India has a variety of problems, ranging from social to economic. The current environmental issues are: deforestation, soil erosion, overgrazing, desertification, air pollution from industrial effluents and vehicle emissions, water pollution from raw sewage and runoff of agricultural pesticides, tap water is not potable throughout the country, and the huge and rapidly growing population is overstraining natural resources (ODCI Gov. 1998). Calcutta, the capital of West Bengal has maintained an alternative treatment system with wastewater for many years. The people of West Bengal, have subsisted on their immediate resources for many years. One of their main resources, they have worked extensively and successfully with is "waste". This common sense approach has been particularly prosperous due to the ideal weather that Calcutta endures. I use the term "endures" rather appropriately I feel. Calcutta has a subtropical climate with their infamous seasonal monsoons. The temperature fluctuates from 44’F to about 108’F. This climate is obviously not ideal for human habitation, many crops however, thrive on it.

The city does not have the development, in the sewage system to deal with its overwhelming population problem. The city has relied on the wetlands to play a paramount role in the sewage treatment process. This wetland area has made aquaculture development thrive for this struggling country. India actually holds the seventh position in world marine fish production and is also one of the leading nations in marine products exporting (REI,1998). It has come to a point now, with the increase in population that even the sturdy wetlands are having a difficult time keeping up with society. The wetlands serve as a natural water purifier; they extract the nutrients from waste, resulting in clarified water. We’re not talking drinkable water, but purified to the extent of being considered "clean" or "treated". This water can then be utilized with and for other resources, and help the country in its’ economic prosperity. The solution that seems to make the most sense is the need for regulation on sewage and drainage to these precious wetlands.

Classifications of a wetland are as follows:

1) wetlands are distinguished by the presence of water

2) wetlands often have unique soils that differ from adjacent uplands

3) wetlands support vegetation adapted to the wet conditions (hydrophytes), and conversely are characterized by an absence of flooding-intolerant vegetation (Mitsch, 1986).

These intense weather conditions and the geographic lay out of Calcutta have endowed the city with rich natural resources. These resources give breath to sensitive and powerful wetlands.

Social Aspects

Calcutta, the capital of West Bengal State, is the site of India’s largest metropolitan area. The population of Calcutta is extremely dense. Historically speaking, we still see some major walls put up by the government. India has had the "Caste System" in place for many years. This system separates the community depending on what family they were born into. The problem with this system is, it has alienated a large portion of society. This large group of people that are considered "lesser than life" are considered to be the "untouchables". With the country literally ignoring such a large chunk of it’s own people, many problems come into play. The main problem is that of poverty.

Approximately 85,500 persons per square mile inhabit the bustling city (Calcutta: Physical and human geography, 1998). The city is located on the eastern bank of the Hooghly River. The Hooghly is an arm of the Ganges River, and flows directly into the Bay of Bengal. The Hooghly flows about 160 miles from Calcutta to the Bay of Bengal. This portion of the river is heavily industrialized. This portion of the rivers’ banks is also home to more than one-half of West Bengal’s population (Hooghly River, 1998).

Calcutta is a major educational and cultural center in India. There are two universities in Calcutta, which offer the chance at a higher education. There exist hundreds of languages spoken throughout India. Calcutta itself is home to the languages of Bengali, English, Hindi, and Urdu (Calcutta, BO 1998). The climate of West Bengal seems unbearable to a spoiled Southern Californian. The southern part is more of a tropical savanna, while the north is classified as humid subtropical. The average rainfall in Calcutta alone averages 65 inches per year. This is not a constant rainfall, but occurs with the majority falling in August (monsoon season) and a small amount falling in December. Average temperature at Calcutta is 81’F. You can find a dense coastal mangrove forest at the delta of the Hooghly, called Sundarbans. A large portion of this area has actually been set aside as a national park ("India: Northeast India: 1998). A mangrove forest is actually a type of wetland. Wetlands in general seem to thrive in the rich Indian climate.

The community utilizing the wetlands, have sustained the Calcutta wetland resource recovery system, as oral tradition. This is a low-tech and profitable way to treat water effectively. By oral tradition, I mean that this is a way the community has successfully utilized the land through generations teaching generations. This would be the same idea as artists or carpenters teaching their craft to their peers or children. Oral tradition is one of the main ways that India has operated in many aspects of "her" existence.

Many regulations have been put on wetland upkeep in this developing nation. The problem however seen again and again is that these regulations are not enforced. Without enforcement of these regulations the wetlands will surely cease in productiveness. Some of the reasoning of why regulations may not be so tight in India may exist in the economy. The government has its focus on feeding this third world country. The economy itself is a mixture of modern industries, traditional farming, handicrafts, and a multitude of support services. The startling statistic is that 40% of the population cannot even afford an adequate diet. The city also has a major housing shortage. About 1/3 of Calcutta live in bustees. Bustees are "a collection of huts standing on a plot of land of at least one-sixth of an acre", or we may know them as slums. The government does sponsor a bustee-improvement program (Calcutta: Physical and human geography, 1998).

Technical Aspects

The wetlands of West Bengal have served as a wonderful base for aquaculture to thrive in India. Aquaculture is the raising of marine or freshwater animals and plants in controlled environments. This form of farming has its advantage over terrestrial farming, namely:

• High Yields: Yields of plants, algae, fish or shellfish can be up to 10-100 times greater per acre per year than a terrestrial crop.
• Efficient feed conversion: Fish and shellfish can convert feed to flesh much more efficiently (e.g. 1.5:1 conversion ratios compared to 5:1 for hogs or 10:1 for cattle), primarily because they do not waste energy maintaining constant body temperature or supporting their weight against gravity.
• Use of non-farmable land: Aquatic species can be grown in lakes, bays, deserts or marginal land otherwise unusable for agriculture.
• Reduced Market Competition: The only major competition for aquatic foods is the fishing industry, which is economically depressed due to high costs of fuel and reduced fish stocks (Serfling, 1982).

In general sewage is usually a threat to the marine environment. Sewage contains harmful chemicals, disease-causing bacteria and viruses, and dissolved material and solid matter. Pipeline discharges, storm water run-off from streets, and commercial and industrial developments all attributes to sewage spouted directly into Calcutta’s wetlands. The presence of contaminants in wastewater is a direct threat to human health. Humans are exposed to pathogens through contaminated water and fish (Sea Grant News Media Center). The answer seems to lay in regulation. The government is aware of this problem; it just seems to be a matter of them dealing with it effectively.

Sewage should be treated before its disposal in a receiving watercourse. Particularly in hot climates, polluted water is a potential source of infection. Water should be treated in order to reduce the spread of communicable diseases caused by pathogenic organisms found in sewage. Surface and ground waters are also in jeopardy if polluted water goes untreated (Mara, 1976). In developing countries we see the reoccurring problem of wastewater treatment, sitting low on the governments’ "fix it" list. Most countries see wastewater treatment as a high expenditure. There are people who have brilliantly found ways around the money predicament. Biological, economic, and environmental benefits that accrue from recycling municipal and agroindustrial solid and liquid wastes are well recognized in India and abroad (Jhingran and Ghosh, 1990). India has used waste to their benefit since 1850. Since around 1960, brackish water aquaculture has made quite an impact (D.Ghosh, 1990).

Why doesn’t India use conventional mechanical sewage treatment plants? This method was actually attempted over the last fifty years. These plants have performed poorly in India with frequent breakdowns, and they usually end up abandoned. Some of the reasoning behind this could stem from improper operation and maintenance, and also the shortage of municipal funds to meet the high operational cost of such plants. Recycling wastewater makes much more sense for a country like India, or any country for that matter. Increasing attention is being given to recycling of wastewater through agriculture and aquaculture, mainly for two reasons:

• it ensures proper disposal of wastes after reducing their pollution load and,
• it increases resource utilization by relieving pressure on irrigation water and ensuring savings in costly chemical fertilizers (Ghosh, et al.)

Duncan Mara makes the point that the general scarcity of water in the tropics and subtropics and the high costs of developing new water supplies are the two major factors responsible for the increasing recognition of the need to conserve water resources. Conservation can be done by effluent re-use (e.g. for aquaculture or irrigation) or by effluent reclamation to produce water suitable for industry (e.g. cooling water) for drinking water. The wetlands in Calcutta have been designed to combine aquaculture and agriculture, and in the process leave its community with a clean environment. The basic way this works as far as agriculture is concerned is by creating sustainable gardens on landfills of pure garbage.

To understand part of how aquaculture works you need to know about wastewater treatment. The basic definition of water treatment is the manipulation of a water source to achieve a water quality that meets specified goals or standards set by the community through its regulatory agencies. More and more countries around the world are finding a problem with groundwater contamination, mostly by organic chemicals. Massive investments of resources to provide the world’s population with a satisfactory water supply are needed. When selecting what water treatment process to use, there are a couple of major determinants. These two major determinants are the nature of the water source and the intended use of the treated water (Wiley, 1985). Jingran and Ghosh summarize some of the treatment methods used in urban India in their 1990 article quite thoroughly. They are as follows:

1. Secondary treatment is used for the biological removal of organic materials. Three main methods are involved: activated sludge, trickling filter and waste stabilization pond.
2. Tertiary treatment for biological or chemical removal of soluble products of partial or complete oxidation.

The Water Aspect

Calcutta has worked the system so that city waste flows into long narrow ponds, or sometimes directly into the fishponds (Krishnamoorthi, 1990). Currently, there are more than 3000 ha of land being utilized for fisheries, in Calcutta alone (Ghosh, book). What basically occurs is the sewage flows into a pond and settles, or the sewage can flow directly into a pond where fish are being grown. This sewage actually encourages the growth of large quantities of algae and zooplankton. When such waters are fed to fishponds, the blooms of algae and large populations of worms and zooplankton become ideal fish foods (Krisnamoorthi, 1990). Calcutta actually stands alone, when it comes to using raw sewage directly in the fishponds, in place of fertilizer. One of the keys to keeping the fishponds productive is the maintenance of the loading rate of wastewater. You need to monitor the amount of wastewater so that the ponds remain aerobic throughout the day and night during the period of culture. Sometimes dilution is required; with freshwater containing a normal oxygen concentration; in order to keep a positive dissolved oxygen (DO) balance. The ideal water used in fishponds seems to be primary sewage. "Primary sewage contains less organic matter than raw sewage but more nutrients than secondary or tertiary sewage effluents and is generally more congenial to fish culture in ponds where no other fertilizer or supplementary feeds are given" (Jingran and Ghosh, 1990). Calcutta City sewage contains valuable nutrients itself, for plant growth. Studies done at Jadavpur University in 1983, actually revealed that metallic ion concentrations in the cities sewage was/is remarkably low (Patnaik, 1990). To see high production levels in a sewage-fed fishpond, two main things need to occur. One, is the flow of sewage must be regulated to keep the pond aerobic. The other important task is effective fertilization of the fishpond using sewage as organic manure to stimulate natural food production as feed for the fish.

Maintaining the Pond

It would be nice to be able to dig a hole, throw some sewage in, and watch a community of fish grow and thrive. It does take a little more effort though. Ideally pond preparation is carried out during the cooler months. "This involves complete draining of the pond; desilting of the silt traps; tilling the pond bottom; and dike repairing activities" (D.Ghosh, 1990). In February primary fertilization takes place, when wastewater is added to the pond and allowed to undergo natural purification. The water is stirred well, before any fish are added. This stirring of the water helps keep the water aerobic, so organisms can develop for the fish to feed upon. The addition of the fish actually takes place around the middle of March. Usually small amounts of fish are added first, somewhat like "guinea pigs" to test the water and insure that it’s livable. Fish are usually stocked about four times a year. There are periodic inputs of wastewater into the ponds throughout the growth cycle, which is known as, secondary fertilization. This secondary fertilization helps the pond maintain a healthy plankton growth. The main thing to recognize, is that DO concentrations do not fall to the extent that fishes die (D.Ghosh, 1990).

Water hyacinths (Eichhornia crassipes) are used quite often in these ponds for the removal of impurities. Studies have shown that these beautiful, not to mention hardy plants, absorb large amounts of nutrients and trace organic substances from water (A.Ghosh, et al, 1990). This floating aquatic plant proves itself useful in a variety of other ways as well. Water hyacinth breaks the surface waves that would otherwise erode the banks of the ponds. These plants are used in place of costly manmade materials such as bricks, or concrete. Fish enjoy the shade that these floating plants provide on hot summer days. When the plants are done serving their purpose in the fishponds, they can be used as animal feed, or even decomposed and used for feed in the fishpond (D.Ghosh, 1990).

Another trick that has attributed to the success of many fishponds is the removal of silt. "This removal process improves the habitat, preventing the creation of a toxic zone which could endanger fish life", as stated by Patnaik in his 1990 article. Silt accumulates in silt traps, which are 3m wide, 30-40 cm deep borrow pits around the fishpond. What happens is that the fishponds are flat and when the fish are netted, the bottom deposits are dragged into these pits. This helps the sedimentation from stirring up through out the whole water column (D.Ghosh, 1990).

Fish Life

One of the main attributes of wastewater recycling through fishponds is the economic profit they provide. Sewage fed fishponds provide 8,000 t/yr. or 11.4% of the total supply of fish for India. The amazing thing when looking at the economic aspects is that the entire ecosystem has been built without any external financial help. The money earned from the sale of fish has given a gross per capita income of about $4.00 a day, which is more than three times the minimum daily agriculture wage in India (D.Ghosh, book). "Three species of indigenous carp, three species of exotic carps, and the tilapia form the major cultured species in the sewage-fed fishponds" as noted by Patnaik. Fish to be reared in waste-fed ponds should have the following characteristics (as noted by Polprasert)

1. tolerant to low DO level which can occur during the night or at dawn when photosynthetic oxygen production does not occur;
2. herbivores or omnivorous in nature to feed on the waste-grown phytoplankton; and
3. tolerant to disease and other adverse environmental conditions.

After the Ponds

What do we do with the water after the fish are cultivated? One thing that we can do with the effluent from the wastewater-fed fishponds is utilize it to grow non-monsoon paddy rice. This downstream resource recovery practice in which fishpond effluent is used to irrigate paddy fields is a recent innovation in comparison to garbage vegetable gardens and wastewater-fed fishponds. One of the benefits to this process, is you have much less of a chance of any health risks from using this process then you do when using raw sewage for agriculture (D.Ghosh, 1990). Not only does the fishpond system work in the productive cultivation of food, but it also helps the environment in Calcutta. The water that is now going out into the land or other rivers has been treated to the point of "clean". Not bad for a low tech, low budget, indigenous system.

Problems

Governmental Issues

When we address the topic of problems pertaining to the wetland system in India, we need to recognize a couple of major issues. One of the first issues is the government or regulation problem. India has meant to "do well" for it’s country time and again. However remedies to major problems never seem to happen. This is evident to the world, when we see the caste system that India has placed within the infrastructure of its immense society. To be entering into the 21^st century, with an enormous amount of "untouchables" is ludicrous. The country needs to recognize its entire people as one. It’s disheartening to me, that Mahatma Gandhi didn’t make more of an impact on his people. The problem with regulations in direct contact with the wetland system is frustrating at best. Laws will be set, but they won’t be enforced. Many brilliant ideas have come forward for the maintenance and improvement of the wetland systems, but they have not been implemented. The government has its focus in other directions it seems.

Another problem is that there are too many different agencies trying to coordinate the ponds, and they’re being neglected. The Department of Fisheries, the Department of Agriculture, the Department of Irrigation and Waterways, the Calcutta Metropolitan Development Authority, Zilla Parishad Panchayats (District Councils) and others are all trying to keep things running (D.Ghosh, 1990). You would think that with all of these people on a project that things would get done. They don’t seem to be working efficiently at all. The evidence can be seen in the shape the wetland system is in now.

Technology

There still is a major problem in India with the waste treatment systems they have in place. There’s an urgent need in India to develop appropriate technologies for treatment, disposal and reuse of human, animal and agroindustrial wastes. Though sewage disposal is viewed as more of an urban problem, its reuse for productive purposes can only be taken up in an organized manner in a rural area where suitable land is available for aquacultural and agricultural activities at reasonable cost (Jhingran and A.Ghosh, 1990). Technology needs to be given a boost. It seems that India has the knowledge to make improvements, it's just a matter of realizing the importance of this problem. Even if wetlands are not used for treatment, the country needs to make large improvements on the sewage system. Their precious rivers will soon be polluted beyond repair. Even more importantly, the people of India will not have reliable water sources.

The Calcutta fishponds that exist today have been greatly neglected. They are in need of a major "face lift". The fact is that no desludging has been carried out for the last 40 years because of resource constraints and lack of security of land tenure of fish farmers. This desludging needs to take place in order to keep these sensitive ponds balanced "nutrient" wise. Another extremely helpful job that needs to be done is the diversion of the total amount of city sewage to these fishponds. This will help increase the productivity of the ponds. Another necessary undertaking is to implement an adequate drainage system for all of the fishponds. This will help insure the health of the fishponds as well (A.K. Patnaik). The cost of these projects is anything but small, and financial needs will have to be met in order for these complex projects to move forward. Without an improvement of technology, India’s future will forever remain "third world".

 Health Problems

Aquaculture, using domestic sewage, may present some health problems to be aware of. The problem is that fish may carry human pathogens passively in or on their bodies and these pathogens may subsequently pose health hazards to fish handlers and also consumers. Wastewater is likely to carry considerable amounts of intestinal pathogens that may be transmitted to the fish. Another health hazard associated with this type of fish farming is transmission of parasitic worms through the intermediate fish host. This parasitic worm risk is especially a problem when raw sewage is utilized. It seems that with pretreated wastewater the eggs of these parasites have generally settled down and infections are minimal (A.Ghosh et al, 1990). The fish consumer is not at too much risk, as long as the fish is cooked well, and not eaten raw. The transmission of a pathogen from a fish to a human has not been documented in India. Studies should still be conducted, to assure that the public health aspects of sewage recycling are appropriately being met – such as proper pretreatment and engineering design of wastewater-fed ponds (Jhingran and A.Ghosh, 1990). Detergents and pesticides have also become public health problems. The pesticides eldrin and endrin, that are washed off nearby rice fields into fishponds have been reported to accumulate as residues in fish tissues. This is another indication that further studies need to be conducted.

 Opportunities

Where are the answers? To me, it seems that there are some extremely plausible remedies, to most of these problems. When we were addressing the governmental issues, the major problem was implementing the regulations. The solution may be to set up a separate coordinating agency that can oversee all of these agencies, so that the job gets done. The Ganga Action Plan, which is a plan enacted to clean up the sacred river, is an example of an effective program. Another idea that would help the extremely polluted river is to try and divert the urban sewage flow far inland from the river bank to accelerate its hygienic disposal through reuse (Jhingran and A.Ghosh, 1990). A problem with this is that, requirements for sewage in brackishwater aquaculture, both quantitative and qualitative, are poorly understood and a study will be needed before a comprehensive planning of resource recovery can be completed (D.Ghosh, 1990). Extensive studying needs to be done on the wastewater treatment systems in general for India. If India is able to efficiently run their wastewater treatment ponds; they will for sure be an example to the world. "They could lead the way to alternatives in low-cost sanitation technology and the wetlands could become an international demonstration center for training and research in this field", as Ghosh boldly stated in 1990. Rybczynski et al stated in 1978, "the universal solution of conventional sewage treatment plants does not reach more than 6.5% of the people in developing countries and that reuse of excreta in fish culture, algal and aquatic plant production and biogas production are promising technologies that may radically change the context of urban sanitation".

Conclusion

Great opportunities lay ahead of Calcutta, if the government and people are able to recognize what they have sitting beneath their feet. The benefits of aquaculture, or better yet utilizing waste to attribute to aquacultures’ success, is too amazing to look past. We have exhausted many of our resources on earth. The resources we think we have left, are quickly deteriorating before our very eyes. I believe the only answer can be found in sustainable agriculture and thus incorporating aquaculture. India is close to being a small example of the possibilities in this sustainable realm. One of the main problems for India becoming a flagship for this cultivation is the governmental priorities. It seems that the government now in 1998, would rather focus on nuclear weapons rather than on it’s crying poor. The unfortunate truth is that this can not go on for very much longer. There needs to be some major changes in the politics of India in order for the country to prosper in any way. They can’t rely on a few individuals to pull the country to the top. In my view, the country needs to pull together before they can go any further. It’s past time for change in India. The rest of the world is starting to think "globally", and India still can’t seem to think "locally".

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