Nav aid for the Columbia River

Chuckpacific · Posted: Thu Oct 07, 2021 2:31 pm Post subject: Nav aid for the Columbia River

You folks that do the Columbia....can you recommended a good nav aid? Navionics and GAIA aren't cutting it for me.

Chuck

TyBoo · Posted: Thu Oct 07, 2021 2:54 pm Post subject:

I just do the opposite of driving and try to stay in the ditch rather than between them.

I am still using 20 year old Garmin chips and so far it is able to identify everything I run into. I think when the chartplotters give out I will switch to using Aqua Map on my iPad. I already have the free app on the phone with the free chart for my end of the CR and it is pretty cool for the price although I haven't actually used it for navigation yet.

Good to hear from you! I hope you are doing well. I miss running into you and the Wineman. Do you still keep your boat at Cathlamet during the summer?

SnowTexan · Posted: Thu Oct 07, 2021 3:32 pm Post subject:

Which part of the Columbia? I go slow and often run outside to see what’s under the boat…. That’s upper reaches for ya. Navionics has been mediocre for me above Wells Dam. The main channel is marked (and its NOT where you expect it to be), but rocks and shallows are only moderately to poorly charted in my experience. Lower Columbia is probably charted pretty well but I cant speak from experience there.

rogerbum · Posted: Thu Oct 07, 2021 4:52 pm Post subject:

I use Navionics in combination with my Lowrance chart plotters all the time on the lower Columbia and haven't observed any differences of significance between them. I'd feel confident using Navionics on my phone down there if that's all I had for some reason. However, I'm set up to always have redundancy in chart plotters, radios etc so I can't imagine a circumstance where I only have my phone as a navigational option.

Where are you operating on the Columbia?

Chuckpacific · Posted: Thu Oct 07, 2021 5:25 pm Post subject:

Mike,

Good to hear from you. Yes, I'm still at Cathlamet from August - end of October. The main area I'm interested in is everything west of Longview. Navionics does a poor job on the Prairie, Clifton and South Channels which is an area I use a lot. I'm pretty familiar with the those places but would still like to have a map/chart overlay for backup/relative distances. Whatever I use will be displayed on my Ipad.
I was out Monday dodging the gill netters but what a beautifull day it turned out to be.

Chuck

Larry Brandt · Posted: Thu Oct 07, 2021 8:48 pm Post subject: The ship channel doesn't change.

The river changes all the time.

The bottom shifts majorly with every spring runoff, so you won't find any digital nav app that has detailed depth data. It takes constant surveys to generate the data that the map makes use to generate the charts. But the Columbia ship channel is continuously dredged and its location does not change. Therefore a 10 year old paper book will be just as informative as Navionics or other apps will be regarding the dredged channel. Out of that channel it's on you and your depth sounder.

(Says this skipper who just ran his sailboat aground on a shifting sand bottom. $$ aargh.)

journey on · Posted: Fri Oct 08, 2021 12:30 pm Post subject:

I notice that there are NOAA charts for the Columbia River, which I use on OpenCpn. These are vector charts and quite detailed. Aren't these good enough?

Both the NOAA charts and OpenCpn are free and they run on a PC (and Android for a small fee.) No Ipad.

I do agree that river bottoms change, but Longview is down near the entrance and I assume west of there it's pretty stable. Am I wrong?

Boris

PNW_Wesley · Posted: Sat Oct 09, 2021 11:00 am Post subject:

forrest · Posted: Sat Oct 09, 2021 11:45 am Post subject:

The Garmin Echomap allows you to update your Navionics charts of a particular area and record it to a chip. I use it out in the ocean on rock knobs for structure. The charts offshore were based on a US Navy survey in the seventies and are in meters. That is the reason for the odd footage numbers on the contour lines. I think the charts were done to identify Soviet submarine hiding spots and not accurate enough for fishing. The Navy charts can be off a quarter to half a mile.