Scanty rainfall and excessive heat have created an alarming situation for farmers and fishermen in the Barind region as rivers in the region run dry and the groundwater level depletes.
Moktar Ali, a farmer from Puthimari village in Chalan Beel, said: “The groundwater became scarce as soon as the Bangla month of Chaitra arrived. Since then, it has been difficult to irrigate our lands properly because the low water pressure takes up much time and costs money.”
Fisherman Baru Hawladar from Serkol Srirampur Jelepara (fisherman colony) in Natore’s Singra said: “The Padma, for the most part, has dried up, giving rise to big chars. Besides, many more rivers, including Baral, Atrai and Gorai, the main tributaries of the Padma, are now suffering the same fate. We cannot fish if the rivers don’t hold any water.”
According to sources, the average groundwater level in Paba upazila near Rajshahi was just over 20ft during the dry season in 1975. The water level dropped below 30ft in 1995 and about 66ft in 2010.
Ghulam Sabbir Sattar, professor of environmental sciences at Rajshahi University, said: “There is a direct correlation between groundwater and river levels; one helps recharge the other. However, these normal functions of nature are being disrupted due to climate change and drought.”
If the rivers cease to exist, it will adversely affect regional livelihoods, he added.
The region's annual rainfall never exceeded 1,400mm in the seven years till 2018, which is 45% less than the national average of 2,550mm, said prominent hydrologist Prof Chowdhury Sarwar Jahan of Rajshahi University.
Last year, however, the region witnessed 1,800mm of annual rainfall.
The areas of Nachol and Gomostapur in Chapainawabganj; Tanore and Godagari in Rajshahi; and Porsha, Sapahar, and Niamatpur upazilas in Naogaon are over 47m higher than sea level.
There are areas in the same districts which are only around 10m above sea level, he noted.
"Paddy farming using only groundwater can have a toll on the availability of drinking water in these high and arid areas," he said.
Groundwater provides 75% of the water needed for rice irrigation in Bangladesh, the world's fourth-largest rice-producing country.
The Bangladesh Rice Research Institute estimates that around 3,000 litres of water are required to produce one kilogram of Boro rice.
"This estimate does not even take into account the use of water in rice mills," Prof Chowdhury said.
Wheat and maize require around 400-600 litres of water per kilogram production, he said.
As such, grain production in the region should use surface water for irrigation, he recommended, adding a focus on less water-consuming fruit and vegetable farming can help preserve groundwater in the region.
The region's groundwater level was only 30 feet below in the 1970s when farmers used surface and rainwater for irrigation and tubewells for drinking water, said BMDA's Superintending Engineer Abdur Rashid.
With the BMDA installing deep tubewells in the 1990s, farmers began cultivating three crops a year, turning the northwest into one of the country's major grain-producing regions, he said.
Following the BMDA's lead, solvent farmers and businesspeople installed their own deep tubewells.
In 2012, when the BMDA stopped installing fresh deep tubewells and moved to focusing on surface water, private tubewells continued to flourish for agricultural and industrial use.
Around 70% of the Barind region's annual groundwater extraction of 13,710 million cubic metres is done by unregulated private deep tubewells, according to a rough estimate by the BMDA recently. This amount of water would fill up around 1.8 million ponds -- each 2m deep and covering one bigha.
In February 2018, the lowest groundwater level was recorded in Nachol upazila at 107 feet below the surface, a fall of over 28 feet since 2005, when the level was at 78.8 feet.
"The fall is still on," Rashid said, adding that the levels go as low as 130 feet below the surface at the end of the irrigation season.
