AMHERST — Potential risks to existing businesses, including Amherst’s only full-size grocery store, and offering new housing mostly for area college students, are among concerns members of the Town Council are voicing over a proposed overlay zoning district for University Drive between Amity Street and Route 9.

With the Planning Board suggesting the zoning change to give more opportunities for mixed-use residential buildings and commercial development on the corridor that leads to the University of Massachusetts campus, councilors Monday, in advance of unanimously referring the matter to the Planning Board and Community Resources Committee so public hearings can be held, said they worry about losing Big Y Supermarket and the stores in that plaza.

“Amherst is a food desert, and I am concerned if we jeopardize that store,” said District 2 Councilor Pat DeAngelis, adding that it’s important the rezoning doesn’t encourage development of dorms for off-campus students.

“Is there a way to guarantee no dorms, and is there a way to protect Big Y?” DeAngelis said.

District 1 Councilor Cathy Schoen said both Big Y and the neighboring CVS Pharmacy are heavily used, but low-margin businesses. “Although we need housing, we also need to eat,” Schoen said.

Schoen said she would prefer to truncate the zoning district to protect those businesses, and the Goodwill Store, and fears that Amherst could lose viable businesses, similar to when Amherst’s only downtown supermarket, Louis’ Foods, moved to a different part of University Drive in the 1980s, becoming a Victory Supermarket in 1992 and then closing in 1999.

Senior Planner Nate Malloy said the rezoning proposal was put forward by the Planning Board in late June after discussions over the past year as part of a package of strategies to address the housing shortage in town.

“It’s to encourage mixed-use development, mixed-use by site plan review,” Malloy said. “The hope is to encourage infill here. The Planning Board thought this was an appropriate place.”

While the existing limited business and office park zoning designations on both sides of the street would remain, under the proposal 75% of the ground floor space facing University Drive and Northampton Road needs to be non-residential in use, ensuring a streetscape with shops. The proposal also calls for allowing developers to have a sixth floor on buildings, which would need to be stepped back from the facade, and flexible parking arrangements.

“It can be a mix of unit types for different tenants. They really want to have this be a denser area,” Malloy said.

There is also a chance that development could include multi-modal transportation options, with more bus routes and bike stations due to the proximity to both the state highway and the UMass campus.

Malloy said that with more housing, more people could walk and shop there. “We actually think some of those existing stores will become more valuable to prospective residents and tenants if this is built out,” Malloy said. “The idea is not to lose Big Y or those commercial areas, but to get more people using them.”

District 5 Councilor Bob Hegner agreed that preserving the existing shopping center is important. “If all we do here is provide dorms for students, then the mixed-use, the commercial we get there, is going to be providing services to students, not necessarily the community at large,” Hegner said.

“I don’t have a concern about developing this area, but I do have a concern if it only turns into developing college dorms,” Hegner said.

At-Large Councilor Mandi Jo Hanneke said she would have preferred to see the zoning proposal allow apartments, not just mixed-use buildings, and also would like to see an even larger district. But she questioned the requirement of requiring commercial on the ground level, and whether the 65-foot limit on height of buildings would even allow developers to have a sixth floor.

District 4 Councilor Jennifer Taub, though, said she would resist expanding the overlay district and appreciates the commercial mandate since the town needs more space for funky, boutique and unusual businesses, like the Hampshire Bicycle Exchange. Taub suggested that some of commercial space could be a “loss leader” for developers, in exchange for giving them the right to have the sixth-floor apartments.

“I think it’s very important that it remain mixed-use, all buildings, that it be a requirement,” Taub said.

Taub said she also wouldn’t want to see the Big Y Supermarket parking lot used for development, as it is usually quite full. “We can’t really sacrifice the parking that serves (the plaza),” Taub said.

Council President Lynn Griesemer said Big Y is one many Amherst residents and others use, and she wouldn’t want encourage people heading to Hadley to get their groceries. “It is the only large grocery store we have in Amherst,” Griesemer said.

Only one current development project would be affected by the rezoning plan. That 85-unit, mixed-use project at 422 Amity St. is going through Planning Board review after receiving a variance from the Zoning Board of Appeals. The development is expected to replace two one-story buildings on the site, the former Rafters Sports Bar and Restaurant at 422 Amity St., most recently a Pleasantrees marijuana dispensary, and the current Encharter insurance offices at 25 University Drive.

That has a mix of studios to three bedroom apartments, but Malloy said many developers are focused on buildings that only have singles and studios.

Other worries about what might happen with the rezoning include the parallel access drive along the west side of the street, to become a pedestrian pathway, which At-Large Councilor Andy Steinberg said could pose some risk to the the existing developments, like the post office and the Slobody Office Building.

Schoen noted University Drive is also a “sloggy area,” with wetlands that run to the west, mostly in Hadley, potentially hampering the size of developments.

Scott Merzbach can be reached at smerzbach@gazettenet.com.