Shallow Tubewell Irrigation System in Bangladesh: Perspective Structure, Management and Performance

Abstract

Shallow Tube Well (STW) irrigation system in Bangladesh reduces the uncertainty of variable rainfall patterns for rice production. The application of groundwater irrigation by STW technology increased with the introduction of High Yielding Variety (HYV) seeds to meet the food requirements of a growing population. STW irrigation system has utmost importance for food production and food security and ultimately raises the income of farming households and enables them to attain a better quality of life. That's why, the present study was undertaken to introduce structure, management and performance of STW irrigation technology. The objectives of this study were to acquire an integrated understanding of the structure of STW irrigation, to examine the management system of STW irrigation business, to understand the profitability both for STW owner and irrigators (water buyer) and to draw recommendations for sustainability and cost-effective STW irrigation business as well as Boro rice production for the coming future. Field survey and different field measurements were carried out in Dighalkandi Union (covering five mouza) under Ghatail Thana of Tangail District during Boro (winter, irrigated) season in 2016 and 2017. Both STW owners and irrigators were chosen as samples for this study and they were surveyed through two sets of questionnaire. Complete survey technique was used for the STW owners. A total of 50 STW owners were found in the study area operating their STW irrigation business. Out of 50 STW owners, Diesel Operated STW (DOS) owners were 2 and Electric Operated STW (EOS) owners were 48. To assess the performance of business in both cases, two-stage stratified random sampling technique was used to collect data from the irrigators. Firstly, 12 STW owners were selected randomly from all and then five water buyers were also randomly chosen from each of the selected 12 STWs. So a total of 110 samples (50 STW owners, 10 DOS irrigators and 50 EOS irrigators) were used for this study. Selected 12 STW schemes performances were evaluated using some standard hydraulic, agricultural and socio-economic indicators. The study revealed that the study area was suitable for Boro rice cultivation using groundwater by STW irrigation due to its geographical and physical features such as water bodies, rainfall, land type category, soil type, topography, lithology, aquifer characteristics and groundwater availability and suitability. At present electric operated STW (EOS) was mainly used in the study area for groundwater abstraction. In 2017, diesel operated STW (DOS) were 4% and EOS were 96% in the study area. Last 10 years DOS has been decreased and EOS has been increased 40% respectively in the study area. The study findings showed that belonging wide ranges power of engines or motors were found in use in the study area and most of the engines were Chinese and Japanese. Pump discharge, water productivity and land productivity of both engines (diesel and electric motor) considering same as BHP were little bit similar. The performances of selected 12 STW schemes were performing better than in the past. There was almost trapezoidal characteristic of channel and all field channels were Kutccha in the study area. There was scope for improvement of channel dimension to save land as well as water losses by reducing width of distribution channel. The research findings showed that mis-match among different parameters of STWs were observed in the study area and this overall mis-match mainly occurred due to lack of technical knowledge and information of the STW owner, mechanics, farmer, equipment traders and installers. The data showed that the majority of the STW owners (60 percent) run their management activities through partnership arrangement and 40 percent STW owners run by single ownership. The management of STW operation by partnership was found to be more efficient compared to management by single owners. Also data revealed that a majority (57 percent) of the owners was found to possess higher social statuses who actively engage in local social institutions. The STW irrigation business was reasonable profitable at the current (2017) price of input cost and output return, but this business will become unprofitable for DOS in uncertain situation considering 10 percent increasing of O & M cost or 10 percent decreasing of benefit or 10 percent increasing of diesel price. The EOS was more profitable than DOS due to increasing of diesel price and lower electric charges compared to fuel and lubricant cost and coverage of higher command area by EOS. Boro rice production was higher profitable when farmers grown it in his own land with family labor. In this case, returns to family labour were US$ 6.41 (Tk. 500) and US$ 7.17 (Tk. 560) per man-day considering the year 2016 and 2017 respectively, which was quite higher the then normal wage. When all inputs including land and labor are hired, Boro rice production was not profitable. In cases of all inputs hired except labor, Boro rice production was reasonably profitable and all inputs hired except land, Boro rice production was marginal profitable to the farmers. Boro rice production was a competitive business in rural market and was strongly able to compete with other business. Boro rice production has great importance for the socio-economic development of Bangladesh due to its suitability and sustainability. This study recommended that STW irrigation business and Boro rice production could be made profitable with proper management of input cost and output price, effective use of the system and improving the management practices of soil, water and crop.