I'm noticing a lot of the contour maps from MN DNR on the lakes I've looked at come from the 1970's era. Curious to your thoughts on the general accuracy on these maps (not sure of their procedure used to make the maps). Do they not show certain humps / reefs in the lakes that could be productive? What is your experience?

Yes, they are guidelines, at best. They do give a good start, like maximum depth, locations of potential structure, etc. but they are pretty sketchy and usually only have 10-ft contours. Finding maps done as recently as the 1970s? Many are from much earlier and were done with weights and string. Using a Garmin or LakeMaster or Navionics chip or app would be a great improvement.

When those maps were made,GPS etc. was not available and many fish locators were just coming in fashion.
It is amazing they are accurate as they are,but they will miss small bars and points.

If it's like Illinois you can't expect anything to be accurate.

And some of the small lakes they are reversed..best to have a depth finder

quote schweady: "Yes, they are guidelines, at best. They do give a good start, like maximum depth, locations of potential structure, etc. but they are pretty sketchy and usually only have 10-ft contours. Finding maps done as recently as the 1970s? Many are from much earlier and were done with weights and string. Using a Garmin or LakeMaster or Navionics chip or app would be a great improvement.
"

The maps I'm looking at for this year, Fairy, Gun, Thunder, Moosecamp etc. show a date around 1970. Some of the area I went to last year were 30's or 40's era. Are there better lake maps (more accurate / current) to be had through another source? I do have a depth finder and Navionics app on my phone, but would like to get as much knowledge about the lakes as possible before hand.

You can scroll over to those lakes on your Navionics app on your phone from your armchair, can't you?

If not, visit Navionics Webapp on your computer. (Trouble is, it appears that Navionics is drawing all of your targeted lakes in basic 10 ft contours, perhaps sourced from and identical to the DNR maps you've found. Compare this to the 1-ft contour lines done for Burntside or the 5-ft lines done on Oyster, for example.)

Some of your big lakes in the state in the last decade with modern technology a private company did like 1 foot increment.
The MN DNR has many lakes with 5 foot increment out to a certain depth.
In reality for much of their needs the DNR doesn't need a map in 1 foot increments even tho it is really nice and may show a few more navigation hazards.

If you can manage to keep your canoe locked into a 20ft hump in the middle of winchell and able to use 1ft contours you need too tell me your secret. I've gone to many lakes with good electronics, navionics, etc. They all help, a little ( my wife will stress the little). But I've caught more fish just paddling around or casting the shore than finding submerged structure and anchoring. The latter is a lot more relaxing. A hand held depth finder is cheap. Find the fish first, note the depth and surrounding area(where the shore is), then just fish that depth and area. The dnr maps are useful for type of weed structure as well as bottom structure and I find the 1930 maps to be very accurate. I have a portable underwater camera, which is a complete waste of weight in the summer. The maps are a good starting point. Good luck!

quote schweady: "You can scroll over to those lakes on your Navionics app on your phone from your armchair, can't you?


If not, visit Navionics Webapp on your computer. (Trouble is, it appears that Navionics is drawing all of your targeted lakes in basic 10 ft contours, perhaps sourced from and identical to the DNR maps you've found. Compare this to the 1-ft contour lines done for Burntside or the 5-ft lines done on Oyster, for example.)
"

Thanks for the Webapp link. Yes, I've always thought the phone app used maps from the DNR. The app is great for general GPS locating and marking points that I feel are worthy of return fishing.

The DNR maps are a decent starting point, but they were not surveying with enough point density to catch many of the humps that hold fish. Try looking at aerial photos from the different sources (Google maps, Bing), and you can often see some of the shallower humps, which is also some fun armchair research.