The Maharashtra Pollution Control Board has sought an explanation from the Dehu Gram Panchayat for the thousands of dead fish found floating on the Indrayani River last week. “We have sent a notice to the Dehu Gram Panchayat on Wednesday, directing them to submit their response about the dead fish incident within the next 48 hours,” said Dilip Khedkar, regional officer, MPCB.Mr. Khedkar further said that the MPCB would take action if the villagers failed to furnish an explanation for the incident in which around 4,000 fish, a majority of them being the Mahseer, were found dead.“The cause of this unfortunate incident was the release of untreated sewage, which resulted in the depletion of the oxygen levels in the river. We believe 2-2.5 million litres of untreated sewage were been released into the river per day by the village,” he said.The fish were spotted floating on the Indrayani River in Dehu, 30km from the city on Sunday last week, sparking panic among residents in the area.The dead fish included the mrigal carp or white carp fish, rated as ‘vulnerable’ as per the International Union for Conservation of Nature and Natural Resources (IUCN), and a large number of Mahseer fish, which holds significant spiritual value among the local people.“We have sent the collected water and fish samples for analysis and expect the results in a few days,” said Mr. Upendra Kulkarni, sub- regional officer, MPCB.According to Dr. Sachin Punekar, founder president of the environmental NGO Biospheres, the sub-standard rate of dissolved oxygen and eutrophication were likely to have caused the death of the fish.“The continuous inflow of untreated sewage from the Dehu village has resulted in depletion of dissolved oxygen. Foul play by individuals cannot be overlooked as well,” he opined.According to the MPCB officials, a sewage treatment plant (STP) with the capacity of 3 MLD (million litres per day) is expected to be constructed by the end of June.The construction of this STP will help treat the sewage and can also be used for irrigation and agricultural needs, said authorities. According to Dr. Punekar, the MPCB must take immediate action as the deteriorating quality of the river water could prove to be fatal during the upcoming ‘wari’(the annual pilgrimage to the shrine of Lord Vithoba in Pandharpur made by ‘warkaris’ carrying palanquins bearing footprints of the two saints).Meanwhile, the Zilla Parishad has banned the usage of water from the Indrayani.The Mahseer fish, known as the dev matha by the villagers, is said to travel along with the ‘Wari’ all the way until Pandharpur.This is not the first time that the toxic river has claimed animal or marine lives. Last month, 19 sheep allegedly died in Chikhli after drinking the waters of the Indrayani.