Call for guidelines for conservation of freshwater sources
KOCHI: Conservation of canals in Kochi has gained importance, with studies showing that major freshwater bodies in the region are polluted by urban waste.
The Mullassery, Thevara and Perandoor canals, the Karanakkodam, Koithara, Edappally, Changadampok, Kharee, and Puncha thodus and Poorni puzha have been so polluted, heavily. Freshwater sources, such as Adimuri thodu and the western half of Edappally canal, are also heavily polluted.
A study, conducted by School of Environmental Studies of the Cochin University of Science and Technology, found that human interference was one of the main reasons for pollution of these water bodies.
Untreated sewage was dumped in these canals. Rapid urbanisation had affected the ecosystem of these water sources.
The study found that with households having access to municipal water supply, water from the Periyar ended up in the canals in a 'denatured form.'
Canals had little water-holding capacity owing to the pressure of land development. Edible fish had been wiped out by prolonged bouts of hypoxia. The freshwater part of the canals was severely polluted, following indiscriminate raw sewage discharge.
The study report said these canals were also considered mosquito nurseries in the city. Investigators who participated in the study found that huge quantities of waste from slaughterhouses were dumped into the Edappally canal and the Karingachirapuzha.
The study recommended that a system be developed to collect and compost waste from slaughterhouses and fish markets. Experts found that local water resources would have to be developed in tune with the upland development of the Greater Kochi region.
They urged the authorities concerned to evolve guidelines and regulations for conservation of freshwater marshes. The study suggested that land management and on-site waste disposal be initiated to conserve canals in Kochi.
It pointed out that an enormous political will was required to restore the canals to their original form. Transformation of a sewage conduit to a freshwater canal would demand a psychological rehabilitation and a cultural mobilisation among the public.
Kochi would not be able to survive the extinction of tidal canals.
The topography of the city was such that there were alternate sand bars with a swale in the middle.
If the greed for land ate into natural drains, the city would have to drown in its own liquid wastes, as the natural gradient is not conducive to a swift and efficient discharge of the runoff, the study said.