The Rev. David M. O'Connell, president of the Catholic University of America, has been named the next bishop of the Diocese of Trenton.

O'Connell, 55, who was born in Philadelphia and grew up in Langhorne, will be installed as coadjutor, or successor, bishop July 30 at St. Mary of the Assumption Cathedral in Trenton.

He will succeed Bishop John M. Smith, who turns 75 on June 23, whenever Pope Benedict XVI accepts Smith's resignation. Standard retirement age for Catholic bishops is 75, but no date has been set for the succession.

The diocese comprises Burlington, Monmouth, Ocean, and Mercer Counties, and has 111 parishes and 830,000 members.

In remarks Friday, O'Connell described the diocese, where he attended high school in Princeton, as his "second home."

"I can't count how many times I passed that bridge with the words written Trenton Makes, the World Takes," O'Connell said. He said he hoped "to serve and not be served," and chose that phrase as his episcopal motto.

Smith, who has led the diocese since 1997, predicted Friday that the diocese would be in good hands with O'Connell, a Vincentian priest credited with expanding and improving Catholic University during his nearly 12-year tenure as president.

Under O'Connell's leadership, the university in Washington increased its student population by 23 percent, expanded its campus 34 percent, to 193 acres, added and improved buildings, and raised $180 million, according to the Washington Post.

In April 2008, O'Connell hosted a visit from Pope Benedict to the campus, which is also home to the John Paul II Center, an interactive museum of Catholicism and a center for advanced Catholic studies.

Contact staff writer David O'Reilly at 215-854-5723 or doreilly@phillynews.com.