AQUA Maps - navigation tool

Some background, then will get to what made me excited last week in AQUA Maps.

Last fall when due to weather it looked like we were going to spend significant time in the ICW going from Chesapeake to FL I was looking for all the data I could get.

Went to a cruising seminar while laid over in Southport, NC, gentleman running it showed us the Corp of Engineers survey data. The CoE has survey boats which map the ICW channels and inlets. Frequency of survey varies by CoE district. I downloaded a library of pdf's from each state which when strung together showed the depth survey data for the ICW through NC, SC, GA, and FL. Probably a hundred pages I put into a binder. Downloaded charts showed the ICW, with channel markers, and a color display of depth. Shoaling spots were bright red, with deeper water shown as cooler colors (greens and blues).

You can tell whether center, red, or green offers the best path. Found it extremely useful.

Some states are very frequent, some not. I think it was NC that was surveying the entire route every year. SC was a two year cycle. FL was pretty current for the most part - most of the data was in the 1-3 year range.

An important caveat - those in FL know that shoaling info is sometimes only as current as the last tropical storm that came through. Inlets are particularly affected, long stretches of interior ICW are slower to change.

In my opinion this data should not be taken as an absolute indication of depth, rather a pattern of depth.

Bottom line, this data proved to be extremely useful but was a lot of work to compile and have at the helm to be able to use it.

Captain Rusty talks about when encountering shallow water "hunting" for better water. Unfortunately I don't have the experience in the routes or "intuitiveness" that he does. This tool has helped me know where I am likely to find deeper water in the channel.

A few years ago we could depend on shoaling notes in Active Captain - however it seems like AC is not being updated as much as it was in the past.

Fast forward to last week. Had a 20-30 mile run in the ICW to move the boat since the weather was poor outside. Was updating my chart databases on my iPad, and found a new option in AquaMaps. I have run this stretch of the ICW probably 7-8 times in the last 18 months. Did not expect any problems with the channel, but thought it was a good opportunity to try out this tool.

I still prefer BlueChart for trip planning - but since it does not receive updates I also use Aquamaps.

Ran onto a new option I had not seen before. On the settings page there is an option to include USACE surveys. When you choose the option, you have to re-download your charts. This option requires an additional overlay subscription which is $9.99 per year.

This option inserts the same survey data I had worked so hard for last fall directly into the AquaMap chart. Two views of the same area.

Without survey data:

With Survey data


This example was not the best, just something I grabbed to show the difference. In a lot of cases the the survey data does not always follow the depth contour lines on the charts. What I am looking for here is where to hunt for deeper water.

Granted the problem is the survey data is not as of "today", but in most cases it is newer data than the charts contain in contour lines.

Once again, just a tool. May or may not be useful for you, but I find it incredibly useful. The difference between 5ft and 7ft makes a huge difference to me.

I'm so used to deep water I get nervous when I see 10'. You must be stirring up the mud in that area.

Not the same contrasting colors, but Navionics clearly shows the depth concerns in this area...

I have Navionics, just don't seem to go there as much.

Do you know what the data source is? Thinking that Navionics has the crowd sourced depth data?

FootballFan said:

I have Navionics, just don't seem to go there as much.

Do you know what the data source is? Thinking that Navionics has the crowd sourced depth data?

Click to expand...

That is the "sonar charts" view in Navionics. Its more detailed and is from their own data and the recent data from users that have newer plotters and are allowing their sonar data to be uploaded to Navionics. Who knows how current it is though.

You can change the depth shading on Navionics to have your preferred minimum depth shown in white. The sonar charts view has other colour depth range options you can customize. Up here in Canada on Georgian Bay we have lots and lots of granite shoals with 100ft water right beside "run aground" water. And unlike sand shoaling, hitting a granite shoal will do some major damage every time. (But I guess it stays in the same place, unlike sand.) So I keep my plotter and iPAD version with the good water (I use 10ft to be safe) showing as white. Quick and easy to see.

Woody said:

I'm so used to deep water I get nervous when I see 10'. You must be stirring up the mud in that area.

Click to expand...

I get excited when I see 10’ of water.

I have no position on this, just sharing what I thought was a cool feature that I found. Not meant to endorse AquaMaps over Navionics.

In the session where I learned about the survey data, the guy doing the session discussed the crowd sourced data from Navionics.

"His" comments, not mine. He was not a fan. I don't know either way - but his point was you have no idea when the charts have crowd sourced data incorporated versus not. If you are riding over crowd sourced data, it is great, but you don't know when it starts or ends.

Crowd sourced data is anywhere the data is collected from. Survey data is just in the ICW and inlets.

Take it for what its worth. The example I posted probably was not the most representative of the value, I was looking for something that showed the color along the route I had taken. Note that the route I was on had no known problems. Was an easy trip without any data.

Going from Charleston to Hilton Head - I found the survey data extremely helpful. Maybe I could have gotten the same impact from Navionics.

I guess at the end of the day - my posting is more about an easy way to see survey data - not so much the App. Aquamaps is just the vehicle, not the content.

Here in NE Florida, where sand migrates a lot, I find the Navionics sonar charts to be useful. I even upload my own data to them. And yes, 10' of water is DEEP!

I think that along the ICW it's better to use aqua map (with usace overlay) and navionics (with sonar chart) (the most recent ipad allows to run both apps in split screen mode).
there are several important considerations:
the usace surveys indicate the depths to the MLL what happens if the track used for the sonarchart was recorded in a high tide peak?
after a dredging which of the two charts is first updated and available to users?