# Utilizing Google Earth in Navigation



## RegisteredUser (Aug 16, 2010)

Who is making use of this, and how are you using it?
I'm a puter dummie and don't understand much of what is now available.
I did find SAS Planet, purportably helpful for nav. I've not yet messed up my computer trying to use it....

I've played with GE for several years and think it's great, and have read reports of people making use of it for nav in remote/poorly charted places.

Experiences...rumors...?


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## Arcb (Aug 13, 2016)

Real time navigation or passage planning?

I'm working on a YouTube vid on how I use it for passage planning right now.

It's got some great features including save able maps called My Maps where you can store planned routes to work on later, or save on your hard drive for later use.

Google maps will also calculate really easy great circle routes for you too. 

Of course you can toggle to satellite imagery which can give more accurate indications of bottom contours and bottom type than a chart in a shallow/poorly charted area.

I've been using it extensively for an upcoming trip in February. Conventional charts just don't have the granularity for navigating a boat with a 12 inch draft for maximum efficiency in very shallow areas.

If you are talking about using it for real time navigation/pilotage- I am hoping to learn more, I don't know how to do that.


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## capta (Jun 27, 2011)

When I had to move the boat alone to a dock in East Greenwich for the winter, I Google earthed the cove and identified the marina and the dock I needed to tie up to. As there were several marinas side by side in the cove, I never would have had nearly as clear a picture of where my dock was or which marina was which, from a chart or the chartplotter.
But I've been using aerial views of passes into harbors and through reefs and reef strewn coastal waters since the mid 70's. First I discovered color picture postcards of many of the passes and harbors of the SoPac islands I intended to visit, and soon after that I found out that the United Kingdom Hydrographic Office had aerial photographs of nearly every inch of many of the island groups in the SoPac, and that copies were free for the asking! Even areas that were just blank white space on the official government charts, were beautifully presented for my navigational needs in these aerial photographs. A hearty thank you to the United Kingdom Hydrographic Office.


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## colemj (Jul 10, 2003)

We use satellite images for navigation (GE isn't the only one providing images). There are a few ways of doing this. SAS planet is well-liked, but I've never used it because it is poorly documented and mostly in Russian. However, everyone tells me it is easy to use.

I use GE2KAP a lot to make charts from images: Sample

OpenCPN has the ability built-in as a plugin to grab satellite images and make charts from them automatically.

SeaIQ on iOS/Android devices uses Venturefarther and also automatically makes charts from images.

Of course, you can do this directly from Venturefarther: https://www.venturefarther.com/kap/Charting.action This used to be free, but now they charge a small amount to use.

Because these programs create georeferenced charts in a format most charting software can use, they can be used for real-time navigation. The transparency level can be adjusted in some programs (like OpenCPN) so that they can be superimposed on the navigation charts.

Mark


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## mthoma21 (Mar 2, 2017)

I have been using Google Earth considerably more this past year to navigate instead of traditional charts. They updated the area around Cape Lookout and Oriental in 2017 with new images and I didn't take my boat too far from home this year so I knew most of the dredged channels. The finding the correct slip in new marinas and gunkholing around North Carolina in a 3' draft boat, it seemed more prudent to see where the shoaling was with pictures that were more up to date than the charts (like capta said). I never thought about combining them with charts on OpnCpn or similar programs, I need to up my skills I guess.


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## Yorksailor (Oct 11, 2009)

Mark, I got the google chart generator onto Open CPN but then I got stuck, it wants an API key in preferences. How do I get the key and preferences in which program?

Phil


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## hellsop (Jun 3, 2014)

RegisteredUser said:


> Who is making use of this, and how are you using it?
> I'm a puter dummie and don't understand much of what is now available.
> I did find SAS Planet, purportably helpful for nav. I've not yet messed up my computer trying to use it....
> 
> ...


Google Earth is hand for familiarizing yourself with what place look like, what facilities might be available close to wherever you get your dinghy tied up, and REALLY nice for seeing how landmarks line up. But it's REALLY lacking in the depth department and doesn't have information that is really useful for live navigation: no channel marks, no indication of permitted anchorage, no buoy or light info, etc. If you're looking for cheap options, OpenCPN with NOAA charts for on the water, Google Earth for on shore.


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## colemj (Jul 10, 2003)

hellsop said:


> Google Earth is hand for familiarizing yourself with what place look like, what facilities might be available close to wherever you get your dinghy tied up, and REALLY nice for seeing how landmarks line up. But it's REALLY lacking in the depth department and doesn't have information that is really useful for live navigation: no channel marks, no indication of permitted anchorage, no buoy or light info, etc. If you're looking for cheap options, OpenCPN with NOAA charts for on the water, Google Earth for on shore.


By the time charts created from satellite images become important, it is because none of those things you list as missing are available in any reasonably accurate chart.

Almost all of the areas we cruise in have no channel marks, indications of permitted anchorages, buoy or light info, etc. At most, we hope that the land is approximately where the charts say it is, and the depths are good to +/- 10' within accurate.

You missed the ability to overlay the satellite charts as a transparency layer on navigation charts. This tells oodles about where the actual land or reefs are, while the nav chart gives some loose information on expected depths. Most of the time, we are looking only to stay off reefs in difficult light/water conditions, and satellite images are pretty good at that.

Mark


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## Arcb (Aug 13, 2016)

hellsop said:


> If you're looking for cheap options, OpenCPN with NOAA charts for on the water, Google Earth for on shore.


Just for clarity, I don't think people are saying satellite images instead of published charts, rather satellite images in addition to published charts.

Here is a quick example. This link shows Stump Pass Florida with satellite imagery. The attached thumb nail shows Stump Pass on a NOAA chart.

https://www.google.ca/maps/place/Ev...b504533a!8m2!3d25.8582443!4d-81.3850695?dcr=0


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## hellsop (Jun 3, 2014)

colemj said:


> Almost all of the areas we cruise in have no channel marks, indications of permitted anchorages, buoy or light info, etc. At most, we hope that the land is approximately where the charts say it is, and the depths are good to +/- 10' within accurate.


Right. But that's you. Not the original poster who gave no indication of where they were cruising other than "TX/FL". Which have many many many channel markers, bridges, very fussy law enforcement perfectly willing to fine you for anchoring in the wrong places, and very good charts available, for free.


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## RegisteredUser (Aug 16, 2010)

My interest is in using it as a tool to better know reefs, reef breaks and landmarks for navigating in places with poor charts.
Pretty simple...pretty neat tool, imho.

The negatives = zero


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## colemj (Jul 10, 2003)

hellsop said:


> Right. But that's you. Not the original poster who gave no indication of where they were cruising other than "TX/FL". Which have many many many channel markers, bridges, very fussy law enforcement perfectly willing to fine you for anchoring in the wrong places, and very good charts available, for free.


Hmm, I just reread the original post and didn't read into it the same as you. I read that the OP was interested in learning more about how others were using satellite imaging, as well as the potential for using it in poorly charted areas. In fact, those were basically his words, and in no part did I read him say he wanted to use them solely as navigation charts. He didn't even say he wanted to use them for navigation at all. He seemed to mostly just want to understand what the topic was about and how others were using it. I think you projected your opinions about the subject onto his post.

Mark


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## mbianka (Sep 19, 2014)

I like to use GE for scouting out new anchorages or places i might want to gunkhole around with the dingy. I usually use it in conjunction with NOAA charts. Though in my land trip to see the total eclipse in South Carolina this summer I used GE to help scout out locations I could drive to to see the event.
I also use GE to note the various anchorage spots we stopped at in some of my travels like in the Maldives. For example if you click on a Goggle Earth photo in this blog post you cab see the Lat and Long of where we anchored the boat: THE BIANKA LOG BLOG: CAPT. MIKE IN THE MALDIVES: DAY TWO


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## Yorksailor (Oct 11, 2009)

What software produces google overlays with transparency? I tried to download one but my antivirus rejected the software.

Phil


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## Yawlman (Feb 19, 2017)

You can download every US nautical chart onto Google Earth and view it on GE. You can then toggle between GE view and chart view and actually see how close the charted objects are to real life.

Look at this video on Utube: "Viewing nautical charts on Google earth" It explains the whole process. I downloaded this 2 years ago, hopefully with the cut in NOAA funding this program has not been cut. It's pretty cool.


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## Arcb (Aug 13, 2016)

Yawlman said:


> You can download every US nautical chart onto Google Earth and view it on GE. You can then toggle between GE view and chart view and actually see how close the charted objects are to real life.
> 
> Look at this video on Utube: "Viewing nautical charts on Google earth" It explains the whole process. I downloaded this 2 years ago, hopefully with the cut in NOAA funding this program has not been cut. It's pretty cool.


I have been trying to get some where with this, it looks pretty cool. All the links I have tried have turned up to be out of date dead ends. I wonder if any one has current links or if this service has been discontinued.


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## Jammer Six (Apr 2, 2015)

Don't understand the advantage of Google Earth over proper navigation with a chart.


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## RegisteredUser (Aug 16, 2010)

Jammer Six said:


> Don't understand the advantage of Google Earth over proper navigation with a chart.


I didn't know you were not allowed to make use of both in a sanctuary city.
Something new...


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## colemj (Jul 10, 2003)

Travel to places where the charts are inaccurate or even no charts exist and you will see the benefit of google earth. Google earth is often more up to date with regards to shifting bars, changing entrances, etc than government produced charts.

Mark


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## RegisteredUser (Aug 16, 2010)

colemj said:


> Travel to places where the charts are inaccurate or even no charts exist and you will see the benefit of google earth. Google earth is often more up to date with regards to shifting bars, changing entrances, etc than government produced charts.
> 
> Mark


Different subject...

Some time in the past, you posted (another forum) about charts for the San Blas.
I've downloaded those but am have a tough/computer idiot time getting them moved to OpenCPN.
So far, the only charts I have on CPN are some of the US NOAA...which the program had ready as a prompt.

Charts of atolls: charts many times show no reef break when there is, as can be fairly well seen on GE. 
Similar with islands off the beaten track.
The GE picture/image is very helpful.
Anybody who has doubts should go play around on GE.


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## ecaldwel (Jul 11, 2004)

Arcb said:


> I have been trying to get some where with this, it looks pretty cool. All the links I have tried have turned up to be out of date dead ends. I wonder if any one has current links or if this service has been discontinued.


View the Youtube video here and click at bottom right to watch on the actual Youtube site 



Scroll down into the comments and you'll find people periodically provided a new link as the NOAA site changed. The comment from "J Wilson" just worked for me; downloaded the file, and updated GE. I'm now trying some of the features.


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## Jammer Six (Apr 2, 2015)

RegisteredUser said:


> I didn't know you were not allowed to make use of both in a sanctuary city.
> Something new...


I was going to work on parsing that, in English, but I needed to take a dump.


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## colemj (Jul 10, 2003)

RegisteredUser said:


> Different subject...
> 
> Some time in the past, you posted (another forum) about charts for the San Blas.
> I've downloaded those but am have a tough/computer idiot time getting them moved to OpenCPN.
> So far, the only charts I have on CPN are some of the US NOAA...which the program had ready as a prompt.


The San Blas charts should be in .kap format, which OCPN reads. Make sure you set OCPN chart preferences to the folder containing the charts, and then update/install them.

Mark


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## Tuna Driver (Sep 17, 2011)

Google Earth is great for planning passages. I rough out a route on the big screen, then transfer it approximately to my phone Navionics app. Then I zoom in close and 'fly" the route for safety. Easy to make small changes at that point. As was said before, the satellite imagery and GE photos of the most remote places are terrific to get an idea of what you will be seeing on approach. Pilot charts for out of the way places and stuff like Charlie's charts are getting harder to find these days. GE is also very handy to find shore resources. I have seen the nautical chart overlays on GE. Not as useful as flying the route on the phone or tablet for me. As for reef passes. There is nothing like timing the approach for good light. Once inside however, the previewed sat views are good to know where not to go or where the good snorkeling might be.


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## Jammer Six (Apr 2, 2015)

I wouldn't use Navionics if my ass was on fire and it had water.


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## oysterman23 (Jul 22, 2011)

I agree that Google Earth can be usefull as a navigational supplement but Ive been studying inlets along the south shore of Long Island and found the google sat photos (which are composite) are seldom fully up to date. There are days the images are composed of part near-time and part past days or month and the file numbers will not reflect that.
Also labels and location detail can be way off . This is true of most of the digital charts available from major software companies using processed Nooa data. On half the chartplotters in the local West Marine the channel I sailed in that day is depicted as a dry sand spit despite it having been navigable water for over 4 years. Local knowledge, my eyes, and TowboatUS have been the only reliable sources 
Your tax dollars are not being spent at the US Coast Survey unfortunately. And navigational disclaimers promise regular surprises from charting software

Sent from my SAMSUNG-SM-G930A using Tapatalk


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## colemj (Jul 10, 2003)

oysterman23 said:


> I agree that Google Earth can be usefull as a navigational supplement but Ive been studying inlets along the south shore of Long Island and found the google sat photos (which are composite) are seldom fully up to date. There are days the images are composed of part near-time and part past days or month and the file numbers will not reflect that.


GE isn't the only satellite service, and it can be productive to look at others, like Bing, for the best and most up to date pictures.

But no satellite or chart survey is going to keep up in real time with constantly shifting stuff.

Mark


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## Jammer Six (Apr 2, 2015)

That's why real sailors use NTMs.


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## capta (Jun 27, 2011)

Jammer Six said:


> Don't understand the advantage of Google Earth over proper navigation with a chart.


For somewhere like East Greenwich, RI, the docks are just inexact straight lines with no identification of the 4 or more individual shoreside facilities in a row there. Having an aerial photo really helps identifying the facility and dock you are to tie to.


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## RegisteredUser (Aug 16, 2010)

Extra tools like GE may not be deemed 'proper' but they can be very helpful.
Proper....is navigating safely.


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## colemj (Jul 10, 2003)

Jammer Six said:


> That's why real sailors use NTMs.


Not sure why listening to French rap music makes one a real sailor, but if it works for you, that's OK with me.

I prefer to navigate with the Dead Boys or maybe some Miles Davis. George Clinton around reefy areas, but Emmylou Harris in murky waters.

If I have to go French, it will be the Plastic Bertrand's.

Mark


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## Arcb (Aug 13, 2016)

I thought I would share a little project I have been working on. I have been experimenting with trying to find a quick path across this bay, as close to the rhumb line as possible. I haven't found a final solution yet, but this is one route I have been playing with. 

In the first thumb nail you can see the NOAA planning chart for the area, basically- there be dragons there (well, more like salt water crocodiles). 

The second thumbnail shows a route I have put together using google earth. 

The boat is an asymmetric multi hull, so standard draft is about 2 feet, however, the boat will sail (poorly) with the rudders kicked up in about 12 inches. It can be dragged in no water, which is less than any hydrographic survey vessel that I know of.


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## capta (Jun 27, 2011)

You can plan a good route, but all it would take is a couple of good fronts to significantly change some of the sand banks and shoals in the shallower waters of Florida Bay. Sounds like you are planning a fun trip. Kinda makes things interesting if you can stand up in much of the waters you'll be sailing in.


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## Arcb (Aug 13, 2016)

Good tip on the shifting sands, I guess there is no root material to hold things together. Still better to plan a route and be wrong then just to wing it I guess though.

And yes, we are really looking forward to the trip, counting the days. Weather has been rotten at home.


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## RegisteredUser (Aug 16, 2010)

Yeah, it does sound like a cool adventure.
I'd load plenty of anti-bug supplies.


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## boatpoker (Jul 21, 2008)

Had a bit of an argument with self named Master Mariner, RYA Yachmaster on Cruisers forum recently. He insisted there were no reefs on the east side of the Abaco cays because he couldn't see any on Google satellite.


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## hellsop (Jun 3, 2014)

boatpoker said:


> Had a bit of an argument with self named Master Mariner, RYA Yachmaster on Cruisers forum recently. He insisted there were no reefs on the east side of the Abaco cays because he couldn't see any on Google satellite.


Which kind of gets us to another issue: The imagery from the Abacos is anywhere from 1-4 years old, and much of the most recent stuff has a nice cloud deck in it. There's been 3-4 hurricanes through since most of the photographs were shot, so if rather than hoping to be able to pinpoint things like sandbars using Earth, it'll be more likely to lead you right onto something crunchy.


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## Arcb (Aug 13, 2016)

Interesting point about the age of the imagery, on the other hand how many decades old charts there are out there, some corrected in places some not, many surveys conducted by guys in rolling boats, probably not too many lead line surveys out there any more, but plenty of pretty basic acoustic surveys. 

I am not aware of any mapping technology that gives real time information. For real time information you need some kind of sensor. Depth sounder, RADAR, eyeballs, ears etc.

I guess the closest to real time information you can get for mapping is to use either drone photography or go out in your dink with a lead line or depth sounder and survey the bottom before following on a bigger boat (if you have a bigger boat).

I guess the nice thing about shoaling, is most of it comes in the form of sand and mud, neither of which is too threatening to a slow moving sailboat, although it can be an issue if you are moving or if there is surf or current pushing you on.


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## Arcb (Aug 13, 2016)

The London to Calais post reminded me I wanted to update this thread with my experience of doing this passage vs the google earth plotting I originally did. Its not London to Calais, but it has its own challenges.

Basically I plotted my routes for this passage using Google Earth because the charts I found lacked the granularity to estimate depths in relation to my draft (about 2 and a half feet sailing).

I attached two thumbnails, the first was my routes (2 maybes) that I plotted on Google Earth and verified with available charts, then dropped as routes to my handheld GPS. 

The second thumbnail is my actual Spot track which was what actually happened.

Noteworthy details include that I had no engine on board, so had to pick routes through the shallows that I could sail. This passage was done in the dark. Weather conditions were sustained winds around 15-17 with gusts into the mid 20s. There were approximately 3 frontal thunderstorms followed up with really strong winds from a cold front. Passage time was fast for the Bay, Flamingo to Key Largo in 7 hours. We wish we hadn't left Flamingo, but due to the NW winds, we couldn't turn back and we saw no safety advantage to anchoring in the prevailing conditions. The Thunderstorms were not fore cast, we listened to WX immediately before departure but they came up within an hour.

So here is how it played out. We left Flamingo following our GPS Track out through the marked channel. We were following the *Southerly route on our GE created track when we saw a bigger deeper draft boat head to a more northerly route. We checked our charts and saw value in his heading, and decided to just follow him as long as his route made sense. We followed him for about 90 minutes, before the second front hit and we blew past him at nearly double his boat speed on a broad reach (Cat vs mono drag race). 

Then we recalculated our route and decided to head back to our GE plotted route. In a flash of light, I spotted a stake in the mud with reflective tape on it. We quickly referenced our chart and realised it was a short cut not marked on the chart, which we took. It was hairy. Long narrow channel and we took a knock down half way through, which we some how recovered from without capsizing.

Once through the short cut, the plan was to reconnect with our route, which we did for a bit until we noticed to our south the main channel for the ICW. We made for the channel and just did red and green in between all the way to Key Largo. There are several missing Spot tracks for the final leg because one of us was napping on top of the Spot.

So, we didn't really use our planned route and instead, through a series of luck and observations we found a faster route, but we always had our GE route to fall back on as a reliable second option if needed.


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## MarkofSeaLife (Nov 7, 2010)

Great work


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## Jammer Six (Apr 2, 2015)

From this I draw the obvious conclusion: use Google Earth for navigation and you better be lucky.


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## MarkofSeaLife (Nov 7, 2010)

Jammer Six said:


> From this I draw the obvious conclusion: use Google Earth for navigation and you better be lucky.


All navigation requires some element of luck.

Some places in the Pacific Google Earth is to only map that's within 1/2 miles of accurate. Only a fool doesn't use it when sailing the islands of Tonga


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## Arcb (Aug 13, 2016)

Jammer Six said:


> you better be lucky.


Whats wrong with being lucky?

Florida has to be one of the most crowded places I have ever sailed. An endless line of cruising sailboats motoring from one crowded anchorage to the next. The Everglades Coast however, is empty. There is nobody there. I sailed the entire coast, camping on the beach beside my boat and could count on my fingers the number of other people I saw and it is easily one of the most beautiful coast lines I have ever sailed.

The down side is you have got to be willing to put in some effort and yes, take some risks. When you are taking risks, if some luck comes your way why not take it? People often take 3 days to cross Florida Bay in a sailboat, we got some lucky breaks and crossed in 7 hours.

The Everglades Coast is tricky, its poorly charted, unlit, there are no marinas for people to fill their sailboats up with gas and their are no Piggly Wigglys for people to stalk their freezers with frozen hot dogs. If it was easy, it would be as crowded as the rest of *South Florida.


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## Jammer Six (Apr 2, 2015)

I sail in Puget Sound and the San Juans. When someone counts on luck here, we run his ass over with a ferry.


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## Arcb (Aug 13, 2016)

Jammer Six said:


> I sail in Puget Sound and the San Juans. When someone counts on luck here, we run his ass over with a ferry.


I don't think you understand the context here. The area I am discussing isn't like Puget Sound (I went to college in Vancouver).

The area I am discussing is poorly charted. It's waist to chest deep water, marine grass lands and mangroves. There are no car ferries.


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## Jammer Six (Apr 2, 2015)

Arcb said:


> I don't think you understand the context here. The area I am discussing isn't like Puget Sound (I went to college in Vancouver).
> 
> The area I am discussing is poorly charted. It's waist to chest deep water, marine grass lands and mangroves. There are no car ferries.


Ah. Then I'm sure luck is your best bet. It's certainly a better bet than Google Earth. I think you're giving credit to Google Earth that belongs in lucks account.

You're wise to sail there rather than here. Neither will work here.


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