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Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, 3 - 7 October 2004, Accra Ghana 1 Ecological sanitation - innovative.

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Presentation on theme: "Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, 3 - 7 October 2004, Accra Ghana 1 Ecological sanitation - innovative."— Presentation transcript:

1 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 1 Ecological sanitation - innovative wastewater management systems Christine Werner, Patrick Bracken, Florian Klingel Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH ecological sanitation programme, Division 44 – environment and infrastructure Commissioned by: Water Resources Protection Workshop, 2-6 May, 2005, Selam Hotel, Asmara

2 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 2 Freshwater - increasingly scarcity and degrading quality 1,1 billion people no access to safe drinking water 2,6 billion people inadequate/no sanitation Expected growth of the global population by 2 billion people in next 25 years, mostly in urban areas in developing and emerging market economies, and many of them doomed to poverty if no concerted effort is made to resolve the water crisis 90 % of wastewater either poorly treated or not treated at discharge (only 25% of WWTPs built in DCs functioning) 80 % of all diseases and 25 % of all deaths in developing countries can be attributed to polluted water (WHO) In Sub-Saharan Africa at least 1/3 of incomes spent to treat water-borne diseases, 90% of all malaria deaths, more than 200 Million bilharzia infections, diarrhoeal diseases 240 times hi- income (Hansen, 2004) The international context world water and sanitation crises

3 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 3 Achievement of poverty eradication and sustainable development by rapidly increasing access to basic requirements such as clean water, sanitation, energy, health care, food security and the protection of biodiversity Set target for water and sanitation: To halve by 2015 the proportion of people without access to safe drinking water and those without adequate sanitation millennium development goals (MDGs) To reach this the sanitary provision rates of the 90s will have to be quadrupled (UN WWDR 2003)

4 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 4 Why is sanitation important? It provides a healthy environment = healthy people (able to secure improved livelihoods and break the cycle of poverty and ill-health) For children - no diarrhoeal disease or other health hazards results in increased school attendance etc. Can reduce number of children below 5 who die as a result of unsafe water, sanitation and hygiene. Can particularly help improve womens lives and increased security can protect against sexual harassment and violence for women and girls. Preventive environmental health measures are as important and at time more cost-effective than health treatments Basically - it saves lives!!!

5 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 5 Some Principles of Sanitation It is about behaviour and hygiene, not (just) about building toilets It is a household decision with public implications Central and local govt have roles, but behaviour is, in the end, decided at the household level Children matter!! 90% of health benefits are among pre-school kids… and worm infections among school-age children Supply and demand are critical

6 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 6 Why do people want sanitation ? Top 5 reasons - from the Philippines 1. No smell and flies 2. Cleaner surroundings 3. Privacy 4. Less embarrassment when friends visit 5. Less disease In Benin 1. Prestige and status 2. Comfort convenience and privacy 3. Protection against accidents in the bush 4. Increase the rent Rarely is disease prevention mentioned!!

7 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 7 shortcomings of conventional watercarriage sanitation Unsatisfactory purification or uncontrolled discharge of more than 90 % of wastewater worldwide Severe water pollution, unbearable health risks Consumption of precious water for transport of waste High investment, energy, operating and maintenance costs Frequent subsidization of prosperous areas and neglect of poorer settlements Loss of valuable nutrients and trace elements contained in excrements due to discharge into waters Problems with contaminated sewage sludge in combined, central systems Linear end-of-pipe technology Introduction to ecosan

8 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 8 Retention of solids Infiltration of liquids Polluted groundwater Nitrates Viruses Pathogens shortcomings of conventional drop and store sanitation Introduction to ecosan

9 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 9 excreta are a valuable resource million tons per year (as N + P 2 O 5 + K 2 O) Represents nutrients with a market value of around 15 Billion US dollars. Introduction to ecosan

10 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 10 recovery of energy content (covering about 20% of cooking energy needs for a typical family in a developing country) energy savings in fertilizer production & wastewater treatment excreta are a valuable resource

11 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 11 business as usual will not allow us to provide sanitation to those who need it most. Conventional systems have failed - costs, resource efficiency, safeguarding public health and sustainability, we cannot continue to waste our non-renewable resources the global water, hygiene and soil degradation crisis requires new approaches Innovative, holistic and sustainable approaches needed to provide safe and decent sanitation, reduce poverty, contribute to food security, preserve our environment and maintain the natural basis of life need for a new approach to sanitation Introduction

12 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 12 Alternative approach: ecological sanitation – ecosan What does it mean? Introduction to ecosan

13 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 13 advantages of ecological sanitation Improvement of health by minimizing the introduction of pathogens from human excrements into the water cycle Promotion of safe, hygienic recovery and use of nutrients, organics, trace elements, water and energy Preservation of soil fertility, Improvement of agricultural productivity Conservation of resources Preference for modular, decentralised partial-flow systems for more appropriate, cost-efficient solutions Promotion of a holistic, interdisciplinary approach Material flow cycle instead of disposal introduction

14 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 14 eco-sanitation concepts and strategies eco-sanitation… … is not just one technology, but an approach based on an eco-system-oriented view of material flows to deal with what is presently regarded as waste and wastewater for disposal … applies the basic natural principal of closing the loop by using modern and safe sanitation and reuse technologies … opens up a wider range of sanitation options than those currently considered.

15 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 15 Principles of ecosan systems NUTRIENTS closing the loop between sanitation and agriculture FOOD Pathogen destruction

16 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 16 Principles and objectives of ecological sanitation The main objectives of eco-sanitation are to: provide affordable, hygienically safe, and desirable sanitary facilities; reduce the health risks related to sanitation, contaminated water and waste; prevent the pollution of surface and groundwater; prevent the degradation of soil fertility; optimise the management of nutrients and water resources.

17 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 17 Climate protection Flood protection Resource conservation Business and labour promotion Food security Health Sustainable agriculture + Conservation of soil fertility Integrated Water Resources Management ecosan is a cross-sectoral approach

18 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 18 Organics kg COD/ (Person·year) Volume Liter / (Person·year) – l 500 l 50 l source: Otterpohl Nutrient content kg N,P,K / (Person·year) N P K composition of household wastewater Introduction to ecosan greywaterurine faeces

19 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 19 of no major hygienic concern volumetrically the largest portion of wastewater contains almost no nutrients (simplified treatment) may contain spent washing powders etc. 3. greywater less hygienically critical contains the largest proportion of nutrients available to plants may contain hormones or medical residues 2. urine hygienically critical consists of organics, nutrients and trace elements improves soil quality and increase its water retention capacity 1. faeces characteristicfraction characteristics of substances Introduction to ecosan

20 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 20 source: Drangert, 1998 fertilizer potential of human excreta Introduction to ecosan

21 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 21 composting, anaerobic digestion organic waste soil improvement, biogas treatment utilisation substances faeces (brownwater) anaerobic digestion, drying, composting biogas, soil improvement constructed wetlands, gardening, wastewater ponds, biol. treatment, membrane- technology greywater (shower, washing, etc.) irrigation, groundwater- recharge or direct reuse urine (yellowwater) liquid or dry fertiliser hygienisation by storage or drying filtration, biological treatment rainwater water supply, groundwater- recharge separation of substances

22 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 22 Introduction to ecosan eco-sanitation concepts and strategies To optimise cost efficient, high quality treatment and recycling options, two principles are very often being applied in ecosan systems: flow streams with different characteristics, such as faeces, urine and greywater, are often collected separately. Rainwater harvesting and the treatment of organic waste and animal manure can also be integrated into the concepts!! the unnecessary dilution of the flow streams is avoided, for example by using dry, low flush or vacuum transport systems. This minimises the consumption of valuable drinking water and produces high valued concentrations of recyclables.

23 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 23 Sanitising urine Time and Temperature

24 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 24 Sanitising faeces Temperature pH Ammonia Dryness Solar radiation Competition Nutrients Oxygen

25 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 25 Technology examples

26 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 26 overview of ecosan technology-components ecosan technologies

27 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 27 examples of urine diverting toilets Wost-Man, Sweden waterless: faeces and urine without flush Roediger, Germany Dubletten, Sweden GTZ, Mali China dry/wet: faeces without, urine with flush dry/wet: faeces with, urine without flush wet: faeces & urine with flush ecosan system components

28 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 28 Made from concrete in Mexico, Namibia, Botswana.... examples of urine diverting toilets

29 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 29 Indoor UDS in Peru examples of urine diverting toilets

30 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 30 Examples of urine diversion toilet slabs Urine diverting concrete slab Composting toilet with urine separation (China)

31 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 31 Mon Museum, Sweden vacuum urinal KfW-building, Germany waterless urinals ecosan system components Tepoztlan, Mexico South Africa Ethiopia

32 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 32 composting toilet, Germany (Berger Biotechnik) examples of composting toilets Schweden ecosan system components

33 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 33 examples of composting toilets

34 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 34 examples of dehydrating toilets Enviroloo-prefabricated system, South Africa SolaSan-prefabricated system, South Africa various dehydration systems (with and without urine separation) ecosan system components

35 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 35 Prefabricated dry UD toilet - South Africa examples of dehydrating toilets

36 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 36 Solar drying toilet in El Salvador examples of dehydrating toilets

37 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 37 vacuum systems elements: vacuum toilets, vacuum urinals, vacuum conductions, pumping station advantages: water saving, concentrated black water collection, decentralised treatment possible (anaerobic) manufacturer: i.e. Roediger GmbH ecosan system components

38 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 38 vacuum systems Gabarone, Botswana: Decentral wastewater collection using vacuum technology

39 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 39 membrane technology Highly effective removal of soluble and biodegradable materials in wastewater stream selective permeable membrane (pore sizes < bacteria) treated water recycle potential for non-potable application compact, flexible system ecosan system components

40 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 40 anaerobic treatment with biogas production small scale biogas plants: decentralised treatment of household wastewater with or without agricultural waste ecosan system components

41 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 41 aqua culture wastewater treatment by aquatic plants and fish with nutrient recyling by human consumption offers high quality protein at low cost predominantly in Asian countries fish production of 1-6 tons/ha·year) achieved duckweed tilapia carp ecosan system components

42 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 42 Various containers for urine storage: Gebers, Schweden Lambertsmühle, Deutschland urine storage ecosan system components

43 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 43 direct injection of liquid fertiliser dried faeces - soil amelioration) irrigationurban agriculture composting with organic waste agricultural use urban agriculture ecosan system components

44 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 44 Practical examples

45 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 45 Urine diverting concrete slabGreywater garden Experimental on-site sanitation module consisting of a urine diverting dehydrating latrine, shower and greywater garden ecosan pilot projects experimental on-site sanitation in Koulikoro, Mali (supported by GTZ)

46 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 46 Integrated natural ressources management in Botswana (supported by IUCN, DED, GTZ) Introduction of ecosan systems in three communities: dehydration toilets, urine separation and fertilisation of gardens with urine urine diversion toilet made out of plastic Awareness workshop on a village level ecosan pilot projects

47 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 47 participatory development of ecosan solutions in Gibeon and Marienthal, Namibia (supported by GTZ) Information, awareness building, situation and stakeholder analysis Participatory development of ecosan systems Pilot and demonstration units (fixed and movable dehydration toilets with urine diversion) ecosan pilot projects

48 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 48 Traditional urine separating dehydration latrine with infiltration of the urine in the underground through soak pits Upgrading UDS Traditional use of dried faeces, Afghanistan

49 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 49 8 toilet cabins, separate collection of urine, washing water and faeces, co- composting of faeces with paper and organic waste, urine and washing water for fertilizing and irrigation of the banana plantation ecosan public toilet centre Bangalore, India (supported by ACTS, SDC, Uni Oslo and GTZ) ecosan pilot projects source: seecon GmbH

50 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 50 biogas septic tanks Lesotho (supported by GTZ and DED) 1st step (2002): small bore sewer grid for 8 houses, a biogas-septic tank unit, upflow filter based on recycled plastic bottles, wetland, 800m² vegetable and fruit garden, two household connections for the biogas as full cooking energy source 2nd step (2003): field tests of black, greywater and urine separation ecosan pilot projects

51 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 51 Zimbabwe / Mozambique The fossa alterna Source: Peter Morgan, 2004

52 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 52 Urine diversion toilets and waterless urinals GTZ headquarters, main building, Germany GTZ House1 Eschborn, Germany ecosan pilot projects separation, processing and agricultural reuse of urine (implementation 2004/2005)

53 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 53 pig – toilet – biogas – vegetable combined with Greenhouse Production more than times in Northern China Use of nutrients, organics, energy and carbon dioxyde Chinese four in one model ecosan pilot projects

54 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 54 ecosan dry toilet promotion in Guangxi-Province, China Large ecosan project in the phase of up- scaling 1997, pilot project funded by SIDA/Unicef, 70 ecosan (urine diverting dehydration toilets) built in pilot village, Dalu Village 1998, 10,000 urine-diverting toilets were built in 200 ecosan villages in Guangxi 2002, 100,000 ecosan toilets in Guangxi 2003, 685,000 ecosan toilets in 17 provinces (Ministry of Public Health) Factors of success: cultural acceptance, political commitment, technical flexibility, low cost, income generation, pressure from water pollution and water scarcity, promotion and marketing ecosan pilot projects Photos: Sandec, Text: Mi Hua

55 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 55 ecosan-study and reuse experiments in Havana, Cuba (supported by GTZ) Study of options for reuse of urine and faeces in existing urban agriculture in Havana improved soil quality through reuse of organics

56 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 56 ecosan activities supported by GTZ Indonesia India Jordan Turkey Bulgaria Algeria Benin Kenya Lesotho Namibia Zambia China Cuba Burkina Faso Peru Egypt Botswana Mali Yemen Ecuador El Salvador Afghanistan Philippines Germany Vietnam Iran ecosan pilot projects GTZ supported ecosan activities around the world

57 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 57 How would the city look?

58 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 58 urban ecosan concepts Conventional Wastewater System

59 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 59 urban ecosan concepts

60 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 60 urban ecosan concepts food faeces urine greywater drinking water Periphery

61 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 61 urban ecosan concepts

62 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 62 urban ecosan concepts food faeces urine greywater treated greywater drinking water Residential Area

63 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 63 urban ecosan concepts

64 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 64 urban ecosan concepts food faeces urine greywater treated greywater drinking water irrigation of urban green Downtown Area biogas plant vacuum sewerage

65 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 65 Titel des Vortrags, einzeilig oder zweizeilig 65 WfB, Rom – 12.Jan.2005 urban ecosan concepts

66 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 66 Aims of the GTZ-ecosan program To promote the development and pilot application of holistic ecologically, economically and socially sustainable recycling- based wastewater and sanitation concepts in developing countries To contribute to the global dissemination and application of ecosan approaches and establish these as state-of-the-art techniques – in both, developing and in industrialised countries

67 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 67 GTZ – ecosan R&D project 2000:1 st International Symposium on ecological sanitation in Bonn, Germany 2001: start 1 st phase of the supra-regional research and development ecosan-project of GTZ, financed by the German Federal Ministry for Economic Cooperation and Development (BMZ) - development of ecosan knowledge management tools - building up of a global ecosan-network, - initiation of pilot projects 2003:2 nd International Symposium on ecological sanitation in Lübeck, Germany start 2 nd phase of the ecosan-project of GTZ - further development of knowledge management tools - support to the global ecosan-network - implementation of pilot projects

68 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 68 Key activities of the GTZ ecosan program GTZ – ecosan program knowledge management and networking e-newsletter ecosan website ecosan source book (in progress) ecosan-project data sheets (in progress) ecosan-technical data sheets (in progress) brochures, posters, professional articles, films, etc. conferences & workshops cooperation in the field national & international working groups ecosan pilot research and demonstration projects baseline and feasibility studies for sanitation systems, treatment and reuse systems advocacy and decision making workshops training workshops technical and operational advice for implementation accompanying research upscaling of projects and dissemination of experiences more than 40 pilot projects worldwide

69 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 69 main challenges increasing of awareness integration of reuse into planning from the beginning revision of legal frameworks & technical standards establishment of full cost analysis and risk and benefit comparisons finding innovative investors and adapting financing instruments implementation of large scale urban demonstration projects (in Africa large degree of experience with pilot installations - urgent need to go to scale) Source: Petter Jenssen Greywater treatment in Norway

70 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 70 a vision for alternative water management in urban areas future full-scale eco-sanitation systems in urban areas will most probably consist of a spatial multiple layer patchwork of technical and management solutions for: different areas (e.g. different solutions for city centre, commercial zones, individual housing areas, individual building entities, etc.) and different wastewater flows (different solutions for urine, greywater, brownwater or mixed wastewater) have to offer the same or a better level of comfort as the present systems individual and flexible systems adapted to local and frame- work conditions flexible in time: the transition from the standard centralised system to alternative systems will happen stepwise and start from certain patches (e.g. development areas) and for certain wastewater flows (e.g. greywater or urine)

71 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 71 present obstacles for the implementation of new sanitation concepts in urban areas inertia of the existing infrastructure (often designed for 50 or more years) and management systems legal system tailored to centralised end-of-pipe systems principles of source separation and resource recovery not reflected in current discharge standards and environmental laws products from human excreta don´t appear in fertilizer regulations monitoring structures exist only for centralized systems alternatives not yet economically competitive, externalities and risks not reflected in costs of the current system planners not yet familiar with the whole range of technological options and user centred planning methods

72 Ecological sanitation - innovative wastewater management systems Sector Network SOWAS, October 2004, Accra Ghana 72 Thanks for your attention & interest!!! subscribe the ecosan-newsletter by sending an with the text subscribe ecosan to: conclusion


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