Despite directives from the National Green Tribunal, the lake continues to receive untreated wastewater through rajakaluves, leading to foul odour and deteriorating water quality.

Members of the Yelahanka-Puttenahalli Lake and Bird Conservation Trust have flagged serious violations, alleging that the Bangalore Water Supply and Sewerage Board diverted untreated sewage into the lake without proper permissions by altering the walkway.

The Trust has stated that it will present the current condition of the lake before the tribunal in an upcoming hearing.

Earlier, the Bruhat Bengaluru Mahanagara Palike (BBMP) had assured the construction of a diversion pipeline to prevent sewage inflow. However, the project remains incomplete, raising concerns about accountability.

Officials from the Forest Department, the custodian of the lake, have expressed frustration over the lack of action despite repeated notices to concerned agencies.

Declared a conservation reserve under the Wildlife Protection Act 1972 in 2015, the lake once supported over 400 species of birds. That number has now dropped to fewer than 200.

Experts note that birds now only roost on the islands and avoid feeding in the lake due to poor water quality and declining aquatic life.

The lake had earlier been rejuvenated in 2014 through collaborative efforts involving local communities, the Forest Department, and institutions such as the Indian Institute of Science and GKVK.

However, ongoing pollution now threatens to undo years of conservation work, raising urgent questions about sustainable urban management and environmental protection.