MANKATO — Changes in student numbers in the Mankato school district have prompted a proposal for changes in school boundaries now, and likely the future construction of a school on the east side of town and an addition to one on the west side.

Mankato Area Public Schools Supt. Sheri Allen said families of students at Hoover and Washington elementaries already have been notified that portions of the respective schools’ attendance areas, pending School Board approval, will be broken off and added to other schools. In Hoover’s case, some of its students would go to Monroe. In Washington’s case, they’d go to Rosa Parks. (See accompanying map.)

The board will vote Monday on that matter.

They’ll also vote on whether to begin the process of a bricks-and-mortar project that, again, was prompted by growth on the east side of town and the need for more space on the west side.

Allen said she’ll recommend to the board the construction of a sixth- through eighth-grade building on the east side of town as well as expansion of Dakota Meadows Middle School to include a wing for sixth-graders.

The Garfield Elementary building — now used for west-side sixth-graders — then could be used to house programs for which the school district now leases space. One of the costliest leases the district has is for Bridges Community School. The district pays $116,600 to lease St. Joseph the Worker Church for that school.

(It pays another $147,020 to lease space in the South Central Services  Cooperative building for its Student Support Services offices. Both Bridges and student support, in theory, could be housed in Garfield.)

All the moves, including boundary changes and decisions to build, are based on enrollment projections.

By the 2016-2017 school year, elementary school enrollments are expected to exceed Mankato Area Public Schools’ current capacity by 176 students. East secondary enrollment — including both East Junior and Senior high schools — are expected to exceed capacity by 188 students.

East/West boundaries will not be affected by the proposed changes.

If approved, the boundaries won’t officially go into effect until fall of 2013. But affected families can make the switch a year early. Allen said they’d already heard from a family with a child starting kindergarten next year. They’ve decided to switch now instead of attending Hoover for one year and then switching to Monroe the following year.

As for the building projects, Allen said she doesn’t have a rough estimate yet of what it would cost to build a new middle school and add on to Dakota Meadows. By fall, she said, after school officials have had time to do research and hear back from architects, they’ll have a rough idea of what it would cost.

After that, the issue must go before the voters in a referendum.

Their research, however, shows there is some support in the community for such a project.

In a recent survey, 44 percent supported spending for a new middle school. About 32 percent supported funding a new elementary school. Just 20 percent supported replacing West High School’s pool and 18 percent supported expanding the school’s cafeteria.