The WASHTech project has published a literature review [1] focusing on 14 technologies used in Africa in the water, sanitation and hygiene (WASH) sector.
Descriptions for each technology include a selection of interesting case studies, and an explanation as to whether the technology meets technical, financial, social and institutional success criteria.
Only two technologies met all four success criteria: hand dug wells and the India Mark II pump, and the latter only with the caveat that there was a functional maintenance system.
The least successful technology was the Playpump. Pending further research, jerry cans and the gulper were only found to meet one success criteria (technical success). Except for bio-additives to pit latrines and Playpumps, all other technologies were technically successful. The other success criteria were met by roughly half of the technologies.
Core issues that WASHTech plans to take up further include the appeal of inappropriate technologies like Playpumps and Lifestraws to naive donors, and ways to get government approval for low-cost, locally managed technologies like rope pumps, biosand filters, constructed rainwater harvesting jars, water jetting and tippy taps.
[1] Parker, A. et al., 2011. Africa wide water, sanitation and hygiene technology review. (WASHTech Deliverable 2.1). The Hague: WASHTech c/o IRC International Water and Sanitation Centre and Cranfield: Cranfield University. 93 p. : 1 box, 9 fig., 1 tab. Includes references.
Available at: http://wp.me/a1szDW-1o
The aim of the WASHTech project (2011-2013) is to introduce a robust Technology Assessment Framework (TAF), with local partners in Burkina Faso, Ghana and Uganda, that will assess the potential of new innovative WASH technologies. WASHTech is co-funded under the 7th Framework Programme of the European Commission’s Africa research programme. To learn more go to washtechafrica.wordpress.com
The University of South Florida’s (USF) Patel School of Global Sustainability through its Center for Global Solutions launched the first Patel Grand Challenge at the International Water Association’s Development Congress in Malaysia on 21 November 2011. The challenge invites inventors in developing nations to create a low-cost and easy-to-use water purification device that could save millions from the perils of contaminated drinking water.
The challenge was issued by Dr. Kiran C. Patel during the congress’ opening ceremony to over 600 delegates from around the globe. (To access more details, conference photos, and press coverage go here)
The challenge welcomes pre-proposal submissions through March 2012. Five applicants will be shortlisted and awarded up to US$ 8,000. The five finalists will be invited to prepare full proposals that will be reviewed by an international panel of experts at a major event. The winning proposal will receive up to US$ 100,000.
More on the Patel Grand Challenge and the Patel School of Global Sustainability can be found at www.psgs.usf.edu
Deep Springs International (DSI), a non-profit organization based in Pennsylvania, USA, and Nokia Research Center (NRC), Palo Alto, California, are teaming up to ensure the supply of clean drinking water in Haiti with NFC (near field communication) technology.
DSI has been delivering water treatment systems (which essentially consist of a covered 19-liter bucket with a spigot at the bottom) and a locally manufactured chlorine solution it has labeled Gadyen Dlo (Creole for "water guardian") since 2007.. Photo: Michael Ritter, DSI
Water treatment kits are being provided to track chlorine levels in household drinking water using NFC-enabled cell phones. NRC provided the health workers with approximately 50 Nokia 6212 NFC-enabled phones while UPM RFID supplied UPM BullsEye™ NFC tags with NXP Mifare Ultralight chip. Joseph “Jofish” Kaye, Senior Research Scientist, NRC, initiated the project together with David Holstius, a student and Ph.D. candidate at the University of California, Berkeley’s School of Public Health, who developed the software application for mobile phones.
Families in the most rural areas in Haiti will have one water treatment kit consisting of a five-gallon (19 litre) plastic bucket with a lid and spigot. The RFID (radio-frequency identification) tags are attached to buckets for storing the treated drinking water and delivered to families together with a chlorine solution and written instructions for using the kit. When DSI’s water technicians visit their homes, they check whether they are using the kits properly and provide additional chlorine solutions. The technicians will read the tags using NFC cell phones loaded with software guiding them to ask relevant questions about the water being tested. They then send the data to DSI’s headquarters via SMS. The software application uses the Frontline SMS platform.
Stanford University is testing an inexpensive water filter, suitable for developing countries, that removes bacteria quickly and without clogging. The filter uses a piece of cotton treated with nanomaterial inks, that kills bacteria with electrical fields but uses just 20 percent of the power required by pressure-driven filters.
The Stanford filter, which is driven by gravity, has pores large enough to allow for a high flow rate–about 100,000 liters per hour. It uses electrical pulses to inactivate bacteria by poking holes in their cell walls. The research was led by Stanford materials science and engineering professors Yi Cui and Sarah Heilshorn.
To make the filter, researchers dip a piece of cotton batting in a water-based carbon-nanotube ink, let it dry, then dip it in an alcohol-based silver-nanowire ink and let it dry again. Cui and others have used similar dipping methods to make paper-nanotube battery electrodes and nanotube textiles. The long, narrow nanotubes and nanowires get enmeshed in the fibers.
Speedy sterilization: A Stanford researcher pours water through a funnel fitted with a cotton-nanotube filter that rapidly kills bacteria. The red cords supply electricity to the device, which uses electrical fields to poke holes in the bacteria. Photo: Technology Review
In preliminary tests, described online in the journal Nano Letters, the filter inactivated about 98 percent of E. coli bacteria.
In the tests, a wire, connected to an electrical power source, which could be car batteries or solar panels, is immersed in the water filter. The researchers think that the strong local electrical fields, which are formed at the tip of the silver nanowires, piercing the cell walls. When the electricity is off, the silver (which has antimicrobial properties) prevents bacteria from fouling the surface, a common problem with filters.
There have been no definitive studies of the effects of water-borne carbon nanotubes and silver nanowires on people and lower organisms; experiments with airborne carbon nanotubes have shown that their effect on mice lungs is similar to the effect of asbestos. But early tests on thousands of gallons of water suggest that the nanomaterials are not leaching into the water. The researchers will perform further tests to determine whether the nanomaterials remain enmeshed in the filter or are dislodged into the water over time.
The next step required is to improve the filter’s efficacy and show that it can work with a broad range of water-borne pathogens, including viruses and protozoa.
Watch the related video “Making a Nano-Water Filter for the Developing World”
M.K. Stalin, Deputy Chief Minister of Tamil Nadu since 2009
The Deputy Chief of Tamil Nadu state, India, Minister M.K. Stalin [!] launched, on 25 August 2010, a programme for distributing, free of cost, Terafil water filters to anganwadi centres [kindergartens] by handing over such filters to representatives of 20 centres located in Kancheepuram and Tiruvallur districts.
The low-cost filters, designed by the Central government’s Department of Science and Technology and Central Institute of Plastics Engineering and Technology (CIPET), could be maintained easily and without power supply.
It had been proposed to distribute, through the CIPET, 30-litre capacity filters free of cost to anganwadi centres.
During the current year [2010], 3,000 anganwadi centres would be covered in the initial phase, according to an official release.
A gadget that purifies and converts muddy water into potable water has been designed by a British student who will introduce it in India over the summer before producing it on a mass scale.
Oxfordshire-based student James Bartlett, 23, has designed the cheap and simple way to purify muddy drinking water without electricity. The gadget reportedly has the potential to provide millions of people across the world access to safe drinking water.
James Bartlett (right) showing the BlueDrop chlorine dosing system at Made in Brunel 2010
Adding chlorine is one of the cheapest and safest ways of disinfecting dirty water, but previous attempts have been either too expensive, or have not mixed the gas in the right amounts.
Bartlett’s invention has been to create a chlorination unit that costs just US$ 2 (Rs. 100 approx) to manufacture, and he is now waiting for a patent.
The gadget, named ApurvaJal (Hindi for “wonderful water”) works by harnessing the Venturi effect, which is used in carburettors to suck petrol into an engine’s air stream.
In Bartlett’s design, dirty water passing through a tube will suck in chlorine, which cleans it enough to make it drinkable.
He said early experiment showed it worked so well that, once perfected, it could make River Thames water clean enough to drink.
His invention, which he designed while studying a BSc in Industrial Design at Brunel University, was runner-up in the Xerox Innovation Award, presented to students who have come up with the best new inventions.
Bartlett said: “When this has been done before, it has had thousands of complicated metal parts to make it work, which you cannot get in rural India because the cost is too high. This project has been about designing one as cheap as possible which needs only three parts.”
He will spend his summer in Kolkata, India, getting feedback from people and perfecting the design before it is produced on a mass scale in India.
He said: “We want to turn it into a viable business which we can set up quickly if it works. I have tried it in the laboratory and I have been testing it in my sink at home. I’m prepared to give drinking river water a go, but a little bit more work needs to be done before I would want to try. If it works, it could save thousands of lives around the world.”
ApurvaJal is being produced by BlueDrop, previously known as LoChlorine when the project was initiated at the International Development Design Summit in Kumasi, Ghana in July 2009. BlueDrop’s founder and CEO, Suprio Das, grew up in the outskirts of Kolkata and has been working with NGOs in the region for the past 7 years.
Multi Purpose Industries (MPI), a Dutch company specialising in potable water solutions, has launched a state-of-the-art decentralised water purification unit in Kenya. MPI has invested over US$70 million in the project.
The purification unit is able to produce approximately 45,000 to 75,000 litres of potable water per day from any polluted source of water.
Multi Purpose Water Unit. Photo: MPI
Deputy Prime Minister and Minister for Local Government, Musalia Mudavadi, said the plant would increase accessibility to clean water and reduce dependency on rain.
MPI said the plant has the capacity to desalinate salty sea water and would be launched in Mombasa, at the coast of Kenya, shortly.
The investment will come as a relief to residents of Mombasa who recently experienced water shortages.
Last December [2009] the water shortages facing the tourist resort town reached crisis levels as local residents faced threats of contracting water borne diseases while tourist hotels made losses in purchasing the commodity.
The Ambassador for The Netherlands to Kenya, Laetitia van den Assum, said the water purification unit project would provide 1.3 million Kenyans with sustainable supply of water and another 1.6 million with sanitation.
Arnold Ongwerboer de Visser, chief executive officer of MPI Netherlands, said the project would stimulate local economic growth as refined water surplus is used for irrigation and reduction of waterborne diseases.
MPI is targeting private investors, government and non-governmental organisations to purchase one of the units for approximately Ksh.6 million ($75,000).
Antenna Technologies (Switzerland) has developed WATASOL, a household water treatment and storage (HWTS) approach that integrates health education with the local production of chlorine in a sustainable supply chain, making safe water treatment an income generating activity for local communities.
WATA Devices
A WATA device requires water, salt and electricity. When immersed, and connected to a reliable source of electricity, a process of electrolysis takes place, converting the saline solution (sodium chloride) – with 25 grams of salt per litre – into active chlorine (sodium hypochlorite).
Three on-site chlorinator models are available:
Mini-WATA kit: 0.1 litre active chlorine/hour, serves 240 people (€ 40, excl. shipping)
WATA Kit: 1 litre chlorine/hour, serves 2,400 people (€ 200, excl. shipping)
In order to measure the chlorine concentration in a chlorine solution, Antenna Technologies has developed the WataTest reagent.
Available in 50 Countries
WATASOL devices are in operation in almost 50 countries, through community-based organisations, NGOs and local community and private enterprises. In 2009, Antenna Technologies introduced a franchising model with community enterprises.
"Uzima Mamas" in Goma, DR Congo, who sell water disinfectant produced by WATA devices. Uzima is a Swahili word with many meanings including abundance, fullness, wholeness, health, life and clean water
New Pilot Projects
With support of UNICEF in Mali, and the Swiss Development Cooperation Agency and Caritas Switzerland in South Asia, Antenna is launching two WATASOL major pilot projects. Their objective is to
To provide an autonomous and sustainable solution for safe drinking water at household level based on local production of chlorine through electrolysis
To control the quality of the produced chlorine and of the drinking water after the chlorination
To create income generating activities based on the local production and distribution of the concentrated chlorine solution to contribute to the promotion of HWTS
To establish methodologies for the implementation, monitoring and evaluation of domestic safe water through the local production and sale of chlorine
To document and capitalise these experiences in order to replicate them
To prepare a “scaling up-phase” based on the know-how and lessons learned.
Mali
This project, which is supported by UNICEF aims at improving the quality of domestic water for 50,000 people in four priority zones in Mali.
The local production of chlorine would also allow health centres of these places to use a high-standard and cheap disinfectant. The following local NGOs are responsible for the implementation of the project in the identified zones:
The NGO Le Tonus runs a programme to fight cholera, which persists in the region of Kayes.
Formations Sans Frontières will equip ten health centres in the Mopti region with the active chlorine production systems, run with solar panels.
Aidemet works on the promotion and local production of chlorine in partnership with Antenna Technologies in the district of Kadiolo (Sikasso region).
AS EDEN plans to use electro chlorinators to treat water from wells in the municipality V and the suburban zone of Bamako (Ganouan).
ASACOBA works in partnership with Aidemet in the urban zone of Bankoni for the promotion of the local production of chlorine.
These zones of intervention have the advantage of representing a large spectrum of different situations: urban, rural and suburban settings; precisely one of the objectives of the project is to document the feasibility of the local production of chlorine of HWTS in diversified contexts.
South Asia
Antenna Technologies launched a two-year WATASOL programme together with its four partners. The aim of this programme is to develop viable economic models generating income for the people involved in the sale and promotion of chlorine.
Here is a brief overview of the partners and their implementation plans:
Environmental Camps for Conservation Awareness (ECCA) – Nepal: The objective of this project is to promote access to drinking water in schools and communities to prevent water-related diseases in the centre and the east of Nepal.
At the school level, the emphasis will be on raising hygiene awareness, access to safe water as well as to the reduction of sickness absences in schools. The production and the dissemination of the flasks of chlorine will be done by social entrepreneurs who ensure the quality of the product, its regular use and the hygiene consciousness.
Vertical Shaft Brick Kiln (VSKB) – Nepal: This project aims at improving the access to safe drinking water for workers and their families in four brickyards in the valley of Kathmandu. The collected data shows that the productivity of the workers is impaired by waterborne diseases. The objective is to get to a win-win situation between the workers and entrepreneurs.
Development Alternatives (DA) – India: The aim of this project is to provide safe water systems to ten slums of New Delhi through the sale of chlorine produced by social entrepreneurs. The chlorine will be injected directly into the containers with water of the households. This project is combined with a large awareness-raising campaign among the communities.
Centre for Mass Education in Science – Bangladesh: The production of chlorine will be realised by trained disadvantaged young women who will be responsible for the promotion of hygiene and the sale of chlorine. This activity should generate a stable income for these women.
Founded in 1989, Antenna Technologies is a non-governmental organisation based in Geneva, Switzerland. It is primarily a network of scientists, researchers and engineers working in tandem with a communications & coordination team. Funding comes from foundations, private donations and institutional funds.
A resident of Kathmandu has adopted ecological solutions to cope with the city’s persistent water shortage and power cuts.
Report of a visit to Dr. Shrestha’s Eco-home on 14 March 2010.
Dr. Roshan Raj Shrestha in his Eco-home. Photo: C. Dietvorst
Dr. Roshan Raj Shrestha built his Eco-home in November 2002. The two and a half story building is neither connected to the city water supply nor to the sewerage network. It uses several kinds of water conservation methods including rainwater harvesting, greywater recycling, ecological sanitation, Solar Water Disinfection (SODIS) and organic waste composting. Dr. Shrestha says he was able to recover the extra investment of US$ 1,000 for his water conservations systems within three years.
The Eco-home has helped Dr. Shrestha cope with Kathmandu’s severe water crisis. The public water supply can only meet half of the actual demand and the city’s Bagmati river is turning into an open sewer. The ground water level is decreasing by 2.5 metres a year due to over extraction. The mega Melamchi Water Supply Project, started in 1998 to tackle Kathmandu’s water crisis, has been plagued by delays.
Rainwater catchment terrace and tanks. Photo: C. Dietvorst
With an average annual precipitation of 1,600 mm in the Kathmandu Valley, Dr. Shrestha found that rainwater would provide with enough water for his family of five. Rainwater is collected on two roof terraces and stored in a 9,000 litre underground tank. Excess rainwater is diverted into a dug well, which acts as an intermittent tank that can store nearly 10,000 litres and also supports shallow groundwater recharge. SODIS is used to treat rainwater for drinking water, while water from the dug well is pretreated first in a biosand filter.
Residents constructing new houses in Kathmandu now get a 10% tax rebate on their building permit fee if they include a rainwater harvesting system in their design. The rebate can reach 30% in other municipalities in Nepal, says Prakash Amatya, the Executive Director of NGO Forum.
No water goes wasted in the Eco-home. Dr. Shrestha has installed a urine diversion dry toilet in his master bedroom. Urine and composted feces are used as garden fertilizer. A small reed bed treatment system is used to recycle grey water for garden watering, washing the car and for an extra flush toilet.
Solar panel. Photo: C. Dietvorst
The latest addition to the Eco-home is a 100-Watt Solar House System (SHS), installed in 2009. The solar panels provide enough energy to light the lamps in the house. Costing US$ 1,000, the system is only affordable for middle-class families, Shrestha admits, but it has proved its worth now that power cuts of up to 12 hours a day have become standard in Kathmandu.
Dr. Shrestha is proud of his model Eco-home. He is happy to give visitors and groups of students a tour. He finds that people readily accept the concept of rainwater harvesting and greywater recycling. They are not so keen about ecological sanitation though, because of the socio-cultural barriers associated with feces.
Eco-home for sustainable living, Himalayan Times / UrbWatSan Nepal, 19 June 2009
Eco-home for sustainable water management : a case study in Kathmandu, Nepal. Ministry of Physical Planning and Works / UN-HABITAT. October 2008 (brochure)
Shrestha, R.R. (2007). Sustainable water management : a case study in Kathmandu. Presentation at Ecosan – Fortaleza 2007
SODIS water bottle. Photo: C. Dietvorst
Reed Bed Treatment System for greywater recycling. Photo: C. Dietvorst
A question: if we can fly to the moon, can we make a 1$ water filter for people to use in their homes? And, if the answer is yes, why haven’t we yet? This is one of my favourite things: the quest for extremely affordable point-of-use water filters.
There are some hopeful developments. After Hindustan Unilever had introduced their Pureit water purifier at a price level of 30$ for a very well-designed and effective water filter, protected by 21 patents and using 5 water filtration steps, Tata Company recently introduced their Tata Swach water purifier, at 20$, with 1 filtration step, but equaly good-looking. And we already had the Vestergaard Live Straw Family filter, also at 20$. In the open source hardware corner, we have the biosand filters, and ceramic pot filters. Lots of good stuff.
These filters all use some combination of microfiltration, disinfection and adsorbtion. Microfiltration simply blocks bacteria from passing through the filter by using a highly porous material in which the bacteria bacially get lost. Disinfection, for example using chlorine, kills bacteria and other pathogens using chemical means. Adsorbtion, finally, uses carbon to adsorb molucules, improving taste, smell, and colour of the water. Not all filters use all three, and this is where the main differences in quality lie.
How a siphon filter works
The Siphon filter
So — 30$, 20$, can we go lower? Enter the siphon filter. Produced by Basic Water Needs Foundation India, and sold under the brand name Tulip filter and CrystalPur, it is sold for 10$. To reach that price point, the filter has been designed in such a way that only the most essential elements remain: a filter element, a tube, a tap. That’s it.
The ceramic filter element is made out of diatomaceous earth, a wonderful substance consisting of the fossilized remains of diatoms, a type of hard-shelled algea. Their beautifull little skelletons contain extremely small holes, which are very suitable to act as a bacterial filter. The filters are impregnated with silver particles, which reduce regrowth of bacteria. Allhough bacteria are filtered effectively, candle-type ceramic filters have lower removal efficiency for viruses. To effectively remove these, ceramic filter filtration needs to be combined with a disinfectant such as chlorine.
Siphon filter demonstration in Mozambique
Why it is smart
The brilliance of the filter lies in the tube. Because a ceramic filter is highly porous, it needs a certain amount of water pressure to push the water through. In the Siphon filter, the tube is used to siphon the water from a higher water container to a lower one, creating about 70cm of water pressure. This is enough to suck the water through the filter, creating a flow rate of about 5 liters per hour. Plenty.
The filter is cleaned by closing the tap and squeezing the rubber bulb, which pushes clean water back through the filter, which cleans it. Called ‘backwashing’, this significantly prolongs the lifetime of the filter. It’s small size makes it easy for small hardware and general stores to keep it in stock, and to distribute it on a large scale for emergency situations. The costs are kept low as storage pots for the water are not included: the filter can be used with storage pots that people already have.
At the moment, the filter is being implemented by EnterpriseWorks/VITA, and Connect International in Cambodia, Tanzania, Mozambique, Madagascar, Kenya, India, and other countries. Good luck people!
The WASHTech project has published a literature review [1] focusing on 14 technologies used in Africa in the water, sanitation and hygiene (WASH) sector.
