Backhoes and ground movers leveled part of 3M’s Maplewood campus Wednesday in preparation for the new $150 million R&D building that will replace two aging labs on the opposite side of the campus.

The state-of-the-art facility should be completed by fall of 2015 and is expected to house 700 existing scientists and researchers, said 3M Chief Technology Officer Fred Palensky while showing architectural renderings of the project for the first time.

3M began clearing land for the building last month near the corner of McKnight Road and Conway Avenue. The project will include a four-story L-shaped R&D center dedicated to technology research for three of 3M’s five businesses: electrical and energy, safety and graphics, and industrial. The 400,000-square-foot building will also be connect by skyway to 3M’s adjacent Healthcare Research and Development and Business Center.

“The primary focus here is to maintain the vitality of [3M’s] innovation and technology,” Palensky said. The idea is to create a place where scientists can share and collaborate on products, ideas and technologies from different sections of the company.

3M will eventually demolish one of the older buildings on the campus, but has yet to decide whether to raze or renovate the other, he said.

The cost of the new R&D center is about three times the size of 3M’s usual construction and renovation budget for its Maplewood campus.

The new building delighted Maplewood officials, who have sometimes worried that 3M’s rapid global expansion might one day prompt a move or downsizing. City officials supported a tax-increment-financing deal for the project, which the Legislature approved in May.

Maplewood Mayor Will Rossbach said previously that he learned of 3M’s new laboratory nearly a year ago and was “very excited” about the news. “It gives some assurances that when they are pumping more money into their campus that they are intending to hang around for a while. And we like that.”

3M generates 66 percent of its $30 billion in revenues outside the United States. But it also provides about 12 percent of Maplewood’s entire tax base, which makes it intensely important to the city.

While 3M has invested heavily in creating research centers worldwide — most recently in China, India and Korea — 3M officials have insisted that the United States remains the company’s innovation hub. 3M spent $1.63 billion in global research last year. But a good chunk of that was spent in Minnesota, officials said.

3M CEO Inge Thulin told shareholders and retirees at 3M’s annual meeting in May that he wanted the United States to remain the central head of 3M’s research and innovation. “Over $10 billion [in revenue] is here in the United States. It is the core” and will continue to be, he said.

The new R&D lab marks 3M’s latest investment in Maplewood. In 2003, 3M spent about $10 million renovating the exterior of its administrative Building 220 on the south side of campus.

Seven years ago, 3M built the 3M Innovation Center on the north side of the campus to showcase products, hold lectures and collaborate with clients. Last year, 3M renovated the interior of four administrative “quad” buildings, one of which includes Building 220.

The new lab will be known as Building 280.