TWO STUDIES released recently by scientists at IIT Bombay aim to find solutions to the issues of crop planning involving a reservoir system and waste management in the city.
Crop planning can be done on the basis of the supply capacity and pattern of a reservoir system. Researchers R Arunkumar and professor V Jothiprakash have proposed a novel algorithm to help make a decision when systems with multiple components are involved.
“Optimising the operations of a reservoir in itself is complicated because of the uncertainty in the inputs, conflicting and competing objectives, etc. Multi-reservoir systems, with more number of variables to be optimised and large number of physical, technical, legal and social constraints are further complex,” explains professor Jothiprakash.
Multi-objective evolutionary algorithms start with an initial set of solutions, which are then allowed to ‘evolve’ under some conditions, a computationally tedious process. Here, the researchers have suggested the use of ‘chaotic algorithms’, which are very sensitive to changes in initial variables, along with a conventional multi-system evolutionary algorithm.
The researchers ran simulations using data from Kukadi Irrigation Project (KIP) in Maharashtra, a multi-reservoir system comprising five reservoirs, to test the efficiency of the modified algorithm. They used the algorithm to find optimal crop plan and water allocation in regions dependent on KIP for irrigation. They found that the solutions produced by their algorithm, even though only slightly better than the conventional algorithms in terms of net benefits, took fewer number of process repetitions.
However, this algorithm cannot yet be applied. “Real time reservoir operation is more challenging since we will need a system to predict the inflow in real time, along with the reservoir operation model,” says Jothiprakash. This study is a step in the right direction in the use of algorithms to help us design public policies and efficient systems, they said.
Another study has attempted to solve the challenge of waste management. Combining various waste management options, instead of dumping the waste in the open, can reduce the impact on our environment, suggested a study by Professor Munish Chandel, from Centre for Environment Science and Engineering at IIT Bombay.
“Statistics say that over 9,000 tonnes of municipal solid waste (MSW) is generated in Mumbai every day. Most of this ends up at two open dump sites and a bioreactor landfill in the city. Often, the waste is burnt in the open, and toxic pollutants from the fire have been known to cause respiratory problems, cardiovascular diseases and adverse birth defects. In addition transporting, handling, and disposing such a huge amount of waste results in the emission of greenhouse gases, fumes of sulphur dioxide and oxides of nitrogen (also called acid gases), particulate matter, and other toxic substances,” states the study.
However, there are many alternative scientific options available that prove to be better than open dumping.
Paper, plastic, clothes, and leather can be recycled. Kitchen waste can be turned into compost. Incineration – a method where organic waste is burnt and the inorganic residue turns into ash – can be used too.
Chandel has come up with a waste management scheme that integrates all beneficial methods. Using a method called life cycle assessment (LCA), a systematic way to estimate the environmental impact of any product, process or activity throughout its life cycle, he compared six different combinations of integrated waste management scenarios, with the current method of open dumping in a landfill.
They considered scenarios where different proportions of waste were directed to recycling, composting and anaerobic digestion (degradation in the absence of oxygen), based on the composition, recyclable portion and type of waste.
The results of the study show that there is no single MSW management scenario that performs best in all the impact categories. In addition, the researchers found that even if the waste was dumped in a landfill, recycling some of it could significantly decrease the impact on the environment.