Fairfax County will commit more than $500 million for subsidized housing in Tysons Corner but has yet to figure out how to pay for transportation and other infrastructure, a Republican supervisor said Wednesday.

Supervisor Pat Herrity (Springfield), returning to a theme that has triggered the most persistent and heated clashes on the Democratic-led board, said the county should reconsider policies that require developers to contribute to workforce housing and other initiatives that he deems nonessential. These include the push for environmentally friendly building design and mass transit incentives, known as Transportation Demand Management plans, or TDMs.

Instead, Herrity called for a return to the days when developers shouldered the expenses of transportation infrastructure in exchange for county approval to construct more dwellings, offices and stores on a site.

“We’re putting a half-a-billion dollars into subsidized housing for people making $70,000 to $120,000 a year instead of handling a lot of our most important priorities, such as transportation in Tysons Corner,” said Herrity, who outlined his views in an interview and a newsletter to his constituents.

Herrity and other Republicans have argued that the county should not be subsidizing housing while struggling to maintain public services and minimize tax increases. He has been especially critical of workforce housing subsidies for families that earn as much as 120 percent of the area median income, which is set by the federal government and is now $107,500 for a family of four.

But supporters of such initiatives, including Chairman Sharon Bulova (D), argue that affordable housing initiatives cost taxpayers little but return substantial benefits. Providing affordable housing for teachers, firefighters and low- income families means that fewer of those workers will jam the roads commuting from less expensive homes in neighboring jurisdictions. Segregating lower-income people into enclaves can also concentrate some of the problems associated with poverty.

“Pat’s objections are beginning to sound like a broken record,” Bulova said Wednesday. “It looks like a not very scientific analysis of what the costs are for housing in Tysons.”

Herrity and his staff calculated the costs in part on the county’s requirement that at least 20 percent of new dwellings in Tysons Corner to be set aside as workforce housing. Herrity also factored in a developer’s testimony that his firm would pay $27 per square foot to comply with a variety of county initiatives.

As a result, Herrity projected that Tysons Corner developers will ultimately kick in an estimated $2.2 billion for affordable housing, green roofs and mass transit incentives.

Using data from the Georgelas Group’s project, Herrity said the cost of providing workforce housing alone amounts to about $3.5 million for each of five residential buildings, or about $8 per square foot. Extrapolated for the rest of Tysons Corner, Herrity and his staff said the cost would be nearly $384.6 million.

Using similar calculations for commercial properties, Herrity said those developers will contribute an additional $102.5 million, or about $3 per square foot. Those estimates do not include the loss of an estimated $70 million in potential revenue because subsidized housing units are taxed at less than full-market value, Herrity said.