New Navionics Card Question

[KCLOST]

I just purchased my first ever Navionics Card - South Region, since it was on sale at BPS.. I really wanted one, as it covers a few good lakes around my area the Lakemaster does not. However, after logging into Navionics and downloading the data to the new card I was disappointed in the contour detail that were on many if not all of my area lakes. For instance, on my home lake it doesn't even show contour lines any shallower than about 6 ft anywhere on the lake. This in turn leaves many cuts and even creek arms completely void of any contours at all. Is this normal for Navionics, or do I possibly have something set-up wrong on my Helix unit?
Thank you for any help.
Here is a shot to show you what I mean...

[KCLOST]

I know this isn't a Garmin unit question, but I figured it would be most appropriate to ask in this forum since Navionics is a Garmin company??

[LWINCHESTER2]

It just looks like Navionics only mapped the main channels. Probably not anything wrong with your unit. If the water level fluctuates that much, they may have mapped it a low water levels. Just guessing - I'm not in the know about Navionics.

[Wayne P.]

Did you check both map layers?
Nautical Chart
Sonar Chart

Also it looks like there was no water or very shallow (no boat access) in the blank areas in that part of the lake when it was surveyed. You can compare your map to the same map on the Navionics website's Chart Viewer, the site map is current as of today.

[KCLOST]

Also it looks like there was no water or very shallow (no boat access) in the blank areas in that part of the lake when it was surveyed. You can compare your map to the same map on the Navionics website's Chart Viewer, the site map is current as of today.

The blank areas you see are very accessible, and very large areas as well with water as deep as 12-15ft deep in the middle of the creeks, as I know this lake well. The contours really do not match up with reality at all on this image.
Also it does match up with what you see on the Chart Viewer.
I guess it is just a poor quality map?

I will check the Nautical/Sonar deal...

[Wayne P.]

IF the shallow areas were accessible at the time of the survey, there would be contours there. It may have been that drought thing.
Even the Sonar Chart map layer contour lines don't go all the way into the coves and those lines are created from unit user sonar logs.

[KCLOST]

IF the shallow areas were accessible at the time of the survey, there would be contours there. It may have been that drought thing.

I understand your point, but there is no way there was a drought that brought this lake down to make any of these cuts/creeks inaccessible... The creek in the middle left hand part of the screen that ends at the road is approx. 3/4 of a mile long and has 20 ft of water at the mouth and even 5-6 ft of water at the rip-rap bordering the road...
But the lack of contours is not unique to just this lake. This appears to be the case on most all of my area lakes looking at the Navionics card... They do not appear to show contours in less than 5-6ft of water and just flat miss entire areas all together that have deeper water than that.