The Unique Approaches to Water Management for Transforming Bangladesh’s Drought-Prone Northwest Region into a Lush and Granary Landscape

Abstract

Bangladesh’s Barind Tract, lying in the country’s northwestern part, is a drought-prone water scarce area that has suffered substantial difficulties in water management for agriculture, drinking, residential, and other uses. The situation has been changed by the efforts of the Barind Multipurpose Development Authority (BMDA). So, the focus of this research is on the numerous initiatives of the BMDA to transform the arid-like Barind area into a green and granary landscape through efficient water management. To achieve this goal, various data sets about water resources development and management, as well as other necessary information were collected from the BMDA and other sources and analyzed. Irrigation was initiated using groundwater (GW) through the installation of deep tube wells (DTWs). DTWs located near the localities are also used to provide drinking water to rural people. Then, by re-excavating derelict ponds, kharis (canals), and other water bodies and constructing cross-dams (check dams) and rubber dams in the re-excavated kharies and rivers, surface water (SW) augmentation is started, mostly for supplementary irrigation. Conserved water develops the environment and enhances groundwater recharge (GWR) alongside irrigation. Constructed dug wells in the severely water-stressed areas having no sources of SW and GW supply irrigation for low-water-consuming crops. Pre-paid metering in the irrigation management system has minimized the overuse of water, while the underground pipe water distribution system has reduced water transportation and evaporation losses. The application of managed aquifer recharge (MAR) model helps enhance GWR. Finally, BMDA’s efforts have transformed the Barind Tract, as well as Bangladesh’s northwest region, into a lush and granary terrain.

1. Introduction

The Barind Tract includes parts of the greater Rajshahi, Pabna, and Bogura districts of the Rajshahi Division, as well as parts of the greater Rangpur and Dinajpur districts of the Rangpur division in Bangladesh, as well as parts of the Uttar Dinajpur, Dakhin Dinajpur, and most of Maldah District in West Bengal, India. The Barind Tract in Bangladesh's northwest is the country's largest Pleistocene terrace, made up of Pleistocene alluvial deposits, often known as older alluvium, covered by reddish-brown, sticky Pleistocene silt; Madhupur Clay, with an elevation above sea level ranging from 14 to 45 m [1, 2, 3, 4, 5, 6]. The area is geomorphologically separated into three geological units: (a) Barind clay residuum, which overlies and formed on Pleistocene alluvium; (b) Holocene ganges flood-plain alluvium; and (c) Ganges active channel deposits and main distributaries (modern alluvium).The floodplain and the Barind Tract are both physiographically included in the area, which is tectonically part of the Bengal basin's stable shelf region. Level Barind, high Barind, and north eastern Barind are the three primary portions of the Tract [6, 7]. The area's central section is relatively high and irregular. About 80% of the land in high Barind is terraced or undulated. The Tract is located between the latitudes of 24°20'N and 25°35'N, and the longitudes of 88°20'E and 89°30'E. In comparison to other areas of Bangladesh, the Barind Tract's hard red soil and typical dry environment with comparatively high temperatures and low rainfall are crucially significant [8]. The temperature ranges from 8 to 44 degrees Celsius throughout the area [2]. Although the national average for annual rainfall is 2500 mm, the Tract receives lower rainfall ranging from 1250 to 2000 mm, with about 80% of it falling between June and October [9, 10]. The Barind Tract is the most drought-prone and water-scarce region of Bangladesh, with very limited sources of surface water [11, 12]. The area is experiencing groundwater drought, a type of hydrological drought, as well as agricultural drought caused by weather events. In the years 1972, 1975, 1979, 1982, 1986, 1989, 1992, 1994, 2003, 2005, 2009, and 2010, it endured moderate to severe agricultural droughts with hydrological droughts [13]. Because the land is almost flood-free, rainwater is the only means of recharging groundwater [9, 14]. However, rainwater percolation to the aquifer is restricted by more than 15 m thick top clay (Barind clay) layers [15, 16, 17] and limited infiltration capacity (2–3 mm/day) [18] reduces natural groundwater recharging [19]. Before 1986, the typical landscape of this region was sun-burned hot-tempered high and low ground with cactus, babla (acacia), herb, and palm trees scattered about [7] and surface water supplies were scarce, and most ponds, canals, rivers, and other natural water bodies dried up during the dry season, leaving crop production entirely dependent on rainfall. Here, only rain-fed T. Amon (Transplanted Amon) (local name of paddy) crops were grown whose cultivation was impeded by a lack of timely rainfall, and field crops were frequently damaged. After T. Amon was harvested, the land remained uncultivated for the remainder of the year due to a lack of water and was used as cattle pasture and people did not have any work with their hands at the time. So, they had to migrate to other parts of the country in search of work. There was an acute shortage of drinking water. For drinking and domestic usage, women used to collect water from open water bodies where cattle were also washed. As a result, many people had to suffer from various water-borne diseases, such as cholera, diarrhea, and dysentery [8, 10, 17]. When the ponds dried up during the dry season, they experienced a major setback in obtaining water to drink. People in the area are familiar with the motto “Barind is a land where life is written in water” [3]. As a result, life was extremely hard, and the area was woefully underdeveloped. In response to the people's and area's vulnerable situation, the Government of Bangladesh approved the “Barind Integrated Area Development Project (BIADP-I)” under the Bangladesh Agriculture Development Corporation (BADC) in 1986 and, thus the development of the area was started. The project area included three districts: Rajshahi, Nagaon, and C. Nawabganj [20]. The major goal of the project was to boost crop production through the creation of irrigation facilities and to contribute to food security. However, due to administrative difficulties and a delay in the release of funds by BADC to the project authority, the project's progress was hampered. In 1992, Barind Multipurpose Development Authority (BMDA) was established under the Ministry of Agriculture to address this issue and ensure the project's seamless operation. The government approved BIADP-II, and the BMDA successfully implemented it on time. In 2003, the Gov. handed over 1217 unused deep tube wells (DTW) from then north Bengal DTW project of the Bangladesh Water Development Board (BWDB) under Thakurgaon, Dinajpur, and Panchogar districts, recognizing the BMDA's achievement. Within a year, BMDA had successfully put all of the DTWs into operation [21]. Finally, in 2018, the Bangladesh government enacted an act that expanded the BMDA's jurisdiction to include all 16 districts of the Rajshahi and Rangpur Division. Figure 1 depicts the sequential expansion of BMDA's jurisdiction.

Figure 1.

The map of the sequential expansion of BMDA’s jurisdiction into 16 districts of Rajshahi and Rangur division of Bangladesh.

The main goal of BMDA is to turn its land into a granary by creating irrigation facilities. So, the aim of this study is to discuss the water resources development and management activities of BMDA and evaluate them.

2. Materials and methods

Information on deep tube wells (DTWs) for groundwater extraction and irrigation, re-excavated canals, ponds, cross dams (check dams), rubber dams for surface water augmentation, dug well and recharge well for rainwater harvesting and groundwater recharge, buried pipelines, drinking water supply installations, prepaid meter for irrigation water management, and other pertinent information were collected from the Barind Multipurpose Development Authority (BMDA), and other sources. Different studies were also reviewed. Finally, all of the data and information were checked for accuracy and consistency before being processed in the appropriate format.

3. Results and discussion

3.1 Groundwater irrigation

Because surface water sources are limited in the Barind Tract, irrigation was started with groundwater through the installation of DTWs. There was no way to collect water without DTWs since the aquifer was so deep in the ground (more than 15 m below the surface). Groundwater is now the primary source of irrigation, drinking, and other uses. Deep tube wells were initially run by diesel engines, which caused plenty of problems for farmers, including crop damage. DTW was then electrified for smooth operation, with a submersible motor pump replacing the diesel engine. Some of the irrigation water recharges groundwater through percolation and some go back into the atmosphere, which helps to improve the environment. Figure 2 shows a DTW in a crop field.

Figure 2.

A deep tube well in a crop field with buried pipelines (source: [22]).

3.2 Derelict kharies and pond re-excavation and rainwater irrigation

Derelict kharies (canals) ponds and beels (natural water body larger than pond) were re-excavated to augment surface as well as rainwater water by increasing their water holding capacity. For conserving rainwater, cross dams/check dams are constructed at different sections of the re-excavated canal maintaining a certain gradient, depth, and width. Conserved water is mainly used for supplementary irrigation. It also helps to develop an environment and enhance groundwater recharge (GWR). Figure 3 shows the rainwater conservation system by the re-excavated canal, pond, and beel. Electricity-driven or solar-powered low lift pumps (LLPs) is used to withdraw the conserved water for irrigation (Figure 4).

Figure 3.

Surface water augmentation by (a) re-excavated canal, (b) cross dam (check dam) in the re-excavated canal, (c) re-excavated pond and (d) re-excavated natural beel utensils (source: [22]).

Figure 4.

(a) Irrigation by electricity-driven and (b) solar-powered LLP utensils (source: [22]).

3.3 Irrigation using river water

A floating pontoon with the necessary centrifugal pumps is placed on the river. Pumps are used to draw water from the river and discharge it to the re-excavated canal through an underground pipeline. Water is then withdrawn from the canal by LLP to irrigate the crop fields. As indicated in Figure 5, it is a double-lifting irrigation system.

Figure 5.

Double lifting irrigation system: (a) Pontoon with centrifugal pumps floating on the river and (b) discharging river water to the canal (source: [29]).

This system of pontoons on the rivers Padma, Mohanonda, and Atrai lessens groundwater exploitation by 7.08% for the respected Upazilas' area [29].

The irrigation with river water is also operated by constructing a rubber dam across the river to conserve water upstream (Figure 6). The LLPs are used to irrigate the crop fields. A rubber dam built across the river Barnai in Puthia Upazila reduces groundwater withdrawals by 10.11% [29].

Figure 6.

A rubber dam was constructed across the river (source: [12]).

3.4 Buried pipeline water distribution system

Every irrigation scheme has buried pipelines for conveying water from the pumping station to the agricultural field. It is suitable for the undulated terraced Barind land. Water can be conveyed from a lower elevation to a higher elevation with this system and conveyance and evaporation losses in the pipeline part are minimized. Because the pipeline runs beneath the earth's surface, valuable land is saved. The system is shown in Figure 7.

Figure 7.

Buried pipeline system: (a) pipe laying stage, (b) header tank for raising pressure head, and (c) outlet with air vent (source: [22]).

3.5 Dug Well (DW) irrigation for severely water-stressed area

A dug well is typically built in a severely water-stressed environment with no sources of surface water or aquifer that produces groundwater. By a dug well, low water consuming crops, such as tomato, cauliflower, chilies, eggplant, and other vegetables, can be cultivated. During rainfall, rainwater (RW) is collected by the solar panel cum rainwater harvesting device and stored in the dug well. A solar-powered pump lifts the stored water to an overhead tank; it is then fed to the crop area for irrigation. The details of DW are shown in Figure 8.

Figure 8.

A dug well in a vegetable field (source: [12]).

3.6 Prepaid metering in irrigation management

To avoid the overuse of valuable water, BMDA has introduced a prepaid metering system in irrigation management. Each farmer has a prepaid card (user card) that can be recharged by paying a certain amount of money to the BMDA local office or recruited dealer. When a farmer needs irrigation water for his crop field, he inserts his card into the irrigation equipment's prepaid meter, such as DTW or LLP. If the card has a balance, the irrigation pump automatically starts and distributes irrigation water. The DTW automatically turns off when the balance on the inserted card is zero or the card is removed from the meter. Farmers only use irrigation water for the actual needs of crop fields because it is a prepaid system. As a result, by lowering irrigation expenses, the overuse of irrigation water is reduced. The irrigation actions of this system can be monitored centrally through the internet using a digital method. Now, for all farmers of an irrigation scheme, it is possible to cultivate crops with less water. Figure 9 depicts the system.

Figure 9.

Prepaid metering system: (a) a woman inserts her prepaid card into the irrigation equipment's prepaid meter, and (b) the system is monitored over the internet network from the BMDA's headquarters (source: [22]).

3.7 Application of MAR model to enhance groundwater recharge

In 2016, at the BMDA Mohanpur zonal office site, a recharge well (RW) with a water filter unit (FU) was built as a modified MAR model taking into account the lithology, as well as the aquifer condition and maximum daily rainfall (Figure 10). The uPVC pipeline collects rooftop rainwater from the office building and a training shed, filters it via the FU's sand-gravel filtration media, and then recharges the groundwater through RW. To monitor water level fluctuations, an observation well (OW) with an auto water level recorder (AWLR) system has been installed. The rainfall data is recorded at a rain gauge station. The water level may now be automatically monitored from the BMDA headquarters in Rajshahi via the internet network every day of the year, which is the pioneer attempt in Bangladesh [17].

Figure 10.

BMDA Mohanpur office campus MAR model: (a) schematic view of whole MAR model, (b) longitudinal sectional image of FU and RW, (c) photo of FU with RW, and (d) GWL hydrograph illustrating recharge performance with rain water infiltration (source: [12]).

3.8 Drinking water supply

There was an acute shortage of drinking water (DW) in this area. So, finding no way, people had to collect pond water for drinking, domestic and other usages faced multifarious water-borne diseases like cholera, diarrhea, dysentery, etc. About 15% of irrigation wells of BMDA are located near the villages. A 25,000 liter capacity overhead water tank with a 2400 m pipeline network is constructed to supply drinking water to the rural people from this irrigation well alongside irrigation. Figure 11 shows the drinking water supply system in detail.

Figure 11.

(a) An overhead water tank close to an irrigation DTW, (b) women are collecting water for drinking purposes, and (c) using the system's water, a woman is washing utensils (source: [22]).

Through the analysis of collected data and different studies following observations can be mentioned:

• The buried uPVC pipeline system has a mean conveyance efficiency of between 94.46 and 95.37%, with a rate of water loss of between 5.45 and 6.11%, and about 80% of farmers commend it [23]. For the 15525 DTW schemes, a total of 2000 hectares of land have been saved [24].

• About 0.52 million hectares of land have been brought under-regulated irrigation facilities with the installation of 15525 DTWs and 13,512 km buried pipelines, benefiting 0.96 million farmers [25].

• With 3357 re-excavated ponds, 2063 km of re-excavated canal, 747 cross dams built at various portions of the re-excavated canal, 11 floating pontoons with required pumps set up on the river Padma, Mohanonda, and Atrai, and a rubber dam, 97,000 hectares of land have been possible to irrigate. To irrigate crop fields, 601 electricity-driven LLP and 168 solar-powered LLP are used. A total of 171,000 farmers are being benefited from the current system [25].

• The installation of 572 dug wells has enabled the irrigation of low-water-use crops on 1620 hectares of land, benefiting around 11,000 farmers [25].

• Due to the construction of 1579 drinking water supply infrastructure, about 1,250,000 rural people now have access to potable water [25].

• Every year, around 300,000 liters of rainwater replenish groundwater from the MAR infrastructure established at the BMDA Mohanpur office [17].

• The installation of a prepaid meter system in irrigation management reduced the overuse of valuable irrigation water and resulted in a 22% increase in the command area [26]. The private irrigation system (PIS) has an average irrigation cost, that is, 112% higher than the prepaid meter irrigation system (PMIS), and the PIS uses 39% of the extra water [27]. This research shows that the prepaid irrigation scheme is a cost-effective and ecologically friendly way to increase rice production in the study area [27].

• Since 1986, cropping intensity has increased from 113 to 230% [3, 28, 29].

• As a result of BMDA's efforts to develop and manage water resources, single-cropped dry land has been turned into triple-cropped land, making it green and granary.

4. Conclusions

Due to the augmentation of groundwater by 15525 DTWs along with 13,512 km buried pipeline, 0.52 million hectares of land are now under groundwater irrigation benefiting 0.96 million farmers. Due to the augmentation of surface water by 3357 re-excavated ponds, 2063 km of the re-excavated canal, 747 cross dams, 11 pontoons, and a rubber dam, 97,000 hectares of land have been brought under surface water irrigation, benefiting 171,000 farmers. When compared to surface channel, buried pipeline increased conveyance efficiency from 94.46 to 95.37%, saving 2000 hectares of land at the 15525 DTW schemes. The introduction of prepaid meters has reduced irrigation water usage, resulting in a 22% increase in the command area. About 1,250,000 rural people receive potable water from 1579 drinking water installations.

Conserved water from re-excavated water bodies and irrigation water from crop fields assist replenish groundwater and enhance the environment in tandem with irrigation, which requires extensive research to determine the exact amount of recharge. A single MAR can replenish groundwater with over 300,000 l of rainwater. As a consequence of BMDA's innovative endeavors in water resource augmentation and management for diverse reasons, the land has been turned into a lush and granary environment. To improve groundwater recharge, other office buildings, training sheds, educational institution buildings, commercial buildings, and residential houses should be placed under the managed aquifer recharge program. More canals ponds and other derelict water bodies should be re-excavated to conserve additional surface water and utilize more river water, and they must be maintained on a regular basis to ensure their long-term viability. For sustainable usage, future planning and management of water resources in the area, a comprehensive assessment of groundwater, and surface water resources, including zoning, is required.