GMCO map and "fish traps"
space inwaders 12/31/2008 - 13:20 Trip Tools Potomac
I recently got a copy of GMCO upper potomac map from dam 4 to great falls. I noticed 2 places marked on the map called "fish traps". Has anyone seen these? What are they?
Noticed that this map also labels the old rubble dam at seneca breaks as "dam 2". I had read that it was built by Native Americans before European settlers arrived. I figured dam no 2 was the washington aqueduct dam-great falls dam, and dam 1 must be little falls dam. (?)
Many interesting features are marked, like old mills, canals, roadbeds, and some named holes, boatramps, wading areas (most not near roads or parking??), rapids, riffles, dams, historic sites, and roadways.
I studied cartography in school mainly, so i notice some quirks w/ the GMCO map.
1. All maps should have a legend that defines all of the symbols used on the map- The GMCO has a legend, but does not define several of the symbols shown on the map. Most of these spots are labeled on the map, but some are not.
For example, dotted lines, dashed lines, dotted circles around a certain area, some without any label as to what is noted there. And some labels for example "gravel bar" but there's no symbol to show where it is- its a pretty wide river, especially if your wading or on shore. There are areas where 2 features are labeled with text, but only one has a symbol.
2. There's no depths anywhere, but the river level is variable. Still there are many extra deep holes i know of that are not marked in any way on the map.
3. Some rocks/boulders/piles are labeled on the map, but none of the ones i know of were marked.
I dont mean to take all of this space with complaints b/c the GMCO map is still a great map and a great resource to have at hand. I'm sure its designed for boaters as a tool for safer navigation more than a resource for fisherman.
I'm tempted to start working on my own "shore fisherman's map of the upper potomac" series.
Noticed that this map also labels the old rubble dam at seneca breaks as "dam 2". I had read that it was built by Native Americans before European settlers arrived. I figured dam no 2 was the washington aqueduct dam-great falls dam, and dam 1 must be little falls dam. (?)
Many interesting features are marked, like old mills, canals, roadbeds, and some named holes, boatramps, wading areas (most not near roads or parking??), rapids, riffles, dams, historic sites, and roadways.
I studied cartography in school mainly, so i notice some quirks w/ the GMCO map.
1. All maps should have a legend that defines all of the symbols used on the map- The GMCO has a legend, but does not define several of the symbols shown on the map. Most of these spots are labeled on the map, but some are not.
For example, dotted lines, dashed lines, dotted circles around a certain area, some without any label as to what is noted there. And some labels for example "gravel bar" but there's no symbol to show where it is- its a pretty wide river, especially if your wading or on shore. There are areas where 2 features are labeled with text, but only one has a symbol.
2. There's no depths anywhere, but the river level is variable. Still there are many extra deep holes i know of that are not marked in any way on the map.
3. Some rocks/boulders/piles are labeled on the map, but none of the ones i know of were marked.
I dont mean to take all of this space with complaints b/c the GMCO map is still a great map and a great resource to have at hand. I'm sure its designed for boaters as a tool for safer navigation more than a resource for fisherman.
I'm tempted to start working on my own "shore fisherman's map of the upper potomac" series.
