| Connecticut River - Dodge Falls (Tailrace of Mcindoes Dam) | NH | Impoundment | Not Supporting | 1 | 10 |
| Connecticut River - Gilman Dam Pond | NH | Impoundment | Not Supporting | 2 | 3,800 |
| Connecticut River - Mcindoes Reservoir | NH | Impoundment | Not Supporting | 1 | 545 |
| Connecticut River - Vernon Dam | NH | Impoundment | Not Supporting | 1 | 2,000 |
| Conner Lake | VA | Reservoir | Not Supporting | 1 | 102 |
| Conner Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 85 |
| Conners Lake | WA | Lake/Reservoir/Pond | Not Supporting | 1 | 40 |
| Connors Lake | WI | Lake, Freshwater | Fully Supporting | 0 | 410 |
| Conowingo Reservoir | MD | Impoundment | Not Supporting | 3 | 3,070 |
| Conservation Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 11 |
| Conservation Pond Dam | NH | Impoundment | Not Supporting | 1 | 0.33 |
| Constable Pond | NY | Lake/Reservoir/Pond | Not Supporting | 1 | 38 |
| Constance | MN | Lake, Freshwater | Not Supporting | 1 | 166 |
| Constance Lake | NH | Lake/Reservoir/Pond | Not Supporting | 3 | 8.02 |
| Contention Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 94 |
| Continental Reservoir. | CO | Lake/Reservoir/Pond | Not Supporting | 1 | 374 |
| Contoocook Lake | NH | Impoundment | Not Supporting | 1 | 116 |
| Contoocook Lake | NH | Lake/Reservoir/Pond | Not Supporting | 3 | 227 |
| Contoocook Lake - Town Beach | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 1.28 |
| Contoocook River | NH | Impoundment | Not Supporting | 4 | 0.50 |
| Contoocook River - Camp Spaulding Beach | NH | Impoundment | Not Supporting | 1 | 1.38 |
| Contoocook River - Contoocook Village Dam | NH | Impoundment | Not Supporting | 1 | 110 |
| Contoocook River - Hoague-Sprague Dam | NH | Impoundment | Not Supporting | 1 | 2.00 |
| Contoocook River - Hopkinton Flood Control Dam | NH | Impoundment | Not Supporting | 1 | 220 |
| Contoocook River - Hosiery Mill Dam | NH | Impoundment | Not Supporting | 1 | 8.00 |
| Contoocook River - Monadnock Power Dam Pond | NH | Impoundment | Not Supporting | 1 | 40 |
| Contoocook River - Noone Mill Pond | NH | Impoundment | Not Supporting | 2 | 18 |
| Contoocook River - North Village Dam | NH | Impoundment | Not Supporting | 1 | 17 |
| Contoocook River - Paper Mill Dam | NH | Impoundment | Not Supporting | 1 | 5.00 |
| Contoocook River - Penacook Lower Falls | NH | Impoundment | Not Supporting | 2 | 8.50 |
| Contoocook River - Penacook Upper Falls Dam | NH | Impoundment | Not Supporting | 2 | 11 |
| Contoocook River - Pierce Power Dam | NH | Impoundment | Not Supporting | 2 | 3.50 |
| Contoocook River - Transcript Printing Co Dam | NH | Impoundment | Not Supporting | 2 | 2.50 |
| Contoocook River - York Dam Pond | NH | Impoundment | Not Supporting | 1 | 250 |
| Contoocook River Dam | NH | Impoundment | Not Supporting | 4 | 5.00 |
| Contra Loma Reservoir | CA | Lake/Reservoir/Pond | Not Supporting | 1 | 66 |
| Conway Lake | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 1,313 |
| Conway Lake - Town Beach | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 0.51 |
| Cook | MN | Lake, Freshwater | Not Supporting | 1 | 89 |
| Cook | VT | Lake, Freshwater | Fully Supporting | 0 | 3.00 |
| Cook Lake | IN | Lake, Freshwater | Not Supporting | 1 | 93 |
| Cook Lake Taylor's Beach | MI | Inland Lake Shoreline | Not Supporting | 1 | Filed in miles |
| Cooks (Shrwby) | VT | Lake, Freshwater | Fully Supporting | 0 | 12 |
| Cooks Pond | MA | Lake, Freshwater | Not Supporting | 4 | 21 |
| Cooks Pond | NH | Lake/Reservoir/Pond | Not Supporting | 1 | 33 |
| Cooks Pond | NH | Lake/Reservoir/Pond | Not Supporting | 2 | 246 |
| Cooks Pond-02050106002544 | PA | Lake/Reservoir/Pond | Fully Supporting | 0 | 33 |
| Cookstove Lake | SD | Lake/Reservoir/Pond | Not Supporting | 1 | 2.42 |
| Cool Run | NJ | Lake | Fully Supporting | 0 | 37 |
| Cooley Lake | WI | Lake, Freshwater | Not Supporting | 1 | 62 |