Our urban centers have become like aquariums.
An aquarium is a closed system in which fish live, eat and poop. Many times the nitrogen produced via decaying poop and food matter gets converted to ammonia and the nitrate enriched water becomes a grave for the fish. Likewise, out urban centers without proper disposal of waste are becoming death traps for the residents and other living being.
Pudducherry (Pondichery), once known as the French Riviera of the East has luxuriant mangrove bordering the sea. Alas, the mangrove is facing the brunt of the urban waste from Pudducherry. Indian mangroves have already been plundered a lot and now we are left with only 2.66% of World’s mangroves covering about 4827 sq km land between the sea and the land. Mangroves are not only a transition between the land and the sea; they are also a nursery and breeding grounds for a majority of brackish and marine water fish and shellfish.
It need not be emphasized that all living being need oxygen and water to thrive. Water contaminated by sewage becomes a death trap for all the organisms. Sewage is mainly a liquid waste containing some solids produced by humans which includes soap rich washing water, faeces, urine, laundry waste and other material going down the drain from the households. It also includes all the industrial waste indiscriminately allowed to go down the drain to a river or allowed to reach the sea through urban drains.
The amount of sewage generated at Pudducherry is so great that a canal primarily meant for irrigation, now acts as a conduit to carry it to the sea. The government has set up treatment plants at Karuvadikuppam and Lawspet. Even now more than 30%sewage finds its way directly to the sea via the mangrove. The sewage treatment plant at Lawspet is not working properly, consequently untreated sewage flows through it and manages to reach the sea says a recent report.
Similarly Pudducherry produces about 120 tons of solid waste each day along with one ton of biomedical waste. Due to lack of proper landfills this waste is dumped in a low lying area adjacent to the mangrove. It is sad that the biomedical waste is burnt. Improper disposal of solid waste, particularly the biomedical waste is as good as committing suicide. Much of the waste lies on sandy grounds and during the rains leachates manage to reach ground water. The situation is complicated on that front too because much of the coastal ground water regime has been encroached by the sea water, which is now further polluted by the leachates.
Pudducherry mangrove occupies about 168 ha area along the flanks of Ariankuppam estuary which drains to the sea in the Bay of Bengal. Mangroves are woody trees and shrubs locally known as Sathuppu Nilakadukal say P. Satheeshkumar, U. Manjushaand N.G.K. Pillai of Central Marine Fisheries Research Institute, Kochi and D. Senthil Kumar of Kandaswamy Kandar Arts and Science College, Paramathi-Velur, India. The researchers claim that because the Pudducherry mangroves are endangered the local lesser communities are also at risk.
Since times immemorial mangroves have played a crucial role in the coastal economy. The mangroves have been used by our ancestors for many commercial activities like the use of wood of mangrove trees, fisheries, aquaculture and even salt production. In addition the mangroves have always stood like a solid wall to protect the coastal habitations from the vagaries of the ocean. Mangroves have always checked coastal erosion.
As the mankind has distanced itself from the nature, the human interference in the mangroves has considerably increased all over the world. In West Bengal and Bangladesh Sunderbans and their famous Tiger both are on the brink of extinction today, because of our greed. There was a time when the Sunderban mangroves were at their peak-read ‘Ancient Mangroves in the Womb of the Present’ . Geologists have collected sufficient evidence from the Sunderban that prior to human interference the mangroves were at their best.
In Pudducherry, alas, the human interference has reached a new dimension because of the discharge of urban waste. Several species of mangrove plants were identified by Sathuppu Nilakadukal et al.
Drinking water supply to Pudducherry is through Sunnamber lake reservoir. The urban waste is discharged into the mangroves. Enroute industrial effluents also find their way into this channel. The plant and animal species thriving in the mangroves range from fresh water to brackish water to saline waters. They are highly susceptible to environment changes. The urban effluents change the chemistry of mangrove waters and the susceptible flora and fauna are affected immediately. The shrimp farms on the coasts, close to the mangrove are another threat to the environment. Shrimps thrive in the saline waters, which is pumped from the sea into these farms. Sea water is heavier than fresh water. Soon it finds way to the groundwater reservoir and settles there. Though shrimps thrive in the farms, a large mass of humanity is deprived of fresh water.
It is time that the government acts and ensures that the sewage treatment plant operates properly and urban and industrial waste is not dumped in to the mangrove. The shrimp farms also need to be relocated and their tanks to be made impervious so that saline water does not penetrate the ground.