Although 2030 may seem far in the future, population projections extending out to that year are out, and growth projections are mixed.
According to a report by the University of Massachusetts Donahue Institute, the populations of Groton, Harvard and Shirley are expected to grow between now and 2030, while Ayer, Pepperell and Townsend are projected to shrink over the same period.
Shirley is expected to increase the most, from 7,211 in 2010 to 8,829 in 2030, a 22 percent increase. Townsend is projected to shrink by 18.8 percent, from 8,926 to 7,246.
Susan Strate, the population estimates program manager at the Donahue Institute, said that while projections for each town take into account the trends of their region as a whole, the report also preserves the individual characteristics of the towns, and are largely based on the town's population changes over the previous 10 years.
The study organized the state into regions, with Ayer, Harvard, Shirley and Townsend categorized as Metro West, and Groton and Pepperell as part of the Northeast region. The Metro West region is expected to grow by 6 percent by 2030, while the Northeast is expected to grow 3.5 percent.
Regional planning efforts and development within towns is not taken into account when calculating the projections, Strate said.
The towns with declines could be affected by an exiting of young people from the region, Strate said, as small towns offer fewer educational and job opportunities for young adults.
"It's probably to move on to college and new job opportunities. Those towns are more of residential, suburban.
However, this could turn around eventually.
"Your regions will make it through that because as the Millennials, who are mostly in college and their 20s now, start families, we can expect them to move back into these regions," she said.
The major outlier in the region is Ayer, Strate said, which has shown sharp changes in population growth and reduction over the years, while other towns have remained on fairly consistent trajectories.
Unique to Ayer is the former Fort Devens, which was decommissioned in the 1990s. Departure of that full-time military population had a significant impact on the town's population.
But at the Montachusett Regional Planning Commission, the most recent population predictions, from 2012, showed steady growth across the region.
Although MRPC does not cover Pepperell, the towns of Ayer, Groton, Harvard, Shirley and Townsend are all expected to grow by the commission's predictions.
Glenn Eaton, MRPC executive director, said that overall, the proximity to major job centers will keep the population on track.
"One job generator for the region is obviously the large job centers of Lowell, Worcester, Boston, Fitchburg and Leominster and Nashua that surround those rural towns. Within the towns you have some companies like Sterilite in Townsend, but you don't have a lot of them. It's a pretty rural area, more trees than businesses. Groton is not a Fitchburg or a Leominster but it is impacted by those other metros," Eaton said.
However, Eaton said that certain pockets of the population, such as young adults, could see declines as predicted by the Donahue Institute, although they will not be drastic enough to affect the population as a whole.
"The people moving there might be older, more stable, and have more income or wealth and be able to afford pricier real estate in the Harvards and Grotons," Eaton said.
Across the Montachusett region, which includes Fitchburg and Leominster and extends as far west as Athol, Eaton said overall population growth has been steady, at about a half a percent to 1 percent per year.
"We didn't project a lot of declines, if any. It was a slow, stable growth. Not a large growth, but certainly no declines," Eaton said.
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