HYDERABAD: Improved groundwater levels across Telangana have not translated into safer drinking water. Despite groundwater rising in 98% of monitored wells following excess rainfall and strong recharge, the latest assessment by the groundwater department has found persistent fluoride and nitrate contamination across several districts.
The report recorded fluoride levels as high as 13.9 mg/l in Mancherial district and nitrate concentrations of 697 mg/l in Nizamabad and 683 mg/l in Kamareddy. According to World Health Organisation (WHO) guidelines, the permissible limits are 1.5 mg/l for fluoride and 50 mg/l for nitrate in drinking water.
A report by the Ministry of Jal Shakti further revealed that 28 districts in Telangana have excess fluoride, while 32 of the state’s 33 districts exceed safe nitrate limits, making Telangana the third-worst state in the country for nitrate pollution.
The assessment, based on more than 2,200 groundwater samples collected during pre- and post-monsoon seasons, found contamination from fluoride, nitrate and salinity in several parts of the state.
Fluoride contamination remains one of Telangana’s most significant groundwater quality concerns. Affected districts include Nalgonda, Rangareddy, Siddipet, Yadadri Bhuvanagiri, Hanamkonda, Jangaon, Bhadradri Kothagudem, and parts of Nagarkurnool and Mahbubnagar. Fluoride concentrations ranged from 0.01 mg/l in Komaram Bheem Asifabad district to 13.9 mg/l in Mancherial during the pre-monsoon season.
Nitrate contamination is even more widespread, with elevated levels detected in isolated pockets of nearly every district. Experts attribute this largely to human activities such as excessive use of chemical fertilisers, agricultural runoff, sewage seepage and wastewater infiltration.
The report notes that fluoride contamination is primarily linked to Telangana’s geology. Nearly 81% of the state is underlain by hard-rock formations, including granites, gneisses, schists, quartzites and Deccan basalts. Groundwater stored in these formations remains in prolonged contact with fluoride-bearing minerals, causing fluoride to dissolve into aquifers over time.
Environmental experts warned that improved groundwater availability alone cannot guarantee safe drinking water. “There is a need for sustained groundwater quality monitoring, better fertiliser management, protection of recharge zones and targeted interventions in fluoride- and nitrate-affected areas,” said Kalpana Ramesh, founder of the Rainwater Project.
Environmentalist Donthi Narasimha Reddy stressed the importance of preventing untreated sewage and wastewater from entering aquifers and promoting sustainable agricultural practices to reduce contamination.
The assessment also highlighted salinity-related concerns. Total dissolved solids (TDS), an indicator of salinity, reached 4,851 mg/l in Mulugu district during the post-monsoon season, while some locations in Sangareddy recorded values exceeding 8,000 mg/l. Although TDS is not considered a major health hazard, high concentrations can make water unpalatable and cause scaling problems.
The findings come at a time when Telangana is witnessing one of its strongest groundwater recoveries in recent years. During the 2021-22 water year, the state received 1,181 mm of rainfall against a normal average of 906 mm. Monitoring data showed groundwater levels in May 2022 were 3.35 metres higher than the decadal average, with Nizamabad recording the highest average rise of 7.66 metres.
The report underscores a critical challenge for Telangana: while groundwater availability has improved significantly, persistent contamination continues to threaten drinking water security across the state.
EL NINO: FARMERS URGED TO SHIFT FROM PADDY
With weather experts warning of drought-like conditions due to El Niño, officials in the erstwhile Medak district and Karimnagar are urging farmers to reduce paddy cultivation and opt for alternative crops during the Kharif season. Authorities are promoting oil palm, pulses, millets, oilseeds, cotton, maize and vegetables through awareness drives and field visits. Collectors in Siddipet and Karimnagar directed officials to encourage climate-resilient farming, ensure quality seed availability and share weather advisories. Agriculture officials also cited poor groundwater recharge and low water levels in the Singur project as concerns for the upcoming season.