GL: Eastern Erie Canal bridge clearance

[MichaelZ]

> .....and the eastern Erie and
> Oswego canals allow around 22 feet.
> Fred
> Tug 44


The Eastern Erie Canal (that portion east of the Oswego Canal) has a 
clearance of 21', not "around 22 feet". There are seven bridges lower than 
22', the lowest with just 21.37' at Normal Pool. That leaves about 4" of 
clearance if your air draft is 21'... not much! ...and don't forget to 
factor in wave or wake action. Pool is the height of the water in a 
controlled environment such as a canal. Normal Pool is the target and the 
usual height of the water. At (defined) Maximum Pool this bridge would have 
clearances of only 19.37'. The canals are usually at Normal Pool, but recent 
rainfall, seiche, or other factors may change this. If needed, ask each 
lockmaster as you pass through if the next leg is at Normal Pool (Pool level 
may vary each time you lock through); also check the Notices to Mariners on 
the NY State Canal System website for any updates.

You can measure your air draft by using a level and something long and 
straight such as a boat pole or a 2 x 4. First measure from the highest 
point to a specific place on deck (usually on the centerline of the vessel). 
Tape the level to the straight piece, then, using the straight piece placed 
at the point on deck where you measured from the top of the mast (or 
whatever), run the straight piece out athwartship, adjusting it level and 
measure from it to the water. This is, of course, much easier to do with two 
people. Measure two or three times on both sides of the boat to validate it. 
Do it again if your mast/antennas/bimini can be lowered so that you know the 
air draft of each configuration. This should be done when the boat is near 
empty of provisions, fuel, water and waste and then again with a normal 
heavy cruising load aboard. My own 39' boat can vary about 8" in air draft 
between the two load levels. Also, don't forget the fore-and-aft factor. 
Biminis or hardtops can be higher (usually forward) at one end from the 
other.

Fair winds and calm seas,
MichaelZ