The latest news in surveying and mapping.

An NGS expedition revealed the source of the Amazon River.

Mapping the Source

Some people believe the Amazon River is the world’s longest river. Although the Amazon is not the longest, it does hold the most water—more than even the Nile, the world’s (disputed) longest river (its volume is 60 times greater). And now we know the precise ultimate source of this voluminous river, thanks to a daring expedition team and advanced navigation technology.

By foot, Jeep, bicycle and horseback, the team, while on a National Geographic Society expedition, explored the area in the mountains in weather well below zero. They used advanced GPS equipment, specifically, Trimble’s Pathfinder Pro XRS, and GeoExplorer 2 and 3, to make measurements that identified the exact source of the river as a stream beginning on Nevado Mismi, an 18,363-foot-high mountain in southern Peru. Trimble’s Pathfinder Pro XRS (Trimble, Sunnyvale, Calif.) is a GPS receiver that provides real-time submeter accuracy, satellite differential and beacon capabilities; Trimble’s GeoExplorer 2 and GeoExplorer 3 are hand-held data collection and data maintenance systems. The equipment was considered accurate to within 1 to 5 meters.

Geographer Andrew Johnston walks along Lake McIntyre on Nevado Mismi with his GPS equipment.
Andrew Johnston, of the Smithsonian Institution’s National Air and Space Museum in Washington, directed the GPS work. He stated that “the ‘source’ of the Amazon can be defined as the most distant point in the drainage basin from which surface water runs year-round, or the furthest point from which water could possibly flow to the Atlantic.” He reported that the GPS data was gathered daily from a base station at 15,500 feet near the nexus of several tributaries of the Apurimac River, the river considered the most distant from the Amazon’s mouth. GPS equipment used by mobile teams mapped the area’s drainage features and the path of the Continental Divide, which defines the boundary of the Amazon River drainage basin.

The 22-person team, from countries including the United States, Poland, Peru, Canada and Spain, made the expedition in July 2000. The expedition was bolstered by the preliminary data and organized field logistics gathered in four survey trips from 1998 and 1999.

GPS data was gathered daily from a base station near the Apurimac River to pinpoint the Amazon’s source.
The Amazon springs from the Andes’ high glacial regions, and the riddle about its source has inspired speculation for centuries. Jesuit Cristoval de Acuna documented his theory in 1641, on the Amazon’s source to the king of Spain. Now, over 350 years later, the source is confirmed. Andrew Pietowski, the team’s leader, summarized the great feat: “The trip’s result is a highly reliable map of the Amazon’s headwaters and an accurate determination of the river’s source.”

A Tree to Call Our Own

Oak, Maple, Pine, Spruce, Birch, Beechwood, Dogwood, Elm, Ginkgo and Magnolia are only a few of the trees populating this country. Most surveyors could name more, depending on geographic location, or at least recognize them by sight. Surveying puts surveyors in touch with the elements and the earth all the time. It’s part of their job. That is why the campaign sponsored by the National Arbor Day Foundation to select America’s National Tree is relevant to surveyors. Surveyors spend so much time around trees that it should give them a little expertise (or opinion at least) in selecting a national symbol. Americans can choose from a selection of 21 tree candidates or suggest a tree of their choice. This list also includes state trees and educational information. All votes must be in by April 26. The National Arbor Day Foundation will announce the selected tree of the American people on National Arbor Day, April 27, 2001. Votes can be registered online at or by mail to: The National Arbor Day Foundation, Nebraska City, NE 68410.

Acquisitions Continue in Industry

Leica Acquires Laser Alignment

Leica Geosystems, Heerbrugg, Switzerland, aquired Laser Alignment, Grand Rapids, Mich. The transaction allowed Leica to establish a leading position in high-precision 3D guidance and automated machine control systems for use on construction sites, in mining applications and in the agricultural market. Leica Geosystems Machine-Control and Guidance business area will be headed by Kurt Schibli, an employee of Leica since 1985, and will be concentrated in Grand Rapids.

Bentley and Intergraph Complete Acquisition

Bentley Systems Inc., Exton, Pa., acquired Intergraph Corporation, Huntsville, Ala. Under local agreement, many worldwide Intergraph units will continue to offer civil, plotting and raster product lines and other Bentley products. During 2001, Intergraph service contracts will be transitioned to the Bentley SELECT technology and services subscription program.

The acquired Intergraph product lines include the plotserver products, which support online digital plotset dissemination and content-based queries; the raster-conversion products, which facilitate the creation of editable digital representations of hard copy engineering drawings; and civil products, which provide the engineering foundation for virtually all of the transportation infrastructure in North America.

According to Bentley CEO Greg Bentley, “The consolidation of these leading Intergraph products within Bentley’s portfolio brings Bentley worldwide leadership positions in two E/C/O segments with tremendous growth opportunities, civil engineering and plotset content management.” Acquires SDC Survey Software, an Applications Gateway portal, Charleston, W. Va., signed an agreement with Dewberry & David LLC and Dewberry Technologies Incorporated, Fairfax, Va., to acquire the rights to market, sell and distribute SDC Survey Software. The acquisition includes both SDC Mapping and SDC Construction products. The software’s creator, Robert Kan, joined’s software division in January of 2001.