Even by the year 2030 the population of Cambridge won’t quite match the high of 1950, according to a report released today by the Metropolitan Area Planning Council.

The regional planning agency released projected population figures for Boston and its surrounding area – 101 cities and towns – as part of a look at housing needs through 2040 and found that the area could age along with retiring baby boomers and stagnate, with jobs in the region growing by less than 1 percent, or take steps to attract younger residents in greater numbers. In that “Stronger Region” scenario, the labor force grows by 7 percent but there would need to be 435,000 units of housing built to accommodate the growth, mainly in cities and with few being single-family homes.

A report by the Metropolitan Area Planning Council sees a need for 435,000 units of housing to be built in and around Boston by 2040.

“This new report confirms the need for significant new multi-family housing if we want to attract young people and families and to grow our population,” Housing and Economic Development Secretary Greg Bialecki said.

Yet despite a building boom and allure to younger residents that continued without pause through the recent recession, projections for Cambridge don’t get it back to the 120,740 people recorded in the 1950 census.

The city’s population grew to 106,471 as of July 1, 2012, according to the city’s Community Development Department – a 5 percent increase in a dozen years. But council projections in the more aggressive scenario based on current patterns of births, deaths and migration (and some assumptions about how those trends might change) put the city’s population at 112,359 by the end of this decade and at 118,625 by 2030.

The more aggressive scenario counts on the region attracting and retaining even more people, especially young adults, than it does today, with people born after 1980 craving dense city living instead of the suburbs and more seniors giving up empty-nest single-family homes in favor of  apartments or condominiums. It’s gospel in Massachusetts; in 2012, the Executive Office of Housing and Economic Development adopted it as the basis for the goal of building 10,000 multifamily units per year. State spending toward that goal in Cambridge pales beside what the private sector wants to do here, though.

Thousands on the way

Just four projects coming along in Alewife will bring some 1,298 units to the area, or roughly 1,903 new residents, while North Cambridge development watchdogs have identified some 700 more units good for another 1,000 or so people. When the so-called K2C2 studies were wrapped up in December by city planners, a final report on Kendall Square said “another 2,000 to 3,500 units could be expected to be built in Kendall Square or within walking distance” over the next several years, including Central Square, on Main Street and in NorthPoint and East Cambridge, which could mean another 5,131 residents based on the variety of units being built in the city by developers Cabot, Cabot & Forbes; Criterion Development; Cube3; Hines; and The McKinnon Co.

None of this takes into account the addition of “micro-units” to housing stock for younger workers and downsizing seniors who can get by with less square footage in their living space. The Central Square final report from the K2C2 process calls for the city to “remove zoning and permitting barriers to allow ‘micro-unit’ development … where appropriate.”

To give some sense of Cambridge’s effectiveness in drawing residents: The city’s population grew 3.8 percent between 2000 and 2010, despite the recession clouding the final three years of the decade. The populations in neighboring Somerville and Watertown fell 2.2 percent and 3.3 percent in the same decade, respectively. Populations grew in neighboring Arlington and Belmont, but by 1.1 percent and 2.2 percent respectively. Nearby Medford saw faint population growth of 0.7 percent.

A Cambridge population problem

If anything, Cambridge has been an even bigger draw in terms of commercial development, with city councillors complaining increasingly that the success of the city and its Kendall Square as a business and innovation center is squeezing out both the startup firms that give the area vitality and existing residents, who have to leave when landlords raise rents to take advantage of better-paid engineers and executives.

As a result, the city is commissioning a “nexus study” paid for by the Affordable Housing Trust on how commercial real estate affects housing.

“While prior nexus studies have examined the impact on housing affordability for low- and moderate-income residents, in this study we will also ask that housing affordability for middle-income households be considered,” said Brian Murphy, assistant city manager and head of Community Development, in a memo announcing the study.

When building needs go beyond what zoning allows, a company goes to the city for a special permit and pays into an “incentive zoning” fund that adds to the city’s affordable-housing stock.

This study to find how the permit and payment formula should be overhauled would likely be similar to the first, in 1988, and an update in 2002 that surveyed office workers and found how many moved to Cambridge for a job, Murphy told councillors Monday. The previous study found 183 workers moving here annually, of whom three-quarters rented rather than bought.

“I’m assuming the ballpark for that is an increase by an order of magnitude?” said councillor Nadeem Mazen, referring to the 183 workers.

Murphy agreed there had been a boom in office and lab space that would result in far more workers moving to the city, but said he suspected square footage needs had changed as well.

Still, only two projects paid incentive zoning money last year of just over $500,000, and before that the last project to pay was in 2009, Murphy said. There were four coming along, but also commercial projects underway “that have not required a set of payments because the particular permits they required aren’t subject to the ordinance. This may well be another recommended change,” he said, naming developments by the biotech firm Novartis, developer Alexandria Real Estate Equities and by the Massachusetts Institute of Technology at 610 Main St. as the kind of projects the city would look at for contributions.

“I’m very pleased to see this nexus study going forward. It is my understanding this study is essential to the conversation we’re going to have … and my hope that we’re going to see a lot more projects where the incentive zoning is covered and we’ll see a lot more revenue,” Mayor David Maher said. “While we have seen rapid growth in this community and we can celebrate the rapid growth, there has been a negative impact on certain segments in the community, and that’s what we’re all interested in.”