4. Impacts of Climate Change on Water and Sanitation System in
Bangladesh
S. M. Helal Uddin, Senior Lecturer, Department of Civil Engineering, World
University of Bangladesh
Climate change will have significant impacts on water resources, as there
is very close connection between the climate and hydrological cycle. Rising in
temperatures will lead to increase evaporation and precipitations, frequent
and extreme floods and droughts in different regions at different times.
Variable precipitations pattern and snow melt will influence water
availability, water supply, sanitation, water contamination and drainage
congestion. Climate changes are likely to lengthen the transmission season
of vector-borne diseases and alter their geographic range; floods, droughts,
cyclonic storms will disrupt water supply, sanitation. Both the water quality
and quantity may be affected due to the impacts of climate change such as
sluggish flow of groundwater due to reduce hydraulic gradient, intrusion of
saline water in the coastal groundwater, lowering of water table due to lower
recharge. Sluggish groundwater flow due to climate change and sea level rise
is likely to increase arsenic contamination. In Bangladesh, 30 million of
people drink arsenic contaminated water beyond the acceptable level
(0.05mg/L) and more than 50 million beyond the WHO standard (0.01 mg/L).
More than 38,000 Arsenocosis patients have been identified by national
screening. 85% and 60% people have access to safe drinking water in rural
and urban areas, respectively. On the other hand, floods in the monsoon will
increase dilution factor and aeration of water causing a decrease chemical
and organic pollution but submergence of sanitation and sewerage facilities
during high floods and cyclones may cause increased microbial
contamination of water. The two diseases- diarrhoea and dysentery are the
main cause of death during floods due to drinking of polluted water.
Microbial activities become double for each 10°C increase of temperature.
The increase of 1.4 to 5.8 °C temperature will result in 14% to 58% increase in
microbial activities and dissolved oxygen content of water reduction at
higher temperature. This study suggested to consider more technological
options for both urban and rural areas considering both eco-sanitation and
raising of mass awareness about climate change for improved water and
sanitation systems.
06 4th National Knowledge Convention