Cleaning the Mithi

The technology available has been tried and tested. In addition to rejuvenating the ailing river,the MMRDA has also been working on reducing the level of pollutants to make the water clearer and odour-free. The authority has been using a pathbreaking microbial technology on a 3km stretch of the Mithi alongside the plush Bandra Kurla Complex since October last year. The technology,known as bioremediation,involves the release of microbes into the water to convert anaerobic elements to aerobic elements,enabling the sunlight to act as a natural disinfectant. With this experiment that costs Rs 2 crore a year,the level of pollutants in the water has come down by 90-95 per cent,and the presence of ammonia has been reduced by 68.4 per cent. However,experts say that the process will need to be continued until the time pollution is stopped at its source to make it effective.

Effluent treatment

Areas in Marol,Saki Naka and Jari Mari have a number of unofficial small-scale industrial units and scrap recycling units that discharge untreated toxic effluents straight into the river. These include units on the S G Barve Road Bridge in Kurla and near Habibullah Compound near the Air India Colony where chemicals,oils and other toxic waste are released into the river. BMC officials admit it is the civic body’s responsibility to keep a check on these activities but they have failed to do so despite having penalised these industries in the past.