Improvement of Designs for Enhanced Infiltration Rates in MAR (Managed Aquifer Recharge) Technique at the Coastal Aquifers of South-Western Bangladesh

English Abstract:

Increasing salinity of natural drinking water sources has been reported as one of the many problems that affect low-income countries, but one which has not been fully explored.

Drinking water from natural sources in coastal Bangladesh has become contaminated by varying degrees of salinity due to saltwater intrusion from rising sea levels, cyclone and storm surges, upstream withdrawal of freshwater and increased shrimp and crab farming along the coastal areas. This crisis is also exacerbated owing to climate change. The problem of salinity can have serious implications with regard to rising rates of hypertension and other public health problems.

There are very few options of safe drinking water for more than 2 million people living in these regions. During dry period people of those areas rely largely on surface or pond water, PSFs and RWHs which can be vulnerable to pathogens and thus suffer largely from lack of safe potable water and health problem.

A potential solution was very much needed to overcome the fresh water scarcity problem of the area. Managed Aquifer Recharge (MAR) is an alternative, cost effective and durable option to store fresh water (roof top rain water and filtered pond water) into shallow brackish aquifer during the monsoon and subsequent recovery of fresh water from storage and its supply to the community people during the dry period.

About 70 percent rainfall occur during the monsoon period in the coastal belt of Bangladesh (Khulna-Satkhira) is potential for MAR. MAR techniques operate to store the rain water into underground aquifer, reduce the salinity and then get recovery of fresh water from groundwater storage which is provided to local people as a safe source of drinking water throughout the year particularly during dry season.

The successful implementation of MAR technique has brought “the solution” of drinking water problems in some extent in the SW coastal areas of Bangladesh. The improvement of design in MAR is required for enhanced infiltration rates. So the expected result would be the maximum infiltration as it ensures more freshwater storage, better quality improvement of groundwater and more availability of safe drinking water with minimum management cost for the community people.