 In 1989, the Conservancy assisted the City to rezone the residential neighborhoods north of Hadley Street to protect this vital area from rampant, uncontrolled apartment construction.The Conservancy spearheaded the preservation of the historic Whittier Depot and the McGee House.Though primarily a historic preservation organization, the Conservancy is also interested in open space preservation, and is involved in the continuing movement to preserve the Whittier Hills as part of the Puente-Chino Hills Wildlife Corridor 

On May 23, 2007, the Conservancy filed suit against the City of Whittier.