Harbor Depths

Grassy Island lakeward to entrance light: 11.5 miles

• Maintained at 26' below low water datum.
• Channel width is 500'

Grassy Island to the Mason Street Bridge (Mile 2.25)

• Maintained to 24' below low water datum
• Channel width is 300'

Mason Street Bridge (Mile 2.25) to Georgia-Pacific turning basin

• Maintained to 22' below low water datum
• Channel width is 300'

• Navigation channel from Georgia-Pacific to De Pere Dam is no longer maintained.
• Low water datum is 577.5' above mean level at Rimouski, Quebec, Canada.