I watched helplessly as the sailboat approached the bridge. I could see from where I stood that they couldn’t make it under but they were steaming straight for it as if they didn’t have a care in the world. At the last second the boat turned sharply to port but it was too late. The one and a half knot current carried them under. They made it half way before the mast got stuck on one of the girders under the bridge with the boat healing at about 30 degrees and the tide rising. Fortunately about 20 minutes later a runabout came by and between it and the help of the current, they were dragged the rest of the way under and out the other side.

It’s stories like this, absolutely true by the way, that may be the reason that very few sailboaters attempt to go under the Hartstene Island Bridge. The other reason is that many don’t understand what bridge clearance really is. Water depth is measured from 0 down to the bottom. 0 tide is the Mean Lower Low: that is the average of all the lower of the two lows of each day. Bridge clearance is measured from the Mean Higher High which in the Olympia area is a little over 12 feet. I round it down to an even 12 feet to be on the safe side. On the charts the clearance of the Harstine Island Bridge is shown as 31 feet. This means that at a +12 foot tide there is 31 feet under the bridge to the water. It also means that at a 0 tide there is 43 feet of clearance (31+12) and for the extreme of a –3 foot there is a clearance of 46 feet. (31+12+3)

So, if it’s less than 46 feet from the tip of your antenna, or whatever is the tallest thing on your mast, to the water and you read the tide tables very carefully, you too can make the pleasant trip up Pickering Passage and enjoy the shortcut to Jarrells Cove. By the way if you see some idiot waving frantically from the shore shortly after you’ve made it under, it’s probably just me. I hope to see you out there, and all in one piece.

Jim Findley Skaga / Not Sirius