ORONO, Maine — An estimated 1,687 students are expected to graduate from Maine’s largest university during May 9 commencement ceremonies.

The flagship campus of the University of Maine System is celebrating its 150th birthday this year, but this will be its 213th commencement, because in the past the university distributed degrees and held graduations more than once per year, according to university spokeswoman Margaret Nagle.

The commencement will be split into two sessions, one at 10 a.m. and the other at 2:30 p.m., held inside the Harold Alfond Sports Arena.

In the morning, students from the College of Education and Human Development, the College of Liberal Arts and Sciences, the Division of Lifelong Learning and the Maine Business School will walk on stage to receive their degrees. They’ll be followed in the afternoon by students in the College of Engineering and the College of Natural Sciences, Forestry and Agriculture.

The university cautions that traffic through Orono is likely to be heavy on commencement day, and suggests that families and friends attending the ceremony plan on arriving early. Doors open at 8 a.m. for the morning ceremony and at 1 p.m. for the afternoon.

UMaine urges attendees to park in the Collins Center for the Arts parking lot, where shuttle busses will transport people to and from the ceremony on the other end of campus.

This year’s valedictorian is Gwendolyn Beacham of Farmington, an honors student and biochemistry major. Katelyn Massey of Waterville will be honored as salutatorian. Massey is psychology major with a concentration in development and a minor in communication sciences and disorders, as well as a member of the women’s ice hockey team.

Honorary doctorate degrees will be awarded to Dana Connors of Gray, an alumni and president of the Maine State Chamber of Commerce; Dennis Rezendes of Boulder, Colorado, who graduated from UMaine in 1957 and went on to help spearhead the hospice services movement in the United States; and Peter McPherson, president of the Association of Public and Land-grant Universities, a national research, policy and advocacy organization.

McPherson also will deliver commencement keynote addresses at both ceremonies at Maine’s land-grant institution.

Both ceremonies are ticketed events, but university will live stream the commencements for those who can’t attend at umaine.edu/commencement/live-feed.

Follow Nick McCrea on Twitter at @nmccrea213.