Walking downhill on the north side of Highway 61 from the Wunderbar, I espied a small red sign that said “Geodetic Survey Marker.” Geodetic is a word not often used. “What is Geodetic?” I said to the Internet, not knowing I would be plunged into history, science, government, real estate, GPS, artillery, and space.
Most of us have heard about surveys as they relate to boundaries of real properties. But we likely did not know that the first civilian science agency of the federal government was begun in 1807 under President Jefferson. They surveyed the young country’s coasts and created nautical charts of those coasts for maritime safety. In 1878 it was renamed the U.S. Coast and Geodetic Survey until 1970 when its functions were brought under the new National Aeronautics and Atmospheric Administration (NOAA). The renamed agency is known as the National Oceanic Survey and that part of its work on geodetic functions is called the National Geodetic Survey. So why do we care? It turns out, we care a lot on a daily basis.
Geodesy is the science of measuring and understanding the earth: its geometric shape, its gravity field, and its orientation in space, as well as the changes of these things over time. In practice, geodesy uses the principles of mathematics, astronomy and physics, and applies them within the capabilities of modern engineering and technology.
The National Geodetic Survey provides the framework for all positioning activities in the nation. The foundational elements are latitude, longitude, elevation, and shoreline information. Geodesy impacts many important activities—
1. Location and boundary determinations of all property.
2. Flood plain mapping and related flood insurance and limitations on buildings.
3. Dredging of rivers and harbors and construction projects of all kinds.
4. Physical sciences rely on accurate geospatial information for plate tectonics, hydrology, and Global Positioning Systems.
5. Military applications for artillery early on and missile systems now.
6. Satellites and space shots.
7. Weather and its forecasting.
So, what about the survey marker I saw? Today, a typical survey marker or monument is a brass, bronze, or aluminum disk or rod. Previously, prominent objects like water towers or church spires were also used as survey monuments. Hundreds of thousands of permanent survey markers can be found throughout the United States. They mark key points on the earth’s surface. A related marker is a geo marker, commonly used when exporting drawings or data to Google Earth. Geo markers require a precise latitude and longitude measurement.
Those of us who have lived in the Northwest Territories or the Louisiana Purchase lands note how often things are laid out in straight lines, natural objects permitting. Explorers like Jean Nicollet and General John Fremont mapped out lines along which white Americans could spread to the West. Some of the most famous American surveyors include George Washington, Benjamin Banneker, Meriwether Lewis and William Clark, Daniel Boone, Abraham Lincoln, and a surprise to most, Henry David Thoreau.
The north shore of Lake Superior is also part of the north coast of the United States. There are many geodetic markers along Highway 61. If you know how to manipulate a map available on the government website, you can probably find them all.
If this intrigues you, perhaps start with geodesy for the layman: www.ngs.noaa.gov/PUBS_LIB/Geodesy4Layman/toc.htm. I relied upon websites like that to write this piece.
The Minnesota Department of Transportation maintains websites that allow you to find the location of all geodetic markers in and next to Minnesota. Start here: www.dot.state.mn.us/maps/geodetic/.
Not all survey markers are equal. Some are unpublished. Some locate a site both vertically and horizontally. There appears to be one of those in each township along Highway 61. Some markers locate only vertically, some only horizontally. Our Grand Marais harbor has a slew of vertical only markers, and similar markers appear in the hills to the north. I found only one horizontal marker in the city, near the junction of Highway 61 and County Road 7. There is another one just beyond Chippewa City near the junction of Highway 61 and Bents Road.
Perhaps someone would like to organize a Geocaching or other GPS game around the Geodetic Survey Markers. If so, I’ll join in (as long as spry 78-year-old legs are accounted for). Such a gem would probably be better exercise for social distancing than golf! Happy hunting to those who like to hunt without bloodshed.
Steve Aldrich is a retired Hennepin County lawyer, mediator, and Judge, serving from 1997-2010. He and Myrna moved here in 2016. He likes to remember that he was a Minnesota Super Lawyer before being elected to the bench. Steve enjoys doing weddings, the one thing a retired judge can do without appointment by the Chief Justice.
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