Avoiding Debris

[PNWTX]

Hello!

Just curious if anyone has any tips for watching for debris (primarily logs around here)? I mean other than the obvious "look with your eyeballs"? Are there tidal, weather or seasonal factors that make things worse?

Also, with these boats, they seem to be built well, so how large is too large? Should I panic if I accidentally go over a 3" diameter stick doing 30 mph?

Any advice or guidance would be appreciated. I love being able to go fast with the outboard, but it sure makes those logs more scary.

Thanks!

 

[Cutwater28GG]

big storms make it worse + high tides and logs get washed off beaches etc. the tide lines are the worse places for them as it aggregates the flotsam into impenetrable lines

 

[scross]

My experience over the past 7 years is that as you move north, the debris problem gets worse. Much more of a problem in the Gulf Islands and Sunshie Coast than in the San Juan’s. Vancouver near the Frazier River is bad too.
In some areas, especially along tide lines, it becomes a realistic goal to maneuver in a way to hit only the smallest pieces at slow speed rather than the impossible task of being able to avoid everything.
You need eyes open and really slow way down! As a friend once advised about off roading in a wheel drive: there’s a really big difference between going 3 mph and speeding along at 6 mph in rough areas.

 

[Beardco]

Holy moly, a 3" stick is more like a branch; and at 30mph? Fiberglass is flexible but, that's going to sound like a shotgun blast and definitely do some gelcoat damage. When I see that stuff, I slow down to 5 knots.

 

[FlyMeAway]

I don't know if our boats have this, but is the high-end radar that is supposedly capable of seeing seabirds sitting on the water any good at detecting floating logs? I'd imagine even a half-submerged log as *some* radar signature...?

 

[scross]

Sorry, depending on every log having a bird perched on it is not going to help. Sure, occasionally there’s a bird on a log but it’s pretty rare overall. The solution to debris is to go really slow anytime you start to see stuff in the water. And by slow I mean well under 10 mph. Sometimes that means going slow all day.

 

[FlyMeAway]

Sorry, depending on every log having a bird perched on it is not going to help. Sure, occasionally there’s a bird on a log but it’s pretty rare overall. The solution to debris is to go really slow anytime you start to see stuff in the water. And by slow I mean well under 10 mph. Sometimes that means going slow all day.

I think you misunderstood my question. There is no substitute for watching the water. But if radar can detect a small bird sitting on the water, or something the size of a crab buoy, why wouldn’t it also be able to detect a log (which is larger).

Nothing I what I wrote assumed a bird was sitting on the log.

 

[Chriscz128]

Definitely watch the eddy lines created by the tides, especially around convergent current from different waterways. These areas will always accumulate the most floating debris. Even if you can’t see logs or large material, if you see eelgrass, kelp, even foam, these are areas to be more careful in. During slack tides all of the accumulated material is released and more dispersed so more difficult to spot. As other have mentioned, larger high tides and storms mobilize materials off of beaches so look at recent history. Also watch out after large rain events and high river discharge times which bring new material down from the surrounding watersheds.
All that said, I just hit a chunk of wood the other day, didn’t even see it, only heard the impact.

Chris

 

[Chimo]

Maybe time for an ‘in the mirror’ reality check?

Generally we are all getting older. The alternative means this question is irrelevant. When much younger I have been in a boat at 170 mph. I have driven a boat at 105 mph. It’s incredibly stressful but really exciting. As I grew older I settled for a deep V and a cruise about 45 mph. When I moved back to the PNW I recognized all the junk in the water and the need to relax a bit. I owned a 23 C-Dory with twin 60 hp Yamahas. Cruise was in the mid-20’s. One day in a 2-3 ft chop I went over a log that I didn’t see. Both the outboards kicked up but I took out my depth sounder. If I’d been younger I might have seen it. I’d have had a better chance at 15 mph.

So then I bought a RT25SC. I cruise around 15 mph and I recognize that a high tide pulls stuff off beaches. Tides bring stuff together and if you see one log it probably has a friend so slow down. The RT is well enough built to shoulder stuff aside at low speed but hull impact is a function of speed^2. My marine engineering background taught me that.

It’s like driving a car. I’ve driven a lot on the autobahns and for years regularly hit the 240 km (150 mph) limiter when I was younger. Today, or rather in 2019 pre-COVID, I find 190 km (120 mph) to be comfortable. As we get older our reactions slow significantly. To answer the question about hitting a 3” log the answer is “It depends”. Will you survive, the answer is probably “yes”. Will you do damage? Maybe. Can you be sure it’s only 3” and not 5” before you decide to hit it? Unlikely.

In short, if you’re younger and richer, go for it. If you hit an 8” deadhead with only 2-3” above the surface and 10’ below at 25 mph just remember that e=mc^2.

 

[knotflying]

See and avoid! Can you do that going fast?

 

[Maggie Anne]

To respond to the question about radar identifying logs, I have observed that on foggy days with calm seas that I've been able to clearly see crab trap buoys using radar but have never identified a log using radar. I think it would be mostly ineffective, especially as the seas pick up.

 

[CaspersCruiser]

I have observed that on foggy days with calm seas that I've been able to clearly see crab trap buoys using radar but have never identified a log using radar.

At what range setting do you see crab trap buoys displayed on your radar and how large is the return? When I’m cruising the Ohio River using radar on a half-mile range setting, large channel navigation buoys equipped with radar reflectors show on my radar display about 1/4 the size of my pinky fingernail.

 

[SJI Sailor]

Agreed with all the above and would add this: watch out and slow down when going into the sun.

The worst log experience we've had was returning from San Juans through Anacortes and the Swinomish channel. The morning sun and then South winter sun was in our eyes for more than four hours and made it very difficult to avoid the many logs that were in the Swinomish channel (we hit two that were completely submerged, but at slow speed, no damage). Almost enough to make me prefer clouds, maybe a good thing around Seattle!

As for radar, I've not been able to tune ours well enough to discriminate logs from sea clutter. Seems like that would be a very fine line in the PNW. OTOH, I also have only tried a few times, since I figure if I'm concerned about that, I should just slow down.

 

[pleeson]

The day you almost hit one of those far too prolific waterlogged vertical barely floating full tree size deadheads that are either barely making an appearance or wholly below the surface and realize how lucky you were not to hit it, will likely be the day you reassess the importance of going 20 - 30 knots in these PNW waters. I've seen my share of deadheads up the inside passage that have clearly made contact with other boats and propellers. I think if you hit one of those at speed you are going to be praying that your bilge pumps can keep up. As for radar signature - HA! Last close call I had with one of those was last fall. I was fortunate enough to be in zero zero fog conditions on a flat calm doing only 5 knots. Radar zoomed in and showing even inflatables and kayaks but not a chance on the woody debris. The big broken ended 2 foot diameter log just slipped by on the captains side and was virtually fully submerged. I could see it disappearing into the depths, it probably weighed thousands of pounds. I didn't see it until the bow had already passed it. Would not have been pretty at speed and a few inches over towards the port side. This winter massive landslides that travelled many miles brought down millions of tons of rocks and debris in at least two inlets here in BC, one feeding into popular Desolation Sound. All logging roads and bridges were destroyed and the valleys were completely stripped of trees and soil. If Covid restrictions lift, visiting boaters better beware. Those disasters will translate into boater hazards for years to come.

 

[FlyMeAway]

To respond to the question about radar identifying logs, I have observed that on foggy days with calm seas that I've been able to clearly see crab trap buoys using radar but have never identified a log using radar. I think it would be mostly ineffective, especially as the seas pick up.

Thanks. This is what I was curious about. Never had the radar good enough to identify crab traps before (and honestly not sure if the radar on my newish-to-me tug is good enough for that in any event). This is helpful.

For other people who have been asking: I’ve seen this demoed by Raymarine, Garmin, and B&G/Lowrance — radar that picks up crab traps (navigation) and seabirds (for fishing). The latter was a really big deal (according to my fishing friends) when it first came out.

 

[Cessna172]

Another consideration I have experienced when using radar is the speed I am traveling.

In the fog and calm waters, I am travelling 5 - 7 knots. The radar clearly defines objects from the water's surface and higher. However, traveling at planing speeds creates a very different scenario.

While planing the stern is dug in and the bow is up in the air. The radar lowest level of returns seem to be much higher than when at hull speed. In fact, this past Saturday while cruising north in Puget Sound at 18 knots, a 28 foot Bayliner less than a 1/4 mile directly in front was invisible to the radar. Once it past by the starboard it showed up on radar.

If this is the case, that the radar unit's tilt while planing significant reduces the forward view at the water's surface and even higher (Bayliner story above); then, any chance of detecting logs, traps, etc. barely above the surface while planing is probably not going to happen.

 

[bob daily]

Your Garmin radar has a band with of 25 degree , 12.5 above and 12.5 below horizontal. And needs to be shimed so it is mounted level at the speed you usually curse at! IAW the installation instructions.
Due to the up angle of your boat you were shooting over the top of the bayliner till passing him.
I can pick up crab buoy and small floating object with radar at minimum range but sea has to be like glass, which is almost never! Also remember the minimum distance of the Garmin radar is about 65 ft.
The question is not IF your going to hit something, but WHEN and how much damage it will cause!
To me traveling across some bodies of water going over 15-20 MPH is like driving at night with your headlights off! Why take the chance? Bob

 

[yorangerjim]

Very helpful
Thanks !!

 

[H28]

In 35 years of boating on Lake Michigan I never worried about logs. Then a few years ago I was running up north (Up north where they have rivers flowing into the lake as opposed to Chicago area where the Lake flows into the River) a few days after a huge storm. Hit a log. $900 to straighten out the prop. Learned my lesson...... a sharp lookout is your best defense...

 

[TwoFootitis]

What about forward looking sonar?