources + Drinking Water IT Services Alfred Wüest Rolf Kipfer Gabriel Piepke

HR + Finances Aquatic Ecology Environmental Engineering Gabriele Mayer Jukka Jokela Hansruedi Siegrist

Vocational Training Research topic: Max Reutlinger Aquatic ecosystems Fish Ecology + Evolution Urban Water Management Ole Seehausen Markus Boller Research topic: Technical Services

Urban water management Max Mauz Water + Sanitation in Environmental Chemistry Developing Countries (Sandec) Gender Activities Juliane Hollender Chris Zurbrügg Gabriella Meier

Environmental Microbiology Systems Analysis, Integrated Eawag / Empa Thomas Egli Assessment + Modelling Peter Reichert Library Bas den Brok Research topic: Environmental Toxicology Comprehensive Innovation Research Marc Suter (until 31.12.2007) in Utility Sectors (Cirus) Nursery Chemicals and their impacts Kristin Schirmer (from 1.1.2008) Bernhard Truffer Joerg Klausen

Advisory Board

André Bachmann Ursula Brunner Erika Forster Günter Fritz Peter Arbenz Jürg Meyer Bruno Oberle (President) Lawyer, Ettler State Councillor, Head of Environment, President Helvetas Director Waste- Director, Federal Executive Director, Brunner Suter St. Gallen Health and Safety, water Treatment Office for the BMG Engineering Bächtold, Zurich Ciba Specialty Association Lucerne Environment (FOEN), Inc, Schlieren Chemicals, Basel region Bern Departments 61

Directorate

Janet Hering Rik Eggen Willi Gujer Peter Reichert Roland Schertenleib Bernhard Wehrli (Director) (Deputy Director) (until July 2007)

Staff of the Directorate

Peter Häni Herbert Güttinger Isabel Wiedmer Sandra Ziegler Handschin Leader Further education Knowledge transfer Communication

Research departments

Alfred Wüest Jukka Jokela Ole Seehausen Juliane Hollender Thomas Egli Marc Suter Kristin Schirmer (until 31.12.2007) (from 1.1.2008)

Rolf Kipfer Hansruedi Siegrist Markus Boller Chris Zurbrügg Peter Reichert Bernhard Truffer

Support

Gabriel Piepke Gabriele Mayer Max Reutlinger Max Mauz Gabriella Meier Bas den Brok Joerg Klausen 62 Figures 2007

Finances

Financial statement (in CHF) 2005 2006 2007 Personnel 33 136 459 35 203 743 37 868 533 Materials 2 310 907 2 911 752 3 260 866 Other general expenses 5 051 942 5 556 131 6 781 444 Infrastructural expenses 3 399 665 5 160 395 6 710 435 Depreciation 1 029 614 871 718 1 082 462 Provisions 19 660 190 10 088 456 296 041 Expenditure 64 588 777 59 792 195 55 999 781 Federal government funding 46 624 468 49 795 822 1 38 491 577 Third-party resources 10 293 942 13 481 019 11 564 156 Miscellaneous revenue 1 110 280 1 010 742 1 655 624 Income 58 028 690 64 287 583 51 711 357 Result – 6 560 087 4 495 388 –4 288 424

1 Not including funding for building

Investments (in CHF) 20 929 645 9 370 632 14 714 393 Real estate 18 463 636 6 883 301 12 780 799 Movables 2 259 269 2 439 510 1 663 563 IT 206 740 47 821 270 031

Breakdown of expenditure 2007 Development 2001–2007

Provisions Personnel Depreciation expenditure 60

Infrastructural expenses 50

Other general expenses 40

Materials expenses 30

Third-party resources 2007 CHF million 20 Other funding CHF 0.83 million Research funding European research CHF 3.5 million programmes 10 CHF 0.6 million

Business-oriented 0 research 2001 2002 2003 2004 2005 2006 2007 CHF 2.64 million Federal research contracts Third-party funds CHF 3.98 million Federal funding Total expenditure figures 2007 63

People

Personnel People Whereof Whereof Full-time women non-Swiss ­equivalents Full professors 1 5 1 3 5 Titular professors 13 2 5 13 Scientific staff (academic staff) 152 50 81 134 PhD students 76 37 40 71 Technical staff 78 37 8 64 Administrative staff 63 55 8 43 Apprentices 24 13 1 24 Trainees 1, 2 12 6 7 12 Affiliated staff (nursery) 1 16 16 1 14 Total 439 217 15 380

1 Not or not directly employed by Eawag. 2 Only traineeships funded by Eawag at 31.12.2007, total for 2007: 63.

Age structure Women Men Total Women Men

15–19 11 11 22 50%

20–29 48 36 84 57%

30–39 56 76 132 42%

40–49 44 38 82 54%

50–59 27 39 66 41%

60–65 9 12 21 43%

Total 195 212 407 80 60 40 20 0 20 40 60 80 Number

Percentage employment Women Men Total Origin Women Men Total 1–49 % 22 9 31 Switzerland 133 130 263 50–79 % 47 11 58 EU 48 66 114 80–99 % 35 14 49 Other 14 16 30 100 % 91 178 269 64 Figures 2007

Activities

2005 2006 2007 Supervised dissertations 105 107 108 Supervised diploma theses 97 104 108 Publications in refereed journals 186 194 202 Publications in non-refereed journals 47 49 55 Spin-offs – 1 – Patents, licence agreements – – 1 Service contracts 39 38 28 Prizes 8 24 19 Teaching programmes at ETHZ, EPFL 85 93 75 Teaching programmes at other universities 31 37 39 Teaching programmes at universities of applied sciences 10 10 4 PEAK courses (further education) 9 6 5 Conferences 39 45 54 Committee memberships 180 201 216

Further details and annual reports in pdf format are available at: www.eawag.ch/annualreport. This Annual Report presents only a small selection of Eawag’s research, teaching and consulting activities. It is also available in German. All publications by Eawag staff can be viewed online or ordered by e-mail. http://library.eawag-empa.ch [email protected]

The e-mail addresses of all staff are available via the search function on the website: www.eawag.ch

Publication details Editing and unsigned texts: Andri Bryner All unattributed photos: Eawag Graphics: Yvonne Lehnhard, Peter Nadler Design: TBS Identity, Zurich Layout: SLS Peter Nadler, Fällanden Printing: Mattenbach AG, Winterthur Translation: Jeff Acheson, Bottmingen Copyright: Eawag, May 2008. Reproduction is permissible with citation of the source: “Eawag – aquatic research; Annual Report 2007”. Specimen copies should be sent to: Eawag, Communication, P.O. Box 611, 8600 Dübendorf, Switzerland

Eawag, Überlandstrasse 133, P.O. Box 611, 8600 Düben- dorf, Switzerland Tel. +41 (0)44 823 55 11, Fax +41 (0)44 823 50 28

Eawag, Seestrasse 79, 6047 Kastanienbaum, Switzerland Tel. +41 (0)41 349 21 11, Fax +41 (0)41 349 21 68 Eawag Überlandstrasse 133 8600 Dübendorf Switzerland Tel. +41 (0)44 823 55 11 Fax +41 (0)44 823 50 28 www.eawag.ch [email protected]