Water Depth Under Bridges

[tclC-18]

I am sailing a Catalina 18 in the relatively shallow waters of the Caloosahatchee River around Ft. Myers, Florida. There are a number of bridges in the area, and the NOAA charts seem to show that, generally, where these bridges are located, there is adequate water depth for my boat (which draws only about 2.5 feet). I am confident that I have ample water depth in the main channel under the central span of these bridges.

My question is this. Because the NOAA charts do not indicate any special water depth limits or obstructions under any portions of the bridges, can I assume that the water under the other spans of the bridges is what the NOAA chart is otherwise showing for that part of the river? Or do I need to be extra careful about using anything other than the main channel under a bridge, even though the chart does not show any special depth limitations under other parts of the bridge?

Thanks.

 

[Charlie Jones s/v Tehani]

I ALWAYS use the main channel. Have never worried about water depths, but that's the highest air draft.

Never had a problem with any bridge in the Ft Myers area. I draw 3'6"

 

[31seahorse]

Hello tclC-18,
Old Saying......The Caloosahatchee is a mile wide and a foot deep. Without a depth sounder I would be very cautious about straying far outside the channel at the bridges. We have sailed a Precision 18 outside the main parts of the channels, but then the mud was the only real concern. Other obstacles include the bridge clearance, floats and traps, etc. Of course you could proceed with caution or even under OB power to investigate those areas, or go there by kayak first. Plunge a paddle down to check depth. Enjoy. 31seahorse

 

[woodster]

old river rat trick is...... always look for the high bank.....when in doubt about the depth of the water in the river ...but i suspect that river is without high banks

 

[Crazy Dave Condon]

On the ICW and along other waterways, many bridges are marked with high and low water marks to help boaters. Woodster also gave good advice about watching the terrain but then again there are hidden shallows and underwater obstruction.

 

[kloudie1]

Water depth is same as either side unless there IS a problem.. then that would be shown.. so yes, you can use either side or middle as long as your air gap is sufficient and no shoals are indicated on either side.

 

[tclC-18]

On the ICW and along other waterways, many bridges are marked with high and low water marks to help boaters. Woodster also gave good advice about watching the terrain but then again there are hidden shallows and underwater obstruction.

Thanks to everyone for the helpful responses.