Seasonal variation in the microbial quality of shallow groundwater in the Kathmandu Valley, Nepal

Groundwater microbial quality in the Kathmandu Valley, Nepal, deteriorates significantly during the wet season compared to the dry season. This seasonal variation is attributed to increased infiltration of fecal material and rising groundwater levels, which likely introduce contaminants into shallow aquifers. The study, conducted from 2009 to 2012, analyzed Escherichia coli and total coliform concentrations in dug wells monthly for a year, revealing a moderate to strong correlation between microbial contamination and groundwater levels. These findings highlight the need for targeted pollution control strategies to mitigate seasonal fluctuations in water quality, particularly during monsoon periods.

Shrestha, S., Nakamura, T., Malla, R., & Nishida, K. (2013). Seasonal variation in the microbial quality of shallow groundwater in the Kathmandu Valley, Nepal. Water Supply, 14(3), 390–397. https://doi.org/10.2166/ws.2013.213