BOSTON -- Amid fears that Massachusetts may not have enough hospital beds to handle an H1N1 outbreak this flu season, Beth Israel Deaconess Hospital unveiled a new multi-million dollar expansion in Needham on Saturday that will add valuable space to the state’s cache of medical treatment facilities.

The culmination of a five-year planning effort, BIDH-Needham’s expansion will add 20 private rooms and a brand new emergency department capable of handling 20,000 patients a year to the hospital.

On Thursday, a report released by the nonprofit group Trust for America's Health said that Massachusetts is one of 15 states that could potentially run out of hospital space if an outbreak of H1N1 flu spreads rapidly through the state.

Although BIDH-Needham is still waiting for final approval from the Department of Public Health to open the new $30 million wing, administrators said they’re prepared to use the facility to its full capacity if flu infection becomes widespread.

“We are ready to ramp up for surge capacity if we have a volume of patients that need to be admitted if they have the swine flu,” said Penny Greenberg, Chief Nursing Officer at BIDH-Needham.

The hospital, which services residents from Needham, Dedham, Westwood, Dover and Medfield, has an existing acute care hospital with a 41-bed capacity.

“We now have the most modern facilities in the area,” said Jeff Liebman, president and CEO of BIDH-Needham. “We also have many physicians who practice out here who have been trained at the academic medical centers downtown.”

Liebman said the hospital is hoping to begin treating patients at the new facility within the week.