Exploring Approaches to Fresh Water Storage and Uses for Irrigation in the Salinized Southwest Coastal Regions of Bangladesh

Hamidul Huq1 and Khalid Md. Bahauddin1

 

1 Institute of Development Studies and Sustainability (IDSS), United International University (UIU), Dhaka, Bangladesh; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it This e-mail address is being protected from spambots. You need JavaScript enabled to view it

 

Abstract

The agricultural system in the coastal regions of Bangladesh is heavily dependent on environmental factors such as timing, intensity and distribution of the monsoon, soil salinity and the availability of fresh water for irrigation. This study explores and documents farmers' practices and innovative approaches to fresh water storage and uses in agriculture and irrigation in the coastal regions of Bangladesh. The study is mostly qualitative in nature but some quantitative primary data were collected based on the study objectives. Primary data were collected through in-depth individual interviews, group discussions, focused group discussions and key informant interviews. The data collection for this study was carried out in the Bajua and Laodob unions of Dacope Upazila of Khulna District. This study found that the economic mainstay of the study areas is agriculture (51.67% for the Bajua and 50.43% for the Laodob union) and the bulk of the local population is dependent on farming. The study found that in 2009 a collective effort was made by the villagers, local political leaders and different NGOs in an attempt to stop shrimp farming in the study areas. These areas are now affected by severe water scarcity problems and due to a lack of water sources and increasing salinity, the people in the study areas cultivate rice (Aman) once a year, and more recently, rabi crops during the summer season. Farmers depend mainly on rainwater, canals, ponds and rivers. It was noted that groundwater for irrigation using a deep tube wall failed in the study areas because groundwater levels had severely dropped. This study explores how increasing salinity, lack of water sources, rising temperatures and, recurring weather extremes are impacting agriculture, intensifying the vicious cycle of hunger and poverty which are becoming more frequent, especially during the summer season. It is interesting to note that farmers in the study areas dig small ponds alongside agricultural land, during the rainy season, for storing fresh water which is used for irrigating rabi crops in the summer season when soil salinity increases and water in the canal and river becomes silted. This study reveals that due to the high salinity of the groundwater and surface water, people in the study areas collect rainwater during the rainy season and store it for use during the dry season. However, within a short period, insects begin to breed in the water causing nuisance which affects the quality of the water being used for irrigation and drinking. In order to prevent this from happening, some people keep two or three Kai fish (Climbing Perch) in the water container to eat the insects and keep the water clean and free of nuisances. This study also importantly notes that, in order to keep the stored rainwater free from any nuisances, some people in the study areas apply a paste made from two or three pieces of raw turmeric wrapped in a clean cloth into the water container which is used as a herbal repellant that keeps stored rainwater free of pollution. Communities have developed these practices out of necessity, and even though these practices have not been scientifically tested, people believe in their efficacy.

Keywords: Water Storage and Uses, Irrigation, Practice, Coastal Bangladesh.

Introduction

 

The natural resources of the coastal zone of Bangladesh are very different from their terrestrial counterparts and require different and special forms of management. Coastal areas are important ecologically, as they provide a number of environmental goods and services. They frequently include critical terrestrial and aquatic habitats, such as mangrove forests, wetlands and tidal flats. Another special feature of the coastal zone is its vulnerability to multiple natural threats such as periodic cyclone and storm surges, salinity intrusion, erosion, pollution, and the overall lack of physical infrastructure. Coastal natural-resources primarily reflect subsistence agriculture with an emphasis on food production, e.g., paddies alongside cash crops and coastal fisheries, which provide a major food and income source (Islam et al, 2004). The southwest coastal region of Bangladesh belongs principally to the agro-ecological zone of the Ganges Tidal Floodplain. The tidal floodplain has an almost level landscape crossed by innumerable, often interconnecting, tidal rivers and creeks. Differences in elevation between river banks and basin centers are usually about 1 meter. The landscape is almost entirely comprised of clay soils. The rivers of this region are characterized by active deposition of sediment causing a significant reduction in their drainage capacity (Shampa et al, 2012). Under natural conditions, the land is subject to flooding with silty water at high tides. Tidal water is saline throughout the year. The region is part of an inactive delta of large Himalayan rivers and is protected from tidal surges by the Sundarban mangrove forest. Rainfall, river flow and tidal water are the major sources of surface water in the southwest region of Bangladesh.

Water systems in the southwest region are embedded in tidal rivers, tidal basins and beels. A beel is a natural depression. Bangladesh is a deltaic country where land in the plains has been formed by sediments carried down by the Ganges, Brahmaputra and Meghna river systems. Depressions are formed by numerous occurrences such as: subsidence of top soil caused by the creation of a vacuum below the surface caused by decomposition of organic substances mixed with silt; subsidence by tectonic movement; or floods which deposit sediment close to the river bank. The low lying land between two rivers is also known as a beel (Dasgupta S et al, 2016). A tidal basin is a depressed low lying area or beel adjacent to the sediment-laden tidal rivers. In the southwest region of Bangladesh there are several tidal basins which are very useful for sediment management of sediment-laden tidal rivers (Khanom T, 2016). The southwest coastal region has been identified as one of the areas in the world most vulnerable to the effects of rising sea levels level caused by climate change. It is estimated that the sea level in the region has been rising by 3-4 mm per year for last 30 years.

Increasing salinity has been one of the major problems for traditional agricultural practices in coastal Bangladesh for several decades (Rahman et al 2011). "We did not have saline soil and water in our tube wells and ponds before 1975. Salinity started to increase after the introduction of shrimp farming and the Farakka Barrage. Another reason is that people use saline water from the river in their shrimp gher (pond) and sometimes add extra salt to increase the water salinity. As the river and tube well water is very salty we cannot drink it, and have to use deep tube well water" (Brammer, 2014).

Once shrimp cultivation starts, the remaining trees and vegetation also disappear fast because of high salinity and inundation. Sometimes, trees remained longer on the dykes and embankments, but they also disappeared over time due to seepage of saline water. Reeds and grasses that are used for fuel or for making mats are gradually lost due to increased salinity levels in the waterlogged areas. The number of cultivated species of winter vegetables has declined from 1975 to 2006 in all the study areas (Hussain, M.G. and Hoq, M.E, 2012). In the winter season the farmers were busy cultivating rice, instead of vegetables. As they were subsistence farmers both women and men were engaged in rice cultivation, leaving little time to crop winter vegetables. One farmer stated: "People usually don't grow winter vegetables due to high levels of salinity in the vegetable growing season". Summer vegetables (kharif vegetables) were grown from March to October. The summer vegetables eggplant (S. melongena L.), white pumpkin (Benincasa hispida Thunb.), water spinach (Ipomaea aquatica Forssk.), lau (Lagenaria siceraria (Molina) Standl.), elephant foot yam (Amorphophallus campanulatus Roxb.), and cucumber (Cucumis sativus L.) were abundant in the study areas in 1975, but in 2006 they were rare or absent (Islam M.M et al, 2016).

 

Water for Agriculture

Increasing salinity, among other factors contributing to low quality irrigation water, reduced the crop yield to the extent that farmers lost interest in cultivating agricultural crops. Growth of rice plants decreases with increased salinity in irrigation water. The groundwater in the southwest region of Bangladesh is highly affected by salinity and sodium and continuous use of such irrigation water results in high sodium concentrations which break down the soil structure and reduce soil aeration and water infiltration (Murshed-e-Jahan et al 2014). For most farmers, rain water is the only source of irrigation for Aman rice cultivation. Heavy rain is required to flush out soil salinity at the beginning of the rainy season. But, in recent years the rainfall pattern has changed. Rainfall has become erratic and there is a decreasing pattern of rain in the early monsoon which harms agriculture. The amount of rainfall is decreasing, particularly in the pre monsoon and monsoon period (Islam, M.S, 2013). The canal, which used to carry fresh and a little saline water in the past, can no longer be utilized for irrigation purposes because of its salinity. Pond water, which was once used for irrigation purposes has also become saline and unsuitable for agriculture. Additionally, the ponds and the canal are being leased out to politically powerful people and utilized for intensive fish cultivation, therefore, prohibiting its use for other purposes. Since the fresh water table is deep and installing a deep tube well is costly, most farmers cannot afford to utilize ground water for irrigation (Abdullah, A. N et al 2016).

In the last thirty years salinity intrusion has degraded soil quality to the extent that some farmers cannot grow agricultural crops (Adnan, S, 2013). Due to lack of sufficient surface water during the dry season, 75% of the water used for irrigation is groundwater. The excessive amount of water pumped up from the Bangladeshi aquifer in relation to the amount recharging it increases salt water intrusion into freshwater aquifers (Hossain, M. S et al 2016). New changes in land and water use in the southwest region were made again in the late 1980s through innovation, development and practices of 'rice-prawn gher' farming using fresh water (mainly rainwater), which is a new local agricultural system solely innovated by farmers in the southwest coastal region since the mid-1980s (Ali, A. M. S, 2012).

For rice-prawn farming the farmers make perimeter-dykes, which is a modified rice field with high wide dikes and a canal inside the periphery of the dikes that retains water during the dry season. In addition to rice and prawn, farmers grow vegetables and fruit trees on the gher banks. The life cycle of prawn and carp is from May/June to December/January, Boro paddy is cultivated from the end of January to end of April and seasonal vegetables are grown throughout the year. Almost every year prior to the release of prawn post larvae (PL) into the gher, farmers repair the gher dikes and trenches. They use lime (30-40 Kgs per hectare) during gher preparation to reduce soil acidity. Traditionally, only snail meat was used as prawn feed, but nowadays in addition to snail, farmers use a wide range of homemade and commercial supplementary feeds. Usually, no specific supplementary feeds are provided for fish. Fish share the feed supplied for prawn cultivation. In general, the gher farmers do not use any type of organic fertilizer for Boro paddy cultivation as the remains of the feed nutrients that the farmers put in the gher during prawn and carp fish production supplement paddy field fertility. The farmers usually grow vegetables both during winter and summer seasons on the dikes (Barmon et al, 2004).

The rice-prawn gher sector offers diverse livelihood opportunities for the rural poor. A range of associated groups involved in this sector include prawn farmers, wild postlarvae collectors, fry traders, snail harvesters, feed traders, prawn traders and day laborers including women and children. The opportunities for day laborers to find work have increased significantly (Ahmed et al, 2008). Livestock and poultry in rice-prawn gher farming areas have increased. Prior to rice-prawn gher farming, landlords or rich farmers had large numbers of cows and buffalo and hired local boys to take care of the cows but most of the small, landless and marginal landowners had no cows or sometimes just a few. Now, it is possible for people to rear more than two or three cows for milk and cow-dung. Despite the unavailability of grazing fields, the gher farm owners and even landless farmers collect feed (grass) from the embankments and store by-product of paddy (straw) for cattle feed. The farmers use the stored straw in the rainy season when feed is not available (Ahsan D, Brandt US, 2016).

 

Objectives of the Study

Farmers' innovative practices in fresh water uses, storage and irrigation are common, but are small scale and scattered. If these innovations are scientifically documented, then this knowledge can be applied on a larger scale in the entire southwest coastal region of Bangladesh. The uses of local innovative approaches to fresh water storage and irrigation are also relevant to climate change adaptation of coastal agriculture. Scientific documentation of these practices is expected to generate effective contributions in sharing such knowledge with relevant stakeholders towards advocacy for science – policy interface. Considering the discussion above, the main objective of this study was to explore and document farmer practices and innovative approaches to fresh water storage and uses in the agriculture and irrigation in the coastal regions of Bangladesh.

 

Methodology

This study is mostly qualitative in nature but some quantitative primary data were also collected to meet the study objectives. Primary data were collected through in-depth individual interviews, group discussions, focused group discussions and key informant interviews with farmers, women; government and NGO field workers with relevant projects. The data collection for this study was carried out in the Bajua and Laodob union of Dacope Upazila of Khulna District. The study areas were selected specifically based on consultation with relevant stakeholders. For purposes of achieving the objectives of this research, six in-depth individual interviews, two key informant interviews, four group discussions and six focused group discussions in each of these two study unions of the Dacope Union of Khulna District were conducted using a set of checklists and guidelines. Secondary data will be examined critically and organized to obtain an in-depth understanding of irrigation practices and gender dynamics in water management in the study areas.

 

fig01
Figure 1: The selected study areas.

 

Findings of the Study

Major Economic Activities in the Study Areas

Since irrigation practices and water management were the focus of this study, it was reasonable to investigate the principal economic activities of the people in the Bajua and Laodob union study areas of the Dacope Upazila of Khulna District.

The economic mainstay of the Bajua and Laodob union study areas is agriculture and the majority of the local population is dependent on farming. The results of the 2011 Census show the majority of the people in the study area to be involved in agricultural activities for their livelihood. Table-1 shows that a great majority of the people (51.67% for the Bajua and 50.43% for the Laodob union) depend on agriculture. The data of this study indicates that these areas are predominantly inhabited by agricultural communities. This was further reinforced when researchers found that a preponderant majority of their fathers and grandfathers were also farmers. Although, agriculture is predominant in both the people of the study areas, there are other occupations represented as well. Other important occupations among the study groups were day labor and fishing.

 

tab01

 

It is noted that many people who are involved in agricultural activities such as farming are also involved in fishing, and many fishermen have small plots of land and a well for growing some Aman paddy and rabi crops. As many as 41.40 percent of the inhabitants make their living from day labor. This study revealed that these people were previously involved in agricultural activities but they had to change their occupation due to economic and environmental factors. This study found that fishing is an important occupation for the inhabitants in the study areas. Although the research team involved in this study does not have any specific data on subsidiary occupations of the study groups, it is quite certain that they must be engaged in some some other subsidiary occupations The saline water and severe lack of freshwater sources does not allow for multiple cultivation of different varieties of paddy on their agricultural lands. Cultivation, therefore, is very limited and farmers have nothing to do throughout some seasons of the year. It is therefore, quite logical for them to seek out other supplementary subsistence strategies. Apart from annual rice cultivation, the inhabitants of the study areas also started growing rabi crops, three of which are cultivated in abundance - watermelon, pumpkin and sweet potato.

 

Entering into Rice Cultivation from Shrimp Farming: Looking at the History of Stopping Shrimp Farming

Although certain types of economic development activities are beneficial for the macro economy and capital flow to relatively depressed regions such as southwest Bangladesh, shrimp farming has adversely affected the Bajua and Laodob union of the Dacope Upazila of Khulna. It was in 2007 that the people of the Bajua and Laodob union realized that the rapid development of shrimp farming was resulting in a series of negative environmental and social consequences in their areas. Actually the movement of stopping shrimp farming started in 2007 initiated by local political leaders and some villagers. They convinced people that the local shrimp farming led to a reduction in agricultural productivity and the availability of potable water. While it was enhancing foreign exchange through exports, it created loss of land, food insecurity and social dislocation.

Most of the farmers in the study areas indicated that, "before 2007, saltwater intrusion and chemical pollution associated with shrimp aquaculture resulted in irreversible changes in the soil composition of agricultural lands and surrounding areas and reduced productivity of the agricultural soil and rendered it infertile". In addition, most of the inhabitants in the study noted that rice production declined significantly in these areas due to salt water encroachment from shrimp pond canals traversing the rice fields. The inhabitants in the study areas expressed, "the high salinity of the soil in our areas prohibited cultivation of vegetables, destroyed those that serve as cattle fodder thus contributing to mortality of the livestock and reduced availability of dairy and meat". It is observed that in the study areas, prior to 2007 the degradation of agricultural land was usually followed by a further expansion of the shrimp farming industries. Poor landowners affected by the salinity of the water and land did not find crop and livestock production to be viable and often had little or no option but to sell their fields at deflated prices to aquaculture operators or to turn to shrimp aquaculture themselves. In addition, shrimp farming reduced social security and enhanced conflict in the study areas. Politically and financially strong farmers exploited small farmers and marginal farmers. Marginal farmers and small farmers had to sell their farmland at very low prices. Sometimes politically strong farmers captured neighboring farmland without any compensation.

This study revealed that prior to 2007, high salinity due to extensive shrimp farming negatively affected the health and wellbeing of inhabitants in the study areas. Salinization of freshwater for shrimp farming destroyed the sources of fresh water required for agriculture, livestock, drinking and household uses and other purposes. This study importantly noted that the lack of fresh water affected people in the study areas especially women and girls who are responsible for fetching drinking water from long distances which required two to three hours per day as nearby fresh water sources were affected by salinity, and this long distance of walking everyday affected their physical and mental health. Most importantly this study found that people in the study areas had to drink saline water due to scarce sources of fresh water resulting in different waterborne diseases. In addition, this study noted that drinking saline water during pregnancy caused hypertension resulting in assorted undesirable maternal and fetal outcomes.

Most of the people in the study areas said, "due to extensive shrimp farming prior to 2007, we saw the gradual disappearance of different grasses, vegetables, fruit and woody trees in our areas. It declined fodder sources and increased mortality rates of livestock. The reduction of animal feed and the pollution and salinization of water supplies due to shrimp farming led to an increase in livestock mortality in shrimp farming areas". This study revealed that rice production in the study areas decreased by 68 percent between 1985 and 2005 due to extensive shrimp farming which led to food insecurity among the villagers of the study areas and affected the livelihoods of the people who were dependent on agriculture. On the other hand, the people in the study areas noted, "increased salinity due to extensive shrimp farming significantly reduced our production of agriculture through lack of freshwater and dilapidation of the soil quality". The people in the study areas cited, "prior to 2007, unplanned shrimp farming caused enormous water-logging in our areas which extended from agricultural land to residential areas resulting in great numbers of people being forced to flee their homes and take shelter in school or government buildings. In addition, this reduced soil fertility for agricultural production, reduced opportunities for freshwater irrigation and created scarcity of fresh drinking water in the villages".

While substantial economic benefits were the main rationale for the increase in commercial saltwater shrimp farming, it is predominantly the external leaseholders and big local shrimp farmers who have gained economic benefits. The small landowners converted agricultural land into shrimp ponds or lease their lands to the owners of the shrimp farms (large landholders of the village or outsiders, and often alliances between two parties) since they are trapped by surrounding shrimp ponds. In some cases, socially and politically influential and wealthy shrimp farmers purposefully inundate large areas of agricultural land with saline water when they fail to take lease of agricultural land from small and marginal farmers. Nevertheless, as these farmers no longer had the option to cultivate rice they needed to lease their paddy lands to the influential shrimp farmers who also set the lease conditions..

Therefore considering all pros and cons, local people with their political leaders and NGOs in the Bajua and Laodob unions raised their voices against the social and environmental problems caused by shrimp aquaculture and took the revolutionary decision to stop this type of farming in which they finally succeeded in 2009 in spite of being faced with enormous internal and external political pressures and influences.

 

Exploring the Challenges of Irrigation and Farmer's Practices to Fresh Water Storage and Uses for Irrigation under the Adverse Environmental Condition

It has been more than eight years since shrimp farming has stopped in the study areas, i.e. Bajua and Laodob union of the Dacope Upazila of, Khulna District. These areas are now affected by severe water scarcity problems for agricultural production and a sustainable livelihood. As a result, the inhabitants in the study areas cultivate rice once a year, but now produce rabi crops in the summer season. When people started growing more crops year-round, they were faced with an even greater water scarcity problem. Most crops needed more irrigation water for production. Water is therefore a vital factor for high yields. Farmers depend mainly on rainwater, canals, ponds and rivers. It is noted that groundwater for irrigation use deep wells in the study areas because groundwater lever has already depleted. In the locality of the study areas, 15 to 20 years earlier, people used to store water traditionally in what they called Kua and Indara. They stored groundwater in the Kua which was a small deep hole (5ft - 10 ft) which was prepared of mud. But people were unable to use it for long periods of time due to inadequate groundwater. To cope with the situation, the people in the study areas started storing water in, what is locally known as, Indaras prepared of concrete rings with a depth of 15ft-20ft and after few years of using this, they had to discontinue their use due to an even further drop in groundwater levels. Now, the main problem of the study areas is the serious lack of water resources.

In the study areas, most of the people are dependent on agriculture. Agricultural practices in the Bajua and Laodob union are dependent on variations in environmental and climatic conditions. In these areas, Aman paddy is the main rain-fed crop. It is noted that the overall agricultural productivity in the study areas is now very low mostly due to unavailability of irrigation facilities, inadequate rainfall, siltation of ponds and canals and, less water flow in the rivers. Based on water sources and irrigation practices, the people in the study areas cultivate the following two types of crops each year:

 

tab02

 

This study found that all the farmers in the study areas depend on rain water for irrigating Aman paddy but sometimes rain does not occurs adequately which hampers the irrigation. In this case, the people of the study areas have to collect water for irrigation from canals and ponds by pumping or/and using laborers. All the farmers reported that this process is very expensive and some farmers could not able to afford this.

This process is also repeated in the summer season during the rabi period which is much more expensive than the Aman season. It is reported that if farmers use machines for pumping water from canals and ponds, it costs approximately BDT. 70 per hour but if they use laborers, it costs approximately BDT. for five hours. It was observed that in certain locations within the study areas both Aman and rabi crops were totally damaged due to an severe lack of irrigation water.

This study concluded that life is not effortless in the villages of Bajua and Laodob union. Levels of food insecurity in the study areas are highly evidenced in the summer season. Most of the people in the study areas are vastly dependent on agriculture but increasing salinity, lack of water resources, rising temperatures, recurrent weather extremes are negatively impacting agriculture therefore intensifying the vicious cycle of hunger and poverty which are becoming more frequent especially during the summer season. The increasing salinity, seasonal droughts and intense lack of water sources are frequent occurrences which greatly affect the people of the Bajua and Laodob union. These events are more pronounced during the summer season during which inhabitants are unable to cultivate any crops other than Aman, making them completely reliant upon the Aman crop throughout the entire year resulting in food and livelihood insecurity

In 1990, some people in Kocha village of Bajua union tried to cultivate watermelon in the summer season when there was high salinity in the soil and water and a lack of irrigation water. And they succeeded and found that watermelon is a good fit with the saline environment and requires low amounts of water. Then they cultivated pumpkin and sweet potato which were both successful during the summer season with increased salinity. This practice emerged as an epitome of success and now more than 90 percent of the people in the study areas follow this practice in the summer season securing their life and livelihood. This is not only a source of income during lean periods, but also provides food security for the farmer's family. It was observed that irrigation for watermelon is done carrying water in pitchers or buckets. In the initial months of cropping, surface water such as ponds and canals available in the water channels created by receding rivers are used. This innovative practice in the saline environment is a clear example of how a simple technology can build a communities' resilience to climatic extremes. This study recommends the replication of this innovative practice which requires low economic cost, making it highly desirable in areas with increasing soil water salinity and water scarcity.

This study also revealed that the farmers collect irrigation water from canals and nearest ponds through pipes. It is interestingly noted that the farmers in the study areas dig small/mini ponds adjacent to agricultural land during the rainy season for storing fresh water which is used in the summer season for irrigating rabi crops because salinity increases in soil and water and canals and rivers become silted during the summer season when rabi crops are planted. Farmers are also using the mini-ponds for fish cultivation and planting vegetables beside these mini-ponds for domestic needs as well as for selling. This innovative practice was started in 2009 in the Bajua union and has become the main source of water for irrigation and the practice is now being adopted by all adjacent villages.

This study also observed that poor farmers in the study area that are experiencing economic hardship as they do not have the means by which to bring water from canals or rivers such as, using laboreres or machines, and must collect water from ponds or canals by pitcher which are, in most cases, far from their paddies causing huge difficulties for the farmers. It is noted that there is no boring system for collecting irrigation water in the study areas, thus farmers must depend solely on rain water, canals and ponds for irrigation.

This study noted that during the dry season, farmers in the study areas usually use water from narrow canals which run alongside the land but it is noted that many influential people in the villages encroach on all the canals and cultivate fish in these canals which is hampering irrigation efforts for most of the farmers in the study areas. These influential people place bamboo nets over the canals and catch fish to meet their family's demands and for commercial purposes. This study found that some water related conflicts have already occurred as a result of this discrimination. In the localities of the study areas, rainwater is captured in ponds during the monsoonal months and stored for the rest of the year. Typically, the people elevate pond banks to prevent outside water intrusion and install fences to keep animals away. The surroundings are kept free of trees that readily shed leaves. If ponds become contaminated by outside water, the water is bailed out, lime is applied to the dry pond bed and the water is subsequently cleansed by applying alum. Generally, ponds are dried once in two to three year intervals in order to re-excavate and repair their banks. The people of Bajua and Laodob union have been practicing this measure to secure water for drinking and irrigation purposes. This practice significantly reduces water scarcity when salinity increases in the study areas where pond excavation is feasible. It noted that the people in the study areas use rainwater for irrigation and drinking purposes. During the monsoonal months, they construct a structure made of bamboo poles and plastic sheets to catch rainwater.

To do this, they tie together four bamboo poles, forming a rectangular shape, with one side about a foot higher than the other. A rectangular plastic sheet is then tied to the four corners of the poles. When it rains, containers are placed to collect water caught by the plastic sheet. This practice has the potential to enhance the availability of potable and irrigation water. In addition, in the study areas, the rainwater harvesting system consists of an arrangement of gutters and pipes to collect water from rooftops and direct it into a storage tank. Appropriate roofing materials include cement, corrugated iron, thatched straw, etc. Gutters are also constructed from various materials, including corrugated iron sheets, palm wood, betel nut wood, bamboo, and banana plant leaves. A 'first flush' device prevents dirt and leaves from entering the tank during initial rainfall runoff. A tightly fitted lid on the storage tank creates a moisture seal reducing evaporation.

This study revealed that, due to the high ground and surface water salinity, the people of the study areas collect rainwater during the rainy season and store it for use during the dry season. However, within a short period, insects begin to breed and nuisances are created in the water which affects the quality of the water used for irrigation and drinking. To prevent this from happening, some people keep two or three Kai fish (Climbing Perch) in the container to eat the insects and keep the water clean and free of nuisances. This practice, passed down from the elders, is practiced in the villages of Bajua and Laodob union. This study also importantly noted that, in order to keep the stored rainwater for irrigation use free from any nuisances, some people in the study areas place a paste made from two or three pieces of raw turmeric wrapped in a clean cloth into the water containers. They use this as herbal repellant in order to keep the stored rainwater free of pollution.

 

Conclusion

This study explored and documented fresh water storage practices and irrigation uses which have been adapted to suit adverse environmental and climatic conditions as well as methods employed to avoid loss of livelihood and assets and ensure availability of water and the continuation of livelihood activities that ensure agricultural productivity. In this study, researchers attempted to uncover some principles and logic underlying previously unexplored and seemingly arbitrary beliefs that have been adapted into practices for irrigation by the people of the study areas. When dealing with isolated instances collected from the field, it could appear that these practices have no coherent interrelationship that could justify a community's investment into their utilization.

Communities developed these practices out of necessity - primarily, to meet the demands of daily existence and they were developed through trial and error. These practices are not tested scientifically, but people believe in their efficacy. They continue to experiment, innovate and adapt until they find practices that produce desired results, reinforcing confidence levels. Practices are integrated into local traditions and passed down from generation to generation. Throughout the study process a wide range of data relevant to mechanisms for coping with salinity and lack of water sources were collected. The practices documented, often interwoven with cultural values, are designed or adapted to achieve specific objectives or serve precise purposes. Identical reproduction of these practices in another community or cultural setting may not be possible. However, the principles behind these practices may be replicable.

 

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