Polluted Musi water used for irrigation affecting aquifers

HYDERABAD: Strange as it may sound, the continuous irrigation of agricultural and horticultural crops along the banks of the highly polluted Musi river is leading to the contamination of the city’s aquifers. Scientists from several international research institutions, including the city-based National Geophysical Research Institute (NGRI), found that the precious aquifers of Hyderabad undergoing deteriorating, year after year, as farmers increasingly depend on waste water of the Musi for cultivation.




Hundreds of farmers on the banks of the Musi cultivate crops, on thousands of acres of land all year round, thanks to perennial availability of water. Farmers bother very little if the water they use for cultivation is untreated polluted water of the river, or secondary treated water let out from sewage treatment plants (STPs) abutting the Musi in Hyderabad.

The highly polluted river water seeps into the ground and contaminates the underground aquifers that sustain the state’s water table. The problem is only compounded during the monsoon season, as percolation is higher. Chemicals present in the polluted river water also seep into the water table, changing its texture.

Many people depend on wastewater for irrigation of crops, particularly in areas where water resources are scarce or depleting. “But the questionable quality of wastewater poses health and environmental risks”, points out Jampani Mahesh, research scholar from the United Nations University’s Institute for Integrated Management of Resources and Material Fluxes (UNU-FLORES), Germany.

The study conducted revealed that water drawn from the Musi for irrigation contained a mixture of untreated and secondary treated wastewater, generated in Hyderabad. Wastewater has been in use for cultivation in peri-urban Hyderabad for a little over four decades now. “The untreated wastewater used for irrigation is expected to have adverse impacts on the local aquifers, which makes the local groundwater unsuitable for domestic, drinking, and irrigation purposes,” the scientists warned.

The international team includes researchers from Technische Universität Dresden, Germany, and International Water Management Institute (IWMI), Sri Lanka, apart from NGRI and United Nations University. The result of the study was published in the scientific journal, Science of The Total Environment.

Incidentally, in the case of river Musi, the areas irrigated by wastewater and groundwater coexist next to each other. “This means the quality of groundwater in the local aquifers deteriorates year by year, with especially salinity values on the rise,” they said.