As the rains have now replenished the once drought-stricken Rajanganaya reservoir, its water quality has however become compromised by an unidentified algae-like growth, turning the valuable water resource a bright green, and a horrid stench wafts through the area causing great discomfort to villagers. While the reason for the contamination is yet to be identified, residents in the area are expressing concern about the suitability of the water to be distributed as drinking water and its possible health hazards.
According to Terrence Gamini, a farmer from Rajanganaya Block 4 and President of the Saliyawewa Rajanganaya Farmers’ Association the issue is of great concern to farmers and other residents in the area. “There is an unbearable stench,” he said, adding that marine life also appears to have been affected. He likens the reservoir now to the highly polluted Beria Lake found in Colombo.
However, as the water continues to be supplied to the fields he says, the colour of the water being sent to the fields appears to be normal and odourless.
But the cause of the recent worrisome phenomena remains a mystery as two possibilities are being floated around. While some experts claim it could be a development of algae, others suspect it could be a form of bacteria, as old as three billion years.
Anuradhapura Director of Irrigation, Eng. Prasanna De Silva says, he suspects it could be a form of algae. “There is a lot of fertilizer use in the upstream,” he says, adding that the phosphate found in the fertilizer could be causing the growth of algae as increasing phosphate concentration creates a conducive environment for the phenomena to occur.
On the other hand, examining the situation, Senior Lecturer, Biological Studies Department, Rajarata University, Dr Wasantha Sena Weliange says, the issue appears to be an infection of a fast growing bacteria identified as ‘microcystins’ which prevents sunlight from penetrating the water while going on to reduce the oxygen levels in it. He believes, this is what is leading to the destruction of fish and plants in the water while creating a bad odour due to the lack of oxygen. According to him the main reasons for bacteria growth is the overuse of chemical fertilizers containing nitrogen and phosphorus. With only 5 per cent of the area’s farmers refraining from the use of fertilizers this could be a realistic possibility, farmer Terrence Gamini says.
If the contamination is the suspected bacteria, Dr Weliange has warned of possible health issues through its use, such as, negative effects on a person’s nervous system and liver. According to him, fertilizer use in areas closer to the reservoir may have to be altogether halted to control the situation.
Residents in the area are also expressing their worries regarding the ongoing potable water project which extracts water from the Rajanganaya reservoir to be distributed to other areas such as, Tambuttegama. “Even if it is purified can it be assured there will be no side effects” Gamini questions while also going on to question the now suitability of water from the Rajanganaya reservoir to be provided as drinking water to the public.
While officials from the National Water Supply and Drainage Board were not available for comment, Eng. Prasanna De Silva says, nevertheless there is no reason for alarm yet. “You can only see the growth in two locations spread across two hectares or so,” he said. He also claims there is no issue in using the water as distribution for agricultural purposes which continues as normal. “The odour has reduced as well” he points out.
According to him water samples have now been sent to the laboratory in order to identify the contamination while the results identifying the contaminative substance is yet pending. Until the tests identify the cause, it is a waiting game for the people of Rajanganaya to know of the disease that is plaguing their valuable resource and its possible effects on their everyday lives.