Some I-485 interchanges see growth zoom, others languish – for now

Building a road changes more than transportation patterns. It lures and rearranges development. While many roads are expected to lessen congestion, often the new homes and businesses nearby only increase it. The first leg of I-485 opened in 1990. It was finally completed June 5. During those 25 years the population near many of the interchanges has soared.

When the first leg of Charlotte’s outerbelt highway opened in 1990, with two lanes in each direction, the county’s population was 511,000. “I think Charlotte was in the mood to grow,” says former Mecklenburg County commissioners’ chair Carla DuPuy, who served 1984-90. “People were anxious for development. We wanted to be a bigger city.”

Charlotte got its wish. When the final segment of the 67.6-mile loop highway opened June 5, Mecklenburg County’s population had topped a million. The 10-county metro region includes some 2.5 million people. And a United Nations projection concluded that by 2030 Charlotte would be tied with Raleigh as the country’s fastest-growing city areas. And many of those new residents have clustered near Interstate 485.

I-485, the road that shape-shifted Charlotte

Charlotte’s I-485 lures growth, and with growth comes traffic

Today, the $1.325 billion I-485, after 27 years of construction, ranks as a significant catalyst for the growth in and around Mecklenburg. And it is around the interchanges, all in Mecklenburg, that the way local officials have handled growth pressures is most visible. Compared with the whole county, where the growth rate was roughly 100 percent, the population growth rate between 1980 and 2010 at some interchanges was more than 10 times that. The area near the interchange closest to UNC Charlotte, for instance, saw a growth rate of almost 1,300 percent. The area near the Rea Road interchange grew 1,100 percent. The population around the Johnston Road interchange at Ballantyne grew 755 percent.

Watch how population grew as highway expanded, 1980 to 2010

Map shows changing census tract populations 1980-2010. Scroll up to zoom in, down to zoom out.
Use hand tool to reposition map in the frame. Data: U.S. Census.

Most of the 34 interchanges remain comparatively undeveloped, offering local officials the potential for managing some of the urban sprawl the area has experienced.

“We’ve made good land use plans and policy,” says Assistant City Manager Debra Campbell, who oversees the planning and transportation departments. “I hope development occurs consistent with adopted policy.”

Today, fewer than a dozen interchanges are heavily developed, most in the southern part of Charlotte. Most of the interchanges on the east and west sides of the county are undeveloped. The towns of Matthews and Mint Hill control the land use at several interchanges to the southeast and east. On the west, plans are underway to encourage more development near Charlotte Douglas International Airport, but today municipal water-sewer is not available in the far west section of Mecklenburg County or in a section east of Mint Hill, which slows development in those areas.

“As a planner, you look out and see examples of good development but there also are lessons learned,” says Garet Johnson, assistant director who oversees long-range planning for the Charlotte-Mecklenburg Planning Department. “The successful places are the ones that have inspired a sense of community.”

Here is a look at population changes at some of the most developed interchanges. (* See note below about how population data were calculated.)

Exit 64/Pineville-Matthews Road-N.C. 51. In 1991, the regional Carolina Place Mall opened in the town of Pineville, inspiring further development at the outerbelt’s first interchange. With a rush of development on Pineville’s side of the interchange and in adjoining Charlotte, the area today is one of the most congested along I-485. The population a mile or so around the interchange increased 276 percent, from 1,433 in 1980 to 5,395 in 2010, according to the U.S. Census.

Exit 54/Johnston Road: Ballantyne. When the Ballantyne development was announced before construction began on the southern leg of the outerbelt, developer Johnny Harris described this planned community as “one of the most ambitious (developments) ever envisioned in Charlotte-Mecklenburg.”  Today, on nearly 1,800 acres of former farmland, it is a sought-after community of more than 4,500 residences, an office park, hotels and retail space. The population about a mile around the interchange ballooned to 14,335 in 2010, from 1,677 in 1980—a 755 percent increase. The developer donated 110 acres for relocating U.S. 521 through Ballantyne and for building the interchange.

Exit 59/Rea Road: Piper Glen and Stonecrest Shopping Center. Originally, an interchange wasn’t planned for this location, but after developers offered right-of-way, transportation planners agreed to move it. In addition to homes and apartments, the interchange features the popular Stonecrest Shopping Center and office buildings. Since 1980, the population a mile or so around the interchange increased from 693 to 8,314 in 2010—a 1,100 percent increase. South toward Union County, along Rea Road are an uninterrupted row of subdivisions, a shopping center and fast food restaurants.

Exit 1/South Tryon Street-N.C. 49: Ayrsley. Touted as the uptown of southwest Charlotte, Ayrsley offers a mix of homes, businesses and offices on 180 acres. Nearby around the interchange are a shopping center with several big box stores, including Wal-Mart, apartments and the still developing Whitehall Corporate Center. Population in the area grew to 14,802 in 2010 from 3,144 in 1980—a 371 percent increase.

Exit 21/Harris Boulevard: Northlake Mall. Opened 10 years ago, this regional mall filled a need for more and better shopping and dining options in the northern end of  Charlotte and Mecklenburg. Other commercial development sprouted nearby. The mall is surrounded by at least two shopping centers, one with a Target store, and fast food restaurants. Population roughly a mile around the interchange also has increased, from 918 in 1980 to 3,551 in 2010—287 percent increase. With the opening of the final leg of I-485, development is expected to accelerate.

Exit 33/University City Boulevard-N.C. 49: University City.  This interchange near UNC Charlotte reflects the university’s growth to more than 26,000 students. Within a mile or so of the interchange are hundreds of apartments and homes, as well stores and restaurants. Population about a mile around the interchange was 17,818 in 2010, up from 1,287 in 1980—an increase of 1,284 percent, according to the U.S. Census.

“The placement of the outerbelt made it more accessible for surrounding counties to have development. It ... is the reason they grew so fast." — Union County Planning Director Dick Black

Growth spills into nearby counties

In neighboring counties, especially in areas close to I-485, populations have soared.

  • Union County grew from 70,380 in 1980 to 214,568 in 2014, growing by 204 percent.
  • Cabarrus County increased to 192,103 in 2014 from 85,895 in 1980, growing by 124 percent.
  • York County, S.C., went from 106,720 in 1980 to 245,346 in 2014, growing by 130 percent.
  • Lancaster County, S.C., went from 53,361 in 1980 to 83,160 in 2014, growing by 56 percent.

“The placement of the outerbelt made it more accessible for surrounding counties to have development,” says Union County Planning Director Dick Black, who worked for nearly two decades as a planner in Mecklenburg County. “It really affected the surrounding counties and is the reason they grew so fast.”

When the first leg of the highway opened, state transportation officials say, they initially decided to build the highway with two lanes each direction based on local growth policies in the 1980s for the then-sparsely developed area. For a time in the 1980s, Charlotte and Mecklenburg officials had adopted policies encouraging large-lot, rural development and they restricted water-sewer line extensions beyond N.C. 51 in a short-lived attempt to curb suburban sprawl development.  But those policies quickly withered under developer pressure.

Today, says Warren Cooksey, a former City Council member now at the N.C. Department of Transportation, “We’re trying to find ways to avoid congestion.”  He adds: “This area is not finished growing.”


* Because census tracts don’t cover the same geographic area as I-485 interchange areas, to calculate population at the interchanges we tallied the population of every census tract in which part of the tract fell within a half-mile radius of the interchange. As a result, some census tracts we added cover a much larger area than just half a mile from the interchange.