Demolition of the main wing of Saint John’s Health Center in Santa Monica began Tuesday, February 15th.

The Sisters of Charity of Leavenworth built the main wing more than 60 years ago.

“Although we will be demolishing the original main wing, we will certainly be keeping the spirit of Saint John’s and our strong commitment to the community,” said Bruce Lamoureux, hospital president and chief executive officer.

The demolition process, which will take up to four months, is the next step in a major redevelopment of the hospital after the 1994 Northridge earthquake caused significant damage.

A four-story, 275,000-square-foot Howard Keck Diagnostic and Treatment Center will be built on the main wing site.

After demolition, construction of the Keck Center will begin this summer and is expected to be completed in 2009.

When construction is complete, the Keck Center will be connected to the hospital’s North Pavilion, a new 182-bed inpatient facility that opened in December.

Hospital officials said the main wing will be demolished one floor at a time and disruption to patients will be “minimal.”

Hospital and medical building parking will be unchanged. The patient drop-off point at Arizona Avenue and 22nd Street has been closed.

A patient drop-off and pick-up site has moved to two locations on Santa Monica Boulevard — at Denny Court and a valet parking area west of 23rd Street.

Funding to build the Keck Center comes from the W.M. Keck Foundation.

The Keck Center will house the Weingart Foundation Emergency Department, Thomas and Dorothy Leavey Foundation Radiation Oncology Center, the Mrs. Henry E. Singleton Express Diagnostic Center, Vasek Polak Cancer Center and the Joyce Eisenberg Keefer Breast Center.

The Keck Center will also house a new surgery center, imaging department and cardiac catheterization laboratories.