To explain it too simplistically, if you shut off all pollution at source, like you shut off a tap, in flowing waters like a river, the river will cleanse itself in say a couple of weeks. Unlike the static waters of a lake which must be treated and quality restored, flowing waters need you to only stop polluting for the fresh charge of water to flush out the pollutants. We know, however, that is far easier said than done. The problem is complicated by our socio economic issues and cultural attitudes. But every long journey starts with a small step. We can reach the objectives only when we move ahead on the ground.Socio economic factors
The industries on the riverbank employ lakhs of people. Many of these industries have not learnt to operate in conformity to environmental standards for decades. It requires strong signals and penal actions from administration. Strong and drastic actions are not always locally popular. However, after an initial period of reaction and reluctance, I am sure industry will come around and learn to operate within the letter and spirit of the environmental objectives. It requires a change of mindset to understand that STPs and ETPs are routine everyday tools, there is no getting away from it, and these are not mere showpieces for an audit.
Attitude is another problem. On a social level, throwing trash into water is not frowned upon. The Government or the policing cannot be everywhere and all the time. Thus society as a whole, decides for itself, what each member must live with. This will take time to change, perhaps with more awareness and some soft policing.
The pollution levels increase as a percentage of content when the water tables or the denominator of this ratio is low. Debating the maximum carrying capacity of any water body in this century and age is unfortunate. We actually have no business letting any solid waste or untreated effluent flow into the waters and putting this ‘maximum carrying capacity’ to test. With the technology available today, clandestine discharges can be easily detected.
Shipping as an industry is well regulated with standard vessel construction rules i.e MARPOL. The net environmental effect will be negligible as compared to the large reduction in carbon footprints it offers. Riverside industrial parks with jetties are a great answer to bulk transportation needs. This removes the need for hundreds of trucks to move the same cargo on roads, thereby reducing congestion. Sustainability planning and strict compliance must go hand in hand with expansion of industrial activity.
Tourism needs pristine surroundings. We must get a handle on the progress of river cleanup and deal with the effect of religious tourism in the ghats, before expanding tourism industry any further. We must reach a stage where we value and enjoy clean waters. Waterfront and waterborne tourism will automatically boom.
Due to congested ghats, many ETP and STP infrastructure may not get the required land to be located on the riverbank. However, there are solutions to this problem. It is possible to locate barges, anchored close to the community that provide space and power, to set up these treatment plants. These barges can be moved around when land becomes available or priorities of location change.
Today most effluent levels can be monitored real time with sensors mounted on a floating platform that has power, data management and telemetry systems. These floating sensors ensure, you get a real time alert of pollution levels, on your mobile if need be. This can be the trigger to launch investigations and prosecuting actions. However these are tools available for the system and the machine is only as good as the man behind it.
The floating trash barrier is the most important component of solid waste management in rivers. Unlike boats, these barriers have practically no operating costs and have very low maintenance costs. They will trap and hold the solid waste 24 x 7 and bring it to the riverbank at the downstream end of the diagonally laid barrier across the river. It will do all this free of cost, utilizing the natural water flow of the river. The trash can be recovered from the riverbank regularly, manually or mechanically depending on the quantum of trash collected every day. These barriers need not be deployed all across the rivers since boat navigation must also be given space. Suffice to deploy it in small lengths immediately downstream of Ghats where waste is generated. The good part is these barriers can be redeployed to another location if there is change in pattern of trash generation or movement. Many Indian problems have very Indian solutions, Bangalore has a small tank within most major lakes for immersion of Ganesha Idols during Ganesh Chaturthi. This is an excellent Indian answer to an Indian environmental challenge. The whole process is well managed, considering that we are always talking of a large number of people in any such occasion in India.
Trash skimming boats also have some limited use. They burn fuel and thus have a reduced cost benefit as compared to barriers. The random trash floating in the middle of the river will come to the sides somewhere at a subsequent bend and it can be trapped here. It may not be necessary to burn fuel and send out the boat to trap these bits of trash. In locations where a high load of trash is to be found, the barrier can be laid to trap the trash and bring to the bank. (KNN/ Shekhar DC)