Editor's note: This story has been updated.

The decades-long Austin fight between those hoping to better accommodate the city's booming growth and those vying to protect the established character of existing neighborhoods has often pitted business interests against grassroots activists.

But now, there's a growing split between some neighborhood leaders over how the city should prepare for an expected influx of new residents. Some real estate and construction groups have chosen sides — and formed a seemingly nontraditional alliance.

Evolve Austin, which advocates for denser development, more viable transportation options and additional affordable housing, is set to announce Wednesday evening that it is partnering with several high-profile business organizations to champion a comprehensive development plan called Imagine Austin and a rewrite of land-use regulations called CodeNEXT.

“We see the cost of housing and the cost of real estate becoming a greater and greater negative,” said Drew Scheberle, a senior vice president at the Austin Chamber of Commerce. “The business community knows that part of the problem is insufficient supply relative to in-migration.”

The chamber is among business and real estate groups joining Evolve Austin, which started as a conglomerate of grassroots urbanist, social and neighborhood groups. Other new partners include the Real Estate Council of Austin, Home Builders Association of Greater Austin and the Austin Board of Realtors. They join existing partners that include Desegregate Austin, the Austin Housing Coalition and Alliance for Public Transportation.

“Really, our goal is to just sort of create a counterpoint to what the traditional sort of narrative in Austin has been for decades, which is greedy developer vs. neighborhoods,” said Andy Cantu, executive director of Evolve Austin.

Austinites don’t need help figuring out it’s getting more difficult to find an affordable place to live in the state capital. Or to point out that traffic is a twice-daily, frustrating exercise in attempted mobility.

And few Austin residents need to be reminded that they’re more economically segregated than those in other cities of its size or that the share of black residents dropped as overall population grew. What long eluded the city — which is far from alone in facing many of these issues — was a cohesive and executable plan to turn so many complex tides.

But after the City Council in 2012 adopted a comprehensive development plan called Imagine Austin, Evolve Austin emerged to champion the document as a guidebook for reversing several of the city’s most challenging trends.

“The way we arrange the city in its physical form has all these implications,” said Cantu.

The group has fought City Council attempts to water down key tenets of the plan and organized residents and businesses to support ordinance changes that follow in Imagine Austin’s calls for more compact development.

“There’s always this danger that it ends up sitting on the shelf,” said Roger Cauvin, an Evolve Austin board member.

The nonprofit has also since gotten behind CodeNEXT, the proposed changes to land regulations. The group sees that massive rewrite as the way to turn the vision of Imagine Austin into tangible reality.

The aim isn’t just to sell Imagine Austin and CodeNEXT to city leaders and residents. Evolve Austin also wants to change how discussions about the city’s continued growth and development are framed on doorsteps and at City Hall.

“To be a neighborhood activist, you don't have to be against new and diverse people in your neighborhood and new and diverse housing," Cauvin said.

Skepticism amid calls for change

While major business groups are signing on to Evolve Austin's vision, the organization's goals remain controversial among some more established neighborhood activists, many of whom have issues with Imagine Austin and CodeNEXT.

Mary Ingle is the president of the Austin Neighborhoods Council, a well-known group that advocates for several of the city’s neighborhood associations. She has made a name for herself as a City Hall watchdog. One of Evolve Austin's partner groups is Friends of Austin Neighborhoods, an organization Ingle said is "disruptive" and often takes stances that oppose those of her own neighborhood group. Ingle said she doesn't know much about Evolve Austin except "there aren't very many of them."

Ingle said CodeNEXT’s length of about 1,000 pages contradicts its characterization as being simpler than existing land-use rules. She also said its rules conflict with themselves in certain places and that she would expect an “almost perfect document” when the city spends millions on it.

“The citizenry of Austin would expect that, too,” she said.

Even ahead of today’s announcement about trade groups partnering with Evolve Austin, Ingle has been skeptical about the real estate industry’s involvement in influencing how the city grows.

“The city staff and the city government tend to bend over backwards for development and developers at the risk of the people who live here,” she said.

Protectionism or prevention?

Still, Ingle scoffs at any notion that the neighborhood group she leads is anti-development. She said she supports some projects, just not buildings “being slammed up” against existing neighborhoods to make money for developers.

Ingle was an advocate in 2004 for the creation of a special zoning district west of the University of Texas at Austin that would allow for denser development to provide more housing for students. Ingle said her neighborhood north of the campus and others around the school were being eyed as the perfect locations for multi-family student housing or buildings she called “stealth dorms” because they were “crammed” with students.

“We created a density node in order to take some of the pressure off our neighborhoods,” she said. “We kind of went beyond what at the time most people would have done. We knew there was a need.”

But Evolve Austin leaders say that older neighborhood groups’ opposition to new and different types of developments is often what prevents cheaper housing and smaller business spaces from being built in established areas. They say that, in turn, increases sprawl and traffic.

“Hundreds of thousands of Austinites want to call this special place home,” said Cantu, the Evolve Austin executive director. “Mary Ingle is not one bit interested in seeing that they have a decent place to live and work.”

"A new way forward"

Ingle and Evolve Austin’s leaders do agree on one thing: that a lot of the city’s new developments and growth aren’t done within the framework of existing zoning rules but by developers obtaining variances from current regulations.

Scheberle, the chamber executive, said that unpredictable process is slow and can drive up what developers spend to build, costs that can get passed on to buyers and renters. He said the rising costs of living and doing business in Austin are already making it difficult to lure new corporations to the city.

“The competitive advantage we had with downtown Chicago, if you can believe it, is gone,” he said. “It’s not a good thing, and it’s a self-created problem.”

Cantu said the union of industry and business groups with grassroots organizations highlights how different interests are coalescing around the idea that the way a city is built determines how much its residents thrive or struggle.

“Hopefully this is just the beginning of a new way forward,” he said.

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Disclosure: The Austin Chamber of Commerce and the University of Texas at Austin have been financial supporters of The Texas Tribune. A complete list of Texas Tribune donors and sponsors can be viewed here.