Clean Water for the Developing World

During the first 48 hours of the response to the recent Haiti earthquake disaster, EcoThought was asked by a US based experts advisory group to undertake a very rapid survey of options to supply clean water to individuals and families in the disaster zone . Our researcher undertook some rapid research to identify some options avaialble. The research was by no means exhaustive, but it did raise some interesting options, the most notable of which is a device called the lifestraw, although the Proctor and Gamble PUR packets are also a great option - their only drawback being the need to maintain a clean bucket for decanting the fresh water (a classic systems problem - to poor families a bucket is an extremely adaptable piece of equipment with many uses. Ensuring that one bucket remains clean at all times could be a challenge).

Anyway, I have included the key notes which our researcher pulled together as the information may be useful to others faced with similar questions.

PUR Packets -

Children’s Save Drinking Water Programme is part of Proctor & Gambles Health Sciences Institute’s work in collaboration with a number of international organisations such as UNICEF, CARE, Save the Children and World Vision.  As part of this program P&G developed a system for easily purifying water that was also easily transported and distributed.  Known as the PUR Packet, this system was developed in conjunction with the US Centre for Disease Control and Prevention. 

The PUR packet is a powder that removes suspended matter as well as microbial pathogens.  The claim is that the PUR packet removes “99.99999% of intestinal bacteria, 99.99% of intestinal viruses and 99.9% of protozoa”. 

“P&G provides PUR Purifier of Water to global relief agencies, including UNICEF, the International Federation of the Red Cross and Red Crescent Societies, AmeriCares, Samaritan's Purse, CARE, Population Services International, Save the Children, World Vision, and others so they can provide drinking water in emergency situations.”

Prior to the earthquake in Haiti, PUR was already being using in the country as part of a collaboration between P&G, PSI, Partners in Health, Johns Hopkins, and others in providing over 30 million litres of safe drinking water.

As this program was running prior to the quake, it makes sense to see if these organisations are intent on continuing and expanding their work in this current crisis.

P&G makes PUR available at cost to international relief groups, with 1 PUR packet purifying 10 litres of contaminated water.

The person behind the P&G efforts is a Dr Greg Allgood.  He has a Ph.D. in Toxicology from North Carolina State University and a Master of Science in Public Health from the University of North Carolina-Chapel Hill.   He is currently the Director of the Children's Safe Drinking Water Program at Procter & Gamble, is a Senior Fellow in the Sustainability organization, and leads P&G's efforts to provide clean drinking water in the developing world.  Dr. Allgood is also currently the chair of the communications and advocacy group of WHO's International Network to Promote Household Water Treatment and Safe Storage and serves on the advisory board of the Aquaya Institute.

The use of this product seems very simple.  Requirements would be 2 x 10 litre (minimum) containers, cheesecloth (or equivalent for additional filtering) and 1 x packet of PUR.  The PUR is mixed with the contaminated water, the large solutes settle to bottom leaving water clear and clean.  The water is then poured through the cheesecloth into the second container.  No electricity, heating, etc, required.

Ref - http://www.csdw.org/csdw/home.shtml

LifeStraw and LifeStraw Family –

These are filtration systems designed specifically for “point of use”.  Designed by Vestergaard Frandsen, these systems are very easy to use and are designed for in and outside of the home.

The LifeStraw is very portable, being designed to be carried around.  It filters up to 700 litres of water.  The literature on this device does not indicate whether there is some ‘metering’ system on the straw to enable users to tell when it has reached its maximum usage level.  The straw is designed to be used in conjunction with the LifeStraw Family.  This would extend the time it would take for users to reach 700 litres.

The LifeStraw is very easy to use.  The only thing users need to be made aware of, is that they need to “regularly blow through the LifeStraw after drinking to keep the filters clean and to prevent clogging.”

The LifeStraws remove 99.9999% and 98% of waterborne bacteria and viruses respectively.  They also remove particulates down to 15 microns.

This is a very efficient means of filtering water.  It does not require the users to mix chemicals, measure liquids, etc, etc.  The straws are light and very easy to distribute.

LifeStraw Family is “a fully-integrated, gravity-fed, point of use microbial water treatment system intended for routine use”.  It removes a minimum of 99.9999% of all bacteria, a minimum of 99.99% of all viruses and a minimum of 99.9% of all protozoan cysts. 

In addition –

1. it has a high flow rate of between 8-10 litres per hour. 
2. It works effectively in highly turbid water.
3. Is known to be effective in filtering up to 20,000 litres of water (although Vestergaard Frandsen found that when testing there had been no decrease of effectiveness at that level of usage and so is considered effective beyond this level).
4. Requires no power sources i.e. batteries or electricity.
5. Requires no connection to a piped in water supply.
6. Requires a small amount of maintenance in relation to cleaning the filter and purification cartridge.
7. Designed for long lasting usage.

The LifeStraw Family has only 7 parts, none mechanical.  It would require the recipients to be trained in its usage and daily cleaning of cartridge (no removal or extra water required) and filter (requiring cleaning with a cloth and clean water).

Probably the most important thing to note with this system is that in conjunction with the LifeStraw, this system is an immediate solution, with the added advantage of also being a medium term solution.  (More bang for your buck!) In addition, it has greater effectiveness in dealing with protozoan cysts, which chlorination does not do as effectively.

As Vestergaard Frandsen is a company that is a specialist in emergency response and disease control products, it may be that they have capacity to provide adequate units of the LifeStraw and LifeStraw Family.  However, this is a company that has turned humanitarian responses into its core business.  The cost per unit of the LifeStraws and LifeStraw Family are not known.

In addition to water purification, Vestergaard Frandsen are also leaders in Disease Control Textiles.  They have two products, PermaNet and ZeroFly, that may also be of use in relation to mosquito born diseases.

 Ref - http://www.vestergaard-frandsen.com/lifestraw.htm

 There are similar products on the market, ‘Survival Straw’(US), ‘AquaSafeStraw’(US), ‘iStraw’(UK/Aust).  These are designed for use by campers and trippers and on average are good for around 500 litres.

 Solar Water Purification -

Utilising solar rays to destroy water borne pathogens, these systems range from small ‘brief case’ sizes to larger ‘trailer’ sized systems.  One organisation that utilises solar systems in emergency relief is Aqua Sun International.  Their most recent work, documented on their web page, is the 2007 flooding in Bolivia and the 2005 tsunami in Indonesia.

Their smallest system weighs in at around 35 pounds and can produce approximately 1 gallon per minute, while their stationary or mobile trailer systems can produce 10,000 to 15,000 gallons of drinking water per day.  The systems require no external electricity or use of chemicals.

Their system is claimed to have the capability of “producing cleaner and safer drinking water from almost any creek, stream, pond, well, lake or fresh water source”.  The system uses a 5.0 micron sediment pre-filter before pushing the water through a 0.5 micron carbon block polishing filter before the filtered water is channelled past a UV light disinfecting process “to a 99.999% purity”.

 A problem associated with UV and solar systems relates to the turbidity of the water being processed.  The more turbid the water, the less effective UV and solar rays can be.  Obviously filtering would be a key factor in the systems effectiveness. 

 A greater issue is the complexity of the system.  It is not something that can just be picked or connected up and used.  It might, therefore, be a more practical medium to longer term solution.

 Ref:  http://www.aqua-sun-intl.com/PWP-C.htm

 Water Purification Tablets –

 There are a number of forms of tablet purification available.  I note that CARE has already started to distribute water purification tablets in Haiti.  The hiccup in their program is that the recipients require two buckets, and many do not even have one.

 Most purification tablets are designed to clump and bring particulates to the surface of the water.  This takes time – usually thirty minutes.   I am not sure if too many people would have time pieces, so I am not sure how they would ‘time’ the process.  It also means that apart from two buckets, people would require some kind of filtering material to capture all the dissolved solids.

 Different strength tablets are used for different amounts of water.  Before any variety or brand is used, the pathogens, viruses, etc, that it is effective against, would need to be checked.

 AquaTabs seems to be one of the most widely used brands.

 Ref:  http://aquatabs.com/aquatabs-water-treatment-tablets/what-are-aquatabs-water-disinfection-tablets.html

Research undertaken by Amanda L. Beard.