Arsenic Contamination in Well Waters of Bengal
Our Involvement
For 12 years now, we have played an advocacy role to mobilise action to help the tens of millions of people who live in West Bengal and in Bangladesh and find that their groundwater supplies are heavily contaminated with arsenic. It is difficult to estimate precisely how many are afflicted but it is in the neighbourhood of 100 million people and at that sort of level it ceases to be important to be precise. Likewise, the number of contaminated wells is difficult to estimate but 5 million would not be an overstatement. The numbers dying is controversial since it is often difficult to isolate arsenic poisoning as the lethal cause but the total casualty figure is likely to be in the hundreds of thousands by now.
The reason we got involved was a request that we look into the situation from an Indian official who knew of our interest in high end water purification technology as well as in rural development. We asked Aapo Saask of Scarab AB, our advisor in Sweden, and he ran tests using Swedish laboratories to investigate remediation. It was found that Membrane Distillation removes all traces of arsenic III and V no matter how high the level of contamination in the feed water.
We reported this to our friends in Calcutta as well as to the Swedish Ambassador to India. The Ambassador, Mr Engblom, a humanitarian, asked that we obtain an official request for assistance from the West Bengal Government to test the technology in the field and Mr Gautam Deb, the relevant Minister at the time furnished an official request. It was discovered that the request had to be from the chief minister and Mr Joyti Basu, the Chief Minister made an official request. We were then told it had to be endorsed by the central Government and was submitted only for the Indian nuclear tests to lead to suspension of Swedish aid. Moreover, when the suspension was finally lifted, the Vajpaye BJP Government refused most bilateral aid. When the path was finally clear and we had been told to find a private investor which we did, we were told that it did not fall within the country programme. Usual run around!
The Indian Government is perfectly willing and able to pay to solve the problem and has allocated more than adequate funds for the task. A problem is that the state governments are often very short of cash and money has not ended up solving the arsenic problem. There was, in any case, no agreed solution.
Having become involved in the arsenic problem, we were advised to turn our attention to Bangladesh to avoid the pitfalls in India. The first efforts were rebuffed on the gronds that the Danida programme had found a cheap and effective solution, proved an illusion, that the World Bank had been charged to solve the problem and was adequately financed for the purpose. When this proved untrue, we were told to find a NGO partner, which we did, and finally told bluntly that nothing worked in Bangladesh, so forget it.
Not easily disuaded, we campaigned for attention tothe problem in Sweden, continued to hassle the Swedish Embassy in Dhaka, talked to the World Bank, UNICEF, the Deputy British High commisioner, DFID and anyone else we could reach. We ran out of money to pursue this lobbying and it revived only with an interest from Grameen and Grameen Shakti.
Strategy Options
The strategy followed so far is to tell the world how bad the situation is, call for funds to help solve it, spend the funds on overheads, studying how bad the situation is, telling people not to drink from contaminated wells and providing a few with deep tube wells. While this could be argued as an emergency measure it does not amount to a strategy.
The main strategy options are:
1 Find alternative sources of water
or
2 Purify the contaminated water
Alternative Sources
The World Bank decided to screen wells, warn consumers to avoid contaminated ones, train doctors and look for alternative sources of water. The Bank applauds their own performance as one that has helped save lives by warning people about contaminated water. Amongst the alternative sources of water, they looked at:
rainwater harvesting,
deeptubewells and
ponds
and decided to provide 2,000 villages (less than 5% of the afflicted) with deep tubewells. The Bank failed to use all its allocated money and returned around 20% of it. Meanwhile a screening process to evaluate technologies staffed by Bangladesh Government tested and approved mainly absorption. We backed off going through the procedure for various reasons not related to our confidence in the technology, and so Membrane Distilation was not tested by them. Instead we tested it in Sweden and in USA.
The idea of using surface water is superficially very inviting. Techniques such as rainwater harvesting sound very green and sustainable. We had already looked at alternative sources of water. Gautam Deb told us that the West Bengal Government had found that surface waters became contaminated very fast and they were often far more lethal than the arsenic contaminated water. That made sense to us. It is a pity since Bengal has the highest rainfall in the world and is mostly swamped with water. Flooding rather than droughts are the normal emergencies. But before surface water can be used it has to be purified and water purification is expensive. We thought the same was true for rainwater. Maybe the world is moving in a direction when sooner or later all water will have to be purified before it can be drunk.
In the end the World Bank favoured deep tubewells but was restricted by the Government of Bangladesh to mainly coastal areas. Many have deep misgivings about using deeper wells. There are also serious problems in making communities that depend on deep wells to pay for use and on ownership of such wells. The World Bank has not found a good chaging model and they were tied toi 'market driven' investment where coimmunities have to pay and the system has to be sustainable.
Purification
The people suffering from arsenic contamination in Bengal are amongst the poorest in the world. They are mostly below the poverty line so what appears to be feasible in charging terms in comfortable surroundings in USA or Europe or in luxury hotels is far removed from reality. It may sound reasonable to charge for water because you cannot exist without it. Any charge on water is more than the consumers are used to and most levels of charges are more than they can afford.
That is why there is almost no water purification undertaken at community levels and only very rudimentary purification devices are being sold in India. The cost of water that could be met would have to tend towards that charged by utilities. In the long run, this means trying to get well below one cent per litre and one day 0.1 cent per litre. To fully understand the level being advocated one must realise that even soda fountains in restaurants incur a cost of one cent per litre.
Of course, there is also a market for purified water and it is large in India and growing in Bangladesh where water is sold at above 30 cents per litre to richer people and tourists in urban areas.
There are a number of technologies that can reduce levels of arsenic contamination to below 50 ppb but although that meets targets set by WHO, in USA the maximum allowed is 10 ppb and 3 ppb is favoured as the safe designated level. Absorption by compounds of activated alumina was the strongest contender certified by Bangladesh water authorities and claims to achieve safe levels at a cost of 4 cents per day per household. The reservations we have are that it achieves 10 ppb in most cases and we do not think that good enough in the long term, that it removes arsenic but not many other contaminants in surface water and leads to continuous imports of the material leading to a large foreign exchange liability.
If any solution needs to be funded through aid money, it would have to fit within the normal life of aid projects which is below 5 years. A recurrent liability that goes beyond such a time span cannot generally be funded on development funds. This consideration, however, does weigh against all technologies because the capital cost of solving this problem is going to be very large and could be made more palatable by being spread over a period of time. In no circumstances could recurrent operating cost without time limit be me through an aid programme.
We are of course connected to membrane distillation (MD) which can remove all traces of arsenic as well as all other contaminants in surface water so, in fcat,there is no necessity to use water from contaminated wells as surface water is freely available in most cases. However, the equipment is more expensive than absorption although there are no consumable costs other than heat. MD is expensive if electricity is used and that is why we are promoting it only where there is waste heat available. You can find more details from the site link below:
There were other technologies tested and ironically some of them actually added contamination, The existence of the problem has brought a lot of vendors who think they may have an answer. This has only served to cloud the issues. Most of these vendors are not only not helping but are actually harming by making claims that have to be checked out of fairness. Many of these vendors know that they do not lower contamination to safe levels but somehow want to get on the gravy train. Of course, there are others that can work and whose cliams are justified.
Filter purifiers using activated alumina can in most cases reduce arsenic to below 10 ppb but the problem is that there is a capital cost as well as a recurreng cost for media.
Areas Contaminated
Over the last 12 years, in West Bengal and in Bangladesh a great deal of money has been spent on the screening process. The areas contaminated have been well mapped:
And in Bangladesh:
There are many other countries and regions that have contamination from arsenic, fluoride or iron in groundwater. They include areas in the USA such as Alburquerque in New Mexico as well as in china, Thailand, Cambodia, Iran among a host of others. But Bengal suffers the worst.
Polygeneration as An Answer
Bangladesh is suffering from a major calamity in the form of extreme arsenic poisoning in wells in a significant part of the country which results in millions of people suffering from arsenic poisoning and hundreds of thousands who have already died. Despite the fact that the problem has been internationally recognised for over a decade, no alternative source of safe water has been developed. Although battle lines have become blurred, we are not even at the beginning of the end of the problem yet.
Over 60% of the population do not have access to electricity. In order to alleviate poverty and meet this need Grameen Shakti has launched a programme, now being applied at an accelerating pace of alternative sustainable sources of energy that includes solar power and biogas. There are technical and engineering problems that are being tackled daily to allow faster implementation. The commercial viability of the programme could be strengthened by meeting another major need in the form of access to drinking water while adding another revenue stream in the form of pure water and a technical possibility that has been proven to work is the combination of biogas electricity generation with total removal of arsenic from contaminated water.
Use of biogas and solar collectors are important cornerstones to developing renewable energy in Bangladesh. The country is rich in potential gas resources but has found in recent years that consumption of energy has been outsrtipping supply. There is, in fact, at present a serious shortage of energy. New exploratory contracts have been issued and there is every prospect of finding more gas. But it will not be enough.
Biogas is a promising technology but there are serious constraints, including: the fact that since energy prices are subsidised it is hard to be commercially viable when producing renewable energy; there is no locally produced adequate generator; and there are other technical problems. Energy produced by biogas is nearly at break-even prices but there is no great profit in it. Few are willing to fund the capital costs. Grameen shakti is one of those with a biogas programme.
Cogeneration allows use of the heat, which is roughly half the enrgy generated, while electricity is being produced and if there are commercial applications for this heat it means that returns can be doubled through better energy utilisation. There are potential applications but they will take time to develop and its a question of what comes first the horse or the cart. You have to have the waste heat before someone decides to use it.There is no ready market for waste heat anywhere but particularly in a developing country like Baangladesh.
There is also a shortage of drinking water. In part, this is due to arsenic contamination of well waters but also due to contamination of surface water from a variety of sources. A lot of people suffer from illnesses caused by poor drinking water. By combining solutions to shortages of electricity and water with use of waste heat, all three become more likely to be commercially viable. Three cash streams make the prospect of renewable enrgy sustainable. The calculations still need to be made and there has to be a field demo to allow for accurate assessments.
The rural poor find it difficult to pay for clean drinking water and most have no electricity. Grameen Shakti have a charging model that finances biodigesters to make electricity and have implemented some thousands of systems. However, the marginal viability of the system acts as an obstacle. If they are reluctant to pay a viable price for electricity, rural populations are even more reluctant or unable to pay for drinking water. Most people in the world pay for drinking water one way or another. But utilities charge very little for water that has been treated very little. The latter is simply not an option in the situation in Bengal.
With arsenic, purification is required and very few utilities undertake water purification beyond colalgulation, sedimentation and filtering. There are some who also use activated carbon and ozone but they are a minority. No utility in a developing country does that. The quality of water is poor. Most do add chlorine to water to stop it getting worse during distribution. To make it interesting to consume water that has been purified, there has to be a very low cost of production.
The main problem preventing or impeding commercial viability of electricity generated by renwables including digesters and solar is that Bangladesh heavily subsidises electricity tariffs. This makes it hard or impossible to justify renewable energy. However, if the heat is used to say dry crops and to purify arsenic contaminated well waters, the joint income contribution makes renewable energy such as digesters commercially viable.