Scaling New Heights

Water Treatment in Pampa River – 12 Questions to Kerala State Pollution Control Board

Kerala State Pollution Control Board (PCB) has instructed Travancore Devasom Board to restart the addition of ferrous chloride to the Pampa River that is polluted during the Sabarimala season. The PCB claims that adding ferrous chloride reduces the coliform bacteria in water. A temporary dam is constructed across the Pampa river and ferrous chloride that is obtained as a byproduct during the manufacture of synthetic rutile is used for treatment purpose.

Having worked in the area of water treatment for all these years I should say that treating with ferrous chloride to reduce bacteria count is an unscientific method. I should agree with the statement of Dr Thomas P Thomas, a noted environmentalist and academician of Kerala.

The river treatment using coagulants only helps in the settling of the suspended particles in the sewage and not effective in reducing the coliform count in the stream. The coliform count can be reduced only by disinfection process which is not practical in the Njunangar stream as chlorine may react with organic compounds in the sewage to form substances which may be carcinogenic

If what I understand about the whole process is correct then it raises serious questions on the life of people and other living beings that uses this water downstream of the treatment process. It is the duty of the PCB to answer the doubts in the mind of people. After reading all the newspaper reports I have the following twelve questions to ask PCB. Hope someone gives me genuine answers to these questions and clear the controversies surrounding the whole treatment process.

1. Ferrous chloride is not a disinfectant. If killing of bacteria was the goal why was ferrous chloride selected and not a disinfectant?
2. Now if the goal was to settle out the bacteria why was ferrous chloride that is not a coagulant selected? Why did PCB not gone for a effective coagulant like ferric chloride or alum?
3. What is the purity of the ferrous chloride added for the treatment process?
4. What are the other constituents in the ferrous chloride added for the treatment process?
5. What is the detention time of the water in the temporary dam after the ferrous chloride is added?
6. What is the concentration of ferrous chloride, ferric chloride, manganese, zinc, nickel, chromium and other metals 100 meters, 500 meters, 1 km and 5 km downstream of the temporary dam?
7. How often does the sludge removed from the bottom and how do you make sure that part of it does not overflow through the dam when the removal process is taking place?
8. What other treatment methods were considered before PCB recommended adding ferrous chloride?
9. What happens if the water flow upstream of the dam increases (in case of a rain) and all the settled sludge overflows through the temporary dam?
10. What percentage of bacterial removal is achieved during the entire process?
11. Where does the sludge taken from the bottom of the river hauled to?
12. Does an independent agency ever verified any of your results?

I believe an organization as responsible as PCB should be answering all these questions in an open forum before going ahead with an unproven technology for removing coliform bacteria from water.

Labels: Kerala, Pollution, Water Treatment