State and local dignitaries cut the ribbon Tuesday on a $46.4 million improvement project along Windy Hill Road in the Cumberland area of Cobb County.

Highlighted by a new diverging-diamond interchange at Windy Hill and Interstate 75 north of the new SunTrust Park, the work along Windy Hill stretches from Powers Ferry Road west to Cobb Parkway.

“A 30-year plan is beginning to come to fruition,” Lt. Gov. Casey Cagle said during a ceremony held along Windy Hill Road just east of the new interchange.

The…