Green Bridge Technology: A simple solution for sewer and waste treatment
A simple technology most microbiologists would know of, has now been used on a much larger scale to clean parts of River Ahar which had become a sewer drainage canal leading to Udai Sagar Lake in Udaipur. The river had become so toxic with industrial waste that all fish had died and it was filled with foam several feet high. The toxic waste had seeped into ground water and was polluting the farms nearby – foam would come out while pumping out water.
The Green Bridge Technology developed by Shristi Eco Research Institute (SERI), a Pune based company, was used by Jheel Samrakshan Samiti, a people’s organization, to clean 700mtrs of the Ahar river just before it reached the lake. In an inspirational example of people’s involvement and participation, JSS implemented this technology with labour support from affected village communities and donations from individuals, corporate and government.
The technology involves building alternate inverted-V shaped stone structures across the given length. The inverted V is covered with cloth made of coconut husk. A mix of microbes and bio-chemical solution is then poured into it and covered again with coconut husk. The water flowing through these structures carry the solution down the river cleaning up all heavy metals deposit in it. Cannas are planted on both the banks of the river which acts as natural sponge for sewage and waste.
Within two months, the dissolved oxygen rose from nil to 6.9ppm resulting in a return of aquatic life. The acidity level decreased from ph level 10 to 8 and fecal coliforms decreased by more than 80%. Now animals can be seen drinking water from the canal and birds feeding on fish and other organisms. Farmers are happy that their water is not toxic anymore.
Simple and inexpensive solutions are at hand for our massive waste and sewer treatment problems, we just have to find the right answers.
Story as told by: Anil Mehta, JSS
Photo: Edgar Joshua V
Contact the Author: Bipasha Majumder