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You're invited to find this one

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I've been deployed overseas for a while, and after suffering a little from survey mark withdrawal, I was pleased to find this mark at N35° 27.226 E44° 20.607.




Note the stamping name, and also note it was set by the Expeditionary Civil Engineer Squadron (ECES). I'll have to talk to that unit to see if there are more marks and any other data associated with it/them.


Maybe I'll create a waymark but either way I thought you'd all like to see this. And here's a 'shout out' to my pal TeamFawlty back home -- sorry I haven't kept you updated on things but I hope all's well and that you're having fun BM hunting. Would like to team up with you and find that little copper bolt along the canal back home some time. Stay safe.

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Very excellent find!


A U.S. Power Squadrons unit published an illustrated article on Corps of Engineers benchmarks found in Tikrit.


I wonder if there are pre-2003 benchmarks in Iraq, and what they look like.


I wouldn't expect them in the desert, but it wouldn't surprise me if there were some in the cities, perhaps as a legacy of the British mandate after WWI. Trig Points on the Tigris, anyone?


# # #


After writing that I found this article in The American Surveyor (Nov. 2005) that describes establishment of a modern geospatial reference system in Iraq. The authors write —


[T]he 175th survey section discovered that Iraq did not have an established spatial reference system. Further research uncovered the fact that data from previous British (circa 1917) and Polish (circa 1975) control surveys was available for some parts of the country; however the historic surveys were performed to satisfy separate project requirements, and the segregated survey networks were not joined to form a continuous network that would benefit the nation at large.


A bit more detail comes in another article published in the American Congress on Surveying & Mapping's ACSM Bulletin (Dec. 2007). Wisam Al Hassani writes —


Geodetic and mapping work in Iraq goes back at least a century. The Surveying and Mapping Directorate where I work was established by the British after they occupied Iraq in 1921. They also built Iraq’s first-order horizontal and vertical networks and produced the first national map for Iraq. We still use that map to determine property ownership. The vertical datum, which we call the British Vertical System, it (GTS), has its starting point in Mean Sea Level (MSL) on the Persian Gulf; benchmarks were established by conventional leveling. Older irrigation projects are based on that datum.


In 1974, intent on modernizing surveying and mapping activities in Iraq, the government signed a contract with a Polish company. The objective was to establish new horizontal and vertical networks in Iraq and redraw the country’s map using aerial photogrammetry.


Under the contract, Iraqi geodesists triangulated 2600 horizontal points between 1974 and 1979. The points were distributed in 15-km intervals, and they were determined by astronomic observation, triangulation, trilateration, and least squares adjustment.


At that time, this network was one of the best in the region. There is little information about it in literature, but we know that its reference frame was the Clarke 1880 spheroid, because it had the best non-geocentric fit for Iraq.


For the vertical network, also known as the National Elevation Network, 1600 first-order vertical benchmarks were levelled from the MSL measured in Fao city on the Persian Gulf. Gravimetric measurements were also taken using conventional geodetic precise leveling to distribute the network along the main roads with a spacing of about 5 km. Information about the calculation of this national elevation datum is incomplete, and because of this, some of our irrigation projects still use the British vertical datum.




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