Southwest Pass survey data is referenced to Louisiana South State Plane Coordinates North American Data 1983 with sounding reference below Mean Lower Low Water in U.S. Survey Feet unless otherwise noted on the plan sheet.
SPECIAL NOTICE: Bypass channel for the lower Mississippi River, mile 8-13 above Head of Passes, can be viewed on the pre-removal multibeam surveys using these links.
Links to the latest bank-to-bank singlebeam surveys with bypass channel:
| South and Southwest Pass | |||
| Survey title | Survey date | ||
| Index number River mile | XYZ | SHP | Southwest Pass (MLLW) |
| Sheet 1 | 09/27/2023 | ||
| SW_01_SWP MM 13.4-10.5 AHP | XYZ | Shape | |
| Sheet 2 | 09/25/2023 | ||
| SW_02_SWP MM 10.5-7.7 AHP | XYZ | Shape | |
| Sheet 3 | 09/27/2023 | ||
| SW_03_SWP MM 7.7-4.8 AHP | XYZ | Shape | |
| Sheet 4 - Cubit's Gap | 09/27/2023 | ||
| SW_04_SWP MM 4.8-2.0 AHP | XYZ | Shape | |
| Sheet 5 - Head of Passes | 09/27/2023 | ||
| SW_05_SWP MM 2.0-1.0 AHP | XYZ | Shape | |
| Sheet 6 | 09/28/2023 | ||
| SW_06_SWP MM 1.0-3.7 | XYZ | Shape | |
| Sheet 7 | 09/28/2023 | ||
| SW_07_SWP MM 3.7-6.7 | XYZ | Shape | |
| Sheet 8 | 09/28/2023 | ||
| SW_08_SWP MM 6.7-9.6 | XYZ | Shape | |
| Sheet 9 | 09/28/2023 | ||
| SW_09_SWP MM 9.6-12.4 | XYZ | Shape | |
| Sheet 10 | 09/28/2023 | ||
| SW_10_SWP MM 12.4-15.2 | XYZ | Shape | |
| Sheet 11 | 09/28/2023 | ||
| SW_11_SWP MM 15.2-18.0 | XYZ | Shape | |
| Sheet 12 | 09/28/2023 | ||
| SW_12_SWP MM 18.0-21.0 | XYZ | Shape | |
| Sheet 13 | 09/12/2023 | ||
| SW_13_SWP MM 19.2-22.0 | XYZ | Shape | |
| Offshore Dredged Material Disposal Site | 05/03/2023 | ||
| SW_00_ODS Offshore | XYZ | Shape | |
| Pilottown Anchorage Area | 08/16/2023 | ||
| SW_00_PTA MM 6.8-1.5 | XYZ | Shape | |
| South Pass (MLLW) | |||
| Sheet 1 | 07/19/2023 | ||
| SP_01_SPS MM 0.0-1.0 | XYZ | Shape | |
| Sheet 2 | 07/19/2023 | ||
| SP_02_SPS MM 1.0-3.5 | XYZ | Shape | |
| Sheet 3 | 07/19/2023 | ||
| SP_03_SPS MM 3.5-6.5 | XYZ | Shape | |
| Sheet 4 | 07/19/2023 | ||
| SP_04_SPS MM 6.5-9.2 | XYZ | Shape | |
| Sheet 5 | 07/19/2023 | ||
| SP_05_SPS MM 9.2-12.1 | XYZ | Shape | |
| Sheet 6 | 07/19/2023 | ||
| SP_06_SPS MM 12.1-Gulf | XYZ | Shape | |