Kurt Walker likes seeing new restaurants popping up and white families with baby strollers walking along the street in his Wagener Terrace neighborhood, but he also fears that black residents are being pushed out as the neighborhood gentrifies.

Walker, who is black, inherited his Peachtree Street house on the Charleston peninsula from his grandmother and has watched the upper west side neighborhood change dramatically. The community had a large black majority - like the entire peninsula once - but it's now the most racially mixed neighborhood downtown.

Since the 1980s, there's been a stunning decline in the number of blacks living on the peninsula. Some neighborhoods - Wagener Terrace, Hampton Park Terrace, and Cannonborough/Elliottborough - lost roughly half of their black population in just one decade, starting in 2000.

Economic forces and demographic change - gentrification - are quickly transforming the upper Charleston peninsula. Those neighborhoods are the last downtown refuges of the middle class, and they have been increasingly attracting real estate investors, student renters, and affluent young adults seeking a more urban lifestyle.

The resurgence of urban centers is a national trend, readily apparent from Brooklyn, N.Y., to Portland, Ore. It's also a generational trend, a reversal of the "white flight" that saw a predominantly white middle class move from cities to suburbs in the 1960s.

In downtown Charleston, that trend has been picking up speed.

Ten years ago, half the single-family homes sold on the peninsula north of the Septima P. Clark Parkway (the Crosstown Expressway) sold for $170,000 or less. So far this year, half have sold for at least $325,000.

While home prices have been rising fast, much of the peninsula's population change is due to rising rents. Most peninsula residents are renters and the voracious demand from college students, who now account for about a third of the peninsula's population, has driven prices higher.

Downtown Charleston's relatively small number of homeowners - particularly longtime owners in the upper peninsula, who tend to be black - are solicited with real estate offers so frequently that some feel they are being pressured to move.

"Don't you ever come on my porch again or I'll call the police," Hampton Park Terrace resident Lesheia Oubre told one man who walked up to her front door with a note offering to buy her house.

Robert Mitchell, a black North Central resident who owns a house on King Street near Huger Street and serves on Charleston City Council, said he's advised constituents to post "no trespassing" signs.

"The people buying these houses are buying them as investments," said Mitchell. "They are coming to people who have had their homes for a while, and in these communities, those are African-American people."

Mitchell said his family sold his late father's property near Rutledge and Line streets to a cash buyer, who fixed it up and resold it. But Mitchell has no plan to sell his own house.

"The only reason I am still here is I bought this house in 1985," said Mitchell. "I get three calls a week from people asking to buy my house."

Around Hampton Park, strong demand for homes drove up the median sale price by $50,000 in just the past year.

"That neighborhood, it is on fire," said Carolina One Realtor Stephanie Wilson-Hartzog, who lives in Wagener Terrace. "It is back, and everyone wants to be there again."

Until the 1960s, Wagener Terrace was a white neighborhood in the still-segregated city. Peachtree Street, where Walker lives today, was populated exclusively by white residents in 1961, according to Nelsons' Directory of Charleston, which noted the race of each resident.

Black residents went to black schools and shopped in black shopping districts, such as upper King Street - now a trendy dining and shopping area with few older businesses left.

The schools were desegregated in the 1960s, the same decade when nearly half the white population vanished from the peninsula. It was part of the nationwide trend dubbed "white flight" wherein the white middle class moved, seemingly en masse, from cities to places such as West Ashley.

The post-World War II baby boom was in full swing, developers were essentially inventing the suburbs and the government was paving new roads to get there. Interstate 26, the Crosstown Expressway, and the now-demolished three-lane Pearman bridge between Charleston and Mount Pleasant were all built on the peninsula in the 1960s. These projects provided easier ways for people to commute but also tore through urban neighborhoods.

Now that the pendulum is swinging back, and more people want to live in urban centers, competition for limited amounts of real estate can be intense. In some ways, Charleston's peninsula is like a miniature San Francisco, or Manhattan; the relatively small center of a large and popular urban area, mostly surrounded by water, and increasingly expensive as demand exceeds the supply of housing.

There are about 5,000 single-family homes on the peninsula, a small number that helps explain why Walker has found photocopied notes slipped under his door mat three times offering to buy his home.

"If you are thinking of selling your house, I am a cash buyer and will pay you a good price for it," one note said, promising a $20,000 down payment and the balance whenever Walker decided to move.

Walker, a Burke High School graduate, said his grandmother bought the house in 1982. Like many black residents of this part of town, his house has been in the family for many years.

"Don't sell your mamma's home, it's the biggest investment you have," City Councilman William Dudley Gregorie often tells constituents.

Gregorie, a black former mayoral candidate who was a U.S. Department of Housing and Urban Development administrator, doesn't see anything sinister behind the big drop in the peninsula's black population.

"I think it's happening through natural economic forces," he said. "But I think we have a responsibility to make sure people who built it (the city) have a piece of it. Otherwise, we lose what the city is."

The more than 55 percent drop in the black population during the past 30 years was essentially the flip side of what happened during the previous 30 years, between 1950 and 1980, when nearly two-thirds of the peninsula's white population disappeared.

There are far fewer white residents on the peninsula today than in the mid-20th century - about half as many - but the plunge in the peninsula's black population since 1980 has been so large that in 2010, the population became majority white again for the first time in 60 years.

"The number of black families that leave aren't replaced by black families," Walker said. "It's a war of attrition."

One surprising thing, considering how crowded and busy the peninsula appears today, is that the total number of residents on the peninsula has been falling since about 1940 - not slowly and proportionally, but in large multi-decade declines involving one race or another.

"To me, it was the era of 'suburbanization,'" said Charleston Mayor Joe Riley, who grew up on the peninsula. "I think it was economic, primarily."

Many American cities were in decline - a quarter of Charleston peninsula homes were described as "dilapidated or no running water" in the 1950 census - amid urban crime and racial tensions.

As whites left the cities, black residents, who faced discrimination in real estate and lending markets, stayed behind and became the racial majority.

Oubre, who lives on Huger Street, said she remembers when the neighborhood in the 1960s included whites, blacks, Jews and Greeks. Oubre bought her house in 1964 for $10,000; it's worth $300,000 today, she said.

"But if I sold it," she said, "where am I going to live?"

Now, after two major, 30-year-long shifts in population and demographics, the peninsula appears to be embarking upon a third that could change the face of Charleston again.

After seeing the peninsula's population fall from 70,174 in 1950 to 34,636 in 2010, city officials expect a significant turnaround that could add perhaps 25,000 residents over the next few decades, mostly in the upper peninsula area that includes the East Central neighborhood.

"I hope and pray that this area becomes an area that people will admire and want to live in," said East Central neighborhood president Elizabeth Jenkins. "We want to shine, too."

However, Jenkins is worried. Previous efforts to improve the city, mostly in the 1960s, displaced many black families including hers, and those memories still sting.

"I hate to make it a racial thing, but it is," said Jenkins, whose family had to move when she was young to make way for Interstate 26. "Very rarely do you see major things that displace white people."

In the peninsula's black community, it's not hard to find people whose families had to relocate, and everyone seems to know a family that had to move at least once in the 1960s to make way for I-26, the Crosstown, the Pearman bridge, or the Gaillard Municipal Auditorium.

Colin Quashie, a nurse and artist who lives on Fishburne Street, uses blunt words.

"The targeting of African-Americans here on the peninsula, and the total white-washing of it, it's ridiculous," he said. "Don't we want integrated neighborhoods?"

Several neighborhoods where more than 90 percent of residents were black in 2000 are more integrated today, with more white residents. But some fear that current trends and rising real estate prices will transform these areas into neighborhoods like Ansonborough, Charlestowne, the French Quarter, and Harleston Village, where more than 90 percent of residents are white.

On the city's list of peninsula neighborhoods, the only remaining ones that are at least 90 percent black are public housing projects.

For homeowners, rising prices present economic opportunities, but for renters, it's a different story. Homeowners get more equity, more wealth, but renters get higher housing costs, and must pay or leave.

In Charleston, a key factor driving high rents and gentrification is college students.

The College of Charleston accounts for the largest share of students - a number that ballooned from fewer than 500 in 1968 to more than 11,500 in 1998, when enrollment leveled off. Add in the Medical University of South Carolina, which has no on-campus housing, and smaller institutions such as the Charleston School of Law, and a huge number of the peninsula's roughly 35,000 residents are college students.

College of Charleston owns or controls enough residence hall space for 3,221 students, who pay between $633 and $945 per month. The majority of students need to find apartments, and nowhere in the city is the law of supply and demand more forcefully at work than on the peninsula.

In search of lower rents, students have migrated north of the Crosstown and into the East Side. As a result, landlords are able to charge greater rent for houses in what used to be lower-income, black neighborhoods. A four-bedroom house might rent for between $2,000 and $3,000 a month in a neighborhood with a reputation for drug crimes and shootings.

"I sit out on my porch and I see (college students) walking by all the time, and I never saw that before," Mitchell said. "You see them walking on the East Side, at night."

Rachel Fowler, who is white and graduated from the College of Charleston in May, lives on Amherst Street on the East Side, paying $500 a month for one room in a three-bedroom house she shares.

She moved there in August from a four-bedroom house on Percy Street in Elliotborough, where she paid $700 monthly for a room.

Fowler said it's becoming increasingly difficult for students and recent graduates to find affordable living space on the peninsula.

"Just in my four years of college, rent went up $200-$300 a room," she said.

Fowler's building on the East Side is full of young people; the neighborhood now includes families and students, she said. She does not feel out of place.

The rents students are willing to pay are well above what many neighborhood residents were used to, and one consequence is that low-income families using the federal housing program known as Section 8 - officially the Housing Choice Voucher Program - rarely can find rentals on the peninsula.

In the voucher program, participants are allowed to spend only a certain amount on rent. For example, $1,026 per month is the maximum allowed for a three-bedroom rental. That wouldn't cover the rent on the house where Fowler lives, near a public housing project on the East Side.

"Going back about 20 years, it was pretty easy for people to find a place that was affordable, on the peninsula or in West Ashley," said Don Cameron, executive director of the Charleston Housing Authority. "Ten years ago, on the peninsula it was difficult."

He estimates that now, just about one-sixth of the roughly 1,300 low-income families in the voucher program live on the peninsula. The rest live elsewhere in the city, such as West Ashley, or outside the city limits.

"We don't have any area in the city, downtown, where rents have not gone up dramatically in the past decade," said John Liberatos, CEO of rentcharleston.com.

The good news for people with low incomes is the Charleston peninsula has more publicly owned subsidized housing than the rest of the tri-county area combined, enough to house about 6,000 of the peninsula's roughly 35,000 residents.

At public meetings, residents and advocates frequently ask if that low-income housing will be cleared away as the peninsula becomes more affluent. Several large housing projects are in or adjacent to areas that are being redeveloped.

Tim Keane, the city's director of planning, preservation and sustainability, said there is no plan to eliminate any low-income housing, and the city expects to create more. The city is also working to create more middle-income housing options, he said.

Ultimately, it's up to residents to decide where they want to live. Some longtime homeowners may simply want to downsize, and get a less expensive place in the suburbs.

"People chose to move for reasons that are up to them," said Keane.

But he said it's important that the peninsula continue to be a racially diverse place.

"Charleston is a city where African-American culture and presence is fundamental to what we are as a city, it's very much fundamental to the fabric of the town," he said. "If you lose that, you've lost something central to the character of this place."

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