Great Loop bridge planning reference

Southern Harlem Avenue Bridge

Southern Harlem Avenue Bridge on Chicago Sanitary & Ship Canalnear Lyons / Forest View, IL; closed clearance about 24.9 ft. Low fixed/nonopening bridge.

41.81000000, -87.80400000

Fixed bridge
WaterwayChicago Sanitary & Ship Canal
Route SegmentIllinois / Chicago
Route VariantInland Rivers / Chicago or Cal-Sag
State / ProvinceIL
Nearest CityLyons / Forest View
Mile MarkerRM 314.0
Bridge TypeBascule listed does not open
Source Confidencemedium

What Boaters Should Know

Southern Harlem Avenue Bridge on Chicago Sanitary & Ship Canalnear Lyons / Forest View, IL; closed clearance about 24.9 ft. Low fixed/nonopening bridge.

Clearance And Opening Details

Vertical Clearance Closed24.90 ft
Vertical Clearance OpenNot verified
Horizontal Clearance140.00 ft
VHF ChannelNot verified
PhoneNot verified
Last Verified2026-06-08
Verify against current water level / bridge gauge before transit.

Opening / Contact Notes

Opening Schedule
Does not open per USACE table.
Operator / Contact
Not verified

Navigation And Regulatory Notes

Air Draft Notes
Closed/air-draft clearance: 24.9 ft. Datum/reference: Low Operating Level / Flat Pool; NGVD 1929. Clearance band: Low / Timing-sensitive
Navigation Notes
Does not open per USACE table. Verify current status; table lists bascule but open clearance as does not open. Closed/air-draft clearance: 24.9 ft. Datum/reference: Low Operating Level / Flat Pool; NGVD 1929. Clearance band: Low / Timing-sensitive Does not open per USACE table.
Regulatory Notes
Does not open per USACE table. Verify current status; table lists bascule but open clearance as does not open.

Planning Considerations

Confirm your vessel air draft, current water levels, bridge signage, official charts, bridge schedules, Local Notices to Mariners, and any VHF or phone procedures before approaching this bridge. If the bridge is movable, build extra time into your route plan for opening windows, traffic, restrictions, weather, and communication delays.

Planning awareness only: Bridge information is provided for planning awareness only. Always verify current bridge status, clearance, water levels, bridge schedules, opening restrictions, Local Notices to Mariners, bridge signage, and official charts before transit. FloatPlanWizard is not a navigation authority.