After three years of talking, developer Nick Podell says he’s ready to start building some housing at 20th and Bryant streets. Whether he’ll get to do so is not certain.

Podell has redesigned his so-called Beast on Bryant project four times to try to satisfy neighborhood opposition. He is headed to the Planning Commission on Thursday for a showdown over what would be the Mission District’s largest housing development: a 338-unit complex that would surpass Valencia Gardens, the 260-unit public housing project on Valencia Street.

First proposed in 2013, the Bryant Street project faced early opposition from groups of makers, performers and artists who had long worked on the property. Criticism of the project has focused mostly on the impact market-rate projects would have on a neighborhood where gentrification is rapidly squeezing out Latino families and artists.

Podell’s lastest proposal at 2000-2070 Bryant Street calls for two brick-clad buildings separated by a public alleyway. On the north side of the block would be 196 market-rate rental units, plus three affordable units to replace rent-controlled units that are being removed. On the other side would be a 139-unit, 100 percent affordable development, for which Podell has offered to donate the land, valued at $22 million. His company would not build those units.

In addition, the project calls for 18,000 square feet of space for artists, retailers and PDR uses — production, distribution and repair — that would replace about 50,000 square feet of such space that is being lost.

Podell said it is unprecedented that the affordable housing units will represent more than 40 percent of the total in a development that is not asking for any zoning changes, such as added density or height. Originally, Podell had proposed a 274-unit development with 16 percent of the units — about 44 apartments — affordable to low-income families.

“That was the No. 1 thing we heard from the community — maximize the amount of affordable housing,” said Podell. “Out of all the issues, that really bubbled to the top.”

Indicator for other projects

The Bryant Street project could be a bellwether for three other market-rate Mission District housing projects in the pipeline: the so-called Monster in the Mission at the 16th Street BART Station, which has been stalled by litigation between the property owner and the developer; the 157-unit project Lennar is proposing at 1515 South Van Ness; and Axis Development’s proposed 117-unit project at 2675 Folsom St.

But in the Mission District, which is in the midst of a contentious race to replace termed-out Supervisor David Campos, the latest version of the “Beast” is hardly being met with universal support. Instead, it has become a litmus test for how the various candidates for supervisor would handle an affordable housing crisis in a neighborhood that is arguably gentrifying faster than any other in San Francisco.

All three of the top candidates for the seat have carved out positions on the Bryant Street project. Candidate Hillary Ronen, an aide to Campos, says she supports the proposed land dedication but wants to see Podell contribute money to help pay for the affordable housing.

“This is the only market-rate project in the pipeline that would lead to something great — the creation of 139 affordable units at a time when we are facing the biggest affordability crisis in history,” Ronen said. “I think it makes a lot of sense, but I think he could do more.”

Affordable units

One of her main opponents, attorney Josh Arce, is part of a Build a Better Beast coalition pushing for a project that is more than 50 percent affordable and replaces — one for one — the 50,000 square feet of arts and PDR space being eliminated. Arce, who is community liaison for Laborers Union Local 261, which generally supports market-rate development, says the city’s building trades unions would be willing to invest money in the project to help pay for increased affordability and space for blue-collar businesses.

“Community, arts and labor leaders are ready to invest their own resources to build more affordable units and build them earlier,” Arce said. “This is the first time you have folks coming together to put resources into a project, and the developer has declined to talk to us.”

Boe Hayward, a spokesman for Podell, said that “no project alternatives have been shared with the project team and as a result, I am unable to respond.”

Podell said, “Every time we try to accommodate everyone, they ask for more. We go to 40 percent and they want 50. We are proud of this project the way it stands.”

A third candidate, Edwin Lindo, one of the Frisco Five that staged a 17-day hunger strike while calling for the firing of Police Chief Greg Suhr, is also supporting the Better Beast scenario.

Critics argue that because the affordable units are not yet funded, there will be years of delays before they are built and that both the buildings should be constructed simultaneously.

Funds available

Jeff Buckley, who heads up housing policy for Mayor Ed Lee, said the city has the money needed to pay for the 139 affordable units. He said the Mayor’s Office of Housing and Community Development is ready to solicit proposals from affordable housing nonprofits as soon as the Beast on Bryant is approved by the Planning Commission. He said the Bryant Street project will not require money from the $310 million affordable housing bond voters passed in November.

“The reality is that we have funds available for the site,” Buckley said.

Tim Colen, executive director of the Housing Action Coalition, which advocates for residential development, criticized opposition as “idealistic purity at the expense of practical solutions.”

“I am flabbergasted that there is a group of folks who would rather turn down 139 affordable units than support a single market rate unit,” said Colen.

J.K. Dineen is a San Francisco Chronicle staff writer. Email: jkdineen@sfchronicle.com Twitter: sfjkdineen