The financial capital has been the worst-hit by the deadly coronavirus, reporting more than 60,000 infections and 3,170 fatalities so far.
The second phase of the hospital was completed in 17 days. It has 100 beds with ICU services, while the other 900 are divided into oxygen and non-oxygen facility equally.
Maharashtra Chief Minister Uddhav Thackeray virtually inaugurated the facility, which has been handed over to the Brihanmumbai Municipal Corporation (BMC).
Mumbai Metropolitan Region Development Authority (MMRDA) had handed over around 1,037 beds with ICU facility to the BMC in May-end.
The first facility had weathered the Nisarga cyclone which passed the Mumbai coast on June 3, but as a precaution, over 150 coronavirus patients were shifted to another location.
While the first phase of the hospital was made for non-critical COVID-19 patients, the second phase will be treating critical symptomatic patients.
The COVID-19 hospital, set up along with Jupiter Hospital, also has a pathology lab with facilities for blood tests, an ECG machine and other testing equipment along with rooms for doctors and nurses.
"We are happy to set up this mega health care centre at BKC for the treatment of COVID positive patients. It gives me immense confidence that we were able to do our bit in this critical time of pandemic," Metropolitan Commissioner R A Rajeev said.
According to MMRDA, the makeshift hospital has been constructed using German tent technology, and the structure is designed to be waterproof.
"MMRDA has taken utmost care of the usual flood lines of the area where the hospital is being constructed. Interestingly, even during danger of cyclone Nisarga the previously constructed Phase-I Covid care centre at BKC remains unaffected," Rajeev added.
The authority further said more than 500 patients are receiving treatment in the first phase of the COVID-19 care centre and nearly 30 patients are being discharged everyday.
The authority has spent Rs 19.01 crore for the first facility, while the cost incurred for the second facility is yet to be ascertained.
Global private equity firm Blackstone has provided financial assistance of Rs 1 crore for this facility to buy medical equipment, the authority said. PSK ABM ABM