The Cox’s Bazaar District in Bangladesh is hosting a massive rapid, influx of over 700,000 Rohingya Refugees from Myanmar, placing huge strain on local resources including water resources. The largest camp, known as the Mega Camp, is spread across a 13km2 block of land between Kutupalong and Balukhali. Water supply for this camp is sourced from the underlying Tipam Sandstone Aquifer. The aquifer comprises over 400m of loosely compacted and structurally deformed Miocene aged sandstone. To date, the Tipam Sandstone Formation has received little study but is being pumped at an unprecedented rate. A sustainable water supply for all residents of the Mega Camp and surrounding areas depends on a sound conceptual understanding and carefully managed development of the underlying groundwater resource. With this aim in mind, Groundwater Relief in collaboration with Médecins Sans Frontières Holland, have been engaged in collecting groundwater data since January 2018 across a 7km2 area. New boreholes drilled have been logged and pumping tests carried out. A monitoring programme was established including the installation of 10 water level data loggers across a network of monitoring and abstraction boreholes; the set up of three rain gauges; and a monthly water quality monitoring programme across 12 boreholes measuring basic field parameters. Hydrographs comparing rainfall with groundwater levels relative to sea level showed groundwater levels quickly increased on the onset of the rainy season with a 1.5m increase over one month in July 2018. Groundwater levels increased almost simultaneously to peak rainfall events, suggesting rapid infiltration and recharge. Elevated ferrous iron concentrations were encountered in the top 120m of the aquifer with lower concentrations found at greater depths. Electrical Conductivity values in the groundwater are significantly below the Bangladesh Standard of 1500 μS/cm at present.
Over the course of 2019 Groundwater Relief is working with Dhaka University and the International Organisation for Migration to expand the monitoring programme across the entire Tipam Sandstone Outcrop in Cox’s Bazaar. As part of this programme a groundwater model and management tools will be developed to support the Bangladesh Authorities with the planning of new water supplies for the camp and the host population.