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Red Phone, I’m calling about a big ‘X’ painted on Oak Ridge
Court. Just curious as to what it it’s for. Can you help?
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“Red Phone, I’m calling about a big ‘X’ painted on Oak Ridge Court. Just curious as to what it it’s for. Can you help?”
Red Phone: Dear X’d Out, Red Phone contacted several people to determine the origin of the X painted on the street, and learned it is the responsibility of the Santa Clara Valley Water District.
“We call them flight crosses, and they’re used for aerial mapping,” said Marty Grimes, SCVWD spokesman. “We used it earlier this year to create a detailed base map of Anderson Reservoir and its surroundings as part of the dam retrofit project.”
To get more details, Grimes contacted Dan Gilleland, supervising surveyor for the water district. He said there are 54 flight crosses set for the Anderson Reservoir mapping.
“Crosses are set on the ground in locations (throughout the area of mapping) that will ensure that there is minimal distortion in the photographs,” Gilleland wrote in an email to Red Phone. “Using our flight map, the photogrammetrist flies over the project at a pre-determined altitude, flight path, and air speed and takes photos at specified locations. In order to minimize the number of flight crosses for this project, we had the photogrammetrist use GPS units on his aircraft and a GPS unit on the ground, which when used together allowed him to precisely identify his location. All of this information combined allows the photogrammetrist to compile the desired map at the desired scale.”
By the way, construction on the Anderson Dam retrofit project is scheduled to begin in 2016 and finish two years later. The project is estimated to cost $110 million.
Good caller, hope that detailed information answers your question.
