Rapid urbanisation and lack of efficient waste disposal systems seem to have left a significant number of waterbodies in Ernakulam gasping for life.
The bane of large-scale reclamation of filtration ponds and tidal marshes, encroachments and solid and liquid waste has taken a toll on rivers, lakes, and canals in the district, according to studies conducted by experts.
“The deteriorating condition of the Periyar, which is the sole drinking water source for lakhs of people, stands testimony to the fact that urbanisation and unchecked pollution have sounded the death knell for waterbodies,” said Dr. S. Bijoy Nandan, professor and head of the department of marine biology, microbiology, and biochemistry at the School of Marine Sciences at the Cochin University of Science and Technology (Cusat).
“Studies have shown that the Periyar, near the upstream of the Pathalam bund as well as several pockets in the downstream regions, has become barren, dead with high organic load, nutrient enriched, polluted micro ecological habitat, leaving aquatic life paralysed,” he added.
Dr. Bijoy Nandan pointed out that household / domestic waste from Aluva and Kalamassery regions is a major pollutant in the upstream stretches of the Periyar. “Measures have to be taken to establish an integrated waste treatment system / management system in the upstream region of the Periyar for treating household waste from Aluva and Kalamassery,” he said.
V.N. Sivasankara Pillai, former director of the School of Environmental Studies at Cusat, said several waterbodies that were once freshwater sources had either vanished or shrunk owing to encroachments and discharge of untreated wastage into them.
“The Edappally thodu, which was once known as ‘thukalan kuthiya thodu’, is a telling example of how encroachment can render a waterbody lifeless. The canal was the safest and shortest route for movement of goods along the Kodungalloor-Varappuzha-Muttar puzha-Thripunithura channel since the erstwhile Travancore-Cochin period. It was also a seasonal freshwater source,” he said.
Maintaining that the original expanse of the canal had reduced considerably, Dr. Pillai said encroachments in the form of construction of apartments, business establishments, and houses near the canal had hit the natural ecosystem of the waterbody.
“The situation is no different if we take the case of the Kadambrayar creek or the Perandoor canal. While leachate from the dumpyard at Brahmapuram had polluted the Kadambrayar, the rollout of the tourism project connected with the waterbody had resulted in its further deterioration. Even today, untreated sewage from houses located close to the Perandoor canal is discharged into the waterbody,” he added.
The other water channels hit by urbanisation and pollution include Mullassery canal, Thevara canal, Perandoor canal, Karanakkodam thodu, Koithara thodu, Poornipuzha, Changadampok thodu, Kharee thodu, and Puncha thodu, according to studies conducted by experts from Cusat.
Ajit Haridas, Chairman of the Kerala State Pollution Control Board, referred to the lack of scientific and efficient waste disposal systems resulting in the pollution of waterbodies in Kochi.
“The local bodies close to the Periyar lack proper sewage treatment plants. Moreover, the closure of the Pathalam bund in summer to check saline water intrusion often restricts the normal flow of water in the river. Heavy loads of organic and inorganic waste then get accumulated in the upstream region of the river affecting the normal ecology of the river system,” he said.
Charles George of the Matsyathozhilali Aikyavedhi said the spike in pollution levels in the Vembanad lake, which is listed as a Ramsar site, has impacted the aquatic ecosystem (Ramsar Convention is an international treaty for conservation and sustainable utilisation of wetlands).
“Eutrophication [sudden increase in nutrients in a waterbody leading to outburst in algae, floating plants, microbes etc.] has led to the reduction in oxygen levels in the Vembanad ecosystem. Many fish species need freshwater for spawning.
“The availability of many fish varieties has come down drastically owing to the increasing marine pollution,” he said.
Recalling how a waterbody like the Chilavannur lake had faced the brunt of urbanisation, C.R. Neelakantan, social activist, said a mafia involving landsharks and a section of bureaucrats had aided the illegal activities.
“How else will such nefarious activities continue unchecked?” he asked, referring to the recent attempts to encroach on the waterbody, which is part of the Vembanad backwaters. The Chilavannur lake extends from the Chettichira bridge on Subhash Chandra Bose Road in the Kochi Corporation to Irrigation Bund Road in Maradu municipality.
Maintaining that the waterbody had turned stagnant owing to large-scale human interference, Mr. Neelakantan said the natural flow and tidal exchange in the lake had been restricted by artificial constructions, siltation, and indiscriminate reclamation.
“While waste remains a burden for those responsible for generating it, it is a gold mine for those who make money out of it by agreeing to collect it from the source of generation. They dump sewage from various households and establishments and discharge it into waterbodies. Nowadays, large quantities of solid and construction waste are used to reclaim waterbodies,” he added.