Brihanmumbai Municipal Corporation (BMC) on Friday appointed a Swedish consultant for its Mithi River Water Quality Improvement Programme. The consultant, Swedish International Research Institute Limited, has also been appointed by the civic body to construct underwater sewage treatment plants in Versova and Malad. Both proposals, worth nearly Rs 47 crore, were approved by the BMC’s standing committee on Friday. The Mithi rejuvenation project, worth more than Rs 650 crore, is being implemented in four phases and BMC has proposed to spend Rs 21.90 crore on the consultant. There are around 40 places where sewage, along with garbage and industrial waste, is thrown into Mithi River, with no proper treatment. Civic officials said the Mithi rejuvenation project aims to stop the flow of sewage into the river by diverting it to the municipal sewage pumping station, where it will be treated. The consultant will coordinate between the contractors and BMC officials, provide expert opinion, and prepare timely review reports.