The Greater Beverly YMCA is set to celebrate the start of construction of a $7.5 million expansion of its Sterling YMCA campus on Monday, April 24. Mayor Michael P. Cahill and other city leaders are joining Y officials at a 10:30 a.m. groundbreaking at the Essex Street site. The Sterling campus includes a main building with a fitness center, a pool, a gymnastics center, and a gymnasium; and a separate teen center housing two basketball courts and an early learning center. Part of the project involves a two-floor expansion of the main building that will increase space for the fitness center, group exercise studios, the family locker room, and a baby-sitting area. A community gathering room and an elevator will be added. The expanded area will be named the Ralph E. Bates Healthy Living Center, after the donor who provided $1 million for the expansion. The project also involves construction of a third campus building that will house space for infant and toddler care, and after-school and summer programming. The Y has raised $4.1 million for the project, and is continuing to seek funds to cover the remaining cost.John Laidler can be reached at firstname.lastname@example.org.