Developers of a proposed northwest Lawrence shopping center have plans to make it bigger in an effort to attract a home improvement center and a discount department store.

City commissioners at their meeting Tuesday will consider a rezoning request that would allow for an additional 175,000 square feet of retail space to be built at the northeast corner of Sixth Street and the South Lawrence Trafficway.

The development group — which includes Lawrence businessmen Duane and Steve Schwada — doesn’t have a deal yet, but it believes a home improvement center and a discount store are the most likely tenants for the development.

But the plans already have hit a snag as the Kansas Department of Transportation is expressing concerns about adding a new curb cut and right-turn lane on Sixth Street to accommodate traffic from the development.

“We believe operationally the road would continue to function well with a right-in and right-out access point, but we’re going to have to have more discussions with KDOT about that,” said Scott McCullough, the city’s director of planning.

KDOT engineers have expressed concern that allowing the new curb cut could create a precedent for multiple access points to develop along West Sixth Street, much like they have on 23rd Street.

It wasn’t immediately clear whether the right-turn lane issue could jeopardize the project. Attempts to reach a representative with the development company on Monday were unsuccessful.

KDOT leaders essentially have the final say on whether the right turn lane — which would be between George Williams Way and the South Lawrence Trafficway interchange — is allowed. That’s because Sixth Street also serves as U.S. Highway 40, which means new access points must be approved by the state.

The city could take over regulatory control of Sixth Street, but that would mean a significant loss of revenue for the city. The state provides the city about $3,000 per lane mile each year to maintain Sixth Street, McCullough said. That money would be lost if the city took the road out of the state’s regulatory system.

Commissioners on Tuesday will be asked to approve a rezoning request and preliminary plat for the property despite the uncertainty surrounding the access issue.

The project — dubbed Mercato — already has been approved to house about 185,000 square feet of retail space on the northeast corner of the intersection of the South Lawrence Trafficway and Sixth Street. The proposed rezoning would allow that amount to grow to just under 360,000 square feet.

City planners are recommending approval of the rezoning request because they said the request will still keep the intersection below the 400,000 square feet of commercial space that planners have set as a maximum for the interchange.

Developers are asking for the additional square footage after a development plan for the southeast corner of the intersection expired without being built. That development — called Northgate — was approved for about 195,000 square feet of commercial space. Developers of Mercato are requesting that the bulk of the retail space set aside for Northgate now be added to their project.

McCullough said his office has studied the proposal, and has determined it likely will not be detrimental to the downtown retail market. That’s in part because two large big box stores are the most likely tenants for the new development.

But the rezoning does not commit the developers to marketing the site only to home improvement stores or discount retailers. Any number of retailers could end up at the site. McCullough said the city is reserving the right to re-study the proposal if the types of tenants end up changing significantly.

A timeline for the project to begin construction isn’t known. The developers previously have said they won’t begin construction until they have found a tenant.