Mystic - For nearly half a century, the white colonial house with an addition has been a place that 25 adults, many suffering from mental illness, have called home.

To keep the facility open, however, the proprietor of Mystic River Residential Care, Elaine Cole, will appear before Groton's Planning Commission tonight asking for permission to start a much-needed renovation.

When she purchased the facility, Cole entered into a consent agreement with the Connecticut Department of Public Health to bring the building up to code. Since then, she said, she has tried to make the facility more like a home for the residents.

"I have variances from the health department, pending the build," Cole said. "It's not forever, though. We need to build."

The existing building uses nearly every possible space: a bathroom was turned an office, the maintenance equipment is stored on a staircase landing. There is only one shower and when the lines for the bathroom are too long, the residents must use one of two portable toilets located in the back of the building.

"We've done everything we could to accommodate zoning laws," Cole said. But to continue operating, she said she must renovate. Cole and her staff say the project has been met with opposition from some neighbors

"I think it's sort of the 'not in my backyard' mentality," said Leeann MacDonald, the facility's program coordinator. "But this facility, it's already been here for 50 years. We're just trying to make it better."

At tonight's meeting, Cole will present plans for a sweeping renovation and addition to the existing 10,000 square-foot building. With larger bedrooms, more bathrooms, and ample common space, the facility will better suit its residents' needs, she said. And the new building will fit better into the neighborhood, looking more like a house than an institution, she said.

The plan calls for the demolition of the two-story colonial house, built in 1895, that houses many of the residents, and the construction of a new two-story structure that takes advantage of the lot's slope to build into the ground instead of requiring a second story. The new building would be 14,700 square feet, about 50 percent larger than the existing structure.

To move forward with the project, Cole is asking the Planning Commission to grant a "reasonable accommodation" of the construction, arguing that residents have a right to live in better conditions.

"Our population is disabled and they are entitled to live in a home," Cole said. "With this plan, we've done everything we could to accommodate zoning laws."

Cole was denied a permit to construct a one-story addition from the Zoning Board of Appeals in 2007, but she hopes that this year her plans, which call for more significant changes to the facility, will move forward. But opposition from some neighbors could set the work back, or prevent it altogether, she fears.

"There are some neighbors who feel very strongly against this building," Cole said. "But this project is coming from a need and the law. The health department says you can't keep people in this condition. And I agree."

The Planning Commission meeting begins at 7 p.m. at the Town Hall Annex.

m.collette@theday.com