The state is considering a revamp of I-375 that would raise a portion of the road to grade level and create a pedestrian-friendly boulevard designed to attract development.

State and local officials caution that the idea is not a foregone conclusion, just one idea that is being considered along with other options, including repairing the road in its current configuration.officials and local officials laid out the plan to begin a "community discussion" and study about the future of the roadway in an exclusive interview with Crain's last week.

If the study concludes the idea should not proceed, the state could begin making needed repairs to the corridor and its overpasses, which the state says are in poor condition.

There are a number of unknowns, including total cost; how many lanes, if any, would be reduced; what portions of the corridor would be raised up to grade level; and who would pay for it.

The approximate depth of the freeway in its current form is about 20 feet below grade.

There are no cost estimates at this point, because the state is not set on any one proposal, and wants to hear from the community about what it wants. But $80 million is the upward end.

"This is a significant piece of downtown Detroit," saidDirector Kirk Steudle.

The boulevard idea would make about 12 acres between Gratiot and Jefferson avenues available for development that the highway and rights of way now use, and that opens up potential for a public-private partnership to help pay for the project, Steudle said.

One idea to make that work would have the private sector invest in paying for the boulevard construction. In return, those investors would receive portions of the land that would be freed up. The premise is that given a reconfigured road system, that land and new boulevard frontage is more valuable. But Steudle said discussions have "not gone that far" in determining how the land would be divvied up among investors and who would purchase or obtain specific portions of the land.

"It can't be piecemealed," Steudle said. "This has to be a holistic process."

Since the repairs to I-375 in its current form would cost about $80 million, Steudle said he does not want to move forward with something to cost more than that. And right now, that is $80 million the state does not have, he said. One of the benefits of moving to a boulevard concept is that it would free up financial resources the state could use to invest in other roads around the state.

Action on moving forward with the plan will begin right away with the formation of an advisory board and possibly hiring a consultant. Steudle said the goal is to have a firm decision on what to do with the corridor by next spring.

After that, it would likely be 2015 or 2016 before construction begins, and construction would take about a year to complete, Steudle said.

"We're real anxious to get this process going," he said. "We don't want to spend money that doesn't fit into the overall scheme."

Several overpasses along I-375 are in poor condition and in need of repair, he said, and the state will continue with preventive maintenance to keep them safe until the outcome of the study is known.

"We're holding them together," he said.

Other cities around the country have done something similar to add boulevard stretches, including San Francisco, Portland, Ore., and Milwaukee. There are a variety of cities now considering such a move, including Cleveland, Seattle, New Orleans and New York City.

After observing what happened in those cities after such a switch, the state learned that property values increased, new development projects sprung up and access to waterfront was key in most of the changes, according to materials supplied by the administration.

Gov. Rick Snyder is aware of the project and is fully supportive of the idea, said his chief strategist, Bill Rustem.

This idea is an evolution of a freeway change idea from more than a decade ago.

Steudle said years ago there was a major push to extend I-375 two blocks to the waterfront, because at the time it was thought that was where the city's casinos would locate. That project was estimated to cost about $63 million.

In 2000, an environmental assessment was conducted and it found there would be no significant impact to the environment.

But since then, the casinos located elsewhere and the riverfront developed in a completely different manner, with more residential and retail locations, Steudle said, and the expansion never occurred.

Matt Cullen,president and COO, said at that time he was withand also chairman of the, and that he liked the idea then of bringing the corridor to grade level.

He said the current configuration makes it difficult to access the east riverfront and the Renaissance Center.

"I remain a philosophic fan of it," he said. "It would be much better for economic development, urban planning and city building if you could not have that thing cut the city in half."

Cullen said he would be supportive of "the idea of a beautiful boulevard coming into town, rather than this big ditch separating everything," but still needs to see the details of the traffic patterns to see if it could accommodate the amount of traffic.

The average daily traffic on I-375 ranges from 15,000 near Jefferson Avenue to 60,000 closer to I-75, state traffic data shows.

Not everyone is on board with the idea, a factor Steudle readily discusses.

He said issues have been raised both about the construction period and traffic pattern changes once construction is completed.

There are concerns about maintaining convenient access to theand the theater district during construction and ensuring that residents in the area can come and go conveniently.

And after construction is completed, access concerns remain as it relates to residents, fans coming to town on game days, and for moving in and out of Greektown and the theater district.

Another concern is whether the project should better tie into Eastern Market, Steudle said. Also, there will need to be discussion about where the transition will occur from highway to the proposed boulevard and whether that would begin at Gratiot Avenue or at another spot.

An alternate but similar idea -- bringing the highway to grade level at Lafayette Street and installing a traffic circle -- was part of the initial proposal but has already been scrapped because too many objected to it, Steudle said.

All of those questions and concerns and others are part of the discussion and study for the next year, he said.

"We want to start a conversation with stakeholders about what I-375 should look like," he said. "We are looking forward to opening it up further and wider and determine what that corridor should look like."

Regardless of the final outcome, Steudle said, a plan of some kind is needed because of the poor shape of the road.

"It's on its last legs," he said.

If the boulevard idea is agreed to in some form, federal input will be necessary because I-375 is a federal highway, and environmental permits would be needed.

Steudle said the plan wouldn't call for pushing the costs of upkeep onto the city.

"This is our asset," he said. "It will still be part of the national highway system."

If the city wanted to take ownership of it, though, it is something the state would consider, he said.

George Jackson, president and CEO of the, who will be at today's announcement, along with Cullen and Steudle, said the idea potentially opens up all sorts of development opportunities.

It's very rare for someone to propose an idea that creates 12 acres of developable real estate in a growing downtown, Jackson said.

"This gives us a real great opportunity to develop the riverfront," Jackson said.

But Jackson said the DEGC is not endorsing the idea and will wait to hear from the community and various stakeholders.

"There is not a preconceived conclusion," Jackson said.