HARRISBURG - Estelle B. Richman, who has headed the state Department of Public Welfare for the last seven years, is stepping down to take a top position in the U.S. Department of Housing and Urban Development.

She will become the chief operating officer on Jan. 4, Gov. Rendell announced today.

Rendell called Richman "a beacon of hope for so many people" and the "most effective" welfare secretary in the history of Pennsylvania.

"For me, this is a very sad moment," the governor said at a news conference. "My sadness is only tempered by the fact that Estelle is going to go to work for an equally important government mission.

". . . Our loss is Washington's gain."

In announcing her decision, Richman, 66, recalled how as a African American girl growing up Virginia she attended segregated schools until high school.

"I never thought, and my parents and my grandparents never believed, that there would be a black president," she said. "To have the honor of working in the Obama administration is something that I felt at this point in my life that I wanted to do and that I didn't want to turn down."

Also today, Rendell that he has tapped Harriet Dichter, the state's deputy secretary for child development and early learning, to replace Richman at welfare, one of the state's largest agencies with 19,000 employees and an annual budget topping $9 billion.

Richman was Philadelphia's managing director for Mayor John Street before Rendell picked her as a member of his original cabinet in 2003. She was the city's health commissioner when he was mayor.

Richman's departure means that of the 17 original members of Rendell's cabinet, only two remain - Corrections Secretary Jeffery Beard and Transportation Secretary Allen Biehler.

Contact staff writer Mario F. Cattabiani at 717-787-5990 or mcattabiani@phillynews.com.