| Chicago Market Expansion Project | Natural Gas Pipeline Company of America LLC | IL | In service 2016 | |
| Chilton Loop Pipeline Project | Williams | AL | | |
| Chinook Export | | MT | In service 2001 | |
| Chippewa Compressor Station | Dominion Energy Ohio | OH | | |
| Chippewa Export Permit | Empire Pipeline, Inc. | NY | In service 2010 | |
| Chisholm III | Enlink Midstream | OK | Started 2017 | |
| Cimarron River Pipeline PF17-7 | Cimarron River Pipeline, LLC | | | |
| Cincinnati Gas & Electric OPSB case 02-1350-GA-BTA | Cincinnati Gas & Electric Co | OH | | |
| Cincinnati Gas & Electric OPSB case 02-3256-GA-BTA | Cincinnati Gas & Electric Co | OH | | |
| Cincinnati Gas & Electric OPSB case 06-0444-GA-BTX | Cincinnati Gas & Electric Co | OH | | |
| Cincinnati Gas & Electric OPSB case 95-0094-GA-BTX | Cincinnati Gas & Electric Co | OH | | |
| Cincinnati Gas & Electric Rialto OPSB case 98-0285-GA-BLN | Cincinnati Gas & Electric Co | OH | | |
| Cincinnati Gas & Electric Rialto OPSB case 98-0946-GA-BLN | Cincinnati Gas & Electric Co | OH | | |
| City of Duluth Public Works & Utilities CP03-18 | City of Duluth Public Works & Utilities | MN, WI | | |
| City of Jackson Pipeline Replacement Project | Gulf South Pipeline Company, LLC | MS | 2011–2012 | |
| Clarence Compressor | Gulf South Pipeline Company, LLC | LA | 2011 | |
| Clarington Connector | EQT Corp. | OH, PA | | |
| Clarington Project | Dominion Transmission, Inc. | OH, WV | In service 2016 | |
| Clarion Compressor Station | Northern Natural Gas Company | IA | | |
| Clarksville Gas and Water - Natural Gas Interconnect Pipeline Project | City of Clarksville, Tennessee | KY, TN | | |
| Clarksville Lateral Project | Enable Gas Transmission, LLC | | | |
| Claude Unit 1 Replacement Compression Station Project | Northern Natural Gas Company | | | |
| Clay Basin Delivery Project | Dominion Energy Questar Pipeline, LLC | UT | | |
| Cleco Corporate Holdings coastal use permit P20200549 pipeline | Cleco Corporate Holdings, LLC | LA | | |
| Cleco Power coastal use permit P20160319 pipeline | Cleco Power LLC | LA | | |
| Cleco Power coastal use permit P20191028 pipeline | Cleco Power LLC | LA | | |
| Cleco coastal use permit P19960298 pipeline | Cleco Corporation | LA | | |
| Clendenin Compressor Station Replacement | Columbia Gas Transmission, LLC | WV | | |
| Clendenin Compressor Station Uprate | Columbia Gas Transmission, LLC | WV | Started 2014 | |
| Cleveland Compressor Station Replacement | Columbia Gas Transmission, LLC | WV | | |