Mather LifeWays, one of Evanston’s largest senior care organizations, announced a $125 million plan Thursday to replace two of its existing buildings with a new retirement community.

The Mather LifeWays Board of Trustees decided Mather Gardens, 1615 Hinman Ave., and Mather Place at The Georgian, 422 Davis St., need to be replaced in order to remain competitive in the senior-living market, said Sara McVey, director of marketing for Mather LifeWays.

The organization, which is nonprofit and is one of the 10 biggest employers in Evanston, has invested more than $25 million in the buildings over the past 12 years, but the spending has amounted to “Band- Aids,” McVey said.

“Older adults are a lot more sophisticated these days in terms of the things they are looking for in a building,” she said.

Under the plan Mather Gardens will be the first building to close. McVey said there is no set date for the closing because the plan still needs to gain approval from the city.

Residents of Mather Gardens, an assisted living facility, will be allowed to move into any other Mather LifeWays facility while the building is under construction, McVey said.

“Basically we want to make this as easy as possible for our current residents,” she said.

The first part of the project is expected to open in 2008 at 1615 Hinman Ave. and the second half of the project is expected to finish in 2010 with a new building on the site where the Georgian stands.

The new development should be looked at as one community, McVey said. “We want it to be considered one continuum of living.”

The new community will include about 250 apartments for active seniors and about 50 suites for those who require more care.

The community will feature an indoor swimming pool, an improved fitness center, and multiple dining areas.

The Mather Pavilion at Wagner, 820 Foster St., will not be affected by the project.