It is surprising that fluoride was found even in surface water bodies like ponds, because fluoride is generally found in deep aquifers. Fluoride is a naturally occurring mineral in the deeper layers of rock beneath the earth's surface, so it was unusual to find it at such high levels even in surface water sources, leading to the conclusion that intensive agriculture in the area has spread the fluoride to the surface.
Outreach Project Campus in Madanapalle, Andhra Pradesh
The Arghyam – Outreach Project has been implemented in the village of Guttavarepalle in Madanapalle. Three different approaches have been used in the village to try and solve the fluoride problem: Rainwater Harvesting, Activated Alumina filters and defluorider sachets.
58 households in the village have also been assigned toilets through Nirmal Gram Puraskar (under the Department of Drinking Water and Sanitation's Total Sanitation Campaign), a government programme that will provide incentives for the construction of individual latrines in these selected households.
A defluoridation plant has also been sanctioned in the area by the government, which will cost approximately Rs. 9.4 lacs. This is in spite of the fact that defluoridation plants have proven to be quite ineffective mainly due to Operation and Maintenance (O&M) issues. In the process of sanctioning this plant, the villagers don't seem to have been consulted; their attitude is that if the government is doing something in their area, that is at the very least a good thing.
Fluoride and nitrate levels
First the drinking water was tested for fluoride, which was found to be very high, i.e. more than 3 ppm. The permissible level of fluoride is 1.5 ppm.
Then a nitrate test was conducted, where reagents A and B were put in the water. It was found to have nitrate levels of 25 ppm, which is within the permissible levels of 45 ppm.
Fluoride test results: higher than 3 ppm.
Nitrate test results: found to be over 25 ppm.
Jal Nirmal Defluorider Sachet
A defluorider sachet was put in the drinking water and stirred: it needs to be stirred every 10 minutes for an hour at least. 15 litres of fluoride-contaminated water was filtered through a muslin cloth an hour after the defluorider sachet was stirred into it, leaving fluoride residue in the empty bucket.
Jal Nirmal Defluorider Sachet: steps to follow to use the sachet printed on back
Stirring the defluorider sachet into 15 litres of drinking water from Guttavarepalle village
Fluoride residue left in the bucket after filtering the 15 litres of water
Villagers, Outreach and Arghyam staff filtering the drinking water
The filtered water was then tested for fluoride, which was found to be between 1.5 and 2 ppm which is slightly higher than the permissible level. It was therefore concluded that it is best to filter only 10-12 litres of water at a time with these defluorider sachets, in order to stay within the permissible fluoride levels.
These defluorider sachets cost about Rs. 6 each, once transportation and tax is included. The residents of Guttavarepalle village are willing to contribute Rs. 3 to the financing of the sachets.
As a part of this project in Madanapalle, Arghyam and Outreach have collaborated to construct individual Rainwater Harvesting Structures in 15 households within Guttavarepalle village. These structures were constructed last year, and are currently being used as storage tanks for borewell water as there has been no rain since they were constructed. They have a storage capacity of 4000 litres.
Rainwater harvesting structure constructed outside a house in Guttavarepalle village: currently being used for storage of borewell water
Hand pump in Guttavarepalle village
Another Rainwater Harvesting Tank being used for storage of borewell water
Arghyam and Outreach will assess the efficacy of Rainwater Harvesting with this coming monsoon, and see if the residents of the village are open to using it properly. The villagers will have to be shown that rain water will definitely be free of fluoride, or they will keep using the Rainwater Harvesting Structures as storage tanks.
Household Fluoride Filters
The third approach being implemented in this village is the provision of Activated Alumina fluoride filters in 28 households.
Activated Alumina household fluoride filter
These were distributed to households where:
- There were a higher number of fluoride-affected residents, particularly more children
- The house did not have space for a Rainwater Harvesting Structure
- The families were identified as poor and economically backward.
The water that was tested from these filters was found to have a fluoride level of 2 ppm. The problem that has arisen from this approach is that it costs Rs. 15 every 3 months to reactivate the chemicals inside the filter. The filter itself costs Rs. 2,000 to install and set up. The few households that are using these filters are only using the water for drinking; the residents said they wouldn't even use it for cooking. These filters have been brought to Guttavarepalle village from Kadiri, another area close to Madanapalle. The granule inside the filter was sourced from Mumbai.
It was agreed that there is still work to be done in order to identify the most practical solution to fluoride mitigation in the village of Guttavarepalle. The three approaches implemented so far each have their own pro's and cons. The most important thing to note was that Outreach has established a strong relationship with the villagers, who seem to be cooperative and ready to try new things.