By Dr Aynal Haque
RAJSHAHI: More surface water-based irrigation projects can be vital means of proportional aquifer recharge as excessive use of groundwater affecting agriculture in the drought-prone area, reports BSS.
In the wake of inadequate aquifer recharge, groundwater level is declining alarmingly in the high Barind tract posing a serious threat to its farming sector besides living and livelihood condition.
Quoting his research findings, Prof Chowdhury Sarwar Jahan said areas of 18 Union parishad (UP) and three pourasabhas in Rajshahi and Chapainawabganj districts have been identified as water-crisis hit regions.
Of those, condition of Badhair UP in Tanore Upazila and Jhilim UP in Chapainawabganj Sadar upazila is worst, added Prof Chowdhury from Department of Geology and Mining in Rajshahi University.
Protecting groundwater resources in the region and the high Barind tract in particular has become indispensable for making its agricultural system protected and sustainable.
He is conducting the research as principal investigator of ‘Integrated Water Resource Management (IWRM) project’ being implemented by DASCOH Foundation.
There are 70 deep tube-wells in Badhair area providing irrigation to more than 2,000 hectares of land for over 20 years. But, one of those remained non-functional due to lack of water source since 2015. Besides, 25 other ones have become vulnerable.
On the other hand, there are 113 deep tube-wells in Jhilim area bringing 700 hectares of land under irrigation. Of those, 12 tube-wells have become non-functional for the last couple of years.
Apart from, the Jhilim area has 32 auto-rice mills. Each of those has three to four deep tube-wells extracting huge underground water every day. Prof Chowdhury observed groundwater layer of these areas has been declined by eight to 12 feet during last two years.
Underground water level at Jhinakhoir area under Badhair UP and in Jhilim UP was in 99 and 101 feet down respectively in February, 2015, whereas the level was found in 111 and 108 feet down in corresponding month of this year.
Quoting statistics, Jahangir Alam Khan, Assistant Project Coordinator of IWRM, said the water level was available in 60 to 90 feet down during dry season in these areas around a decade ago.
Naturally, the region is around 120 feet high than the sea level. Time has come to stop extraction of underground water for irrigation purposes in the vulnerable areas.
Step should be taken to excavate and re-excavate all the existing derelict ponds and canals for boosting uses of surface water for irrigation purposes. The measures can be effective means of proper aquifer recharge.
Prof Sarwar Chowdhury attributed that the region scored significant progress in the crop production sector following expansion of irrigation facilities along with supplying water from the re-excavated canals and ponds.
He, however, said underground natural reservoirs are not replenishing due to reduced rainfall. Lower rainfall, significant drainage avulsion, cultivation pattern, withdrawal of more groundwater than its recharge and deforestation, depletion of groundwater and soil moisture in Barind area caused the groundwater drought risk.
He called for exploring the groundwater potential below 80-meter to bring more area under irrigation for its sustainable use.