i have always wondered this. how do they survey lakes and create contour maps.
For the most part you won't find the old roads. They are all silted in after 70+ years. You may be able to find East Nimisila Rd by the campground under all the lilypads in 1 fow and the bridge on the west side of the lake.I found an old map of Nimisila Reservoir the other day. It showed the proposed dams and the old road that are now under the lake. Maybe one day I'll try and find these old roads!
Last year somebody posted a site with old maps. I salvaged this one from 1904.--TimFor the most part you won't find the old roads. They are all silted in after 70+ years. You may be able to find East Nimisila Rd by the campground under all the lilypads in 1 fow and the bridge on the west side of the lake.
The foundation from the old farmhouse by the large island can be seen but that is not exactly a great spot to fish. There is also a roadbed between the grass islands that goes to the old farmhouse from the south dam.
I met an old guy who grew up in the farmhouse during a Nimisila spring cleanup back in the '90s. I pulled my map out and he drew alot of the structures and roads. Most are gone or not findable or his memory was a little foggy after all those years.
It would be interesting to see your old map. Does it have a year on it?
When I was an undergrad we did a lake survey exercise as part of a fisheries class I took. We did about what you described here, except we didn't have a GPS I don't think. We had a map with the lake outline and then ran transects of the lake at a set speed while gathering depth data on the sonar. It was a plotter that printed the depth profile on paper so we could go back and manually add the depths in on the map once all the data was collected. That was back in 2001 though and with the sonar and GPS integrated now it's probably much easier.The Army Corps of Engineers was surveying the West Harbor channel over several days this summer. I assume it's going to be dredged within the next few years. They were in a small steel rowboat with a GPS and a laptop and a depth sounder The driver just kept going back and forth across the channel, moving about 10' (I'm guessing) after each pass. I'm assuming they had a data gathering software that took readings on GPS position and depth at a selected interval.
The father of a friends of mine was a civil engineer, and he told me the reason some straight roads suddenly have a set of S curves is, they didn't compensate for the difference between true north and magnetic north, so every once in a while they had to bump the road back over to where it was supposed to run.early 1900's were mainly done on the ground, i think some aerial work was done but gov. control, ill ask my old boss if any aerial was being done then, i do know that back then they used rods and chains for measuring.