Join Date: Mar 2007
Location: New England
Thanked 7 Times in 7 Posts
Rep Power: 10
How Much water- Part Deux
Went to the boat today. At today's low tide, I did the plumb bob string measure technique in several areas around the boat. My measurements were around 11' give or take a few inches. The sounder was reading 9.4 feet. So my original guess of the transducer being about 1.5 below the waterline was about right assuming it is accurate for it's hull location
Today's low tide was theoretically 1.5 feet above MLLW, so I guessing at MLLW I am in about 10 feet of water. According to the harbor chart, the extreme LLW is -3.5 feet, so if that is the case, that puts me in 6.5' of water for a 5' 11" draft. So I have 7" of draft at the extreme low tide assuming no waves. The area that I am has a sandy/muddy bottom, so that is a plus. I am also pretty far into the harbor, so exposure should be lessend. The harbor is surrounded by high land on three sides. The fetch distance to open water is about a 1400 yards, whereas the nearest shore is 300 yards and the other shore is 900 yards. The closed end has a depth of 4' or less at MLLW for most of the area (1500 X 1200 yrds). Distance from my position to the area where the depth is 4' or less is less than 300 yards.
I looked at the tide charts for the next three months, (the boat is pulled by then) and the lowest tide is -2.0 ft, so that is around 8 ft or 2 ft of clearance.
I think I am probably pretty safe, but tomorrow I am going to put a call into the harbormaster to see if I can get in a little deeper water. If not this year, hopefully next. I will ask for at least 12 ft at MLLW, which should be more than plenty even in extreme conditions.