- Headquarters/York Office
- The Russell E. Horn Building
- Contact: Iris Fultz - Corporate Secretary
- 445 West Philadelphia Street
- York, PA 17401-3383
- (717) 852-1400
- Pittsburgh Office
- Liberty Technology Center
- Contact: Jay A. Sabo, PE, Vice President – Northern Transportation Operations
- 2200 Liberty Avenue
- Suite 300
- Pittsburgh, PA 15222-4502
- (412) 261-5059
- State College Office
- Contact: Scott E. Russell, PE, Senior Vice President - Water Resources
- 2009 North Atherton Street
- Suite 200
- State College, PA 16803
- (814) 237-7111