Despite world-wide efforts, that are targeted on climate change alleviation, impacts of this global phenomenon are inevitable and long-lasting. Climate change will affect each and every sector of economy, industry, and society. Despite its relative degree of versatility, the sector of drinking water supply and production will also be affected on all possible levels – from withdrawal to distribution – via a plethora of highly interconnected physical, chemical, and biological processes which are occurring within raw water sources, treatment processes, and distribution systems. Therefore, urgent requirement lies in the assessment of these processes and their impact on drinking water treatment and quality.
This research effort represents an attempt to collect and analyze information on impacts of two possible climate scenarios (warmer & drier hydroclimatic conditions and warmer & wetter hydroclimatic conditions) and five major types of extreme weather events (heavy rainfall, flood, drought, drought-breaking rainfall, and wildfire) on two major drinking water treatment processes (coagulation & flocculation and chlorination) via alterations of seven raw water quality parameters (temperature, pH value, turbidity level, organic carbon concentration, algae & cyanobacteria concentration, pathogen content, and iron & manganese concentration).
Results indicate that general raw water quality degradation, which is gradually evolving via alterations of major hydroclimatic variables of ambient air temperature or precipitation or rapidly due to extreme weather impacts, will necessitate short-term adaptations of the considered treatment processes via alteration of chemical doses and physical variables and long-term adaptations via integration of additional treatment measures of pH adjustment, organic carbon reduction, deferrization, and demanganisation since related variables can substantially change under the considered climatic conditions.