Tools for Improved Water Quality Monitoring, Sanitation and Safe Use

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MASTER’S THESIS

MASTER OF SCIENCE PROGRAMME Sanitary Engineering

Luleå University of Technology

Department of Civil and Environmental Engineering Division of Sanitary Engineering

Tools for Improved Water Quality Monitoring, Sanitation and Safe Use

of Human Excreta in Agriculture

Cochabamba, Bolivia

PETRA VIKLUND

STINA WELANDER

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Field Study performed in Cochabamba, Bolivia, during October to December 2006. It was carried out in cooperation with the company Agua Tuya and their clients in the village of Challacaba.

First of all we would like to thank Gustavo Heredia, manager at Agua Tuya for a lot of help and his never ending enthusiasm for new projects, and Lourdes Valenzuela, project co‐ordinator at Agua Tuya, for great help with valuable contacts and for the power of convincing her parents of letting us stay with them. The possibility to stay with the Valenzuela family meant a lot to us – thank you Elisabeth and Ricardo! All the staff at Agua Tuya/Plastiforte for assisting with big as well as small things should also be acknowledged.

We are very grateful to Elisabeth Kvarnström for establishing the contact with Agua Tuya. She also became a valuable co‐supervisor with lots of interesting ideas and encouraging e‐mails. We also thank professor Jörgen Hanæus at Luleå University of Technology for good supervision when we needed it and

“free hands” when we were doing allright without him…

Last but not least a big, big thank you to all the people in Challacaba and especially the people in the water community board, for trusting us and enthusiastically committing to the project.

Luleå, March 2007

Petra & Stina

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Sammanfattning

Idag saknar 1 miljard av världens befolkning säkert dricksvatten och 2,6 miljarder är utan godtagbar sanitetslösning (WSP

¹

, 2006). Detta orsakar stora hälso‐ och föroreningsproblem, speciellt i urbana områden. Enligt FN Habitat (2003) kommer jordens urbana befolkning att öka från 3 till 5 miljarder inom de närmaste 20 åren. I många utvecklingsländer är den kommunala dricksvattenförsörjningen eftersatt och det är vanligt att sammanslutningar av hushåll, s.k. vattenföreningar, står för dricksvattenförsörjningen. Arbetet bedrivs ofta av lekmän och kontroll av dricksvattenkvalitén är ovanligt. För att förenkla arbetet med dricksvattenkvalitet har WHO utarbetat en arbetsgång för vattenkontrollprogram riktat till små vattenföreningar. På avloppssidan har bland andra svenska SIDA sedan tidigt 1990‐tal arbetat med forskningskonceptet ekologisk sanitet (eco‐san) för att påskynda utvecklingen av säkra, robusta och ekonomiska sanitetslösningar. Utmaningen är att skapa system med låg vattenförbrukning, minimerad föroreningsrisk och återföring av näringsämnen till jordbruk.

I Bolivia, Sydamerikas näst fattigaste land, är sjukdomsfall till följd av bristande vatten och sanitet vanligt. Hälsoläget har dock förbättrats de senaste 30 åren i takt med att fler fått tillgång till förbättrat dricksvatten (85 %) och sanitet (46 %). Det bolivianska företaget Agua Tuya har i 15 år arbetat med utbyggnaden av dricksvattennät i ytterstadsområden i Cochabamba. På senare tid har efterfrågan på avloppssystem ökat och därför har ett samarbete med EcoSanRes (SIDA) inletts. I ett pilotprojekt byggs 20 urinseparerande torrtoaletter i Challacaba, Cochabamba. Man planerar även att öppna ett resurscentrum, som bland annat kommer att erbjuda ett kontrollprogram för dricksvattenkvalitet riktad mot småskalig vattendistribution.

Detta examensarbete vid Luleå tekniska universitet ska bidra med verktyg för en förbättrad kontroll av dricksvattenkvalitet och sanitet i ytterstadsområden.

Det innefattar en två månader lång fältstudie i Cochabamba under hösten

2006 samt litteraturstudier i Luleå. Examensarbetet resulterade i ett

kontrollprogram för vattenkvalitet anpassat för små vattenföreningar baserat

på områdesundersökning och förebyggande åtgärder. Analyser och

vattenprover är underordnat dessa instrument där parametrar som bevakar

förändringar i vattenkompositionen såsom pH, lukt och smak prioriteras. I

byn Challacaba uppfördes 19 urinseparerande toaletter. Instruktioner och

rekommendationer för användning, rengöring och tömning av toaletterna,

lagringstider och efterbehandling för fekalier, samt spridning av urin och

fekalier upprättades med stöd av WHO:s rekommendationer. Den

bolivianska lagstiftningen visar inga tydliga hinder för användning av urin

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Abstract

Today 1 billion people in the world lack safe drinking water and 2.6 billion people do not have access to basic sanitation (WSP

¹

, 2006). This causes large health‐ and contamination problems, especially in urban areas. Due to UN Habitat (2003) the world’s urban population will increase from 3 to 5 billions within 20 years. Many developing countries do not have an adequate municipal drinking‐water service and it is common that the water is provided by small water communities. The work is often carried out by non‐

professionals and control of the drinking‐water quality is uncommon. To simplify the work with drinking water control WHO has developed guidelines for water monitoring adapted to small water communities. Since the early 1990’s the Swedish International Development Agency (SIDA) has been working with the concept of ecological sanitation (eco‐san) to advance in the development of safe, robust and economical sanitary solutions. The challenge is to create systems that consume little or no water, minimize the contamination risk and allows recycling of nutrients to agriculture.

In Bolivia, South America’s second poorest country, diseases caused by lack of safe drinking water and proper sanitation are common. The health situation has improved the last 30 years as more people have gained access to improved drinking water (85%) and sanitation (46%). The Bolivian company Agua Tuya has been working with drinking water systems in peri‐urban areas of Cochabamba, Bolivia, for 15 years. During the last years the demand for sanitation has increased and to meet that demand cooperation with the research organization EcoSanRes has been established. In a pilot project 20 urine‐diverting toilets will be built in Challacaba, Cochabamba. Agua Tuya also plans to open a Resource Center that among other things will offer a monitoring program for small‐scale water distribution.

This Master’s thesis at Luleå University of Technology will contribute with

tools to improved drinking water monitoring and sanitation in peri‐urban

areas. It includes a two months field study in Cochabamba during autumn

2006 as well as a literature study performed in Luleå. The Master’s thesis

resulted in a monitoring program for water quality, adapted to small water

communities based on sanitary surveys and preventing acts. Analyses of

water samples are subordinated as parameters measuring changes in the

water quality such as pH, smell and taste are prioritized. In Challacaba 19

urine‐diverting toilets were built. Recommendations for use, cleaning and

emptying of the toilets, storage times and treatment for faeces as well as

spreading of excreta were established in line with WHO’s guidelines. The

Bolivian law does not show any obvious obstacles against the use of human

excreta in agriculture as long as the recommendations are followed.

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Index

1 Background...1

1.1 Water – a valuable resource...1

1.2 Water related diseases...2

1.3 Bolivia and its health situation...3

1.4 The project...6

2 Goal and objectives ...8

3 Scope ...8

4 Method...8

5 Water quality monitoring for small water communities ...9

5.1 Multi‐barriers for safe drinking water ...9

5.1.1 Legislation and policy frameworks ...10

5.1.2 Guidelines, standards and objectives...10

5.1.3 Water quality monitoring and management of water supplies ...12

5.1.4 Public involvement and awareness...13

5.2 Water and contamination sources ...13

5.2.1 Water sources...13

5.2.2 Contamination sources ...15

5.3 Establishing a monitoring program ...16

5.3.1 The Audit approach ...17

5.3.2 The Direct Assessment approach...17

5.3.3. Monitoring microbiological parameters ...18

5.3.4 Monitoring chemical parameters...19

5.3.5 Monitoring physical and aesthetical parameters...19

5.3.6 Sanitary survey...20

5.3.7 Support for small water communities ...21

6 Result and discussion ...22

6.1 Initial phase...22

6.1.1 New wells...22

6.1.2 Old well...23

6.1.3 Tanks and tanker trucks ...25

6.2 Follow‐up ...25

6.3 Action phase ...26

6.3.1 Prioritization and investigation ...26

6.3.2 Information ...27

6.3.3 Acting ...27

7 Ecological Sanitation in peri‐urban areas ...28

7.1 Basic criteria ...28

7.2 Adapting to local conditions ...29

7.2.1 Climatic differences...29

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7.3 Design ...30

7.3.1 Examples of eco‐san ...30

7.4 Pathogen destruction...32

7.4.1 Urine ...32

7.4.2 Primary treatment of faeces ...32

7.4.3 Secondary treatment of faeces...33

7.5 Agriculture...35

7.5.1 Application of urine ...35

7.5.2 Application of faeces ...37

7.6 Legislation and common practice...38

7.6.1 WHO Guidelines ...38

7.6.2 Bolivian guidelines...38

7.7 Education and public participation...39

7.7.1 Cleaning and maintenance ...39

8. Result and discussion ...41

8.1 The building process ...41

8.1.1 Comments ...41

8.2 Soil samples ...42

8.2.1 Comments ...43

8.3 Recommendations for use of the eco‐san toilets in Cochabamba...43

8.3.1 Preparations...43

8.3.2 Cleaning and maintenance ...43

8.3.3 Storage and application ...44

8.3.4 Comments ...45

8.4 Legislation and policy ...45

8.5 Overall comments ...46

9 Conclusions...47

10 Future work ...48

11 References ...49

Appendix

A – Some waterborne diseases

B –

Waterborne pathogens and their health significance

C –

WHO guidelines on chemical hazards in drinking water

D –

WHO guidelines for radiation levels in drinking water

E –

Comparison Bolivian guidelines values – WHO guideline values

F –

Example Sanitary survey

G –

Cost for analyses of drinking water

H –

Design Eco‐san toilet in Challacaba

I –

GPS‐coordinates for soil sampling in Challacaba

J –

Time‐plan for Eco‐san project in Challacaba

K –

Instructiones para usar la orina como abóno

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1 Background

1.1 Water – a valuable resource

As urbanisation, industrialization and populations increase in many developing countries the water resources become more and more valuable. It is not only needed for domestic use for an increasing population but also needed to cover the increasing demand of food and energy production.

Urbanization sets demands on the water as inefficient use and widespread contamination decreases the amount of available clean water. Clean water together with proper sanitation is crucial to avoid transmission of waterborne diseases. Since November 2002 water is also a human right, stated by the UN commission Convention for Economic, Social and Cultural Rights (CESCR).

The General Comment states that: ʺthe human right to water entitles everyone to sufficient; affordable; physically accessible; safe and acceptable water for personal and domestic usesʺ. This means that the 145 countries which have ratified the International CESCR now will be compelled to progressively ensure that everyone has access to safe and secure drinking water (UNESCO, 2003).

All around the world there are more than 1 billion people who lack access to safe water supply

¹

and over 2.6 billion people who live without basic sanitation

²

(WSP

¹

, 2006). Most of these people live in developing countries and the lack of water is strictly bound to poverty, lack of hygiene and malnutrition. To focus attention and mobilize action on key issues for development the UN General Assembly Millennium Meeting in September 2000 established eight Millennium Development Goals (MDGs) to be reached by 2015, from a baseline of 1990. Detailed implementation plans are crucial to meet the global targets as they can only be met via local actions supported by necessary financial resources (UNESCO, 2006). Millennium Task Forces have been established to identify what needs to be done to meet the MDGs and the UN Millennium Task Force 7 on Water and Sanitation has indicated that the targets on drinking water and sanitation will not be reached at the present rate of advancement (UNESCO, 2006). The progress within the drinking water field is evident but the work with sanitation is not keeping up the pace, especially not concerning the development of solutions for urban and peri‐

urban areas. UN‐Habitat (2003) estimates that urban populations will grow from 3 billion today to 5 billion in about 20 years, and that 40% will be living in slums.

1 Improved drinking water is piped water into dwelling, plot or yard, public tap/standpipe,

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The two most wide‐spread sanitation technologies today have obvious drawbacks concerning water quantity used and contamination spreading. The flush‐and‐discharge system requires large amounts of water and often unaffordable investments in pipes and if the waste water treatment is not adequate it only moves contamination further downstream. Another common solution is the drop‐and‐store system which is simple and relatively cheap but requires space to dig new pits every few years and is therefore not suitable in crowded areas. It can also easily contaminate the ground‐water, especially if the ground water table is high (Winblad, et al 2004). Both of these systems efficiently discharge nutrients instead of returning them to agriculture. In the case of flush‐and‐discharge the nutrients often become an environmental problem of eutrophication in rivers and lakes. To meet some of the demands for a sustainable society the Swedish International Development Agency (SIDA) has been working with the concept of ecological sanitation since early 1990’s. The challenge is to create systems that will save water, prevent water pollution and recycle nutrients to a low cost without jeopardising the health situation (Winblad et al, 2004).

As the CESCR stated in November 2002 it is a human right to have access to safe and acceptable drinking water. The quality of the water is rarely controlled especially when dealing with private and community based water sources. In order to increase drinking water quality and decrease water related diseases the World Health Organisation (WHO) works actively with water control and has provided guidelines concerning the establishment of monitoring programmes.

1.2 Water related diseases

The World Health Organisation (WHO

¹

, 2006) has compiled a list of water and sanitation related diseases causing deaths; see excerpt from the list in table 1.1. Some are treatable illnesses but the list also contains drowning, lead poisoning and malnutrition which are related with water but not transmittable. Among the illnesses caused by pathogens diarrhoea is by far the most common. Each year 4 billion cases of diarrhoea occur worldwide and 1.8 million of these have a deadly outcome (WHO

¹

, 2004). Most affected are children under the age of 5.

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Table 1.1. Excerpt from a list of the global burden of disease for the year 2002 (WHO, 2004).

Cause Total number of deaths (thousands)

Diarrhoeal diseases 1 789

Malaria 1 272

Schistosomiasis 15 Dengue 19

Japanese encephalitis 14

Intestinal nematode infections 12 Protein-energy malnutrition 260

Drowning 382

Several other diseases are transmitted by pathogens through contaminated water and although they normally are not deadly they have a severe impact on peoples’ lives. Healthy people better absorb nutrients than people suffering from diseases, particularly helminth infections, and adults who are ill or must care for ill children are less productive (UNESCO, 2006). There are several routes for pathogens to reach a host and the figure 1.1 shows transmission routes from faeces to face. Description of some important water related diseases can be found in Appendix A.

Figure 1.1. Transmission routes from faeces to face (Winblad et al, 2004).

1.3 Bolivia and its health situation

Bolivia is the second poorest country in South America. This is not due to the

lack of natural resources but a consequence of the extremely unequal

distribution of both land and power. The country’s very unstable political

history with more than 189 coup d’états, more than any other country in the

world, is both the result and the cause of this inequality. Since 1982 the

military has been outside the political arena but despite that, few of the

numerous politicians in charge have been successful for more than a few

months. More than half of the Bolivian population is of indigenous origin and

2005 the first indigenous president, Evo Morales, was elected. During his

presidency Bolivia has established a national development plan including the

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recently graduated from university. This implies that environmental work on national level is new and extremely challenging and because of many other problems such as poverty, malnutrition, unemployment, lack of social insurance system etc. it is not the country’s first priority. As can be seen in table 1.2 the total coverage of improved drinking water is fairly high in Bolivia especially concerning the urban areas where coverage is as high as 95%. This does not ensure that the quality of the distributed water is adequate, due to insufficient network standards, or that water is a 24‐hour service. Compared to the drinking water coverage the total coverage of improved sanitation is fairly low; only 46% (UNICEF, 2006).

Table 1.2. The coverage of safe drinking water and improved sanitation respectively (UNICEF, 2006).

Average Urban Rural

Improved drinking water 85% 95% 68%

Improved sanitation 46% 60% 22%

Like in many other developing countries the major sources of disease and death in Bolivia, especially among the young population, are infections caused by poor access to safe drinking water and sanitation (Cortes, 2006), but the situation has improved the last 30‐35 years. The infant mortality rate has decreased with almost 2/3 between 1970 and 2004 when only 54 deaths/1000 live births was reported. Also the under‐five mortality rate has decreased with 70% during the same period and the life expectancy at birth has increased from 46.7 to 63.9 years. Comparing to Sweden, Bolivia still has a long way to go: within the same time the infant mortality rate in Sweden has decreased from 11 to 3 per 1000 life births, see table 1.3 (UNDP, 2006).

Table 1.3. Comparison of health figures between Bolivia and Sweden from the years 1970 and 2004 (UNDP, 2006)

Bolivia Sweden

Year 1970 2004 1970 2004

Infant mortality rate (per 1 000 live births) 147 54 11 3 Under-five mortality rate (per 1 000 live births) 243 69 15 4 Life expectancy at birth (years) 46.7 63.9 74.7 80.1

According to OPS/OMS (2004) 22% of all Bolivian children under the age of

five had periods of diarrhoea in 2003. Between the years of 2001 to 2003 the

number of cases of severe diarrhoea increased with over 150 000 despite an

increased access of both improved drinking water and sanitation facilities in

Bolivia, see table 1.4. Of these cases 80% were recovered in children under the

age of 5. Due to a low frequency of medical attendance the reported cases

might give an underestimated picture of how many cases that truly appears

in the country. Figures from WHO

²

(2006) show that Bolivia in 2001 only had

1.22 physicians per 1000 inhabitants.

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Table 1.4. Reported cases of diarrhoea in Bolivia (OPS/OMS, 2004).

Year 2001 2002 2003

Cases of diarrhoea 541 697 611 982 701 182

During the early 1990’s a major outbreak of cholera took place in the Americas with nearly 400 000 cases resulting in 4 000 deaths (UNESCO, 2006).

Bolivia was also effected by this outbreak and during the period of 1991‐1995, 814 of the reported cholera cases had a deadly outcome, see table 1.5 (OPS/OMS, 2004). Fortunately since 1999 no new outbreaks have been reported.

Table 1.5. Outbreaks and deaths caused by cholera from 1991 to 1993 (OPS/OMS, 2004).

Year 1991-1995 1999-2003

Outbreaks of cholera 40 212 0

Deaths caused by cholera 814 0

According to WHO up to 10% of all people living in developing countries are infected with helminths. A study performed in El Salvador (Corrales et al, 2006) examining the impact of dry‐toilets on the prevalence of helminths and protozoa showed that about half of the study subjects were infected with at least one type of intestinal parasites. Bolivia is no exception concerning the spreading of intestinal parasites although no exact figures are known.

According to Cortes (2006) Pinworm, Roundworm, Dwarf tapeworm, Threadworm, Beef tapeworm, Pork tapeworm and Whipworm are all common to very common. Malaria is transmitted throughout 75% of the country’s area where half of the population is situated. In the year of 2000 34 000 malaria cases were reported, this is a marked decrease since 1998 when 85 000 cases were reported (PAHO, 2007). Malaria is transmitted by mosquitoes that need water to develop. At levels above 2500 m and in large cities there is no risk for transmission of malaria

(CDC, 2005). Also dengue fever is transmitted by mosquitoes and cases of classic dengue fever have been documented in Bolivia since 1987. In 1999 and 2000, 27 and 80 cases of classic dengue were identified, respectively (PAHO, 2007).

Schistosomiasis is transmitted by aquatic snails perforating the skin. The snail is not present in Bolivia (CDC, 2005). In UNDP’s Human Development Report from 2006 it is told that 23% of the Bolivian population was

undernourished 2001/03. This is a decrease since

Figure 1.2. Indigenous woman in

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According to UNESCO (2006) a person’s daily diet for adequate nutrition should be complete (in energy terms) and balanced (in nutritional terms).

1.4 The project

Cochabamba is located 2500 metres above sea level, in a fertile valley between the highland and the lowland. The city of Cochabamba is the third biggest city of Bolivia and this metropolitan area host around 1 million people. The sun radiation is very strong especially during the winter which is the dry season. The rain period consists of the summer months of December‐

February. The temperature ranges between –5° and 25°C in the winter to be more stable around 20‐25° C in the summer. The spring is the hottest time when 30°C is not unusual at daytime and the nights are just slightly cooler.

Cochabamba is famous for “el guerra del agua” (the Water war) which took place in 2000 when the population gathered to get rid of a private company that had taken over the public water supply.

The Bolivian company Agua Tuya has been working with drinking water in local communities in the area of Cochabamba for more than 15 years. They have built more than 150 local systems supplying 85 000 people, and new communities, today served by tanker trucks, come with requests continually. The company has recently started their first sanitation projects and the concept is the same as for the drinking water projects: to build proper and economical systems with simple technique to be owned by its users on the users demand. Working in the communities Agua Tuya see a big demand not only for drinking water supplies and sanitation solutions but also for safe monitoring of the existing water supplies, to maintain and improve the drinking water quality. To support the water communities a Resource Center is established and the purpose of the Center is to be a base for knowledge and experience where the communities get advice concerning water related issues. A specific request from the small water communities concerns the control of the drinking water quality. The traditional water quality analyses set by the Bolivian Ministry for Public works and Services (Ministerio de Servicios y Obras Públicas) include a list of parameters to a cost of one month’s Bolivian salary. One of the first tasks of the Resource Center will be to develop simplified water analyses or monitoring program to a small cost. Challacaba is located in a peri‐urban area of Cochabamba, about one kilometre from a main road, and is one of the communities that first had a water system supplied by the Agua Tuya Programme. In 2005 the community upgraded the system with a hydro‐tower

Figure 1.3. Agua Tuya’s truck.

Photo: Stina Welander

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and new pipes. Having water 24 hours a day of a better quality than in the

town challenged them to seek for sanitary solutions as well. Agua Tuya was

commissioned to take a look at the problem and returned with the suggestion

of urine‐diverting dry toilets. A contact with SIDA’s research‐project on

ecological sanitation (EcoSanRes) was established and EcoSanRes decided to

support the project economically for several reasons. Eco‐san has not before

been implemented in a peri‐urban area. Concerning the lack of adequate

sanitation Challacaba is not unique in the area, the demand is great and the

municipal water and wastewater company (SEMAPA) is not able to extend at

a satisfactory rate which means the potential for enlargement of the eco‐san

project is vast. Agua Tuya’s knowledge within the sanitation field is limited

and for a successful completion of the project help is required especially

concerning the treatment methods. In Sweden the use of urine‐diverting

toilets in summer houses is widespread and a lot of research has been done in

the field. Through a PhD‐graduate of the Luleå University of Technology,

now involved in EcoSanRes, the contact was made with the Agua Tuya

Programme resulting in this Master’s thesis in Environmental engineering at

Luleå University of Technology.

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2 Goal and objectives

The overall goal is to provide people in peri‐urban areas in Cochabamba, Bolivia, with tools, increasing their possibilities to control and improve their water and sanitation in order to achieve better health and living conditions.

The specific objectives of this Master’s thesis are to:

• Design a work procedure for water quality monitoring adapted to small water communities.

• Follow and describe the building of twenty urine diverting eco‐san toilets performed by the Agua Tuya programme and villagers of Challacaba, Cochabamba, Bolivia.

• Give recommendations on safe use and maintenance of urine diverting eco‐san toilets in Cochabamba, Bolivia.

• Present proper methods, adapted to local conditions, on how to use human excreta in agriculture.

• Compare Bolivian legislation concerning use of human excreta in agriculture with proposed methods.

3 Scope

The design of the water quality monitoring programme is established for small water communities (100 – 1000 households) in peri‐urban areas. It is based on health parameters and does not consider technical parameters.

Water sources such as surface water, spring water and shallow dug wells are uncommon in the urban Cochabamba area and will not be dealt with concerning the development of the drinking water quality. The concept of proper methods in the use of human excreta in agriculture mainly aims at decreasing the risk of disease transmission, increasing the yields is important but subordinated.

4 Method

The project involves a field study in Cochabamba, Bolivia, during October –

November 2006 and includes monitoring, sampling and interviews with local

physicians, agricultural engineers, local personal and villagers. A parallel

literature study concerning water quality monitoring, eco‐san and agriculture

has been conducted from September 2006 to February 2007.

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5 Water quality monitoring for small water communities

The surveillance of water quality in any distribution of drinking water is an important element for the development of strategies for improvement of the security of drinking water. Strategies for collecting, analysing and summarizing data and reporting the findings must be developed and followed by recommendations on possible actions. Surveillance of water sources is important for all kinds of water suppliers whether they are public, community or private actors (WHO, 2004). The definition of small water communities refers to non‐municipal associations of 100 to 1000 households that provide drinking water for their own use.

5.1 Multi-barriers for safe drinking water

In order to secure water quality for small water communities it is important to look at the supply system including source, distribution network and tap. The multi‐barrier approach is an integrated system of procedures, processes and tools that collectively prevent or reduce the contamination of drinking water from source to tap in order to reduce risks to public health (Canadian Council of Ministers of the Environment, 2002). The approach concerns three major elements for producing safe drinking water and these include source water protection, drinking water treatment and safe drinking water distribution. To address these elements following tools can be applied:

legislative and policy frameworks

guidelines, standards and objectives

water quality monitoring and management of water supplies

public involvement and awareness.

(Canadian council of Ministers of Environment, 2002)

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Concerning water supplies for small communities it is rather rare for drinking water to be treated before distribution when this often is related to high costs.

Drinking water treatment may involve microbiological barriers such as sand filtration, membrane filtration, chlorination, UV‐treatment etc. Due to the absence of these barriers the two remaining elements, source water protection and safe drinking water distribution becomes of great importance when establishing a reliable drinking water monitoring system for small water communities.

5.1.1 Legislation and policy frameworks

It is important that legislation and policy framework that address the matter of safe drinking water at all levels support public health goals. According to Bolivian legislation the supplier of drinking water is obliged to guarantee the quality of the service that is received by the user following the current norms and regulations (Government of Bolivia, 2000). Although the responsibility of the quality of the water is in the hands of the supplier, the government of Bolivia declares in the National Development Plan (Government of Bolivia, 2006) that water is the responsibility of the state, both as a natural resource and food necessity. This declaration suggests that the responsibility is shared and is to be applied on national, regional and community level.

5.1.2 Guidelines, standards and objectives

Guidelines and standards are tools to assist system managers and management personnel in order to fulfil their responsibility to deliver drinking water of good quality to their customers. The guidelines are often divided in three parts. Ons part concerns the technical aspect of water quality in order for the system to function properly, another part is regulating the aesthetics of the water such as odour, taste and colour and a third, and most important part, handles the hygienic aspects, see table 5.1.

Table 5.1. Aspects of drinking water quality.

Technical Aesthetical Hygienic corrosion

precipitation clogging

smell taste turbidity colour

pathogens

other compounds that might give rise to health problems

Box 1. Case study: Cochabamba - legislation

In Bolivia as in many developing countries the national laws are not always applicable as the practice differs much from the theory both concerning knowledge and economy. The Bolivian guidelines for water quality are very strict, various parameters have lower guideline values than WHO, see Appendix E. The way the norms and standards for drinking water quality are formed will imply that thorough testing is needed to respond to the legislation. In fact this is an impossible burden for the small and often economically weak water communities. Strict guideline values also decreases the possibilities for water to pass the analyses without remarks and in most cases this will imply that no testing at all is carried out. For costs of a typical analysis see Appendix G.

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WHO guidelines

The World Health Organisation (WHO) provides guidelines on how to assess safe drinking water (2006). According to these guidelines the greatest risk of contamination of drinking water comes from microbes originated from human and animal excreta. The WHO guidelines are health‐target based, which includes

Health outcome targets such as measuring a reduction in the overall risk of disease

Water quality targets represents the health risk of long‐term exposure to specific concentrations (guideline values) in drinking water

Performance targets when short‐term exposure represents a public health risk where large fluctuations can occur over short periods with significant health impacts

Specified technology targets identify specific permissible devices or processes for given situations for generic drinking‐water system types.

These targets are applied on the different hazards connected to drinking

water meaning microbial, chemical, radiological and aesthetical hazards. In

the guidelines waterborne pathogens are listed and their health significance is

rated in a scale from low – moderate – high, see Appendix B. The guidelines

also contain a summary of chemical hazards where they are subdivided into

groups considering their origin; natural, industrial or agricultural etc see

Appendix C. The guidelines focus on the importance of local prioritizing

meaning that only the most probable and important compounds should be

included in a monitoring programme. Concerning radiation levels all possible

radio nuclides are listed and presented with a guidance level (Bq/l) see

Appendix D. The acceptability aspects such as appearance, taste and odour

may not in themselves be health hazards but are of great importance as they

undermine the confidence of the consumer. These parameters should be

acceptable to the consumer in order for him to choose this source of water

instead of maybe using other more insecure sources (WHO

³

, 2006).

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Bolivian guidelines

The Bolivian guidelines for safe drinking water published by the Ministry for Public works and Services are meant to;

protect the public health by defining and determining water quality parameters with suitable levels, based on risk principles, with the intention of offering suitable water for human consumption

be applicable throughout the country, taken into account the analytical capacity of the existing laboratories and the techno‐economical conditions of the drinking water operators

establish parameters in order to control and monitor the drinking water quality, within the current national conditions, without jeopardising public health.

In the Bolivian system the characteristics are sorted and defined as shown in table 5.2.

Table 5.2. Characteristics of drinking water, Bolivian guidelines.

Microbiological Chemical Physical Radioactivity Aesthetics Presence of

bacteria or other micro organisms harmful to human health.

Presence of elements or chemical, organic or inorganic compounds in concentrations that may be harmful to human health.

Presence of compounds that affects the properties of water quality such as; colour, turbidity, total solids etc.

Presence of radioactive elements.

Presence of taste, odour and colour that affects the

acceptability of drinking water.

For the absolute guideline values and a comparison between WHO guidelines and Bolivian guidelines see Appendix E (Ministerio de Servicios y Obras Públicas, 2004).

5.1.3 Water quality monitoring and management of water supplies

Traditionally the approach on monitoring has been the technique of

compliance monitoring that relies on sampling of small amounts of water in a

drinking water system and testing those samples for the presence of known

and quantifiable organisms or contaminants (Canadian council of ministers of

the Environment, 2004). In most small water communities the management

and monitoring of water supplies are handled by non‐professionals. High

technology equipment and complicated analyses are in most cases

economically impossible to enforce in these systems. Instead of these high

cost monitoring tools, focus should be on the prevention of contamination

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such as water source protection and functioning distribution networks making sure that the contact between the contamination source and the drinking water is minimized. The integration of surveillance of waterborne disease outbreaks should also play a significant part when providing safe drinking water in small water communities. The definition of a community drinking‐water supply mainly concerns the administration and management arrangements and can include simple piped water systems with sources

such as boreholes with hand pumps, dug wells and protected springs.

Concerning implementation of monitoring programmes for these kinds of water supplies there are some significant limitations such as lack of capacity and skills within the community to undertake process control and verification as well as the very large number of widely spread supplies.

Box 2. Case study:

Cochabamba – present situation

In the Cochabamba peri-urban area small water communities is very common. The small water communities vary in size from serving 100 up to 500

households. They mainly consist of a piped distribution network where each household have their own tap and water meter. The distributed water is very rarely treated for disinfection. In some cases chlorination occurs.

5.1.4 Public involvement and awareness

Contamination of drinking water is often a result of human activity. To decrease the risk, public information and education are of great importance.

This includes information about the relation between personal hygiene and safe drinking water and the impact on the water source from activities such as agriculture, industry and waste management. When creating a well functioning monitoring system in small communities the involvement of the public is a key issue when it comes to reporting on diarrhoea outbreaks or other health concerns that might be related to a contamination of the water source.

5.2 Water and contamination sources

How to handle the first barrier in the multi‐barrier approach, water source protection is dependent on the type of water and possible contamination source present.

5.2.1 Water sources

Dug wells

The open or poorly covered shallow dug wells appose the greatest risk for

contamination when inappropriate water‐filling devices are used. Also faecal

contamination from latrines, septic tanks and farm manure are more common

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agriculture, pesticides and nitrates are increasing problems for small community wells (WHO, 1997).

Borehole wells

Drilling for water makes it possible to reach deep aquifers that are less likely to be affected by contamination from land or surface waters, but depending on the bedrock the water may have high contents of natural contaminants.

Water from deep borehole wells is normally free from microbiological contamination and the water may be used by small communities without treatment (WHO, 1997).

Surface water

The use of surface water as drinking water source is mostly dependent on pre‐treatment before distribution. Surface water is often a recipient for sewage pipes, agricultural drainage etc contri‐

buting to contamination.

Figure 5.2. Rocha River, Cochabamba, Bolivia Photo: Petra Viklund

Spring water

A spring used as drinking water source needs to be of adequate capacity in order to supply the dependent households on an every day basis. Exposed springs are vulnerable to contamination from human and animal activities.

The usual contamination sources are mainly barnyards, sewers, septic tanks and cesspools located higher than the spring (WHO, 1997).

Tanks and tanker trucks

In some areas water is very scarce and it is not possible to dig or bore wells to fill the people’s need of drinking water. In these areas tanks and tanker trucks are used to provide water to the residents. The tanker trucks transport water from other areas and usually fill up big tanks from which the water is distributed in small networks to the households. In areas where drinking water networks do not exist, small household water tanks are used and the tanker trucks distribute water to each household. Due to the uncertainty of the source of the water, the transportation and handling of pipes filling the tanks the risk

Box 3. Case study:

Cochabamba – water sources Water sources

The surface water in streams and rivers in Cochabamba is highly contaminated and partly dries out during the winter months. Therefore the most common drinking water source is a deep borehole well. In the dry hillside peri-urban areas the distribution of drinking water via tanks and tanker trucks is common. The trucks fill their water tanks from private wells located all around the town of Cochabamba.

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of contaminating the tank water is greater than when the water is distributed straight from the source. If the community has several companies serving them or several different trucks from the same company it becomes more difficult to control every potential contamination risk. A regulated water quality control program is therefore of great importance to ensure the people using the source that their water is safe (WHO, 1997).

5.2.2 Contamination sources

Soil and bedrock

Most of the naturally occurring chemical substances that may cause health problems are inorganic. These inorganic substances originate from bedrock and soil that in contact with water under a period of time, releases particles and compounds. It is more likely to occur in semi‐arid and arid climates where the groundwater flow rates are low and the use of groundwater as drinking water source is widespread. The most common health hazards of naturally occurring chemicals in drinking water are arsenic, fluoride, selenium and nitrate. A long‐term exposure of arsenic and fluoride is a major cause of chronic disease, disablement and premature death (WHO

³

, 2006).

Human and solid waste

Human waste is the term used to determine the by‐products of digestion such as faeces and urine (Wikipedia, 2007). The most common contamination of drinking water is faecal contamination caused by poor sewage (WHO

³

, 2006).

Faecal contamination can cause severe viral and bacterial diseases. Leachate from solid waste may contain heavy metals, nitrites and nitrates. Heavy metals accumulate in the human body and may after long‐term exposure cause nausea, skin rash and damage to the inner organs. The compounds of nitrite and nitrate are often

considered together due to the shared toxicological effect and mechanism of action (WHO

²

, 2004).

Nitrate and nitrite can cause Blue baby syndrome (methaemoglobinemia), the reduction of ability for blood to carry oxygen, especially with bottle‐fed infants (Super et al, 1981).

Figure 5.3. Solid waste disposal in Caracara, Cochabamba, Bolivia Photo: Stina Welander

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Agriculture

The overuse of chemicals in agriculture may lead to elevated levels of pesticides in nearby water sources (WHO

³

, 2006). The normal pathways of pesticides entering water sources are via percolation of contaminated runoff to surface water or by leaching to groundwater (WHO

²

, 2004). A number of pesticides/herbicides, specified by WHO, can be directly harmful and carcinogenic to humans. Normally pesticides are found in trace levels which are not acute toxic to humans but may cause chronic health problems (Trautmann et al, 2007). Another health impact connected to agriculture is the leaching of nitrates and nitrites from excessive use of fertilizers into water sources. This will occur where there is insufficient plant growth to take up nitrogen and there is a net movement of water from the root zone. These compounds are health threatening especially to infants causing the so called Blue baby syndrome, see section on Human and solid waste.

Box 4 Case study: Cochabamba- contamination

In some parts of the Cochabamba area the bedrock contains high levels of iron and manganese. These metals do not constitute any health risk to humans but colours the water and gives it a distinct smell and taste. Agriculture is very common in the area but due to high costs chemical additives like pesticides and herbicides are not widespread.

Concerning irrigation sewage water is used frequently with or without pre-treatment. Due to the wide spread agricultural activity in the area the industry is mainly occupied with food production. Mining is a big important industry in Bolivia but is not present in the Cochabamba area. In terms of human and solid waste the treatment of sewage is poor and solid waste is disposed in landfills without sorting.

Industry

Mining and mineral processing activities may when not properly managed cause contamination of drinking water by increased levels of heavy metals and mineral‐processing chemicals. Heavy metals like lead, cadmium and mercury may accumulate in the human body and after long–term exposure cause cancer. In areas where small‐scale industry is the rule it can be hard to monitor the effluent from all the industries. It is then important to monitor the industries with the most impact on water resources such as chemical, metal, textile dying, tannery, paper and pulp, electroplating and printed circuit board manufacturing (WHO

²

, 2004).

5.3 Establishing a monitoring program

According to WHO guidelines on drinking water quality (2004), a monitoring

program may have different approaches. It can either be audit based or rely

on direct assessment.

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5.3.1 The Audit approach

The audit approach is dependent on the water supplier to undertake the verification testing with a third party auditing to verify the results. The supplier may consult expertise to assist in the every day surveillance activities such as sampling and analytical services. The supplier should be able to provide the surveillance agency with system information whenever asked for.

The surveillance agency must possess a stable source of expertise and capacity in order to perform the surveillance on the field, respond to and advise improvement in the water distribution. The audit implementation can be illustrated in table 5.3.

Table 5.3. The audit approach – distribution of responsibilities. (WHO², 2004)

Supplier Surveillance agency

establish a Water Surveillance Programme (WSP)

implement the WSP perform verification testing provide surveillance agency with adequate information concerning system performance

review and approve Water Surveillance Programme (WSP)

undertake or oversee auditing of implementation of individual WSPs as a programmed routine activity

respond to, investigate and provide advice on receipt of reports on significant incidents

5.3.2 The Direct Assessment approach

For the direct assessment approach the surveillance agency carries out independent testing of the water supplies. This method implies that the surveillance agency has access to analytical facilities and trained staff for carrying out the testing but also the capacity to report and communicate the results to the suppliers and communities. In this case the supplier has no function concerning the surveillance but is responsible for the everyday operation of the water supply. Implementation of the Direct Assessment approach is visualized in table 5.4.

Table 5.4. The Direct Assessment approach – division of responsibilities. (WHO², 2004)

Supplier Surveillance agency

operate the daily service of the water

supply specified approaches linked to the diversity

of water supplies

sanitary inspections carried out by qualified personnel

sampling carried out by qualified personnel tests conducted using suitable methods reporting findings and follow ups to supplier

When establishing and implementing a monitoring programme a mixture of

both Audit and Direct Assessment approach is normally used.

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Box 5. Case study: Cochabamba, Bolivia

Surveillance responsibility

According to Bolivian legislation the responsibility for the quality of the provided drinking water lies on the supplier, but the state is responsible for providing drinking water to all as a food necessity. The small water communities lack the ability and knowledge to follow through an audit based monitoring program on their own and at the same time the Bolivian authorities are not fulfilling the requirements for providing a monitoring program based on the direct assessment approach.

5.3.3. Monitoring microbiological parameters

Properties of pathogens

Pathogens can be defined as microorganisms that cause disease. This definition includes bacteria, viruses, fungi, protozoa and helminths (NE

¹

, 2007). Even though pathogens will have different kinds of appearance and transmission routes they have some similar properties when appearing in water.

Pathogens are discrete and not in solution.

Pathogens are often clumped or adherent to suspended solids.

The likelihood of infection depends on the invasiveness and virulence of the pathogen but also on the immunity of the individual.

Pathogens multiply in their host or food or beverages.

Pathogens are not cumulative. (WHO

³

, 2006)

Indicator bacteria

When water is contaminated with faecal matter it would be very challenging to distinguish all polluting agents on a routine basis. The testing for indicator bacteria serves as a tool to control whether a water is contaminated or not but does not prove that water‐borne disease is present (Cairncross, 1993).

Characteristics for adequate indicator bacteria are:

readily present in high numbers in the faeces of humans and warm‐

blooded animals

readily detected by simple methods

should not grow in natural waters. (WHO

³

, 2006)

The Escherichia coli (E‐coli) bacterium is a well known indicator for detection of faecal contamination in drinking water. E‐coli is a subgroup of the total coliform group and will always be present in faeces. The majority of E‐coli are not pathogenic but some strains may cause diarrhoea (Cairncross, 1993).

The total and faecal coliforms can be distinguished by temperature. Total

coliforms are detected at a temperature of 37

^o

C. Faecal coliforms are more

resistant to heat and will therefore be detected at a temperature of 44

^o

C

(Cairncross, 1993).

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Treated water supplies

In treated water supplies where chlorine is used as disinfectant the expected result is to eliminate all coliforms. Bacteria present after chlorination gives an indication of a malfunctioning process that needs to be investigated (Cairncross, 1993). Another approach is to test for chlorine residuals instead of faecal coliforms. The chlorine residuals assist in preventing contamination of drinking water in the distribution system and storage. If no chlorine residuals are present it may indicate that post treatment contamination is occurring (WHO

³

, 2006). Testing for chlorine is in many ways simpler than testing for coliforms and can be done more frequently (Cairncross, 1993).

Untreated water supplies

When controlling the microbiological state of drinking water, the interesting part is to know whether faecal contamination occurs within the system. In untreated water supplies the presence of bacteria is much greater than in treated supplies. Nearly all of these bacteria will be of no health significance to the public and therefore it is even more important to look for bacteria with a definite faecal origin. Verifying results from bacteriological analyses is difficult due to natural fluctuation of bacteria concentration in water supplies where chlorination is not used and the fact that cross‐contamination from hands easily occurs. A bacteriological analysis does not indicate the source of contamination and is therefore quite pointless if one has not decided what to do with the result. In small water communities this leads to the conclusion that it might not be of interest to test for bacteria at all (Cairncross, 1993).

5.3.4 Monitoring chemical parameters

Most chemicals that will be found in drinking water are of health concern in the longer perspective, which means an exposure rate of years rather then months. Analyses of chemical parameters are complicated and expensive and due to the many different sources of chemical parameters such as bedrock, industries and agriculture, a pilot study of the area is of interest before defining what parameters to analyse (WHO, 1997). After the pilot study the parameters can be narrowed down to only a few very strictly health‐related parameters, for example nitrite, chlorine and sulphate. Chemical parameters differ from microbiological parameters as they are more likely to be homogenous in the water body while microorganisms can grow and affect selected parts of the system.

5.3.5 Monitoring physical and aesthetical parameters

Physical parameters such as turbidity, pH, and electric conductivity provide a

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water to the consumers. Concerning turbidity in small community water supplies the exact figure is not very important and visual methods that are based on extinction (use of turbidity tube) are adequate. If the turbidity is no longer visual to the human eye, lower than 5 NTU, electronic meter equipment can be used to measure changes (WHO, 1997). Colour in drinking water may originate from organic substances, metals or coloured industrial waste. No specific equipment is needed. These parameters should be measured both close to the water source and at the end of the distribution system (WHO

³

, 2006). All these parameters are fairly low cost to analyse and can therefore be included in routine controls.

5.3.6 Sanitary survey

The purpose of performing a sanitary survey is to establish the potential risks of contaminating the drinking water from the source to the tap, in order to eliminate parameters that are irrelevant and include parameters that might exist in the drinking water. The sanitary survey will deal with the issue from the two barriers set to limit contamination of the drinking water source, water source protection and the distribution network. Water source protection will include inspection of the area surrounding the water source with emphasis on:

water source characteristics such as bedrock, depth, max‐min flow rate

fencing

latrines and sewage

agricultural activities

industrial activities.

(WHO, 1997) The inspection of the distribution network will include:

possible leaking points in pipe network

reservoir condition, leaking, cracks, air vents etc.

tap stand condition

accumulating of water near the tap stand.

(WHO, 1997)

The WHO has given examples of how such a survey could be designed to suit all kinds of drinking water sources. The system is based on questions that have a yes/no answer and the safety of the source are given points from 0‐10.