Bengaluru: Madiwala, Agara lakes to become biodiversity parks

Bengaluru: With city lakes fast losing their aquatic biodiversity because of inflow of sewage water and toxic substances, an attempt is being made to create a biodiversity parks at Madiwala and Agra lakes in the city.

As part of the project, designed by Prof C.R. Babu of Centre for Environmental Management of Degraded Ecosystems, University of Delhi, a herbal garden, butterfly park, fruit yielding garden and an orchidarium will be set up and native aquatic species will be introduced by the Karnataka Lake Conservation and Development Authority (KLCDA).

For many years, the Madiwala Lake that spreads over 200 acres of water-spread area and about 72 acres of wetlands has been seeing hundreds of birds. A survey carried out by the civic authorities a few years ago to know the status of the lake revealed that the waterbody is a breeding zone for resident birds and feeding and resting place for many migratory birds. The survey also revealed that five species of butterflies belonging to two families, one striped palm squirrel and two species of rats/mice, two species of frogs, one species of toad, one species of lizard and five species of snakes live in the wetlands of the lake.

But now, just like any other lake in the city, Madiwala lake too is being fed with sewage waste which is posing a threat to the last remaining species at the lake. Around 12 mld of sewage waste is flowing into the lake from Hulimavu, Sarakki and Jarganahalli. The lake is also polluted with aquatic weed like water hyacinth, which has covered nearly 70% of the lake. The lake could be revived to its former glory with the new project, environmentalists feel.

Prof Babu, who was instrumental in developing the Yamuna Biodiversity Park, finds a potential in Madiwala Lake. After field visits to the lakes across the city, on the request of the Karnataka Lake Conservation and Development Authority (KLCDA) of Bengaluru, Prof Babu found Madiwala lake to be suitable for setting up of a biodiversity park. He found that Agara Lake, which spreads over 149 acres and lacks terrestrial habitat except for a small elevated land at one end of the lake, has lesser potential. He ruled out Bellandur Ammannikere Lake, which spreads over 891 acres, as it is silted and receives sewage from many interconnected lake systems. He found that the lake system was dead and it did not have any terrestrial habitat required to form a biodiversity park.

Prof Babu's project plan includes converting the marsh located at southern side of the waterbody into a mosaic of wetlands and grasslands by desilting and making low height embankments and a flat with desilted material, building a periphery of 5 to 8 meters wide bamboo green shelter belt along the boundary, the embankment and roads on the east and west will be made green ways with walkways, introduction of aquatic plants like Typha, Phragmites and Sedges. Submerged aquatic vegetation and Benthic fauna (community of organisms) and native fish fingerlings in the water body would also be introduced.

The plan also includes the creation of a Herbal Garden, Butterfly Park, Fruit Yielding Garden and an Orchidarium on the land available at the southeastern end of the water body. A 4,000 sq ft area will also be developed as a Nature Interpretation Centre. The overall plan also includes connecting Agara lake to Madiwala Lake and to develop wetland ecosystem in both lakes together.  

“Biodiversity parks serve as nature reserve for the conservation of lost natural heritage of the city, apart from serving as a hub for education, cultural and conservation activities, a living lab for understanding the ecosystem processes and functions, enhancing the quality of urban environment, promoting ecotourism, creating a buffer local weather and serving as sink for CO2 and urban pollutants. It also preserves the rare, endemic threatened plants and animal species of the area and even ecosystem due to developmental activities. It is will also serve as a habitat for gene pools of land races of economically important crops," reads the report by the Karnataka Jnana Aayoga.

Officials at the department of Forest and Ecology said that Madiwala Lake will be developed at Rs 24 crore, while Agra Lake at Rs 16 crore. The project plan has been approved, and the work is expected to commence soon.