The former commissioner of the New York City Department of Environmental Protection (DEP) has been hired to run the General Contractors Association (GCA), raising concerns from local officials over the possibility of a conflict of interest.

Christopher Ward presided over the DEP when it finally succeeded in securing approval for construction of the Croton water filtration plant in Van Cortlandt Park. The GCA, a lobbying organization representing construction contractors, was a major supporter of the project.

“No one knows at what point in time Commissioner Ward knew that he would become the general manager of the GCA,” said Assemblyman Jeffrey Dinowitz in a statement, “but the appearance couldn’t be worse. At best, this shows very poor judgment and a conflict of interest.”

Councilman Oliver Koppell echoed that sentiment. “I think it’s very regrettable and casts a lot of doubt on his objectivity when he pushed so hard to get a filtration plant in Van Cortlandt Park,” he said. “It doesn’t smell good.”

Restrictions outlined by the New York City Conflicts of Interest Board state that an individual may not appear before his or her old city agency on business for one year; that an individual may never work on something that he or she was directly involved with while employed by the city; and that an individual cannot divulge confidential city information to benefit himself or his employer.

Mark Davies, executive director of the Conflicts of Interest Board, said high-level officials often consult with his office — and can seek waivers from conflict-of-interest culpability — before changing careers, but that Ward had not.

Ward, who left the DEP in late 2004 to run American Stevedoring in Brooklyn, did not return calls seeking comment.