Edina's 7500 York, which broke new ground 30 years ago as the nation's first senior co-op, is going to be a pioneer again.

The co-op and Ebenezer Management Services have just gotten the go-ahead from the city of Edina to begin construction of a four-story, 76-unit addition that will include assisted-living, memory care and short-term care suites. Officials think 7500 York is the first senior co-op in Minnesota to add extended care units that will enable healthy and independent seniors who buy into the co-op to stay close to spouses and friends as they age and experience memory or physical problems.

"They are really positioning themselves for the future," said Susan Farr, Ebenezer's vice president of business development. "Now they will have a full continuum of care."

The planned addition was approved by the Edina City Council on Tuesday in a 4-0 vote, with one member absent. If the project gets final approval by Ebenezer's parent organization, Fairview Health Services, construction could start in September. The building would open a year later.

The co-op, which will celebrate its 30th anniversary next week, is open to people age 55 and older. Though residents skewed toward the younger end of that scale when the development was new, people who buy into the co-op tend to stay put.

Today, the average age is 83, and living independently has become a challenge for some.

Couples have been split up as spouses left for nursing homes or assisted living. Those who had to move missed friends and familiar surroundings, especially in the winter, when co-op residents were more reluctant to drive to visit them.

"I have seen how hard it is for people to move out of this setting," said Lotti Matkovits, director of resident services at 7500 York. "So much is at stake, because this is a co-op. People contribute with committee work and help the community thrive. Then to have to leave it is heartbreaking."

She said it will still be hard for a spouse to move next door, "but they will be connected by just a walkway. ... Even if they are separated, they can have meals together. This will make a huge difference.

"So many residents tell me, 'I hope I can hang on until assisted living is there so I don't have to move far away from here.'"

The $17.4-million, four-story addition will include 47 units of assisted living, 16 units of memory care and 13 elder-care suites. It was approved by 75 percent of co-op residents who voted in March.

Though some residents resisted the project, saying it was inappropriate for a development that caters to independent seniors, those feelings have softened over time. Matkovits said one couple who opposed the addition now favor it after a health reversal, and are hoping the addition opens soon enough that they can take advantage of it.

Co-op residents will get priority at the new building, which will also have a cafe, movie theater with concessions, a Wii room with virtual bowling and other sports, a beauty salon and a library. The entire building will have Wi-Fi, and there will be a dining room, a gift shop, a screened porch and an outside area with seating around an electric fireplace.

The new building will be built to the northwest of the existing structure, away from gardens and paths that residents want to preserve. The roof of the co-op's underground parking garage will function as a plaza for the new building. While mature trees will have to be removed, Edina officials say that with new plantings and existing trees, the site will have more than three times as many trees as required by the city code.

The building, designed by Pope Architects of St. Paul, includes low-irrigation gardens, lights activated by motion sensors, underground storage of storm water and a layout that takes advantage of sunlight on the west and south sides of the building. Test wells are being drilled to see whether it would be economical to use groundwater for geothermal heating.

The council approved the plan despite a conflict with the city code. The provision appears to bar seniors from living in units small enough to be considered efficiency apartments. The council plans to fix the provision at a meeting in July.

Mary Jane Smetanka • 612-673-7380