Taming Great Bras d’Or’s reversing tidal whimsy

To the editor: The Bras d’Or Lake of Cape Breton, Nova Scotia, is a prime sailing destination. Most visiting crews sailing down east enter the lake through St. Peters Canal on the west end. However, we approached from the Gulf of St. Lawrence. We would just come into the lake from the east through the Great Bras d’Or Channel. No problem, we thought.

But the peculiarities of the channel, we learned, make the passage tricky to say the least.

Since commercial and fishing craft pass it frequently, the channel is well marked with large, lighted, radar reflecting buoys and range markers. The entry is straightforward except for the fact that the tidal current slews across the narrows and at its maximum boils along at up to 6 knots. We intended to avoid that turmoil and simply arrive within an hour or so of slack water.

With dismay, we learned that the time of slack water cannot be reliably fixed. Tables that purport to give these times are notoriously unreliable. Moreover, the direction of the current in the channel is counterintuitive. That is, the current floods most of the time the tide is falling and ebbs most of the time the tide is rising. Furthermore, winds blowing up or down the channel can retard, advance or even reverse the “normal” flow pattern.

How in the world could we cope safely with all this tidal whimsy? We didn’t like the idea of just taking pot luck, and our initial inquiries were not encouraging. Eventually, we encountered a delivery captain whose good sense and experience gained our confidence. Capt. Hamilton Carter had passed through the entry numerous times. His formula seemed to be just the tonic we needed:

“To be sure the current is with you – or at least not strongly against you – going in, arrive at the entry two to three hours after high tide. Going out of the channel, arrive at the exit two to three hours after low tide.”

The captain’s formula works unless a strong SW or NE wind has been blowing for some time in the channel, in which case prudence dictates waiting until the weather and the channel settle down. The time of high or low tide can be obtained for any nearby location in Cabot Strait.

We personally experienced the unpredictability of the Great Bras d’Or. We came to the narrows in our Baba 30 cutter ahead of rapidly deteriorating weather. We were in a hurry to get through the channel to tie up at Baddeck in the lake. We decided to push the formula and try entering just one hour after high tide, in this case, about 1130.

We contacted the Sydney, Nova Scotia, Coast Guard, who will give times for slack water and maximum current from the tables on request. Although we knew we could not trust this information, we wanted to see just how far off it might be in a specific instance. They quoted 1232 for slack water and 1500 for maximum ingoing current. Thus, according to the tables, we should have seen a small outgoing current against us with an hour to go to slack water. In fact, we had 2 to 3 knots in our favor going in. Not even close!

Two hours after high tide we would have had, at worst, a small outgoing current to contend with. As it happened, a fair current propelled us happily through the channel before the adverse weather got going.

Jim Hawkins and Ellie Adams are semi-retired psychologists from Minneapolis who sail their Baba 30, Meta Fog, on Lake Superior and next are headed for Newfoundland.

By Ocean Navigator