15 bridges with vertical clearance data on SR-20 in Washington. Lowest: 155.8ft.
| Clearance | Carries | Crosses | Location | Built | Map |
|---|---|---|---|---|---|
| 155.8ft | Sr 20 | Ship Hbr/Guemes Channel | 7.8N On Sr20 Spur | 1959 | Map |
| 160.1ft | Sr 20 Extension | Keystone Harbor | 3.4 W Jct Sr 525 | 1979 | Map |
| 160.1ft | Sr 20 Extension | Friday Hbr-San Juan Chan | Ne End San Juan Isl | 1968 | Map |
| 160.1ft | Sr 20 | Ship Hbr/Guemes Channel | 7.8N On Sr20 Spur | 1959 | Map |
| 160.1ft | Sr 20 | Ship Hbr/Guemes Channel | 7.8N On Sr20 Spur | 1971 | Map |
| 160.1ft | Extension Of Sr 20 | Upright Channel | N End Lopez Island | 1981 | Map |
| 160.1ft | Sr 20 | Puget Snd @ Pt Townsend | 12.9 E Jct Us 101 | 1955 | Map |
| 160.1ft | Sr 20 | Harney Channel | On Orcas Island | 1979 | Map |
| 160.1ft | Sr 20 | Ship Hbr/Guemes Channel | 7.8N On Sr20 Spur | 1971 | Map |
| 160.1ft | Ferry Traffic | Blind Bay | Blind Bay-San Juan | 2004 | Map |
| 160.1ft | Sr 20 Extension | Friday Hbr-San Juan Chan | Ne End San Juan Isl | 2005 | Map |
| 165.0ft | Sr 20 | Methow River | 30.8 E Chelan Co | 1929 | Map |
| 240.8ft | Sr 20 | Railroad | 0.3 E Jct Sr 215 | 1959 | Map |
| 450.1ft | Sr 20 | Swinomish Chan | 9.3 E Island Co | 1972 | Map |
| 450.1ft | Sr 20 | Swinomish Channel | 9.3 E Island Co | 1981 | Map |