| Columbia River | OR | Lake/Reservoir/Pond | Not Supporting | 5 | 4,459 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 202 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 76 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 203 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 168 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 177 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 5 | 69 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 192 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 163 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 95 |
| Columbia River (Franklin D. Roosevelt Lake) | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 42 |
| Columbus City Park Pond | NE | Lake | Not Supporting | 1 | 4.00 |
| Columbus Mill Pond | WI | Impoundment | Not Supporting | 1 | 18 |
| Columbus Park Lag. | IL | Lake, Freshwater | Not Supporting | 1 | 5.80 |
| Columbus Park Lake | IL | Lake, Freshwater | Not Supporting | 2 | 7.00 |
| Colwich City Lake | KS | Lake | Not Supporting | 2 | 10 |
| Comanche Lake | OK | Lake, Freshwater | Fully Supporting | 0 | 184 |
| Combie, Lake | CA | Lake/Reservoir/Pond | Not Supporting | 1 | 269 |
| Combs Lake | KY | Lake/Reservoir/Pond | Fully Supporting | 0 | 33 |
| Comerford | VT | Lake, Freshwater | Not Supporting | 1 | 777 |
| Comfort | MN | Lake, Freshwater | Not Supporting | 2 | 212 |
| Comfort | MN | Lake, Freshwater | Not Supporting | 1 | 43 |
| Comins Reservoir | NV | Reservoir | Not Supporting | 1 | 136 |
| Commerce Lake Oakley Park Beach | MI | Inland Lake Shoreline | Not Supporting | 1 | Filed in miles |
| Commerce Park Wildlife Pond Dam | NH | Impoundment | Not Supporting | 1 | 7.60 |
| Commston Lake | FL | Lake, Freshwater | Not Supporting | 1 | 14 |
| Como | MN | Lake, Freshwater | Not Supporting | 3 | 68 |
| Como Lake (Bloomer Mill Pond) | WI | Impoundment | Not Supporting | 1 | 98 |
| Compass Lake | FL | Lake, Freshwater | Not Supporting | 1 | 582 |
| Compensating Res. (L. McDonough) (Barkhamsted/New Hartford) | CT | Lake, Freshwater | Not Supporting | 1 | 386 |
| Comus Lake | WI | Reservoir | Not Supporting | 1 | 131 |
| Conc/Beaver Dam | NH | Impoundment | Not Supporting | 1 | 0.15 |
| Concannon SFL | KS | Lake | Not Supporting | 3 | 70 |
| Conchas Reservoir | NM | Reservoir | Not Supporting | 2 | 3,411 |
| Conconully (Salmon) Lake | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 292 |
| Concord Pond | DE | Lake/Reservoir/Pond | Not Supporting | 1 | 78 |
| Cone Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 9.03 |
| Conecuh River (Gantt Lake) | AL | Reservoir | Not Supporting | 2 | 1,817 |
| Conecuh River (Point A Lake) | AL | Reservoir | Not Supporting | 2 | 611 |
| Conemaugh River Lake-05010007000003 | PA | Lake/Reservoir/Pond | Not Supporting | 2 | 800 |
| Conestoga Lake | NE | Lake | Not Supporting | 5 | 189 |
| Conesus Lake | NY | Lake/Reservoir/Pond | Not Supporting | 2 | 3,208 |
| Congamond Lakes | MA | Lake, Freshwater | Not Supporting | 5 | 279 |
| Congamond Lakes | MA | Lake, Freshwater | Not Supporting | 4 | 144 |
| Congamond Lakes | MA | Lake, Freshwater | Not Supporting | 3 | 46 |
| Conneaut Lake-05010004001653 | PA | Lake/Reservoir/Pond | Not Supporting | 3 | 951 |
| Connecticut River - Bellows Falls | NH | Impoundment | Not Supporting | 2 | 1,720 |
| Connecticut River - Canaan Hydro | NH | Impoundment | Not Supporting | 2 | 20 |
| Connecticut River - Comerford Storage Dam | NH | Impoundment | Not Supporting | 1 | 1,093 |
| Connecticut River - Dodge Falls | NH | Impoundment | Not Supporting | 1 | 290 |