The Lead Line



Anchorage outside Cap Sante Marina, Anacortes

For a change of scenery, Leonard decided to anchor just outside Cap Sante Marina while awaiting my return from Portland.  It turned out to be a scenic anchorage with great views of Mt. Baker, plus a convenient dinghy dock for going ashore.  

Got d' Fever at Anacortes Anchorage

Minus tides for that entire week, however, were predicted for the area.  On his second morning while at anchor, an extreme low tide would occur.  The charted depth for the area is 8 to 9 feet at zero tide, and the tidal prediction had called for a minus tide of about 2 feet.  Our boat has a draft of just under 5 feet, making for a rather close encounter in this particular situation, leaving only 1 or 2 feet of water under the keel.  Leonard monitored the “depth sounder” but these electronic readings can have errors or anomalies due to the different layers of mud and seaweed under the water creating less than precise readings.  

Looking towards Cap Sante Marina

The location of the transducer (the device that transmits the electronic readings) has to be taken into consideration as well.  The transducer is not normally located at the bottom of the keel but somewhere part way up the hull, accounting for another margin of error.  Then there is the tidal prediction which is taken from a nearby “tidal station” which isn’t necessarily where the boat is located - another possible margin of error that could result in more or less water under the boat than anticipated. 

Looking towards Mt. Baker

In order to figure out exactly how much water he had under the boat at any given time, Leonard created a “lead line” – a common practice used by early mariners.  

Leonard's Lead Line

To create his lead line, Leonard used a downrigger fishing weight and attached a thin rope or line marked off in 3 foot intervals with painters tape.   His lead line confirmed that the charted depth was accurate and that the tidal predictions were correct.  He was confident that there would be nearly 2 feet of water under the keel before the tide would change again to more comfortable levels within a half-hour.  The use of this old technology had paid off.