The district fisheries department and Jharkhand State Pollution Control Board (JSPCB) are blamestorming over 300 fish dying a sudden death at the 700-acre Getalsud Dam, 30km from here. While the JSPCB, after a recce of the reservoir on Sunday, has claimed that there is nothing wrong with the water except for it being highly alkaline in a few places, the fisheries department on Monday shot a letter to steel wire manufacturing unit Usha Martin asking it to re-examine its effluent discharge system. “We have written to the company, seeking preventive measures at discharge point. A copy of the letter has been forwarded to the deputy commissioner’s office because he has the authority to take punitive action,” district fisheries officer Manoj Thakur said. Member-secretary of JSPCB Rajiv Lochan Bakshi, on the other hand, insisted that the fish might have succumbed to some endemic infection that had nothing to do with the quality of water. “Since the fishermen’s co-op alleged that the steel wire manufacturing unit was polluting the dam, we had collected samples from the outfall and other places. At the outfall, the pH is highly alkaline at 12.5, but in other places it is normal,” Bakshi said. The pollution watchdog said results of a few other tests such as turbidity was expected in two-three days. “On the basis of scientific studies, there is absolutely no issue with the water quality of Getalsud Dam. Once the full report arrives, it will be shared,” Bakshi stressed. “In fact, there seemed to be wounds on the gills, which the fisheries department needs to probe. Death could be due to some infection/disease. We don’t know,” he added. R.N. Kashyap, a pollution analyst and JSPCB regional officer, seconded Thakur. “Dissolved oxygen (3-5mg/l), pH value (6.5-8.5), biochemical oxygen demand (3mg/l), total dissolved solid (1,500mg/l), et al, are within range not just at Getalsud, but also other dams like Kanke and Hatia,” he said. Fisheries officer Thakur refused to buy that all is well. “The pH of Getalsud is as high as 12.5. The water is high on contaminants that are detrimental to fish health. We shall conduct our own studies once we get a formal report from JSPCB,” he said. According to experts, extreme pH can kill adult fish and invertebrates directly. It can also damage developing juvenile fish. Alkaline water is known to strip a fish of its slime coat. High pH level chaps the skin. When the pH of freshwater rises beyond 9.6, the effects on fish may include death, damage to gills, eyes or skin and inability to dispose of metabolic wastes. High pH may also increase the toxicity of other substances. For instance, the toxicity of ammonia is 10 times more severe at a pH of 8 than it is at pH 7. It is directly toxic to aquatic life when it appears in alkaline conditions. Low concentrations of ammonia are generally permitted for discharge.