It said there were no "slip ups" on part of the BMC employees but some locals had opened the manholes of the storm water drain.
The committee was constituted on the orders of Municipal Commissioner Ajoy Mehta to ascertain the cause of the doctor's death and find long-term solution to avoid such incidents.
The 36-page report, which was uploaded on the BMC's website today, said, amidst the heavy downpour, a few locals opened the manholes and left without covering it, which caused the death of Dr Amrapurkar.
The body of the doctor, who had gone missing on August 29 following heavy rains in Mumbai, was recovered the next day from a drain near the Coast Guard office in central Mumbai's Worli.
Dr Amarapurkar (58) had left for home on the evening of August 29 by his car but due to waterlogging on the road he asked his driver to drop him near the Elphinstone Road station and started walking towards his residence.
The doctor went missing while he was walking towards his residence when it was pouring heavily.
"The committee visited and recorded the statements of nearby residents who reportedly witnessed the incident and later spoke to the media. However, very few came forward to record their statements," the report said.
It said despite committee's repeated efforts to speak to Dr Amarapurkar's wife, she politely and firmly declined. According to the report, officials of a telecom operator also refused to share the location of Dr Amarapurkar, citing that they do not share such personal information with anyone except authorised police official.
"Police did not even share photos and other documents related to incident as requested by the inquiry committee," mentions the report.
It further notes that the committee's request to the dean of Sion Hospital to provide a copy of the post-mortem report along with histopathological report, was turned down by the hospital authorities, as police did not issue no objection certificate (NOC) to the hospital to share the report.
"The Assistant Commissioner of Police (operations), on request, shared the CCTV footage of August 29 between 2 pm to 7 pm, however, a tree is seen in front of the camera which obstructed the view of the manhole at the junction where the incident occurred," the report mentions.
"However, from another police camera, it is seen four to five locals unauthorisedly opening a few storm water drain manholes and leaving those uncovered. Another, CCTV footage provided by a shop owner also confirmed that these were the same people who uncovered the manholes," it said.
The report said footages from three CCTVs show a man crossing the junction of the Senapati Bapat Marg and SL Matkar Road fall in the manhole, which was opened without authorisation by the group of people who are seen in the footage of the police and one of the shops.
On September 1, a PIL was filed by the Federation of Retail Traders Welfare Association, Mumbai in the Bombay High Court seeking booking of BMC officials for causing the death due to negligence. It also sought a compensation of Rs 50 lakh for the family of the victim.
The High Court had expressed pain over the doctor's demise and had directed the BMC to file an affidavit on potholes and open manholes.