After a year of gearing up to tackle Denver’s affordable housing problem, city officials say they’re now ready to flesh out plans for a property tax hike and a new development impact fee.

Those proposals — which could be ready in the next month — would lean on anyone who pays property taxes or builds commercial or residential developments to contribute to the city’s $150 million, 10-year plan to subsidize more housing projects.

On Wednesday, the city unveiled a long-awaited study that officials plan to use as ammunition to justify the new development fees.

The “nexus study” looks at the link between different types of new commercial and residential development — from office buildings to hotels to apartments — and the need for housing they generate in the city by creating jobs. It was presented to a Denver City Council committee by the city economic development office and a consultant.

Though required before a city can create new impact fees, Denver’s new study confirms what economists already know: New development often tightens the housing market because those who fill the resulting jobs can’t always afford market rents or home prices.

Mayor Michael Hancock’s administration and City Council members have been working on the $150 million affordable housing plan for about a year. It would, over the next decade, draw on the new housing linkage impact fee — charged upfront on new development of many types — and the property tax increase.

The goal is to create or preserve 6,000 affordable apartments, condos and other housing units.

Specifications for the fees and property tax increase have not yet been pinned down, officials say. Tandem proposals likely will be unveiled in mid-July at a committee meeting and presented again at a July 21 public meeting at North High School. If passed by the council, both would take effect in 2017.

“Now that we have this information (in the study), we can get a better sense of which fees we are going to be aiming at,” Councilwoman Robin Kniech told reporters Wednesday before the committee meeting. “Then we can understand how much revenue that generates and then match that with the property tax that gets us to our minimum goal of $150 million over 10 years.”

Based on calculations by California-based David Paul Rosen and Associates, the nexus study finds that a typical new retail development in Denver creates an “affordability gap” for employees that would justify charging the developer as much as $120 per square foot as an impact fee to help offset housing pressure in the city. The study factors in average pay for those workers and that some would live outside Denver.

Other legally justified maximum charges would be $83 per square foot for a hotel, nearly $57 for an office building, nearly $29 for a warehouse, and closer to $20 for a 12-story condo tower or a 20-story apartment building, the study found.

Not that Denver would charge anywhere near that much.

Kniech said an analysis of how potential fee levels would affect the return on investment of various types of developments tested fees of up to $7 per square foot — the highest fee that she says might be proposed. Developers would be charged for gross square footage, which doesn’t include parking.

Similar types of impact fees long have been charged by large American cities, including Boston, while Colorado mountain towns and Boulder also have charged similar fees on new development. Even broader-based impact fees are more typical in suburban communities where new subdivisions require an expansion of roads, sewers and city services.

Denver’s housing-linkage fee, when it’s proposed, is likely to be lower than big cities typically charge, Kniech said.

“Most of the other cities that are comparable to us (nationally), they have fees in the teens,” she said. “By testing only $7 and below, we’ve already lowered the ceiling to a really moderate, modest level.”

Some developers have expressed an openness to paying an impact fee, and Kniech said several were consulted through an advisory group that met as the nexus study was prepared. But others likely will oppose it. And some free-market advocates argue that by increasing the cost of development, an urban impact fee will only raise market rents and home prices more, though other economists disagree.

But while the impact fee and any property tax hike could face push-back, some council members and housing advocates have argued that the city’s $150 million strategy is too modest to make enough of a difference in Denver’s housing market.

Hancock, who was traveling Wednesday, said in a statement that soaring housing costs for renters and buyers in Denver require the city to take action.

“Denver needs more affordable options for thousands of people who are struggling with the high cost of housing every day,” he said. “Our challenge is answering Denver’s critical housing affordability needs with new funding approaches that won’t stifle progress.”

The other funding source for the affordable housing initiative would be a property tax increase. Because of Denver voters’ approval in 2012 of Measure 2A, which freed the city from the spending caps in the Taxpayer’s Bill of Rights to restore cut services, the city can tap into unused mill levy capacity without asking voters to increase taxes.

Hancock’s office has said the maximum increase under consideration is 1 mill.

Though developers would pay the upfront impact fees, Kniech said the property tax increase is important because it would spread the burden for paying for the affordable housing initiative more widely. “We think it’s important that every resident of Denver is participating,” she said.