An apartment project under construction in the District in March. (Michael S. Williamson/The Washington Post)

Washington-area elected officials voted Wednesday to push their local governments to address the region’s affordable-housing shortage by setting individual targets to increase production of low- and medium-cost housing by 2030.

The Metropolitan Washington Council of Governments (COG) said the region needs to add 320,000 housing units between 2020 and 2030 — 75,000 more units than forecast.

Of those, at least three-quarters should be affordable to low- and middle-income households, according to a resolution approved unanimously by the COG board, which means they should cost $2,500 a month or less.

In addition, at least three-quarters should be in employment centers or near transit, to reduce commuting times and curb the region’s chronic traffic congestion, COG said.

The COG proposal, in the works for more than a year, sets what many officials and experts view as a necessary and worthy goal for the region. The alternative, they warned, is a housing crisis similar to those seen on the West Coast.

“You can’t afford to live in San Francisco — the workforce [there] is being displaced,” said COG Vice Chair Derrick Leon Davis (D), who headed the panel’s Housing Strategy Group and is a Prince George’s County Council member representing District 6.

“We don’t want to be that region,” Davis said.

But COG, the region’s planning body, has no power to enforce its recommendations, and it set no deadline for jurisdictions to commit to housing targets.

Even though the board’s membership is composed of elected leaders from the 24 county and municipal governments in the region — comprising the District, Northern Virginia and Maryland suburbs — the individual jurisdictions are free to ignore the call if they choose.

That is significant because it will be costly and politically difficult for individual jurisdictions to make the far-reaching changes necessary to overcome the affordable-housing shortage.

Reaching the target would require increasing public subsidies, such as for rental vouchers and low-cost loans. That would mean raising taxes or redirecting funds from other priorities such as schools and transportation.

It also would require relaxing zoning and regulatory restrictions to allow for increased density, such as more multifamily apartment buildings in neighborhoods dominated by single-family homes. Such proposals frequently face opposition from residents worried about more traffic, crowded schools and changes in the character of their communities.

This is the tackle of the generation to come,” Davis said. “We do know that housing affordability in this region is going to be a very, very difficult task.”

A COG staff report acknowledged that the jurisdictions “face a variety of challenges — from community dynamics and market forces, to competing funding priorities and reduced federal resources.”

It called for “a range of tools and innovative policies to meet these targets, including strategic partnerships with the business, nonprofit and philanthropic sectors.”

The COG action comes a week after the release of an Urban Institute report that made many of the same recommendations. The COG staff report cited that study in saying that more than a half-million of the region’s households are “housing cost-burdened,” which means they spend more than 30 percent of their income on housing.

Residents in middle- and low-wage occupations who are most affected include service workers, nursing attendants, paramedics, security guards, firefighters and graphic designers.

“The region’s current unmet housing needs undercut its appeal to new companies and talent, strain the transportation system and impact the environment and quality of life for residents,” the report said. “The solution is for housing to be preserved and created at a higher rate than has been achieved in the recent past.”

COG also estimated that more than 325,000 people commute daily into metropolitan Washington from outside the region because they cannot afford to live closer to their jobs.

“For some, this means not only long commutes to work, but also difficult choices between paying rent or affording other basic necessities such as food or medicine,” the report said.

In urging individual jurisdictions to commit to increase the production of affordable housing, COG did not specify what targets each county or municipality should set. But it suggested that they could divide up the responsibility according to how much their population was expected to grow.

The only jurisdiction that has set a numerical target for increased affordable-housing production is the District. Mayor Muriel E. Bowser (D) has pledged to add 36,000 units by 2025, of which one-third will be affordable housing.

Leaders of Fairfax and Montgomery counties, the region’s two most populous jurisdictions, expressed optimism after the vote that their governments would address housing — but they declined to predict when they would set specific targets.

Montgomery County Council President Nancy Navarro (D-District 4) said her goal was for the council to approve a resolution on housing by November. Fairfax Board of Supervisors Chair Sharon Bulova (D-At Large) said a new board to be elected in November appears likely to favor doing more for affordable housing.

The COG report noted that Montgomery and Arlington counties, along with the District, are allowing residents to build accessory dwelling units to increase density. Fairfax, Prince George’s and Arlington have developed comprehensive housing strategies.

COG leaders also said they were encouraged that regional business and nonprofit leaders were showing more interest in taking action to build more affordable housing.

But officials acknowledged that public resistance can be strong.

“This climate of fear is out there,” Rockville Mayor Bridget Donnell Newton said. “When people hear ‘more housing,’ they are immediately panicked about the roads and schools.”

COG Chairman Robert C. White Jr. (D), an at-large member of the D.C. Council, said the setting of targets was only a first step.

“What none of us wants is to spend all this time and effort with the region, with governments, with nonprofits, with the private sector, just to do a report that doesn’t get acted upon,” White said. “The most important part of this is the action that follows. So we will be pushing each other.”