| Siwash Slough | Skagit, WA | 29.9 miles | SE |
| Cap Sante Waterway | Skagit, WA | 31.8 miles | SE |
| Blind Slough | Skagit, WA | 37.4 miles | SE |
| Telegraph Slough | Skagit, WA | 37.4 miles | SE |
| Higgins Slough | Skagit, WA | 38.1 miles | SE |
| Sullivan Slough | Skagit, WA | 41.7 miles | SE |
| Douglas Slough | Snohomish, WA | 50.8 miles | SE |
| Davis Slough | Island, WA | 52.2 miles | SE |
| Irvine Slough | Snohomish, WA | 52.9 miles | SE |
| Barnaby Slough | Skagit, WA | 63.9 miles | SE |
| Deadman Slough | Snohomish, WA | 72.3 miles | SE |
| Deadwater Slough | Snohomish, WA | 73.2 miles | SE |
| Hanson Slough | Snohomish, WA | 79.2 miles | SE |
| Batt Slough | Snohomish, WA | 79.7 miles | SE |
| Mercer Slough | King, WA | 99 miles | SE |
| Green Slough | King, WA | 99.9 miles | SE |
| Horseshoe Slough | King, WA | 100.1 miles | SE |
| Stickney Slough | King, WA | 101.1 miles | SE |
| Rutherford Slough | King, WA | 103.5 miles | SE |
| Meadowbrook Slough | King, WA | 108.7 miles | SE |
|