Sunday, June 15, 2014

We’re still alive, still afloat

Despite the dire predictions of friends and guidebooks we made it through Rocky Pass.  The stakes went up considerably when Jon & Jennifer on Captain Kidd decided they were going to follow us through.  Its one thing to be responsible for our own boat but two additional souls plus their (very nice little) Krogen yacht upped the stakes considerably.

We took it very slowly but that turned out to be absolutely unnecessary.  The whole pass is maybe 10 miles at most and it could easily be run in a single day as long as you did it at high tide.  We ran the north end – what is referred to as “The Summit” - on a 14 foot tide and I saw 14 feet on the depth sounder a couple of times.  That means that on a zero tide there would be – you guessed it – zero water – in those spots.  Its actually even worse than that because the Americans have a different way of measuring tide levels.  In Canada the “chart datum” or point where tides are measured from is the average of the LOWEST low tides.  In the US the datum is the average of the low tides.  In practice that means that you never see a minus tide in Canadian waters but you routinely see minus 3 or 4 foot tides in US waters.  So that 14 feet that we saw on a 14 foot tide could easily become 2 to 4 feet of dry mud on a minus tide.  Absolutely not any place you would want to be with a boat that draws 4-1/2 feet.


Captain Kidd at anchor north of “The Summit”.  From Gray Hawk they looked like they were on the bottom but Jon assured us they still had 8 or 10 feet of water underneath their keel.

We ran the northern section - “The Summit” - yesterday and anchored between The Summit and “Devil’s Elbow” last night.  Then we ran Devil’s Elbow starting at 6:00 AM this morning (4:00 AM local – which was a stretch for Jon & Jennifer).  We did that in order to hit both sections as close to absolute high slack as possible, but that level of caution clearly was not necessary.  We absolutely needed to hit both of the tricky bits at high slack but the whole pass is so short that we could run both of the skinny parts in slightly over an hour.  So we could easily have come into The Summit an hour before high slack and been out of Devil’s Elbow before an hour after high slack.  As it turns out the pass floods from both ends which means that by timing our passage immediately before and after high slack we could have been flooded into the north end of the pass and ebbed out of the south end.  On the other hand, the entire length of the pass was ruggedly beautiful so it was no hardship to anchor midway.  We could easily have spent a week moving one or two miles between anchorages inside the pass every night.  On future trips that is likely exactly what we will do because there are many potential anchorages and we only saw one boat through the whole pass.


Pictures don’t really capture just how close those rocks are.  There was one point where there was a green marker followed by a red marker followed by another green marker, all of them within about maybe 300 yards total distance.  The correct route was an S-curve around all three markers but it was really REALLY important to go the right way around them.

When we popped out the south end of the pass this morning it was with a tremendous feeling of achievement.  But it really isn’t that big a deal anymore.  The charts we were using were printed in 2011 so they’re about as current as they can be.  The guidebooks that cautioned about the perilous nature of Rocky Pass were printed 8 to 10 years ago.  Some of them refer to the “new” technology of GPS navigation. 

There’s still no substitute for looking out the window but GPS charting has been a game changer.  Twenty years ago we were using soap and water to mark passes with our high clearance floaters and sprayers.  Our equipment was state of the art – we even heated the water so that it would make better, longer lasting foam.  Today everyone – and I mean EVERYONE – who is serious about custom application uses GPS.  Its been nothing less than a revolution in guidance.  Not only custom applicators but most farmers use GPS guidance for seeding and spraying.  Applicators can drive within 4 inches on 70 foot wide (or wider) equipment so guiding a 14 foot wide boat through 150 foot wide channels really isn’t much of an accomplishment. 

As long as the charts are accurate and the equipment doesn’t crash, the operator just has to keep the little red boat between the lines.  We run two completely independent GPS systems.  They use identical Garmin antennas for redundancy but there is no interconnection between the systems so neither system depends on the other.  One antenna drives the Garmin chartplotter; the other drives OpenCPN on our widescreen all-in-one computer.  As long as all that technology works its really pretty simple.  I didn’t let the computer actually do the driving through the skinny bits but as soon as we popped out the south end I relinquished control to the computer and it drove us all the way back to Coffman Cove.  I’m pretty much just a passenger at that point.

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