Environmental Philosophy in the Context of Bangladesh

Md. Khalequzzaman, Assistant Professor of Geology, Georgia Southwestern State University, Americus, GA 31709, USA. URL: http://vulcan.gsw.peachnet.edu/khaleq

Bangladesh is facing a tremendous challenge as it stands at the doorstep of the 21st century. The country's economy is in disarray; the political instability has become a part of everyday life; the college campuses have turned into battle grounds; the security of ordinary citizens is threatened; the natural calamities are rampant; and the quality of water and air has become unacceptable by world's standard. Most of these problems have existed in Bangladesh in the past. However, there is no sign of improvement in the sight, and the degree of deterioration has reached an alarming proportion. Many would argue that achieving a prosperous economy and political stability should be the top two priorities for Bangladesh in order to provide a decent life for its citizens. Other issues of import would be the improvement of law and order, education, and the state of the environment. While all of the issues mentioned above are important and need to be addressed, some are more important than the others, because thy are contributing to a crisis situation and are posing a threat to our survival. The people of Bangladesh need to set their priorities straight and act upon them immediately.

Setting our priorities straight: 

If a gallop poll were conducted among ordinary citizens of Bangladesh to identify the top priority issues for the 21st century, it would probably be unlikely that the environment would top the list. This is to be expected, given the degree of environmental awareness and the average level of education on environmental that is available to people through schools and other institutions. I would, however, argue that in Bangladesh, the improvement of the state of the environment is a pre-requisite for prosperous economic development. Only a balance between the environment stewardship and economic development can guarantee a sustainable future and the well being of the country in the 21st century.

Environmental stewardship vs. economic development: 

The environment is comprised of physical (air, water, soil, mineral resources, light, and temperature) and biological (plants and animals) realms. The term "ecology" encompasses a complex interaction and the delicate ecosystems within which humans exist. Our dependence on the environment has both a short-term component and a long-term component. On one hand, since we breathe air, every minute of our life literally depends on the environment. On the other hand, the role that other components (such as, mineral resources, temperature, plants, etc.) of the environment play is not always very obvious within the timeframe of the human life span. Quite often the long-term consequences of particular human activities are overlooked in the interests of short-term gain. Mineral resources extracted from the earth's crust are the basis for civilization. Rocks and minerals are the raw materials for most of the industrial products that we use everyday (oil, gas, coal, construction materials, fertilizers, metals, rare earth elements, and radioactive elements are just a few to name). In other words, most of the products that we use to maintain the standard of living and comfort come from the environment. Therefore, economic development is just another term for exploitation of the environment. Unfortunately, most environmental components have a finite amount (i.e. non-renewable within a human life span), non-uniform distribution, and limited carrying capacity. It is for this reason that we need to understand the dynamism and the fundamental principles that govern the environment.

A better understanding of the fundamental principles and the underlying philosophy that govern the balance between components of the Earth's ecosystem can help us achieve economic development while safeguarding the environment. These philosophical concepts help us better comprehend the way our planet works, as well as will help us evaluate the extent and limitation of earth resources that are needed to attain a sustainable future. In the following few paragraphs those principles will be explored in the context of Bangladesh.

Everything affects everything else: 

The environment is a part of the "earth system", which has four interrelated components, namely, the lithospehre (the earth's outer layer), atmosphere, hydrosphere (surface and groundwater), and ecosphere (plants and animals realm). The interrelationship of various components can be demonstrated with the example of flooding in Bangladesh. Flooding is a natural phenomenon, which is a part of the hydrologic cycle (hydrosphere). Human activity (in the ecosphere), such as deforestation or soil erosion due to tillage, can reduce the water carrying capacity of rivers, causing more floods. Also, increased amounts of greenhouse gases in the atmosphere will result in increased temperatures, causing more evaporation, precipitation and floods. Volcanic eruptions (in lithosphere) can melt snow (in hydrosphere) in the mountains, causing more floods. The above examples demonstrate how all components of the earth system are interrelated. Many such examples can be drawn upon to elaborate on this point.

Humans as agents of environmental degradation: 

The earth is a dynamic planet that has maintained a delicate balance through time immemorial. Any external stress imposed upon the Earth's ecosystem can results in an imbalance among its components, much like a motor engine that would malfunction due to improper handling or mismanagement of its components. Humans are part of the ecosphere, but depend on all the other components for their survival. Although the human species appeared on Earth only recently on a geologic time scale compared with the age of the earth, humans have already proven to be a major denominator in many spheres of the environment. Humans have accelerated natural changes in the environment at a rate faster than ever before. During the last few decades the earth ecosystem has manifested many signs of unbearable imbalance in its environmental components. Examples of such signs of imbalance, as demonstrated by nature's fury, would include the increased rates of: (a) recent major flooding in Bangladesh (in 1988, 1993, and 1998) and elsewhere; (b) depletion of the ozone layer; (c) global warming due to an increase in greenhouse gases; (d) sea-level rise and coastal erosion (Bangladesh will be the most affected country should the sea-level continues to rise in the future); (e) soil erosion and desertification (northwestern region in Bangladesh is experiencing desertification); (f) cyclones (Bangladesh was hit by 7 of the 10 most devastating cyclones in the world during the last 100 years) ; (g) El Nino and La Nina; (g) tornadoes (more than 100 severe tornadoes hit Bangladesh during the last 100 years) ; (h) air pollution (quality of air in Dhaka is the worst among the major cities in the world) ; and (i) decline in bio-diversity (along with other rare species, the number of the Royal Bengal tiger in the Sundarbans is in decline).

The carrying capacity of the earth is limited: 

Exponential growth of population is the root cause of most environmental degradation. The world's population has tripled during the 20th century; life expectancy has almost doubled during this time. The world economy, fuel consumption, industrial activities, and energy consumption have increased by as much as 20, 30, 50, and 80 times, respectively during the last hundred years. This increase in population has already exerted a tremendous stress on the Earth's ecosystem, depleting many of the earth's non-renewable resources (e.g. at the present rate of consumption, the earth's oil/gas reserve will last for 25 more years); and causing environmental degradation as mentioned above. The size of the World economy will have to increase by five times to support the increasing population at the present standard of living. The resources and land needed for such economic growth are just not there. The rate of increase in population in Bangladesh is even higher than that of the world's average. The carrying capacity of Bangladesh is well above the normal average. The density of population in Bangladesh is 50 times higher than in the United States. It is a scary scenario. The rate of population growth in Bangladesh will have to decline substantially for us to be able to strike an environmental balance while still maintaining the kind of decent life that any human being deserves.

Sustainability is not enough, prosperity is needed: 

Sustainable development calls for maintaining the present standard of living while safeguarding the environment. However, simply maintaining the current standard of living should not or cannot be the ultimate goal for our future generations, for it will mean "no progress." Humans have always striven to improve their standard of living compared to that of their predecessors. Doing better than what was possible in the past is the driving force behind progress. What we need, therefore, is not sustainability, but potential for prosperity. This should translate into a prudent use of the earth's resources, as well as an improvement in the quality of the environment. Discovery of new resources, energy sources, and innovation in the use of alternative resources can help us achieve this goal. Bangladesh should develop nuclear energy and solar energy to produce electricity, and to meet other energy needs of the country.

Electrification is the foundation for economic prosperity: 

Following the October Revolution, V.I. Lenin defined socialism as "the electrification of the whole country and the transfer of power to the Soviets (people's representatives)." This goes to show how important the electrification was for over all development of a country more than 80 years ago. The need for electrification of Bangladesh remains just as important even today. I think everyone will agree that a drastic improvement of the power sector is an absolute prerequisite for over all development of Bangladesh.

To meet the growing demand of electricity in the domestic and industrial sectors, Bangladesh will have to come up with a plan for massive production of power. Because of low terrain and high population density, the prospect of developing hydroelectric power is not environmentally feasible. The oil and gas reserve of the world will eventually diminish (maybe within next two or three decades). Other means of alternative energy sources include solar power, wind power, tidal power, and nuclear power. Generation of electricity using wind requires high wind speed and available open space. Valleys within mountains can funnel winds at high speed, and are suitable locations for windmills. Parts of Chittagong and Hill Tracts might be feasible for generation of electricity using wind power. Generation of electricity using tidal power is very similar to hydroelectric power. Tidal channels are dammed of and tidal water is forced to pass through a narrow gate to which a turbine is connected. The direction of the turbine can be changed to allow both incoming flood tide and outgoing ebb tide to work on the turbine. However, development of tidal power causes problems to navigation and siltation. Since most tidal channels are used for navigation in Bangladesh, generation of electricity using tidal power will have to be limited in isolated channels inside the Sundarbans area. Solar power uses sun's energy to produce electricity. Solar energy is plentiful in Bangladesh. Generation of electricity using solar power is environmentally feasible. Development of solar power should be top priority for Bangladesh in the 21st century. However, most of these alternative sources of energy are still more costly compared to the energy produced by conventional methods. To meet the increasing demand of energy, Bangladesh should also consider developing nuclear power as the sources of future energy.

To meet the world's energy demand in the future, further research and development of the nuclear energy will continue throughout the world. Many countries in Europe heavily rely on nuclear energy. For example, France uses up to 75% of nuclear energy to meet the national demand. Germany, UK, USA, and Japan also use a tremendous amount of energy generated by nuclear reactors. Although nuclear energy is very efficient, it is relatively costly. There are some risks involved in safety procedures and disposal of waste materials generated in nuclear power plants. Occasional accidents can be dangerous. However, "media overreaction" and "enviroscare" against nuclear power plants certainly play a major role in mobilizing public opinion on this issue. Except for Chernobyl disaster, which was caused by a faulty and outdated technology in the former Soviet Union, and the Three Mile Island incidence in the USA, there hasn't been any significant accident associated with nuclear power generation. Any other sectors have risk associated with accidents. For example, the Bhopal disaster in 1984 was caused by a chemical industry (the Union Carbide), and was equally dangerous. In addition, the problem of radioactive waste disposal remains an unresolved issue. As far as the radioactive waste disposal is concerned (in the case of fission reactors), recent studies show that clay-rich seabeds can be used for disposal of such waste. The Bengal fan has one of the highest sedimentation rates in the world and could be a place for such burial (if we have to).

There are different kinds of nuclear reactors. The most efficient type is the "Breeder Reactor" which are not only efficient, but also relatively safer. In addition, the nuclear fusion reactors, as opposed to fission reactors, use heavy deuterium and tritium (a form of hydrogen) as a source of reaction. Fusion reactors produce water as by products--not radioactive waste (i.e. absolutely no environmental risk is associated with them). These fusion reactors are still in research stage, but significant strides have been made in development of these reactors. One gram of deuterium-tritium can generate energy equivalent to burning 45 barrels of oils! In addition, research is ongoing to develop cold fusion (i.e. at room temperature). These are all matters of future. We need to adopt a power generating technology that is economically feasible and environmentally sound. Bangladesh is not at the leading edge of technological research. This situation gives us an opportunity to learn from other people's mistakes. And with the current trend of globalization of trade and technology transfer it will be easier to adopt what is efficient and environmentally feasible for Bangladesh.

Clean air, water, and land are human right: 

All people have a right to a clean environment. Material wealth, such as the guarantee of food, employment, subsistence, education, and health, will not make human life worthwhile without having clean air, water, and land. To achieve this goal, Bangladesh needs to implement stricter laws to control solid waste, industrial waste, medical waste, and sewage sludge disposal. All municipalities need to have garbage collection services and sanitary landfills or incinerators to control solid waste disposal. In addition, implementation of sanitary toilets in all villages should be a primary requirement to keep both surface and groundwater clean. All chemical and liquid wastes need to be treated before disposing in rivers and streams as effluents. Recent incidences of ammonia contamination of rivers by the Ghorasal fertilizer factory, trace metal contamination of soils by the Hazaribagh tannery, arsenic contamination of millions of tube wells, and lead contamination of air will become catastrophic in proportion if no mitigation measures are taken. To reduce environmental degradation caused by point-sources of pollution (such as, industrial and medical sources of contamination), the "polluters-pay-policy" (PPP) must be implemented. Moreover, a better land management practice will be necessary to control non-point sources of contamination, such as arsenic, fertilizers, animal waste, detergent, and pesticides. These higher environmental standards will be costly to Bangladesh in the short term, but in the long term less costly than contending with more drastic environmental remediation and the destruction of major natural resources. These policies are often hard for elected politicians to sell to a population which is already faced with financial hardship. Only by educating the public on the need for immediate action, and on the connection between their survival and environmental stewardship will this be possible.

Effect of land-use is cumulative: 

Gradual degradation of the environment eventually will lead to catastrophic consequences. For example, every time we build a new house or a road on the floodplain, we reduce the total run-off area and groundwater recharge area, which result in an increase in flooding propensity or in decline in the groundwater table. Filling up of the lakes (e.g. the recent incidences of encroachment onto and land-grabbing of Gulshan-Baridhara lakes in Dhaka by the RAJUK) and rivers by dumping sediments for development reduces the water carrying capacity of a drainage network, causing water logging and extended flooding in an area. In order for us to be able to reduce the flooding propensity in Bangladesh, we have to control building on the floodplains. Also, deforestation due to development leads to increased soil erosion, decline in bio-diversity, increase in flooding, decline in groundwater recharge, and increase in carbon dioxide (a greenhouse gas) in the atmosphere. In Bangladesh, lateral spread of development should be contained as much as possible by implementing more environmentally-sound development, such as cluster housing and compact township. New development for housing, roads, shopping malls, or offices will have to be vertical, i.e. multi-storied. New laws and regulations need to be developed and strictly enforced to control lateral development onto the floodplains. Planners and developers must produce an environmental impact statement (EIS) for their planned land-use activities. The EIS should include alternative plans, as well as cost/benefit analysis, which should be reviewed by the general public and independent experts in the field before implementing.

Most environmental problems are related to Earth processes: 

Many environmental problems result from human interactions with natural processes, extent of which do not conform to political boundaries. Natural processes cannot be prevented. However, a comprehensive understanding of these processes can allow us to effectively plan land-use and thereby mitigate their effect. For example, flooding in Bangladesh is but a part of the overall hydrodynamic process that is active in the Ganges-Brahmaputra-Meghna watersheds. Bangladesh comprises only 10% of the watershed, and is located at the receiving end of this basin. Since Bangladesh is a small part of a bigger hydrodynamic system which consists of several countries in the region, a mutual understanding and cooperation among the co-riparian countries will be necessary in order to formulate any long-term and permanent solution to the flooding problems. Arsenic contamination of groundwater in Bangladesh is just another example of a geologic problem that owes its origin to areas beyond the confines of Bangladesh. Therefore, any clean up measures for these aquifers could be futile, since Bangladesh is located down-gradient of the geologic formations that contain water. However, further research may prove otherwise.

Multiple and aesthetic uses of land: 

Because of the scarcity of land, any land-use planning needs to be designed for more than one purpose, when and if possible. For example, a lake in a residential area can have multiple purposes: (a) water sports, (b) fishing, (c) groundwater recharge basin, (d) recreational park, and (e) flood control reservoir. Another such example can be the usage of dredged sand from rivers. The dredging of rivers can: (a) improve water transport, (b) reduce flooding propensity, (c) supply sand for building and road construction, and (d) supply sediments to elevate roads and villages, which in turn can reduce flood damage. In addition, dredged sands that are enriched with iron hydroxides (e.g. red sand from Barind Tract, Madhupur Ghar, and Brahmaputra-Tista basin areas) can be used as liners in ponds to reduce arsenic contamination in surface water. However, further research will be necessary to study the feasibility of such usage of red sands.

Recycle-Reuse-Reduce: 

This is the most fundamental slogan for environmental awareness. Most Bangladeshis recycle newspapers, aluminum utensils, and glass bottles. However, an integrated plan is needed for a nation-wide recycling plan for everything that is recyclable. Proper environmental education, workshops, training, and publicity can increase awareness about reduction in the use of commodities through the basic concept of recycle-reuse-reduce.

All species have the equal right to survive: according to the "Gaia Hypothesis" put forward by "Deep Ecologists", all flora and fauna are nature's creation and have an important role to play in the intriguing web of life. All species have an equal right to survival. Human activities have already driven many species from the surface of the earth. Only a few years ago most jungles in the villages of Bangladesh were rich in bio-diversity. For instance, hedgehogs, weasels, lizards, cheetahs, parrots, owls, etc. are now almost extinct. Stricter environmental laws and better awareness are necessary to save all species before they are extinct. This is primarily a result of loss of habitat. This issue will have to be addressed by setting aside sensitive parcels of land for bio-diversity and by encouraging the reclamation of certain habitats through reintroduction of the near-extinct species in those protected sanctuaries.

The star thrower: 

According to an American folk story, two friends were walking on the beach after a coastal storm that washed thousands of starfish ashore. As they walked, one of the friends started to pick up starfish one by one, and started to throw them in the water. The other friend says, " there are thousands of starfish on the beach, what difference will it make if you throw just a few in the water?" His friend picks up another starfish and says, "it will make a difference for this one" as he throws it in the water. All of us can be "a star thrower" even in a small way. Everyone can make a difference. Collectively, we will make a big difference.

Money is not edible: 

To summarize, nothing can be said more succinctly than what the Chief of Mohawk Red Indian Tribe said, "not until the last tree has fallen, the last river has been poisoned, the last fish has been caught, will man realize that money isn't edible." We need to act to preserve the only habitable planet before it is too late.

 

Can rainwater harvesting be a solution to drinking water problem in Bangladesh?

Md. Khalequzzaman, Assistant Professor of Geology, Georgia Southwestern State University, Americus, GA 31709, USA. URL: http://vulcan.gsw.peachnet.edu/khaleq

There is a common misconception among the villagers in Bangladesh that rainwater is pure. Since rain form by condensation of evaporated water (like a distillation process), it seems reasonable that rainwater would be of good quality. A myth about the purity of rainwater prevails even among many educated people. In fact, many quack doctors (I have seen one in our own village when I was a little boy) in Bangladesh use rainwater to substitute distilled water used in injections medicine in human body. Now that arsenic contamination of groundwater in Bangladesh poses serious threat to health, more and more people are turning to surface water sources. Rainwater harvesting offers a possible source of drinking water. Many agencies, including the Water and Sewerage Authority (WASA), are studying feasibility of rainwater harvesting in Bangladesh. The most important questions that need to be addressed before harvesting rainwater are: (1) is rainwater harvesting economically and technically feasible for rural people? and (2) does rainwater meet the quality for drinking water?

Amount of rainfall varies both spatially and temporally. While the maximum amount of average annual rainfall occurs in the northeastern districts (55 cm) of Sylhet and Moulivibazar, the minimum amount falls in the western/southwestern districts (15 cm) of Meherpur, Kushtia, Chuadanga, Chapai Nawabganj, Noagaon, and Rajshahi. Also, rainfall is mainly restricted during the months of April to September. Consequently, rainwater harvesting will be relatively easier during certain months of the year in the certain parts of Bangladesh. Groundwater contamination by arsenic is more severe in the western/southwestern districts, where rainwater harvesting would be more appropriate to solve the polluted drinking water problems. A 1982 study, by the United Nations Environment Program, showed that with an average rainfall of 72 inches and using 1,100-gallon storage tanks, enough water could be collected in 12 hours to serve a family of six for 45 days.

Rainwater harvesting -- in one form or another -- has been in practice for thousands of years. According to Paul Woods of Texas A & M University, extensive water harvesting systems in the Negev Deserts of Israel more than 2,000 years ago have been documented. Additionally, Roman villas and cities were planned in such a way to take advantage of rainwater for drinking and air-conditioning. Cisterns, containers to collect rainwater, were fairly common in the United States in rural areas until the 1920s. Rainwater harvesting requires an arrangement to collect, treat, and distribute the captured rainwater. The quality of rainwater harvesting technology varies widely depending on the availability of resources available. For example, a commercial company in Texas deploys sophisticated technology to collect, treat, and distribute captured rainwater. Villagers living on the rain-shadow areas of the Andes Mountains use a long and wide piece of thick cloth raised with long poles like sails of a boat to collect rainwater. Rooftops in buildings can be designed to collect rainwater, as is done in Kawranbazar office of the WASA. However, most buildings in Bangladesh are not designed for rainwater harvesting. Structural modification of buildings will be necessary to make them suitable for rainwater harvesting. Such an investment will be beyond the financial means of most families living in Bangladesh. In addition, millions of slum dwellers, who constitute the majority of the city population and who are in dire need of clean drinking water, will have difficulty to adopt such techniques to say the least. The situation in the villages is even worse as it pertains to rainwater harvesting. Although it will be financially burdensome, most tin-roofed houses can be modified to capture rainwater by adding a gutter system. However, most villagers living in houses made out of straws will not likely to have the means and resources to adopt such rainwater harvesting technique.

Next question is how to keep the rainwater for dry season? Saving rainwater in vessels for later use will be practically impossible, for it will require a huge number of such containers. Another possibility would be to dig ponds to gather rainwater for use during dry months. However, a series of problems will arise from such measure. First, there are not enough lands available in various parts of all villages in Bangladesh. Second, ponds will be subject to surface run-off that will carry different pollutants from non-point sources. Possible non-point sources of contamination include fertilizer, pesticides, chicken and cow manure, dissolved minerals, sediments, sewage, decaying plants, algae, bacteria, aerosol fallout, and detergents. The amount of surface run-off can be reduced by building elevated banks around ponds. Third, water will be lost to evaporation if the ponds are not completely covered. Fourth, ponds will be connected to groundwater flow and will be subject to contamination by dissolved chemicals. Most feasible option would be conjunctive and seasonal use of rainwater during wet months, and other sources of surface water and groundwater during dry months.

Studies of the chemical composition of rainfall have been carried on for many years starting in late 1880s in the United States and in Europe. Rainwater collected in various parts of the USA contains (in milligrams per liter): Fe (0.015) , Ca (0.075-1.41), Mg (0.027-1.2), Na (0.22-9.4), Ca (0.075-1.41), K (0.072-0.11), HCO3 (4-7), SO4 0.7-7.6), Cl (0.22-17), NO2 (0.02), NO3 (0.02-0.62), and Total Dissolved Solids 8.2-38), and pH of 4.9 to 6.4. Although most of these concentrations fall within the safe limit prescribed by the US Environmental Protection Agency, some exceed safe drinking water limit.

Rainwater in rural areas - away from atmospheric and industrial pollution - is fairly clean except for some dissolved gases it may pick up while traveling through the atmosphere. Some scientists consider rainwater as the "gold standard" of water. However, rainwater is not free of pollution. It contains most of the atmospheric gases in dissolved form in proportion to their abundance. In addition, rainwater contains sediments, dust, aerosols, particulates, and anthropogenic gases that result from industrial discharge, biomass and fossil fuel burning. Gases such as H2O, SO2, NH3, NO2, N2O, HCl, CO, and CO2 are produced in substantial amounts by burning of fuels, by metallurgical processes, and by other anthropogenic activities, and also by biochemical processes in soil and water. Carbonates, nitrates, and sulfates in the atmosphere can react with water vapor and form carbonic, nitric, and sulfuric acids, respectively. These acids washed down with rain and form acid rain, which is detrimental to ecosystem and water quality. Since rainwater is not pure water, some precautions will have to be taken before the water is consumed. Sediments will have to be removed, and water further purified by using a reverse osmosis distillation system. This is a membrane permeation process that separates pure water from a less pure solution containing dissolved chemicals. Rainwater purifying techniques also involves passing through a pipe surrounded by an ultraviolet light, which kills most pathogens. Based on the Texas Water Development Board's "Texas Guide to Rainwater Harvesting", a scientist named Krishna developed a rainwater harvesting system in 1998 and received approval from the city of Portland, Oregon, to use his system for all household use (http://www.rdrop.com/users/krishna/rainwatr.htm). The rainwater harvesting system costs less than $1,500 and consists of the following components: a 1500 gallon plastic cistern, a 1/2 horsepower shallow-well pump, plastic (outdoor PVC and indoor CPVC) piping, two particulate filters in series, rated at 20 and 5 micron particle sizes, an ultraviolet light sterilizer, screen covering the cistern, a 20 gallon water butyl rubber diaphragm pressure storage tank, and a reduced pressure backflow prevention device. The cost to install a similar system in Bangladesh will be much less, because indigenous equipment will be cheaper than buying from the United States.

Rainwater harvesting is in use in many parts of the world. There is a long established tradition of rainwater collection in some parts of Alaska and Hawaii. City of Austin, Texas, offers rebate for using rainwater for some household uses. According to the "Sourcebook Harvested Rainwater", in some areas of the Caribbean, new houses are required to have rainwater capture systems. Hawaii apparently is currently developing (or has already developed) guidelines. The island of Gibraltar has one of the largest rainwater collection systems in existence. Rainwater offers advantages in water quality for both irrigation and domestic use. Rainwater is naturally soft (unlike well water), contains almost no dissolved minerals or salts, is free of chemical treatment, and is a relatively reliable source of water for households. Rainwater collected and used on site can supplement or replace other sources of household water. Rainwater can be used as drinking water if proper treatment is done before using. McElveen, a physician from Texas, also developed methods to treat rainwater for drinking purposes. For drinking water treatment (http://twri.tamu.edu/twripubs/WtrSavrs/v3n2/article-1.html), McElveen relies on 5-micron and 1-micron cartridge filters and an ultraviolet (UV) treatment. He runs an Environmental Protection Agency test every 8 months for the same contaminants as municipal utilities test for: heavy metals, volatile organic compounds, pH, and hardness.

Bangladesh is faced with numerous water-related problems: flooding, droughts, arsenic contamination of groundwater, surface water pollution by point sources and non-point-sources of pollution. To solve these problems, Bangladesh will have to develop an integrated water resources development plan. Although rainwater harvesting will not be able to replace all other sources of drinking water, it will certainly be able to ease the pressure on surface water and contaminated groundwater usage as the primary source of drinking water. The development of a rainwater harvesting plan that is economically and technically feasible for the majority of the people in Bangladesh should be given high consideration as a part of the integrated water resources management plan.

 

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