D022 - Penduka (Namibia): Sufficient quantities of water and safe drinking water for Penduka
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Introduction: We have been busy for the last couple of months for this project. It contains a fully working water purifying system for the Penduka project in Namibia. We chose this project because we thought it was a very interesting subject and we knew nothing about it. After choosing this assignment we discovered that purifying water is a complex process. In our daily life we have no idea how special clean water is. We drink, shower, flush the toilet and even more with clean water. Have a look at these facts and think again when you shower for 15 minutes.
663 million people lack access to safe water. (1 in 10) 2.4 billion people lack access to a toilet. (1 in 3) More people have a mobile phone than a toilet. Globally 1/3 of all schools lack access to safe water and clean sanitation. Nearly 1 out of every 5 deaths under the age of 5 worldwide is due to a water related disease.
(Source http://water.org/water-crisis/water-sanitation-facts/ / http://thewaterproject.org/water_stats) Clean water is not self-evident. So reconsider your lifestyle and help the people who really need it. By investing in clean water alone, young children around the world can gain more than 413 million days of health (Source www.who.it/water_sanitation_health/wsh0404/en/ ) According to the World Health Organization, for every $1 invested in water and sanitation, there is an economic return of between $3 and $34 !
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Table on contents: 1. Front page 2. Introduction 3. Table on contents 4 – 7. Sam timetable 8. Shane timetable 9 – 14. Namibia general information and climate 15 – 19. Culture and politics 19 – 20. Waterborne diseases 21 – 23. Penduka project 24 – 27. Water composition 28 – 36. Water purifying methods 37 – 47. Building the pre filter 48 – 54. Building the slow sand filter 55. Conclusion 56 – 66. Mail 67 Reflectie Sam 68 Reflectie Shane
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Sam timetable 10 +- Uur Week 36 Geen specifieke data bekend.
Week 38 20 minuten
Week 39 3 uur
Week 40 2 uur
Week 40 20 min
-Gebeld met Oase. -Gemaild met prof. Sibers. -Ingelezen over UV en chloor reiniging. -Contact gezocht met H.W.J Damen over onderzoeks laboratoria. -Met de TOA’s gepraat over het monster. -Begin gemaakt van deelvraag over bestandsdelen van het monster. -Met C. Karssen gepraat over problemen met World School. - M. Bikker gevraagd om ons Engels te verbeteren van de PWS, is akkoord gegaan. Analyse Lab, Vitens en KWR Watercycle Research Institute gevraagd voor hulp. Ze zijn allemaal niet bereid te helpen en sturen maar wat door. Niemand reageerde dus ik heb rond gebeld i.p.v mailen. Ongeveer 10-12 bedrijven / instellingen. Niemand wilde het gratis doen dus nog wat aparte locaties gemaild. Vitens Leeuwarden wil ons helpen en daar hoor ik meer van in week 40. (edit 30-11-15) Het enige bedrijf dat misschien wat wilde doen was Oase omdat ze nu klaar zijn met de verbouwing (Oase in Lexmond). Maar omdat het water weg is maakt het nu nog weinig uit. Stukje toegevoegd aan deelvraag 1. Dit ging vooral over manieren om water te filtreren. (edit 30-11-15) Dit ging vooral over methodes die we toch niet gebruiken omdat ik veel later erachter ben gekomen dat die methodes helemaal niet goed zijn. Je kan ook zien dat mijn mening veranderd door de PWS heen. gemaild naar en Practica.org en http://practicalaction.org/ ja dat zijn verschillende bedrijven. Ook nog wat andere bedrijven die meneer Karssen via de mail had gestuurd. Ik heb ze gevraagd voor een mail adres voor hulp met water zuivering technieken. (edit 30-11-15) Nooit van ook maar 1 bedrijf een mail terug gehad. Ze lijken allemaal verlaten en waarschijnlijk kijkt niemand de 4
Week 41 6 oktober 2015 8 uur
26-1 november 6 uur
26-1 november 2 uur zoeken en rondvragen
9 november 5 uur
14 november 5 uur 15 november 5uur Incl gesprek en lezen.
16 november 1.5 uur 17 november 3 uur
mail en/of boeit iemand het dat wij hen hebben gemaild. Maar verder gaat alles volgens plan dus prima. Wel jammer dat we gewoon geen 1 mail hebben gekregen. Naar Delft voor worldschool. Het was een lange reis maar het was best leuk daar. We ontmoette andere leerlingen die worldschool doen en we hebben met de leerlingen van de technische universiteit van delft gepraat. Ook hebben we hulp gekregen met wat we precies nog moeten onderzoeken. Deelvraag 1 afgerond omdat niemand ons wilde helpen om het te onderzoeken. Uiteindelijk goed contact gekregen met Oase omdat ze eindelijk klaar zijn met hun verbouwing. Zij waren bereid om ons te helpen. Ook verder gegaan met filtratie methodes. Tevens veel geschreven over coliforms en hoe je zelf onderzoek kan doen. Erg interessant en je kan het zelf uitvoeren. Dat is erg gunstig omdat niemand ons wil helpen. 1 van de TOA’s die het niet toegeeft heeft ons water weggegooid die wij bij de presentatie wilde gebruiken. Niemand wil het toegeven en het is erg vervelend omdat ik een manier heb gevonden om te onderzoeken hoe vies het water is en hoe erg. Dat kan je zelf doen maar helaas kan dat nu niet meer. Maar we kunnen er niks aan doen dus we gaan verder. Verder gewerkt aan deelvraag voor de filtratie methodes. En gelezen over allerlei soorten die wij kunnen gebruiken. Verder gewerkt aan slow sand filters en gezocht naar methodes hoe je zelf water kan onderzoeken. Daar heb ik ook over geschreven. Gepraat met een expert in Canada die ik ontmoet heb ik een game die ik speel genaamd Elite: Dangerous. Hij heeft meer informatie en links gegeven over slow sand filters. We hebben een uitgebreid gesprek gehad en heb er erg veel informatie uit gehaald. Door hem ben ik ook dieper gaan na denken of UV wel een goede oplossing is. Slow sand filters zijn veel beter om te gebruiken en ga ik ook veel over lezen. Gelezen over slow sand filters Gewerkt aan slow sand filters en na gedacht over het eind product. Het eindproduct is een lastig iets omdat het zwaar is en er moet dus goed nagedacht worden over hoe we dat aanpakken. Tijdens het nadenken concludeerde
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24-29 4 uur
30 november 1 uur
2 december 4uur
5-12-15 10 minuten
5-12-2015 10 uur
ik onderander dat we het terplekke moeten maken of op een erg kleine schaal. Gepraat met reddit user : W45PN35T. Hij is
een expert op het gebied van rioolwater filtreren uit Amerika. Ik heb hem ontmoet via reddit. Ook hij zei dat het veel beter is om slow sand filters te gebruiken en dan het inderdaad lastig is om te verslepen omdat dat het ritme verstoord omdat het natuurlijk biologisch is. Ook heb ik heel veel filmpjes gekeken over hoe je een design maakt voor een water installatie en het is best lastig. Ook heb ik verder na gedacht over mogelijke modellen. Kreeg een mail dat het logboek niet uitgebreid genoeg is en probeer het aan te passen. Verder zoek ik nog een stukje op over slow sand filters en probeer de nodige elementen nog toe te voegen. Ik heb nagedacht en uitgelegt hoe we het filter gaan maken. Ik ben erachter gekomen dat we gewoon een goedkoop filter moeten maken als demonstratie. Ik ben bezig geweest met het plan maken en hoef het alleen nog uit te voeren. Ook moet ik nog de benodigdheden zoeken. Dit is tevens de volgende deelvraag : hoe gaan we het filter maken. Christien gemaild voor attributen. Dat is leuk voor de stand op de presentatie avond en de worldschool avond. Ik heb het over posters, folders en misschien wel wat die vrouwen daar maken. Omdat Shane sinterklaas viert dit en volgend weekend heb ik besloten om het pre filter alvast te gaan maken. Anders duurt het te lang. Ik heb moeten fietsen naar de Lek voor zand en heb alles gefotografeerd. Ik heb stap voor stap uitgelegd wat ik doe en hoe ik het doe in de deelvraag. Omdat ik alleen was heb ik een statief met een Canon camera gebruikt en veel timers wat erg onhandig is. Het kan zijn dat sommige fotos een beetje uit focus zijn. Maar een Nikon fan ziet dat waarschijnlijk niet ;) Ook heb ik een plan gemaakt voor het slow sand filter. Wat ik nu heb is een prefilter. Ik wil graag dat dat slow sand filter gesponsord word door Hubo Meerkerk en daar ben ik nu in gesprek mee. Het gaat over een 2 tonnen en 1 zak zand + een kraan.
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7-12-2015 5 uur
13-12-2015 6uur
15-12-2015 1uur
Vakantie ?? uur 3-1-2015 3 uur
Tevens ben ik vaak naar buiten gegaan om de benodigdheden te halen zoals zand bij de Lek, grind etc. Begonnen aan het maken en schrijven over het process van Slow Sand Filters. Ik ben naar Biermans geweest omdat het gesponsord laten krijgen te lang duurt. Ik heb daar 1.5 meter PVC en 3 kopstukken gekocht. Zelf had ik de plastic doos al. Ik ben al begonnen met meten en heb het al in delen gezaagt. Morgen maar ik het af. Ik heb dit ook weer zelf vastgelegd met camera + statief. Ben ook al begonnen met het maken van het do it yourself stap voor stap net als bij het pre filter. Shane was bij mij en we hebben alles bij elkaar gedaan, deel van intro gemaakt, wat dingen aangepast en het slow sand filter proberen te maken. Compleet gefaald en de doos is gebroken. We moeten daarom een nieuwe doos kopen en het opnieuw proberen. Bij het boren kwam er een barst in. Daarom gaan we het in de kerstvakantie opnieuw proberen. Feiten bij het intro gevoegd en sources bij de stukjes van mijn deel geplaatsts. Die was ik vergeten erbij te zetten maar had het in een apart bestand gezet. Ook begonnen met het ik naar wij veranderen. Het project afgerond en het slow sand filter gemaakt. Conclusie samen met Shane gemaakt en wat dingen verbeterd. Ook de reflectie geschreven en belangrijke emails bij elkaar gevoegd. Tevens nog meer I’s vervangen en geprobeert wat subjectief weg te halen. Ook de table of contents weer vernieuwd omdat die niet meer klopte.
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Tijdpad PWS Namibië Shane Konijnenberg 5H2 Week 36 + 37 2015 10 uur
27-09-2015 5 uur
Oktober 2015 15 uur
Gemaild over het plaatselijke klimaat naar: Dr. J. Zeidler van SASSCAL ( 1-09-2015 ) Contactpersoon van Namibian Meteorological Service ( 2-09-2015 ) Abiatar van world school ( 31-08-2015 ) Contact opgezocht met E. Diggelen over klimaat Overlegt met S. Vruggink en C. Karssen over Worldschool en problemen met Worldschool Begin maken van deelvraag 1 over climate Maken tijdpad PWS Verder met deelvraag 1 geschreven over het klimaat in Namibië vanaf summer in Namibia tot Winter in Namibia. Veel informatie opgezocht. Gewerkt aan deelvraag 1 over klimaat in Namibië afgerond met de geography. Overlegt met Sam over hoe en wat we allemaal precies nog moeten doen.
November 1e week 2015 5 uur
PWS dag op de TU Delft Verder gegaan met deelvraag 1 begonnen over agrigulture and herding in Namibia. Geschreven cropfarming and forestry.
November 2e week 2015 5 uur
Verder met deelvraag 1 over irrigation and herding. Agriculture afgerond.
November 3e week 2015 6 uur
Begonnen aan culture and politics. Geschreven over de inheemse stammen van Namibië afgerond Gewerkt aan deelvraag 1 over de cultuur ( flag languages) en over waterborne diseases Tijdpad bijgewerkt op verzoek van C. Karssen. Geschreven over waterborne diseases en the Penduka project in deelvraag 1
November 4e week 2015 2 uur 1-12-2015 2 uur
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2-12-2015 1 uur 6-12-2015 3 uur
Geschreven over the Penduka project in deelvraag 1 afgerond ( gender equality toegevoegt aan culture and politics ) Tijdpad bijgewerkt. Deelvraag 1 doorgewerkt, typfouten eruit gehaald, spelling gecontroleerd. Informatie over de Himba people bijgevoegd.
Namibia general information Windhoek is the capital of Namibia with a total of 322.500 inhabitants. Namibia has a total of around 1.8 million inhabitants, with an average of 2.1 people per square kilometre. Namibia is one of the sunniest countries in the world with around 300 days of sun in a year. It has an ( semi ) arid climate which can be described as hot and dry so the evaporation is very high. Climate: Between the Kalahari in the east and the Namid Desert in the west lies the Namibian central highlands with the capital Windhoek in its centre. With an altitude of around 1700 metres and at Windhoek even 2000m there are moderate temperatures and there is an average rainfall in the rain season. These highlands keep a warm dry climate with a high humidity. The average day temperatures lie at 30° C in January to around 20° C in July and between 17° C in January and 7° C in June at night. In the winter the temperature can drop below freezing point.
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Normally no rainfall occurs between June and September. The downfall average of the last 20 years for Windhoek is 378 mm annually. 296 mm of the yearly 378 mm rain fall from January until May, 5 mm from June to September and 76 mm from October to December on average. On average, there is an annual weather cycle that you can put down as follow: During summer ( December to March ) the weather is generally hot in the whole country. Rain season starts mainly in January ( often with thundershowers ) and the vegetation will become a brown-green colour In April and May there is still a little chance of rain but the temperatures start to drop. In the winter ( June to September ) no more rain will fall and the day temperatures are moderate. The nights are cold, and in the inland and desert frost can occur. From October to November the dry season is over and the temperatures start to rise increasingly. In this period rain begin to fall again and the vegetation turns green again. 10
Summer in Namibia: You can say summer in Namibia starts between November to December and ends in March. This is also the rain season of the country. After 4-5 months of drought it’s starting to drop around December, but the season really begins in November. From September to November the precipitation has a seven-fold increase from 0-5 mm/month in September to 30-35 mm/month in November. When the rain starts to fall, the ground and vegetation will gain a lush green colour. Around the country water places will start to form, were native inhabitants can drink. Besides the precipitation, the temperature will also start to rise from a cold 5-25° C in July to a nice 15-30° C in November. This huge difference is also a reason why the ground and vegetation is turning into a green colour.
Winter in Namibia: The winter in Namibia start around April to May and ends at the end of September. The winter is the dry season in Namibia with a downfall of around 05 mm/month and temperatures between the 5° C and 25° C. With the end of the rain season most animals move to other countries, to find food and water. In the winter the desert and the savannah are very dry places, were the temperatures can drop under the -0° C because of the lack of clouds. Clouds prevent the heat to leave earth, so without clouds no heat will be kept on earth While the temperatures from winter to summer will increase in one month with 10-15° C, the temperature will decrease with only around 5° C/month. This slow decrease is very dainty for the native animals. If the temperature slowly drops the animals have the time to travel to other, warmer, countries. If the temperature would drastically drop in one month the wild animals wouldn´t have the time to move to other countries. Geography: 11
Geographically Namibia has different 3 climate zones made by two letters, each letter standing for a specific criterion. Namibia lies in the following climate zones: 1. Aw ( savannah climate with dry winters ) 2. BW ( desert climate ) 3. BS ( steppe climate )
Aw climate: In this Aw climate lies an arid zone which mean tropical deserts like the savannah plains, with inhabitants like lions and giraffes. The capital A means the temperature of the coolest month is 18 degrees Celsius or higher. The w means winter drought, only rain in the summer.
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BW climate: This BW climate lies in the Kalahari desert which is in the moderate part of the arid landscape zone, where is none too little vegetation. B stands for the dry climates were more than 70% of the annual precipitation falls in the summer, and the W stands for desert climate.
BS climate: The BS zone lies more in eastern Namibia, there lies the Miambo savannah, which is in the semi-arid zone of the Tropical landscape zone. In the Miambo savannah grows only grass and little bushes with now and then a tree. The capital S means it is a steppe climate is were less than 70% of the annual precipitation falls in the summer. ( source http://www.info-namibia.com , www.google.com , De Grote Bosatlas 53e druk http://water.epa.gov /www.britannica.com www.klimaatinfo.nl/namibie/ )
Agriculture and herding in Namibia : Namibia is a country were 5% of the national GDP ( Gross Domestic Product) consists of agriculture and herding, but 25% to 40% of Namibian inhabitants depend on subsistence agriculture and herding. Mostly the Namibian agriculture exist in two forms: - Crop farming and forestry - Livestock and meat products Crop farming and forestry. Because of the high temperatures and little rainfall farming is only possible in some parts of Namibia, less than 1% is arable. Agriculture exists out of two sectors: 1. Commercial sector The commercial sector has about 50.000 workers who are producing 80% of the annual production. 2. Subsistence sector The subsistence sector is mostly situated in the poorer areas. Namibian agriculture exists out of a three-tier system: About 4.000 commercial ranches; 20.000 stock-raising households; 120.000 mixed-farming operations. When the ranches were build, local farmers divided in about 120.000 mixed-farms only got 5% of the arable land, where the ranches took 66% of the arable soil.
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Corn is mostly grown in the area known as the Grootfontein-Otavi-Tsumeb triangle, where the smaller farms are located. But because of the high temperatures and little rainfall Namibia is dependent on South Africa for corn, sugar, fruit and vegetables. Other products produced in Namibia are mahango, cotton, groundnut, rice, sorghum and vegetables. Forestry In Namibia, forestry is a very big thing. Forestry is learning and enacting how to maintain all natural resources and wildlife in forest lands. Forestry is mainly maintaining the nature, but still win the resources man needs in a broad range of concerns. Those resources are mostly fish, timber, wildlife and plants, but also water, soil and recreation. Forestry can be carried out in a few ways: - Monitoring and supervision - Only old trees are cut down - New trees are planted - Tourists are guided and monitored - Young trees are strictly protected
Irrigation. Irrigation is a way of farming and making use of a system to provide water for crops in dry places. In 2000 Namibia had a total water consumption of 300 millio n m³, and 213 million m³ of this was used for agriculture. 136 million m³ was used for irrigation. Irrigation is only of use in selected sites along the borders of the rivers in the north and south, and in areas with a lot of groundwater and suitable soils.
On the other hand, irrigation has a negative side. When irrigating crops, ground erosion will be increased because when ground water or river water is used for irrigation it contains a lot of salt and other minerals. Because of high temperatures, a lot of water will evaporate, leaving the salt and other minerals behind causing salinization to occur.
Herding: Herding or mustering is making a group of herding animals ( sheep, goats, camels etc. ) to move from place to place to feed. Herding is done all over the world, but mostly in poorer countries, because richer countries mostly have their own meadow to feed their herd. 14
Herding a cattle is very hard. You require special skills, expertise and toughness to become a herder. You have to know the forest, recognize danger and know the best grazing spots. Still a lot of people in Namibia are herders because, next to the skills, it does not take much to herd a cattle. Because of this a lot of poorer people muster a cattle to earn money, and have food to feed their family. The disadvantage of herding is land demotion. This means the land be less fertile. Salinization is an example of land demotion, just as desertification. Desertification is what will happen if an area or landscape is over herded. If there are too many cattle’s in an area, they will irreparable eat all the vegetation leaving the land fallow. Because there is not any more vegetation, desertification will rise and also the cattle’s have a disadvantage of it, because they will have less to eat. ( source: www.wikipedia.com www.Knoema.com ) Vulnerability for desertification
Culture and politics Namibia was a colony of Germany and South Africa from 1884, until it gained independence on 21 March 1990. In 1966 the South West African People’s organisation ( SWAPO ) and the People’s Liberation Army of Namibia ( PLAN ) started a guerrilla war against South Africa. The war started with the first guerrilla attack at Omugulugwombashe in northern Namibia. The first president of independent Namibia was Sam Nujoma. In Namibia originally lived nomadic hunters, gatherers and livestock herders. The biggest ethnic group of Namibia is the Ovambo. This ‘tribe’ is around half of the population. These inhabitants spoke mainly Bantu languages like the tribes of Owambo and Herero. From the 18th and 19th centuries Nama and Afrikaans speaking livestock herders moved into southern and central Namibia. These herders came in conflict with the native inhabitants about land and other resources, but they lived without war with a trade associate. In the mid 1800s when the German settlers came to Namibia they exploited the natives and after the wars from 1904 till 1907 almost three quarters of the Herero population, and one half of the Namas were killed. 15
The Tribes of Namibia: San People ( Bushmen ); The San People tribe is the oldest tribe in Namibia. These people continue using bow and arrow for men to hunt, and the woman search for edible wild fruits, berries, roots and plants in the Kalahari desert. The San made much of the prehistoric art in Namibia. They are from the southern and eastern because this is where their forefathers came from. The San People was a nomadic tribe, roaming the country and scavenging for food. they had a territory, where they knew there was water and shelter to find like caves. This is why there are so many cave art paintings from this tribe. The Herero; This tribe is said to be the most cultural tribe in Namibia. Traditional Herero clothing is cribbed from Victorian European fashion. Tight bodices, ankle length dresses with high neck lines and long puffed sleeves. The Herero are from origin nomadic herders with their own cattle as an icon of their culture. In 1904, during the rebellion against the colonialists the Herero stood ruthless. Unfortunately, the Herero were slaughtered. Himba people: In northern Namibia live around 50.000 Himba. This tribe is semi nomadic, semi pastoral people. This tribe is distinguished from the northern Herero tribe. This tribe also live up to southern Angola and the Himba speak OtjiHimba. This language is a dialect of the Herero. Until today this tribe is still a nomadic tribe. Because of the hot climate in the northern semi arid climate of northern Namibia the boys and girls of the Himba tribe wear mostly skirt like clothing and sandals. The Damara; The Damara People speak almost the same language as the Nama people, but just with a little twist. They are darker skinned, sturdier and taller. Their believes are that their ancestors were the true blacks or the ‘pure’. The true blacks would’ve come to Namibia with the Khoisan. They are from
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Damaraland and the Skelton Coast. Now you can find the Damara all over Namibia. The Ovambo; The Ovambo tribe mainly lived north of Etosha, and the majority of the Ovambo still lives there, mostly living of the agriculture and natural resources. This tribe were the strong supporters of independence from South Africa and the first president of independent Namibia was raised in an Ovambo village.
Languages: The national language of Namibia is officially English, but most Namibians learn their ‘tribe’ language. Oshivambo ( the language of the Ovambo people ) is the mostly spoken language in the country. But the Kavango languages, Otjiherero ( the language of the Herero ) and Khoekhoe, the language of the Nama Damara tribe are also spoken in the country. ( www.our-africa.org )
Namibian gender equality: After the day of independence in 1990, Namibia had a lot of minorities for a big example woman. The woman in Namibia, especially in the rural areas are seen as less worthy with less minimum loans and having limited control over property. There are a lot of organisations and parties whose fighting for woman rights like the ‘Elimination of All Forms of Discrimination Against Woman ( CEDAW )’ and the ‘Protocol of the African Charter’. But actually in the Namibian Constitution gender equality is stated as ( quotation ): - Prohibition of gender discrimination. - The aim to ensure equal participation by woman in politics, economy and society. ( source: http://www.kas.de/upload/auslandshomepages/namibia/Women_Custom/boesl.pdf ) Flag: In the Namibian flag every colour has his own meaning and symbolize one specific thing. Yellow stands for the sunlight and the desert, blue stands for the ocean and the rain, green stands for crops and vegetation, white stands for peace and reconciliation and red for all the bloodshed in war. ( source: www.wikipedia.com )
Namibian politics The Namibian political system is a system with multiple parties where the President of Namibia not only head of state is but also head of the government. The multi-party system limit the president with two five-year terms. The government exist out of the branches:
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Executive branch Legislative branch Judicial branch
3rd president of Namibia, Hage Geingob
Executive branch. The executive branch is basically the prime minister together with his cabinet, both appointed by the president. The prime minister of Namibia is now Hage Geingob, with the biggest party still SWAPO. Legislative branch. This branch is by the Parliament, assembled two chambers. The National Assembly has 78 members all elected for a five-year term. Of these 78 people are six appointed by the president and the other 72 are elected by proportional representation, The other chamber is the National Council. 26 members which are all elected by the 13 Regional Councils. Each region can select two representatives to go to the National Council. This branch’s mainly purpose is to advise. Judicial branch. The Namibia judicial structure parallels the South African judicial structure. The Supreme Court is the highest level of the judicial body. All the judges are selected by the president when the Judicial Service Commission recommend them. ( source: www.embnamibia.at and www.wikipedia.org )
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Possible diseases caused by bad water quality. Low drinking water quality carries a lot of diseases with it, most of them are caused by drinking contaminated water. others are caused by harmful ions like fluoride. Some of the diseases are also caused by bad hygiene of sanitary. Here are the mostly common infections and diseases: -
Diarrhoea Caused by micro-organisms like bacteria, viruses and protozoans diarrhoea makes you lose both electrolytes and water. The loss of water can cause dehydration and finally death. Annually there are over 4 billion cases of diarrhoea, with around 1.8 million deaths, more than 90% are among children. Also, diarrhoea makes children more likely to get other diseases. This is the biggest public health problem directly related to water and sanitation. This disease can easily be prevented by washing hands after going to the bathroom.
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Arsenicosis People only get arsenicosis when they had a long term exposure to low concentrations of arsenic in drinking water. The effects of arsenicosis are usually noticeable when exposed to arsenic holding water between 5 to 20 years. Arsenicosis can result in skin cancer, lung cancer, bladder cancer and kidney cancer. A lot of fresh water in the world contains arsenic, because of this arsenicosis is a big problem around the world.
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Cholera Cholera is caused by the ‘Vibrio Cholerea’ ( www.wikipedia.org ) bacterium. This bacterial infection will cause diarrhoea attacks, vomiting and muscle cramps. The diarrhoea attacks will result in dehydration and finally in death. Cholera is treatable with anti-biotics because it is a bacterial infection, but a lot of people cannot afford this treatment. The risk of death is only less than 5%, but without proper treatment this will rise to almost 50%. Cholera is not only caused by poor water qualities but also with dirty sanitary and a lack of hygiene.
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Hepatitis A This viral disease will affect the liver and is not only caused by bad water qualities but also by poor sanitation hygiene. Hepatitis A is highly contagious and is not only transmitted by oral or person to person contact but also by contaminated food and water. If you are infected with this disease you will suffer from fever and diarrhoea. For Hepatitis A an vaccine in available.
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Guinea worms Guinea worms are known as Dracunculiasis, and this is an infection obtainable by drinking water containing water fleas infected with the larvae’s of the worm. These larvae’s will live in the body of the host like a parasite and about a year later the female worms will come out, mostly somewhere on the lower limbs. This will take a few weeks, but the worms rarely cause death. The female worms can grow up to 100 centimetres.
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Fluorosis Fluoride is a naturally occurring particle in groundwater which can cause serious damage to teeth. An over exposure to fluoride will cause teeth ranging from yellow to dark brown and big pits in the teeth.
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Poliomyelitis Polio is a disease where the nerves are being attacked which will cause paralysis. The disease can be spread by human to human contact, but also by eating contaminated food or water. This disease is caused by the poliovirus and can cause death if the virus reaches the brain or heart nerves. Now a days polio is not a major problem anymore because of the vaccines. There are two types of vaccines that work against the polio virus. The first is a vaccine containing a weakened polio virus so the body can build resistance, developed in 1950 by Hilary Koprowski. The second vaccine is an inactivated virus developed in 1952 by Jonas Salk.
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Typhoid fever The symptoms of typhoid vary a lot. High fever to abdominal pain, headaches and constipation and weakness. Diarrhoea and vomiting are not so common, but they these symptoms can also occur. In some cases the skin will turn a little rash with rose coloured spots. These symptoms usually start between six to thirty day after exposure. Typhoid fever is a bacterial infection caused by the ‘Salmonella typhi’ bacterium. Typhoid fever is a type of enteric fever just like ‘paratyphoid fever’. The ‘Salmonella typhi’ bacterium grows in intestines and blood. This disease is not only gain able by water but also through contaminated food. The risks of getting typhoid fever are increased by a lack of hygiene. There is a vaccine to prevent typhoid fever. This vaccine can prevent between 50% to 70% of cases and you have to retake the vaccine every 7 years minimum.
( www.unicef.org www.who.int http://www.indexmundi.com/ www.wikipedia.org www.webmd.com http://www.lenntech.com/ )
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Penduka project The Penduka project is located in Windhoek for woman from Katutura and other communities around Windhoek create a better quality of life. In Namibia woman have a low social status and because of this it is hard to find a job. This causes a lot of poverty, not only for the woman, but for the entire family. Also, in Namibia, health care is not as good as in the Netherlands so there are a lot of woman who suffer from diseases. This also increases the job finding problem. The core of the project is to create a safe place for woman through work, mutual care, support and trust. The woman of the Penduka project are crafters and create products for decoration in houses and a lot of other handy things, all hand made. There are 550 Penduka members and the woman work in their own homes. Through their work, the woman they embody their feelings and stories in to art and other crafting’s. They work with glass, fur, wood, clay, robe and much more other stuff and they create a lot of different products you can buy. The Penduka project not only makes beautiful products, they also give workshops in Namibia to tourists. In the Penduka village you can ‘grind a mahango with a big wooden pestle’ or you can listen to centuries old stories from the native tribes of Namibia. On the internet site ( see source ) the following is said about the Penduka project ( quotation ): “Penduka provides work for about 660 women, 110 of whom are on a permanent contract and 550 of whom work as a so called member; supports nearly a thousand tuberculosis patients in nineteen clinics; was founded in 1992 and is not dependent on subsidies or donors; organises exchange programmes between the Netherlands and other European countries; gives out interest free loans and helps women getting loans for their studies or to buy a house.” Partners: Without partners the Penduka project could not be realised. Because of this the Penduka project need partners so they have a lot of them. There are also a lot of partners located in the Netherlands. On the site of the Penduka project ( see source ) you can find a lot of partners: -
The Penduka Foundation Multicultural This foundation is a Dutch foundation and supports Penduka by providing advice on development and product sales to the project. Also this foundation is raising fund to finance specific project for Penduka Namibia. This is the European place for the products made by the Penduka woman.
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Moving Mountains This company is a big consumer of Penduka’s products. 21
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Centre for International Development Groningen This Centre is promoting companies in Groningen to do fair trade with the Penduka project.
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Blooms Fabricates a lot of bamboo furniture treated by Penduka woman.
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House of Design Groningen Helps designers to get on stage. The Penduka project is a member of the House of Design.
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Buro Reng Designs communication and graphic design for the Penduka project.
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Design Academy Eindhoven The Penduka project is cooperating with the ‘Mab and Humanity’ department of the Design Academy Eindhoven to create an easier life for the Pendukan woman.
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Namibia Working group te Monnickendam Promotes Penduka products and raise funds.
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Worldschool Involves young people with the international development such as the Penduka project.
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Partin Also a Dutch organisation for private initiatives if they are a public benefit organisation.
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Satu Miettinen The Finnish Savonia University for Applied Sciences in Kuopio, Finland. This university educates the Pendukan woman and organise expositions in the Netherlands and Finland.
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Eames Demetrios New York storyteller and film maker and producer of the kcymaerxthaere stories. Those stories give another view on the world. The Pendukan woman helped with those stories.
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Isandi Konsept Sells Penduka products in Norway.
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Wilde Ganzen www.wildeganzen.nl
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Ministry of Health and Social Affairs Namibia Cooperate on the tuberculosis program with the Penduka project since 1998.
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Hospitality Association of Namibia Provide tourism together with Pendukas own tourist centre for travel reservations and education.
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Namibia Craft Centre Shop for Penduka products in the centre of Windhoek.
The Penduka project also have their own web shop and a store in the Netherlands. This store is located in Groningen. ( source: www.penduka.com www.facebook.com/stichtingin2afrika/ )
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What is the composition of the water in Windhoek? Introduction; Since we do not live in Namibia nor are close to it, we needed a water sample. As shown in our reader it states that a professor in Groningen has the sample. As we contacted him it became clear that the water was not representative. This is because the water was not obtained in a right way. It was probably just a bottle filled from the lake and sent to us. We do not know what happened to it. But what is the right way to obtain a water sample? Time A sample needs to be delivered to a laboratory within 24 hour. This is for the bacteriological examination, nutrients (ammonium, nitrate, nitrite), acidity, bicarbonate and carbon dioxide. After the sample is taken for the location in question it needs to be transported in a dark box with cool conditions. Not freezing. Transportation As stated above it needs to be transported in a dark box with cool conditions. If you want a very accurate result you need sample bottles. You can get these bottles everywhere. (source: vitens.nl) Our sample If you let someone else examine your sample you need to give them information on how you took the sample and where. How many? Is it good to take multiple samples because than you can take the average of them all. If you only take one it will be less accurate. Nobody knows who took the sample but it is someone who lives in Windhoek, Namibia. It is taken from the Goreangab Reservoir after it passed through a rough sand filter to get the first impurities out. The red circle indicates where the dam is. It is probably taken from that area. We need to clean the water to make it drinkable, suitable for vegetable gardening, herbs etc. In the assignment it states “There is a reservoir available for our water supply. (Distance from water to storage is 23 metres)”
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The water is still polluted and unsafe due to microbes. We need to filter approximately 500 litres a day. It is hard to get a good visual on the situation there since everyone is too busy to help us. But on Google Maps (earth mode) we saw a lot of slums. we guessed that they urinate and poop in the water. They probably also wash themselves in it. So we can assume that there are intestinal bacteria.
After weeks of contacting companies and individual people it became clear nobody wanted to help us. Most websites are not interested in giving a tour in their lab nor wanted to examine it. At this point it is just too late to play the waiting game and we will continue. We base our starting point around assumptions from the situation over there. Luckily UV / chlorine kills most bacteria. Side note : The water sample we got was frozen for months. Also the sample was not taken the right way. Even if we examined it, it would not be 100% accurate. Our starting point will be : - Contaminated water - No life threatening bacteria for adults. - This is because you are allowed to swim in the water. And if you would die from a little bit of water you accidently swallowed nobody would be allowed to swim or come near it. - Most bacteria will die from either boiling at 100 degrees Celsius and/or die from UV-light. - There will be junk in the water. - There will be leaves, branches etcetera
Update 12-11-2015: We have lost the water sample. We got in touch with a Canadian wastewater expert and explained me techniques how to check how many bacteria are in the water. This is a DIY method or do it yourself. This does not tell you what bacteria are in it but it gives you a really good explanation how contaminated it is. Relevant bacterial tests will include coliform counts. The definition of this is: “Alternative measurements of bacteriological water quality can help you understand general fecal coliform bacteria counts and relate them to the real world. Understanding water quality can help you design and use systems better.”
Before we start we want to point out this method is not do-able anymore since one of the TOA’s had thrown our water sample away. This is pure educational for us to learn about. This is a good method to get an overview but also can be really inaccurate. Since the water is taking from a river according to Christien it is flowing water. But if there is an animal who pooped into the river. What is the level of contamination? And what if we just got a lot of bacteria in one sample but in reality that is not the case but bad luck. This is why this is an 25
estimation. This will evaluate the qualities water but does not say what or which bacteria are in it. You have a couple indicators when you do this. - General coliforms: this will indicate that the water has come in contact with animal or plant life. General coliforms are almost always present. Even in your Spa or O2 bottled water. They are not harmful at low levels. Water from perfectly sealed tubes with UV light and chlorinated water are the only types of water with zero general coliforms. If there are a lot of general coliforms this will indicate that there are is a lot of compost in it. - Fecal coliforms: this indicates that there are bird of mammal excreta in the water. - Enterococcus bacteria: this indicated that there are feces/excreta from warm blooded animal like a dog, elephant or even humans. The more closely related the animal is, the more likely we get infected. But the biggest concern are human feces. Because anything which infects a human could infect another. This method will not show that specifically and there is no method available to do this on a large scale. Although there are some super expensive genetic studies that can give a presence or absence. Contaminated water by human feces is a classic. This will rapidly spread infections. The more pathogens a human carries the worse the effect is going to be. Research by Oasisdesign shows that in the United States of America infection rates by human feces are around 5% and in areas with poor hygiene and contaminated water supplies it goes easily to 100%. A water purification plant (bio-filtration) removes bacteria and will test safe when doing this. But in reality it does not remove viruses. From here we will give an existing research and analyse it. We will also give some examples with it and some more explanation. (Source: https://en.wikipedia.org/wiki/Fecal_coliform) We will take an existing research. It is measured in buttwipes/swimming pool. We have no idea why this is and why he chose it but we have to do with it.
Human feces are the worst feces and one butt wipe is really bad. We live in the Netherlands and have a high water quality standard. That is why we are going to look at the sample 26
measurements. In chlorinated water there are 0 butt wipes / swimming pool because chlorine kills literally everything. The river in Santa Ynez is a crystal clear river located in California, USA. This contain 2500 butt wipes / swimming pool. This gives an indication of how contaminated the water is. And if we were to test it we could check this table. 3 samples before the filter it and after we filter it and check if it is safe to drink. The drinking standard we have is 1 butt wipe per swimming pool. That is 0,001 butt wipe per bottle. Additional considerations: It also heavenly depends on what feces you got. Some are worse than another. Also it depends on yourself. Some people have a much better resistance than someone else. Also the particles will sink either to the top or the bottom. If we can make a good system we have to keep this in mind. Also feces can dissolve. That takes around 16 hours. We can’t measure this. We take water from a river. The river is flowing and will distribute the fecal matter pretty evenly though the water. If the flow is enough there is less of a danger. Flow can be estimated with a calculation: Width x depth x ½ surface speed (Source: http://oasisdesign.net/water/quality/coliform.htm)
What do you need for this method: - Sterile collection container / test tube / sterile bottle / sample bottle - Sterile pipets or sterile transfer pipets - Sterile petri dish - Coliscan Easygel - Incubator set at 37 Celsius Procedure: - Label the petri dish with location, name and time of the water sample. - Wash your hands with antibacterial soap and use gloves - Use the sterile pipet or sterile transfer pipets and take between 1-5 ml of the water sample and put it into a small bottle (sterile) and add a little bit of easygel. - Shake the bottle or use one of those swirl machines. - Pour the mixture into a sterile petri dish and swirl till it is evenly covered. - Close the petri dish and wait for 40 minutes. - Incubate the plate upside down to minimize the condensation at 37 Celsius. - Count colonies 24-48 hours later. And see a pour plates guide to assist you in determining which colonies are fecal colonies. - Colonies can be analysed further with a microscope. This can be done by anyone.
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What kind of filtration methods can we use? Introduction: We will discuss different methods of filtration we can use for our water purifier. We have contacted multiple companies and people which nobody even responded to. We also contacted the websites Worldschool suggested in the assignment but after 2-3 weeks we still do not have a reply from them. This is really bad. We will search the internet to get as much information as possible.
Side note: We will only discuss methods which are achieve-able for us. Some methods we just can’t use or are too expensive. Distillation: This is the most common method. You first heat the water to boiling. When it is boiling the vapor goes up and it collected in the cooler. In the cooler there is a cold liquid that cools the vapor down and it becomes water again. This is what you see on survivals shows on TV although this is not 100% useable water. Some contaminants can be carried into the condensate and survive it like herbicide and pesticides. This is called a “carry over”. This can become concentrated in the final product. Herbicide: Herbicide is a collective noun for weed control. You got different types of this substance: - contact herbicides - growth substance herbicides - soil herbicides - systemic herbicides It is very toxic for people and plants. There are a lot of different herbicide. It is commonly used to control weeds but it has some disadvantages. It is negative for the biodiversity, wild flora and all the insects. When used on a bank it can contaminate the surface water. Pesticides: Pesticides are substances meant for attracting, seducing and destroying organisms which are considered harmful. For example they are used to kill mosquitoes that transmit deadly diseases like malaria. Insecticides can protect animals against diseases caused by mosquitos or parasites. Pesticides in humans protect the body against moldy food. Pesticides mostly used by farmers by preventing big losses in their field. A study found that using pesticides reduce crop yields by 10% which is a lot! Although there are some studies which found that using pesticides is bad for humans but there has been no direct evidence. (this is about exposing not “drinking” it) (Source: http://www.allaboutwater.org/distillation.html)
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Distillation advantages: - Removes a lot of contaminants. - Easy to use
Disadvantages: - Consumes a lot of energy. - Does not remove all the contaminants. - A lot of maintenance. - Too filter a lot of water at once you need a lot of space. Conclusion: We don’t think this is a good method for Penduka. It requires a lot of energy and doesn’t filter all the contaminants away. Even if we could use solar energy, solar systems cost a lot of money we do not have. Although is it very easy to use and maybe if we find a clever method to boil the water we can use it. Reverse osmosis: Reverse osmosis or RO is also a very common method to purify water. It removes 90-99% contaminants depending on the membrane. It is basically a pump with high pressure which pushes it though the membrane. Those membranes are capable of filtering practically all the particles, organics and even bacteria. Reverse osmosis is a technology which is used by the most leading water bottling companies. Natural osmosis is caused when two different concentrations are separated by a semi permeable membrane. It works a little bit different with reverse osmosis. Now there is a pressure pump which pushes the water though the membrane. The water dilutes the more concentrated solution and the end result is balanced. This method is super effective in removing several impurities from contaminated water. For example solids (dissolved), asbestos, toxic metals, radium and chlorinated pesticides. According to multiple websites and studies this method is highly effective combined with activated carbon filtration. Conclusion: This is a very good method of purifying water. Although this method is not cheap. As you see on the image on the right this is an installation. Even with the smallest reverse osmosis systems you still need some heavy equipment.
(Source: http://www.freedrinkingwater.com/water-education/qualitywater-filtration-method-page3.htm )
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Activated carbon filtration: Activated carbon filtration is using the activated carbon to filter out contaminants and impurities. It is basically a block filled with activated carbon and water is pushed through it. Although there is not a lot of pressure since if it goes slow though the filter it is exposed longer to the carbon. Is it using the chemical process of absorption. This is the process whereby contaminants in the fluid are trapped inside the carbon. This is why it is used not only in water purification but also in air purifiers and even in respirator masks. Activated carbon is the most effective in removing sediment, chlorine (which is really nice), VOC and taste. They are not good at removing salt, minerals and non-organic compounds (dissolved). Fun fact: Carbon filters have been used for hundreds of years already. There is evidence that they have been used in ancient Egyptian cultures. Advantages: - Removes dissolved organics and chloride effectively. - Easy to use - Has a long life Disadvantages: - It generates carbon fines - It does not remove salt, minerals and non-organic compounds Conclusion: This is a good method. It is cheap; you don’t need expensive equipment; you can combine it with other equipment etcetera. We can use this combined with chlorine at first since that kills most bacteria. And since carbon is really good in removing chlorine it would be pretty cool. Although we need to test that. Although carbon filters can generate carbon fines (small particles which are grey/black). This is when new carbon filters are placed. This is why all the filters should be generously flushed with a couple gallons of water. This will wash away the carbon fines and make the filter ready to use. This is just to keep in mind. Side note: Chlorine is a chemical often used in swimming pools to kill bacteria. If you pour chlorine into water it breaks down into different chemicals. Like hypochlorous acid (HOCI) and hypochlorite ion (OC-). They both kill microorganisms and bacteria by attacking the lipids in the cell walls and destroying the enzymes and structures inside the cell. This works the best if the pH is between 7-8 and 7,4 is ideal.) Ultraviolet Radiation (UV): Ultraviolet is a type of energy in the electromagnetic spectrum. It is lying between x-rays and visible light. UV dangerous to be exposed to. We cannot see UV light or rays but we are exposed to them every time we step into the sun. When you get a sunburn, UV light is responsible for causing it. But the reason why we can step into the sun and don’t get instant skin cancer is because we have an ozone layer. When being near an UV lamp the ozone does not protect you since it is not near you. This is why you need to have the UV lamp in a closed section of your water purification system. You can also use glass since glass blocks the UV 30
rays. But to be 100% safe most people recommend using UV in a closed section. Ultraviolet systems use special lamps or bulbs that emit UV light of a particular wavelength. They generate around 185 nm or 254 nm (when used for water purification). Ultraviolet attacks the genetic core of a microorganism and rearranges the RNA/DNA. When this happens the microorganism loses the ability to function and reproduce. This is why the process is really effective and destroying around 99,99% of the harmful microorganisms without adding any chemicals. (under ideal conditions) The quality of the end product depends on a couple factors. The UV needs to have appropriate contact with the water. The UV bulb also needs to have the correct size. With a larger tank you need to get a lager bulb. It is also really important to have a good pre-filter. Otherwise the solid particles block the UV to kill microorganisms. The microorganisms use it as a shield. The quality also depends on more factors. Like the flowrate. If the flowrate is too fast, the water will not be exposed long enough to kill all the bacteria. It needs to have proper UV exposure to work. If the water flow is slow it can damage the UV lamp. If it is too slow the water will heat up too much damaging the UV lamp. That is why when using an UV lamp it needs to have a flow. Although this is really good, it had some disadvantages over other methods. UV rays or units only kill bacteria at one point in a water purification system. They do not provide a long time disinfection effect like chlorine does. If only one bacterium passes though at one point, there is nothing you can do. This is why you need an excellent piping system. Also the bacteria cells are not removed in a UV unit but are converted into pyrogens (particles which can give you fever when getting injected). Those are the main food source for bacteria which survive it. Due to these limitations, again, you need to have an excellent pipe system and needs to be periodically sanitized with a chemical disinfectant.
(Source: https://www.espwaterproducts.com/uv-water-purification/ )
You also need to replace UV lamps. This is because they do not burn out as normal lamps. Instead, UV lamps will solarize, reducing their intensity to about 60% of a new lamp after only one year of continuous use (~8760 hours). If use a new lamp it will generate a dosage of 60000 uW-s/cm2. When the dosage drops to 50-60 % you should replace it. Ot it won't effectively kill all the bacteria. The lamp life will also be shortened if you often turn it on or off. Since a lot of water passes though the tube you should periodically clean the lamp. It will be covered in debris. If you don’t do this the UV will not kill the bacteria. You also need to monitor the UV dosage. You can do this will an UV light intensity meter. This indicated the
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penetration of UV light. If there is a low intensity you should replace the lamp for proper disinfection. Advantages: - Effectively removes most bacteria. - Easy to use. Disadvantages: - Will not remove small solid particles. - Careful maintenance. - Does not protect the water after the UV light exposure. - You need electricity (not really a con but worth mentioning in an area like Penduca) - Proper pipe system
Conclusion: UV radiation is a good method to remove bacteria. This is fairly easy to setup and it doesn’t require any technical skill to maintain it. Although you need to be really careful with this. We will need to think of a proper piping system. And an easy method to test the water if it is safe to drink. If only one bacterium survives it you can throw away all the water. If we combine this with a bio-filter this will work out. But a proper piping system is really expensive and not an viable option. ( Source : https://nl.wikipedia.org/wiki/Actieve_kool http://www.watertreatmentguide.com/activated_carbon_filtration.htm ) Update 15-12-2015 We chose for a different approach after we learned more about purifying water. UV is more expensive and requires more maintaince. We also don’t know if there is electricity (or enough) to power an UV light. These are all methods to kill bacteria. But we need a rough filter as well to filter out rough material. Like small leafs and contaminants that can be filtered out by a method we are going to talk about below. We need material that is durable and cheap. It also needs to be easy to be maintained. Our filter will consist out of a tube filled with different materials. Those will filter out a bacteria and solid parts. We want to use the down force of the hill since the water goes down according to Christien from Penduka. This will ensure we don’t need a pump to power the water stream which is good. When it arrives at the top (it goes from top to bottom, but we build it from the bottom to the top) of the filter it will first go through gravel or rocks to filter really, really big solid parts. We can use any kind of gravel there is available. Gravel is not expensive and can be free in most cases. Than it goes through fine gravel. This is to filter out smaller parts but which are still rough. Just to be sure and since it can be easily done why not? Just smash gravel to smaller pieces.
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The 3rd layer needs to be some sort of coarse sand. Most people will know this as aquarium sand and is mostly 1x1. This can be easily obtained in a river or buy it at any store. It is not that expensive. The 4th layer consists out of fine sand that is also easily obtainable. This will filter out the small impurities of the solid parts. This sand needs to be really fine. So not all sand will qualify for this one. The 5th layer we will use activated carbon or charcoal. This will kill some bacteria but not all of them and since we do not know what is inside it we need to kill the bacteria with something else. Of course from the methods we discussed above. Professional help 12-11-2015 : I searched help on a popular forum called “Reddit” or “The frontpage of the internet”. We asked help on the subreddit called wastewater. (www.reddit.com/r/wastewater) and made a thread. This is help for the methods we suggested and made above so maybe there are some slight changes. “Safe drink water for Windhoek Hello! I am doing a project about safe drinking water for Windhoek (Namibia) and we need to come up with a cheap efficient water solution. We did a lot of research already. We were thinking about a big (standard) water purification method with sand, charchoal etc. But charchaol does not filter out enough bacteria. Any idea how to test the amount of bacteria? And is there any other method to kill bacteria without adding harmfull chemicals like chlorine? We were thinking about an UV light but is that a good idea? Thanks a lot! “ A user called W45PN35T made a large comment full of useful information. He is wastewater expert located in Canada. He recommended slow sand filters.
Fun fact: Slow sand filters may sound weird but they are used on a large scale! For example London’s water supply is actually refined by slow sand filters! He recommended it because this can be used on much larger scale and is really easy to use. We will discuss slow sand filters and give a brief explanation how it works.
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Slow sand filters Slow sand filters are used in water purification and are used for “raw” or contaminated water. There are used to make a so called potable product. That means that it is safe enough to drink and cook with. They are usually 1+ meters deep and are primarily used to treat surface water. Slow sand filters work different than other filtration methods. There work by using a complex biological film that grows naturally on the surface of the sand. The sand doesn’t really do anything except letting the water go through slowly. It acts as a substrate. Biofilm definition: A biofilm is any group of microorganisms in which cells stick to each other on a surface. These adherent cells are frequently embedded within self-produced matrix. Biofilm extracellular polymeric substance which is also referred to as slime. Biofilm can form on living or non-living surfaces and can prevalent in natural, industrial and hospital saetings. Source: https://en.wikipedia.org/wiki/Biofilm The biofilm is formed in the first 10 – 20 days of operation. Biofilm is also called the hypogeal layer or schmutzdecke and is located in the top few millimetres of the fine sand layer. It consists out of bacteria, protozoa, fungi, rotifera and a range of aquatic insect larvae. The surface biofilm will provide an excellent water purification process. The sand will slow down the water and particles are trapped. But you need to maintain a slow sand filter. They lose performance over time as the biofilm thickens. It than reduces the rate of flow through the filter. And after a while you need to change it. There are two common methods to do this. - Method 1 Scrape off the top few millimetres of fine sand. This will expose a new layer of clean fine sand. Water is than put back into it and needs to loop a few hours through it to create a new biofilm. When there is a new biofilm you can fill the tank up again and get it back into service. - Method 2 Let the tank go half empty and wait a little bit and stir the sand. This method is called wet harrowing. This means that the sand is gently agitated. This will result in to causing partial break-up of the biological surface. This is the easiest way to clean a slow sand filter. You cannot just pour in contaminated water and hope it will come out clean. There are some really important things you need to keep in mind. We will not discuss things we cannot build or measure. Those are small details and are meant for extremely professional water purification slow sand filters like in London. Sand: When building a slow sand filter you need the right sand. The best you can get is 0,15mm sand solids. This will let the water go through but in a good flow. You can get away with play sand or just bagged sand you buy at your local shop (Karwei, Fixet etc). But having the sand is not enough. You need to clean it with preferably clean water. The sand depth and diameter is also very important. A small filter will not remove much contamination. This is why when you make a DIY or do it yourself filter you need a big barrel. Do not forget that when you put sand and water in a barrel it will be extremely heavy.
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Container: As said above you need a wide diameter. Otherwise there will not be enough purification. Because if you decrease the diameter, the flow rate must also be decreased. When obtaining a barrel you need to make lines with a sand paper in horizontal or random lines but not vertical. Otherwise water can slip through. Flow rate: You need a slow water flow to maintain good purification. The slower the better. This is why you better have a huge storage because this is not something you put on and off like an UV bulb. There are two types or ways of flow rate. One is by using numbers to indicate how fast the water moves through the sand. The other one is how much volume of water flows out the filter in a given amount of time. For a 55 gallon or 65 gallon barrel (1 gallon is 3,7854 liters) 0,15 is the effective sand size. And of course the longer water goes through the bigger the schmutzdecke gets and the slower the water goes through. Turbidity: Water that is muddy, cloudy or has a lot of solid particles in it will clog the filter within days. This is why you need a pre-filter which we already discussed above and we will use that. Recirculation: This does not apply for the situation because there is enough water in every season. But water must run through the barrel continuously. Otherwise you need to start over with it. Temperature: These filter will not work if they are frozen. Luckily the temperature in Windhoek is pretty high so it’s fine. Sand: When putting one of these filters together put water in the barrel first and then add the sand. Otherwise you get air bubbles. This will prevent air bubbles from forming in the sand. Always keep the sand wet. Location: First get to the location before doing anything because water + sand is extremely heavy. Be sure to place the filter somewhere it is secure. The supports must be able to handle at least 2000 pounds safely. Moving the filter will disrupt the sand and cause the filter stop functioning. (Source: http://www.enlight-inc.com/blog/?p=2139 ) (Source: http://oasisdesign.net/water/treatment/slowsandfilter.htm ) “ Know the basic reasons these filters work: A slow sand filter works 3 ways: Biological action, Physical straining, and adsorption. Biological (action) predation: All water, with the exception of medically sterilized water, and distilled water, has microscopic life in it. These microbes will grow in the slow sand filter if they are kept under water and oxygen and food are available. There is a mini-ecosystem that lives in these filters. This system results in the formation of a biological film, called a Schmutzedecke (German for dirt blanket) on top of the sand and to a lesser amount, further down in the sand. Disease causing bacteria, and viruses (bad bugs) are literally eaten by this collection of microbes in the filter. All that is left is harmless minerals. Most, if not all, of the small number of bad bugs that happen to slip by the schmutzedecke will die off as they move further down in the sand layer due to lack of available nutrients. Physical straining: Particulate matter is strained out by the sand and the biofilm on the top of the sand.
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Adsorption: This is a fancy way of saying that the sand grains actually can attract small particles and cause them to stick to individual grains of sand. This is similar to but, not exactly like , the way water actually sticks to itself due to cohesion and adhesion. “ ( Source: http://www.enlight-inc.com/blog/?p=2139 )
Overall conclusion: After all the research we have done about filtration we need to make a system. We need a pre-filter and a slow sand filter since that is the cheapest solution. The assignment said it should filter around 500 litres a day but that depends on the size of the slow sand filter. We will make a small one on scale otherwise we can’t move it. In the next section we will show our progress upon making one.
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The water purification system design - Pre-filter Introduction: Before building a purification system we need a plan. This is about how we combine all the different components and how we make this work. The system needs have a couple important elements. - Cheap. Not only the build needs to be cheap, to maintain it as well. - Easy to use for everyone - Work in a hot environment. What will we be using? We have choice of a wide variety of filtration methods. To start we need a rough pre filter. This will contain different materials to filter out the rough stuff. Pre Filter The pre filter will be located on the hill near the slow sand filter. For the demonstration we will be using a “ghetto filter”. This is the cheaper version of the final version. The final version will contain higher quality plastic. And materials which will last longer. Also in the sun. What we are designing at the moment is for pure demonstration. The real one will look way more professional and does not use most of the things in here. We will make a separate plan for the real filter. Although it is quite similar to this one. What do we need to make a rough pre filter? A plastic bottle with a cap on it. A hammer and a nail or a drill with a small bit. A piece of cloth or a coffee filter A big glass or something else to put the bottle into (it is upside down) Sand, size doesn’t really matter at the pre filter. Gravel, not too big A container or a pipe to the next stage which for us is a slow sand filter. A craft knife
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Step 0 Cleaning the bottle Before doing anything you should clean the bottle. You should also use soap and clean it out with a lot of water. This is because some sugars or other chemicals are still in the bottle. You can get rid of the glue on the outside with a little bit of turpentine. Gloves are optional but safe. Clean the bottle with soap after using turpentine!
Step 1 Cutting the bottle We will be cutting open a plastic bottle. Probably a large Coca Cola or something similar to it. We cut the bottom off to get inside the bottle. we cut it open with a craft knife. It should be around 2-3 centimetres from the bottom. Save it because we might need it again. You should also strip the bottle and clean it very well.
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Step 2 Make a hole in the cap Use the hammer with a nail to punch a hole in the cap. We will make it slightly bigger because it goes to the next stage. You should be careful with this and put a piece of wood underneath it.
A small edge After using drilling or smashing a hole in the cap. You will see a small edge appear around the circle. This can stop the water from going in properly so you should get rid of it.
Using a sander We used a sander to get rid of the edge. You can also use other tools but this is the most convenient. It is a small sander with switchable types of sanders. We also made the hole a little bit bigger. Do not forget to wear safety glasses, and if you decide to put it in a vise like me don’t fasten it too much!
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Step 3 Cap filter After we punched a hole in the cap with the put a piece of cloth or coffee filter in the cap and screw the cap back on again. The cloth or coffee filter should be sticking out. If the cap doesn’t go on, use a less thick piece of cloth.
Type of cloth We took an old shirt and cut a little bit off. This was cotton. Don’t get something which is too thick. And also don’t cut too much. You only need a little bit. (10x10 +-)
Screw it on Put the cloth over the cap and screw it in. Make sure the cotton is tense on the inside. Otherwise you might not have covered all the areas in the cap. Screwing should be no problem. If it is, get another cap.
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Step 4 Put it in a glass After this is done we put the bottle in a glass. You can also use a vise or something like that. If you decide to put it in a vise, don’t fasten it too much!
Step 5 Adding charcoal For this you want to wear gloves. You want to fill the first layer with activated charcoal. They most likely come in large pieces. A good way to make it smaller is to put it in a towel and smack it on a hard object. You can also use the hammer to punch it into smaller pieces. A small reminder, the towel is going to be covered in charcoal. So you might want to use an old towel. If you smashed the charcoal into smaller pieces (not too small of course) you should fill the bottle with 1/4 or 1/3 charcoal. The charcoal you see on the right it the one we used. It was small already. With one hand We kept the sack and with the other one (with a glove) we gently filled the bottle. Update 15-12-2015. You should wash the charcoal first! We did not do it and the filter is stuck now.
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Charcoal When doing this make sure you wear at least one glove.
Step 6 The sand layer Fill the next layer with sand. We will be using sand from the river (de Lek) in Lexmond. We did clean the sand a couple times because it was very dirty. This should be around the same amount as the charcoal. The best is using different types of sand sizes. For example fine grained sand and a coarse grained sand. This way the water goes through multiple layers and will help to make it cleaner.
Cleaning the sand 42
Put the sand in a bowl and start filling it with clean water. Stir a bit and the filth will come off. The sand was way dirtier than we thought. Proceed to carefully empty the water and refill it again.
The result After cleaning the sand you should see something like this. Empty the left over water. This sand is clean now!
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Make the next layer Carefully put the sand from the bowl into the filter. Make sure you put something like Glass under it because the sand is still wet. Some water will go through the filter already. Make this about 1/3 or 1/4 of the bottle. When finished try to put pressure on the sand with your hand to straighten it out. Step 7 Gravel The rest should be gravel. Don’t fill it to the top. We will use gravel from my garden. It is better to use multiple layers of gravels with different sizes. This is mostly for filtering big solid pieces from it. Multiple layers equals better water quality.
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Cleaning the gravel This works the exact same way as cleaning sand. From it outside it looks quite clean but it is actually really dirty. Always clean your materials first before using. Above a before and after shot of the gravel.
Gravel time Put the gravel inside the bottle. We started with the small stones and ended with the larger ones. Put them in carefully and don’t fill it to the top. You still need some space for water!
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Final For our presentation we will be hanging it on a tripod or something else. This is the best for a demonstration. It will be above the slow sand filter. This is all on scale and we need to find out how much this filters per time unit. Of course this does not filter 500 litres a day. But when you use a big barrel and fill it with sand it should be good. We will calculate how big it should be. We had put some water in it to test it out and it worked! Next project is to make a slow sand filter! This is only the pre filter. (Source: www.Wikihow.com / http://www.instructables.com/id/Simple-Water-Filterout-of-a-Waterbottle/ / http://www.wilderness-survival-skills.com/how-to-make-awater-filter.html )
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The water purification system design - Slow sand filter How do we do it? First of all, we are going to build a scaled down version. This is because there needs to be flowing water otherwise the schutzdecke cannot develop. This is fine when you build a scale model of the “final model”. But imagine a barrel filled with water and sand, which will weigh a ton. And we need to transport it as well. What we wanted to do is take a small water tank and use that. But we need to make holes on the side (near the bottom) so a bucket is more useful. But if you have experience making something water-proof, that is really hard. But we have no other option. We will make one hole and connect that to a small pvc pipe or something similar. The gravity will push the water down through the water and clean it. This will be pretty hard. We gathered the stuff we need and started working. Step 1 Acquire the materials You can use multiple materials for a slow sand filter. But this is what we used. - A plastic box, you can also use a barrel or a bucket. A larger bucket can filter more. My box is not that big / high. But we will use it for demonstration. This is because a large barrel filled with water and sand is extremely heavy. - PVC pipe. We got a 1.5 meter pipe. If you have a larger barrel or diameter you want to adjust that. - Connectors. You will need these for the pvc pipe. My initial thought was to make it an n shape. The blue pieces are connectors, red is the pipe.
- Sand. Depends on the barrel you use how much. Sand does not cost a lot and you are forced to buy big bags of sand anyway. - Drill, is very handy to use but optional. - Marker or something else to mark certain distances, - Tape-measure to measure distances
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Step 2 measuring your materials Measure first before doing anything! The golden rule is “measure twice, cut once”. We have a very large diameter so we want to spread the pipe across the box. This way we get the most water out of it.
Step 3 Cut the pipe After marking it with a marker or leaving a small cut. Proceed to cut the pipe. We used a handsaw because it was late already. Cutting straight with a handsaw requires more than just 5 senses. Unfortunately We did not have the 6th sense and cut it a little bit oblique. It is way easier with an automatic saw. Be sure to fasten it. If it is too loose like mine you end up with a small deviation to the right.
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Step 4 Scrub your pipe When you are done cutting it. You should carefully scrub it with sandpaper or a sander. We used sandpaper (coarse) and it went great. Using a sander might be a little bit of an overkill. Be sure to rough up the edges a bit for the glue. Scrub the inside and the outside.
Step 5 Cut a hole in the box and assemble This step was done with help of my neighbour. He drilled a hole in the box with a drill. This should be done carefully otherwise the plastic will break. Although you won’t have this problem if you use a big barrel. In our first attempt the plastic broke because of vibration. This is why we now used a piece of wood behind it to minimize the vibrations. We put a coupler between it so it won’t leak.
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The holes are on the bottom side of the tube to keep the sand to a minimum. There is a panty on it to keep the sand out even more. It is a bit loose at the moment but we will fasten this with cable ties.
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The inside is roughed up. Don’t forget this step because otherwise contaminated water will go down on the sides. Just do it in all directions and it will be fine.
Because of the water pressure it will try to find a way out. So with the pressure the water will start going up and with another bend it will go to a reservoir. We have not yet assembled it for the simple reason that we first need to make the biofilm. This is a long process and will start it around 2 weeks before the presentation.
This is not on scale 1 : This will make the biofilm. This way you don’t have to add water constantly and don’t have to monitor it. The water needs to flow and that is the reason this is the best option. Unfortunately this won’t work without a small motor. That is why we will get one or do it like normal and refill it. 2 : This is the final product with the pre- filter on top. It will lead to a reservoir (sealed not like in the picture) and is safe to drink. It is extra safe to add a little bit of chlorine to kill 52
bacteria that might occur but we don’t think this is necessary. 1 teaspoon of chlorine will disinfect 3,8 litres. Although you can add a little bit less because it is already purified.
We will attach a small motor on the top to push the water through it. If that is too much trouble we will just do it manually and re-use the filtered water.
This is the final product. We know the water is coming from a pre-filter over there. There are two options to get water in the filter. Do it manually or by installing a long PVC pipe to a separate barrel higher than the filter barrel. That way the water will go into the barrel and you can open up the tank and water will flow. Keep in mind that it needs to be a slow flow!
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When we are a week prior to the presentation we will start the filter up. The first layer is a gravel layer. It should cover the tube. Then add clean sand with water to remove air bubbles and let the filter do its work. The biofilm should start building up. We don’t do it now because water + gravel + sand is extremely heavy and requires maintenance. Of course Penduka should take a bigger barrel but once set you can’t move them! Moving a filter is bad and really heavy.
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Conclusion During this project we have experienced positive and negative experiences. We have learnt a lot from this project but faced some difficulties. Overall we are happy we have experienced the World School project and we are grateful that our school gave us the opportunity to do this. What we have learnt: We have learnt about the climate of Namibia. For example the differences in temperature and landscape between Namibia and the Netherlands. We have learnt about the culture of Namibia. Also we have learnt about the culture and politics. We did not know Namibia was a colony of Germany. Also the number of inhabitants was much lower than expected. We have learnt a lot about waterborne diseases and the effects of them. We have tried and examined many different ways of purifying water. We have made a working system to purify water in a cheap way. We also learnt a lot from building it. After investigating in the different ways of water purification we came to a conclusion that a slow sand filter, in combination with a pre-filter is the best way of purifying water in this situation. We chose for this option because it is cheap, good working, and not too difficult. The only thing that needs to be adjusted is the size of the barrel and the corresponding tube. And that is the beauty of it. It’s super simple!
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Important mail. Only these people have responded and/or was worth putting in. We did not record any phone calls. dag Sam, een tip: mail niet alleen, bel! veel bedrijven/ overwerkte medewerkers worden gek van de honderden mails die ze krijgen ... waarschijnlijk kom je al snel in de spam. bel, stel je voor, beschrijf wat je zoekt, maak dan de afspraak om per mail meer info te geven, of bezoek ze ... vriendelijke groet, Frits From: sam vruggink Sent: Monday, October 05, 2015 12:41 PM To: sibers Subject: RE: Water sample Hallo, Wij gaan morgen naar de TU Delft en kijken wat daar uit komt. Harstikke bedankt voor uw hulp. Mocht Vitens niet meer reageren mail ik u even om te vragen voor een ander bedrijf. mvg Sam Vruggink From:
[email protected] To:
[email protected] Subject: Re: Water sample Date: Mon, 5 Oct 2015 10:56:34 +0200 dag Sam, vergeet niet ook naar de diverse ‘beta-steunpunten’ van de TU’s en de U’s (zoals de WU) te mailen/ bellen, ze zijn bedoeld om profielwerkstuk-leerlingen te ondersteunen. van Erik Vos van Worldschool begreep ik verder dat er deze week allerlei studiedagen zijn: gaan jullie daar ook heen? zelf heb ik goede ervaringen met waterbedrijven/ waterschappen qua toegankelijkheid. met vriendelijke groet, Frits Sibers
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From: sam vruggink Sent: Monday, October 05, 2015 7:42 AM To: sibers Subject: Re: Water sample Hallo, Hartstikke bedankt. Ik heb al tientallen bedrijven gemaild voor hulp maar of ze willen het niet of ze reageren niet. Vitens wilde ons helpen maar hoor ik nu niks meer van dus daar moet ik ook achterna. Die link die u stuurde zal ik ook even contacteren. Het is lastiger dan gedacht om hulp te krijgen van bedrijven. Mvg Sam Verzonden vanaf mijn Huawei mobiele telefoon -------- Oorspronkelijk bericht -------Onderwerp: Re: Water sample Van: sibers Aan: sam vruggink Cc:
dag Sam, nog even een nagekomen bericht, Alterra Wageningen zou ook de moeite waardb kunnen zijn voor jullie onderzoek(opzet), zie b.v.: Alterra Wageningen : http://www.wageningenur.nl/nl/ExpertisesDienstverlening/Onderzoeksinstituten/Alterra/Faciliteiten-Producten/LaboratoriaEnvironmental-Sciences-Group/Laboratorium-voor-Aquatische-ecologie.htm vriendelijke groet, Frits Sibers From: sam vruggink Sent: Tuesday, September 01, 2015 8:10 PM To: sibers Subject: RE: Water sample Hallo meneer Sibers, We willen het ook zelf gaan onderzoeken maar ik bedoelde dat er hulp bij is van professionals. Ook had ik een vraag over het afnemen van water. Ik kan nergens op het internet vinden hoe je dat op een goede manier afneemt. Kunt u mij daar iets over vertellen of 57
een artikel / boek naam sturen via de mail. Onze TOA's op school wisten het ook niet, en sinds ik geen email adressen heb van andere professoren vraag ik het maar aan u. Water afname voor onderzoek moet op een bepaalde manier maar ik kan nergens vinden hoe. Ook al vind ik dat weet ik niet hoe het een afstand van Namibia naar Nederland zou moeten gaan zonder het in te vriezen. Want het lijkt mij dat er veel bacterien/organismen dood gaan tijdens dat proces. Kunt u hier iets over vertellen of misschien een email adres van een collega die ons wil helpen. Echt hartstikke bedankt voor alles! Mvg Sam Vruggink From:
[email protected] To:
[email protected] Subject: Re: Water sample Date: Mon, 31 Aug 2015 17:43:38 +0200 veel plezier er mee .... zelf onderzoeken is leuker dan laten onderzoeken....misschien kunnen jullie ergens aan de slag met goed uitgeruste labs ( microbiologisch/ chemisch ...)? vriendelijke groet, Frits Sibers From: sam vruggink Sent: Monday, August 31, 2015 4:36 PM To: sibers Subject: RE: Water sample Dag meneer Sibers, Hartstikke bedankt en dat zullen we zeker doen. Ik ben al opzoek naar een laboratorium zodat ik het met mijn partner professioneel kan laten onderzoeken. Mvg Sam Vruggink From:
[email protected] To:
[email protected] CC:
[email protected];
[email protected] Subject: Re: Water sample Date: Mon, 31 Aug 2015 16:15:06 +0200 dag Sam, het monstertje is verstuurd naar de eksterlaan, komt denk ik morgen aan ( via DHL); 58
BELANGRIJK!! werk met handschoenen, was je handen met ontsmettingszeep e.d. als je met dit water gaat werken, je weet immers niet waarmee dit oppervlakte water is besmet LET OP!!! het flesje was diepgevroren, de envelop werd echter wat vochtig ( condens?lekje?) ik hoop dat een en ander goed overkomt veel succes, met vriendelijke groet, Frits Sibers opm. het is maar een klein monster, dit betekent dus ook, dat als je iets niet meet, dat dit dan ook overeenkomt met de werkelijkheid ..... From: sam vruggink Sent: Monday, August 31, 2015 1:29 PM To: sibers Subject: Re: Water sample Eksterlaan 48 4143AC Leerdam Op naam Sam Vruggink worldschool Dat is het school adres. Hartstikke bedankt voor alle moeite! Mvg Sam Vruggink Verzonden vanaf mijn Huawei mobiele telefoon -------- Oorspronkelijk bericht -------Onderwerp: Re: Water sample Van: sibers Aan: sam vruggink Cc: dag Sam, een adres zou dan wel handig zijn .... ik weet niet of dit vandaag nog gaat lukken, daar ik zoals gezegd morgen in de vroegte vertrek. eventueel gat het lukken via dhl met vriendelijke groet, Frits Sibers
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From: sam vruggink Sent: Monday, August 31, 2015 9:54 AM To: sibers Subject: RE: Water sample Hallo, Misschien een rare vraag maar kan het op de post? Of kan dat niet i.v.b dat het ingevroren is. Als ik dat namelijk heb kan ik universiteiten benaderen om het samen met ons te onderzoeken. Ophalen zou eventueel kunnen maar word wel een gedoe, maar het kan in principe wel als het niet op de post kan. Ik wil het zo snel mogelijk hebben omdat we niet zoveel tijd hebben i.v.b onderzoeken, prototypes etc. Mvg Sam Vruggink
From:
[email protected] To:
[email protected] CC:
[email protected];
[email protected] Subject: Re: Water sample Date: Sun, 30 Aug 2015 15:50:44 +0200 dag Sam, Jullie zouden het volgende kunnen doen: a. als ik begin oktober weer terug ben, kunnen we afspreken hoe we het watermonstertje bij jullie zouden kunnen krijgen; dan is het misschien mogelijk om een kwalitatieve indruk te krijgen van een aantal relevante abiotische en biotische factoren van dat meegebrachte monster; welke dat zouden kunnen zijn, en hoe je iets dergelijks bepaald ( geavanceerd gebruik makend van een professioneel lab, minder geavanceerd, gebruik makend van de mogelijkheden van een schoollab, dan wel middels in het veld bruikbare methoden die ook ter plekke in Namibie uitgevoerd zouden kunnen worden ( kunnen de benodigdheden + instructie(filmpjes/ youtube?) opgestuurd/ meegenomen worden om ter plekke de bepalingen te doen?,; leve het internet!). De waarden die eventueel te meten zijn in het meegebrachte watermonster zijn niet ‘zwaar’/ betrouwbaar genoeg om daarop een aantal beslissingen te baseren denk ik, maar het geeft misschien wel iets aan. b. uitzoeken welke effectieve, goedkope, makkelijk te onderhouden, enz. zuiveringsmethoden er zijn m.b.t. microben, giftige stoffen zoals zware metalen, koolwaterstofverbindingen enz. die bovendien een voldoende capaciteit hebben c. nabouwen van een prototype ( welke dat is wordt na een gedegen voorstudie bepaald) waarmee een gestandaardiseerde testserie gedaan kan worden m.b.t. zuiveringseigenschappen t.a.v. diverse mogelijke typen vervuiling. En zijn er verwante voorbeeldprojecten waar iets van geleerd kan worden? 60
d. zoals gezegd een gedetailleerd beeld krijgen van de ‘probleemsituatie’ ( kaarten, vervuilingsbronnen, neerslaghoeveelheden, periodes van droogte, mogelijkheden wateropslag gezuiverd water, hellingshoeken, google maps, enz. ) met vriendelijke groet, Frits Sibers
opmerking: zoek deskundigheid en ondersteuning daar waar die is: vervolgopleidingen, waterlaboratoria, e.d. opmerking: houd altijd rekening met het feit dat het probleem zich afspeelt in Namibie en niet in Wieringerwerf , de mogelijkheden aldaar lijken niet op de mogelijkheen hier ... opmerking; hoe je van sterk vervuild water weer bruikbaar water kan maken is een wereldwijd, steeds groter wordend vraagstuk, ik hoop, dat jullie met slimme oplossingen komen!! From: sam vruggink Sent: Sunday, August 30, 2015 11:01 AM To: sibers Subject: Re: Water sample Hallo, Hartelijk bedankt voor de snelle email. Super informatief! Aangezien de waarde zijn veranderd moeten we er van uitgaan dat het vooral darmbacteriën / vuilnes en mogelijke middelen die ze daar gebruiken? Of is het beter dat we het monster onderzoeken en die waarde gebruiken? Wij zitten op het Heerenlanden Leerdam. Ver van Groningen af. :( Mvg Sam Vruggink Verzonden vanaf mijn Huawei mobiele telefoon -------- Oorspronkelijk bericht -------Onderwerp: Re: Water sample Van: sibers Aan: sam vruggink Cc: Koviljka Pajcin ,Erik Vos dag Sam, Fijn dat jullie voor de organisatie van Christien Toxopeus aan het werk willen! Ik kan jullie niet vertellen wat er in het watermonster zit: ik kreeg enige 61
tijd geleden een meegenomen watermonster in een plastic fles. Ik heb dit ingevroren. Hier moeten een paar kritische kanttekeningen en opmerkingen bij geplaats worden. a. als je een te onderzoeken watermonster neemt van een bepaalde plek, dan moet je daar allerlei ( wetenschappelijk gefundeerde) protocollen bij volgen, dat is hier denk ik niet gebeurd. b. het water is neem ik aan ook niet gekoeld meegenomen: o.a. allerlei biotische waarden zijn daardoor tijdens het transport veranderd, zoals zuurstofwaarden, gehalte aan bacteriën, e.d. Maar naar wat ik begrijp uit de omschrijving van de lokale omstandigheden en de mogelijke vervuilingsbronnen van het te gebruiken water mag je er van uit gaan, dat er met name sprake kan zijn van een bacteriëel besmettingsgevaar ( darmbacteriën). Bij regenval wordt de neerslag via droge beddingen naar het stuwmeer gevoerd, deze droge beddingen worden echter ook als latrine en vuilstort gebruikt door bewoners van de krottenwijken langs die droge beddingen. Dus wat zou er in het slechtste geval nog meer in kunnen zitten? Met andere woorden: a. ik heb een ingevroren flesje water, die kan eventueel op de een of andere manier naar jullie toe, voor eventueel nader ( chemisch, biologisch) onderzoek ; van welke school zijn jullie, in welke stad? Ik woon onder de stad Groningen. De maand september vanaf komende week dus) ben ik overigens niet bereikbaar ( in het buitenland). b. wat zijn belangrijke criteria voor schoon water en hoe controleer je die? c. zijn er kleinere, simpele maar wel zeer betrouwbare watertesten ( eventueel te ontwerpen) voor in het veld die aldaar te gebruiken zijn? d. hoe ziet de lokale situatie er exact uit, welke gegevens zijn daarbij van belang voor jullie onderzoek en hoe is daar achter te komen? En hoe zit het met gebruik van bestrijdingsmiddelen aldaar? e. wat zijn zuiveringsmethoden voor waarschijnlijk sterk vervuild water (met bijvoorbeeld E.coli, chemicaliën zoals ....), hoe controleer, meet en monitor je de effectiviteit van het zuiveringssysteem, , wat bepaald de capaciteit, hoe zorg je voor een doorstroming, gebruik je helophyten, verdampingsystemen, enz. ; een soort vergelijkend onderzoek naar ervaringen met diverse systemen en principes. welke zouden voor situaties zoals in Namibie het meest geschikt zijn? zijn er prototypen te bouwen, uit te testen?
veel succes met het opstarten van jullie onderzoek! met vriendelijke groet, Frits Sibers
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-----Oorspronkelijk bericht----From: sam vruggink Sent: Friday, August 28, 2015 9:11 AM To:
[email protected] Subject: Water sample Hallo meneer Sibers, Ik (Sam Vruggink) en mijn partner Shane Konijnenberg doen worldschool. Ik had naar Christien gemaild voor een water sample van het water in Windhoek. Kunt u ons misschien vertellen wat er in het water zit zodat wij verder kunnen met het onderzoeken hoe we dit moeten zuiveren. Hartstikke bedankt Met vriendelijke groet Sam Vruggink Verzonden vanaf mijn Huawei mobiele telefoon =================================================================== ===============Hello Sam,
My name is Christien and I am the founder of Penduka in Namibia. I do live in Groningen and I have The Dutch nationality so you can write to me in Dutch if you like. to answer your questions: last year a water sample was taken and given to Worldschool tutor and biologist in Groningen Mr Frits Sibers
[email protected] You can contact him for more of that information. The name of the waterdam is Goreangabdam and you can even try to approach the Municipality of Windhoek ( Gemeente Windhoek) to obtain more information of the water from then. Up till now they have not been very helpful with info concerning the water but it is worth trying again. Please make your report in English. Thank you for choosen Penduka as your project, Wishing you goodluck and good learning scope while working on it. Kind regards,
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Christien Roos Penduka founder/advisor From: sam vruggink Sent: Thursday, August 27, 2015 5:47 PM To:
[email protected] Subject: Samples Hello Christien, I am Sam Vruggink and I am doing worldschool together with Shane Konijnenberg and Chris Karssen (teacher) We have some questions. How do we obtain a sample from the water there? Or is there a overview with what is in the water? Do we need to make the PWS in English or in Dutch? Thank you in advance Kind Regards Sam Vruggink
Beste Sam, Dank voor je mail en jullie betrokkenheid bij het Penduka project. We waarderen het dat jullie de presentatie volgende week zo goed als mogelijk willen voorbereiden en het er mooi willen uitlaten zien. Dit heb ik vaker gedaan en ik moet zeggen dat het altijd tijd en geld koste om spullen te pakken en weer heen en weer te sturen , er vaak wat weg raakt en dus heel vaak een beetje nare bijsmaak geeft terwijl er heel veel informatie over Penduka op het internet staat. Jullie mogen onderdelen van de Penduka website, www.penduka.com gebruiken en als je wilt kan ik nog wat gerelateerde foto’s doorsturen die te maken hebben met water en het belang van de zuivering. HIerbij sluit ik een booklet bij die we op de Penduka locatie gebruiken als ‘gids boekje’ hoor graag of dit afdoende is of dat je nog wat extra info nodig hebt,
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groet en succes, christien penduka
From: sam vruggink Sent: Saturday, December 05, 2015 12:02 PM To:
[email protected] Subject: Worldschool Beste Christien, Wij doen het water zuiverings project voor Worldschool. Is het misschien mogelijk dat wij bij de presentatie op onze school en de presentatie voor Worldschool wat attributen kunnen lenen. Ik heb het over posters, folders over Penduka en misschien wel wat die vrouwen er allemaal maken. Dat zou de stand een stuk leuker maken. Is dit te regelen? De twee presentaties duren nog even maar dan is het alvast geregeld. Mvg Sam Vruggink =================================================================== ===============
Re: Water transportation christien penduka
Dag Sam,
Het water komt vanuit omliggende rivieren die via berglandschap allemaal uiteindelijk in het laagste punt terecht komt. Dit laagste punt is de Goreangabdam, die jij op de foto hebt aangegeven. 65
sorry, ik weet niet hoe ik met een stippellijn dit kaartje moet bewerken. Het water moet gebruikt worden bij Penduka, (wat op de kaart als Penduka Crafts aangegeven staat) daar is de nederzetting die het nodig heeft.
hoop dat het duidelijk is,
succes,
groet, christien penduka
From: sam vruggink Sent: Thursday, October 22, 2015 11:29 PM To:
[email protected] Subject: Water transportation
Beste Christien,
Wij hadden een vraag over het water dat naar het dorp toe moet. Wij begrijpen niet precies waar het heen moet. Zou u misschien deze afbeelding willen downloaden en daar een stippellijn op aangeven.
https://gyazo.com/c13a691bd1e2d999dc9c5f446e955b45
Met vriendelijke groet, Sam Vruggink
66
