CHENNAI: Velachery lake and Okkiyam Maduvu canal, which were adorned with hundreds of spot-billed pelicans not more than a few weeks ago, have lost their charm due to a serious infestation of water hyacinth once again.
Despite the Public Works Department removing the invasive plant just a month ago, the weed has carpeted the water surface once again. Earlier this year, the Water Resource Department had allocated `25 crore to convert Velachery lake into a tourist spot.
However, a comprehensive plan is yet to be laid out. With the monsoon fast approaching, residents fear outbreak of mosquito-borne diseases. Water hyacinth is one of the fastest growing plants that has runners or stolons, which eventually form daughter plants, as the primary means of reproduction. It also produces large quantities of seeds that are viable for up to 30 years. Because of water hyacinth’s ability to quickly reproduce, populations often double in size in just two weeks. “One can only control the growth of these plants, not eradicate it,” said K V Sudhakar from Madras Naturalists Society.
The invasive plant is a strong indicator for pollution. When not controlled, the plant grows rapidly covering the entire surface of the water, preventing sunlight from entering the depth of water. This starves the natural biodiversity of the water body making it further polluted. The migration season is just around the corner, but the polluted water body may not attract many birds this time.
“Effluents and sewage are released into several parts of the lake. Lack of significant initiatives by Metrowater officials to prevent this has only made the water body worse,” charged Kumar Raja, president of Velachery Residents Welfare Association. The Velachery lake, that once spread across nearly 250 acres from Velachery to Adambakkam, has shrunk to a fourth of its size due to encroachments.