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Lightning protocols for river trips....


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Been reviewing NOLS, and a few other sources on this subject as part of updating our Trek's float plan. If there is one, unpeachable fact about lightning is that it is unpredictable.

 

As such, let me toss three questions your way for your thoughts.

 

When should activities be stopped?

 

Where should your crew go for safety?

 

When should activities be resumed?

 

 

 

 

 

 

 

 

 

 

 

 

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le V,

I was just reading about that very subject in two of my Cliff Jacobson books, Canoeing & Camping, beyond the basics, and Canoeist's Q & A, Scenarios for Serious Canoeists. He warns against going to shore if it is lined with the tallest trees around, or if the shoreline is rough, as in lined with bolders or steep cliffs. If the shoreline is clear, then get off the water.

 

He mentions a lightening-protected zone that extends from the tops of the tallest trees (or other geographic features) outward about 45 degrees in all direction. He recommends paddling within this safe "cone of protection" but not so close to its center that lightening may jump from a tree to you. He says lightening can easily breach 10 or 30 feet, so stay 50 - 100 feet offshore. He claims that is the safest place to be, if you can't get to shore safely, away from the tallest trees.

 

If you hear a storm approaching, start making plans. Track the approach of the storm by counting the seconds between strike and thunder, and divide by 5 for miles away. I think the decision for when to stop depends on the speed at which the storm is approaching. The lifeguards at our pool get everyone out as soon as they hear thunder, and won't allow anyone back in until there hasn't been any thunder for 20 minutes. That may be a little overkill if on a trek, but it would be pretty safe. Sorry I don't have a straight answer, but that's part of why I'm reading the books. :-)

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When I did my two 50 milers, when we first heard thunder, we started looking for a place to pull over. First go around, we were not able to get out the lake before we saw lightening, but we then began paddling so fast,a skier could have been attached to the stern painter ;)

 

Second trip, not with BSA but with Eckerd Foundation, we saw lightening, immediately pulled over, and lucked out that there was a river house that was open.

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Yah, depends on da river, eh?

 

I know that the protocols for many of the whitewater guide companies are to stay on the river and away from shore. Rivers are about the lowest spot around, eh? Especially when you're in a rubber raft or plastic kayak. Safer than gettin' out on shore.

 

I read through a lot of stuff after that odd boy scout lightning fatality out east with da lawsuit and settlement. Close as I could tell the rule should be do what's obvious...

 

1) If there's a hardened grounded structure around, go in it.

 

2) If you're the tallest thing around, be somewhere else.

 

3) If you're next to the tallest thing around (or a long conductor), be somewhere else.

 

4) If you can't be somewhere else, spread out, crouch down.

 

Beyond that, it ain't worth worrying about. The rest is just part of da background risk of being in the outdoors.

 

Close as I can tell, all the other advice is either false, unverified, or useless. The 45 degree cone of protection thing doesn't work, lightning can come well in advance of rain or thunder (the bolt that got the scout originated 18 miles away), it does somethin' fairly close to a random walk.

 

Beavah

 

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That's about as clear a set of lightning safety instructions as I've ever found ... and I think it is dead nuts correct.

 

Before my son's troop went on their river trip I did a LOT of searching and reading and it really did boil down to Beavah's list. I might add: If you're on a body of water (river/lake/...) get off.

 

Then there is the "stay put until 30 minutes after the last thunder is heard".

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Beavah's rules make the most sense.

Most boating/lightning incidents occur in open water, away from trees where you are the tallest object and easiest path for discharge. Most fatalities occur in open boats without cabins. If you detect lightning and are in open water, move towards shore. If there's shelter on shore, move to it. Lightning is lazy. Try not to be the easiest path of conductivity. Being on the water isn't necessarily the worst place. Being the tallest thing for hundreds of yards around is. I've heard the 45 degree rule too, baring any contradictory evidence, I'd follow that too.

 

I seriously doubt the material of the canoe or raft (rubber/wood/aluminum/plastic) will have any significance on the likelihood of a strike. Urban myth is that the rubber tires on a car make you safe. Actually, its being surrounded by medal that makes you safe. A Faraday cage. Gives the energy a path around you. With the amount energy discharged, materials have two choices, conduct or vaporize.

BTW, sailboats also make a great Faraday cage. I know personally. We were racing on a high mountain lake when a sudden storm hit us. We took a bolt to the top of the mast. Instantaneous shock and awe. Which traveled down the shrouds to the hull and keel (we had properly grounded our shrouds to the keel bolts). I was at the helm. The smell of ozone was powerful. A quick check to the integrity of the hull showed no damage. Another boat in the marina was not so lucky. A bolt blew a hole the size of a golf ball through the hull and sank her in her mooring.

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