Great Salt Lake's North Arm

April 19, 2024


PhotographerBrent Watson
Summary Author: Brent Watson

The Great Salt Lake in Utah is fed by hundreds of springs but their contribution to overall inflow is quite small. Shown above is one of these springs flowing into the north arm of the lake. I captured this photo while flying 1,000 feet (305 m) above the surface of the lake on September 26, 2003. Nature is a wonderful artist!

Back in 1959, Great Salt Lake was cut in half by a railroad causeway.  Since most of the inflow into this terminal lake is south of the obstruction, the salinity in the north arm is significantly higher than the southern part of the lake and is nearly saturated at 27 percent.  According to the Utah State Division of Wildlife Resources, the high salinity is ideal for Dunaliella salina, a pinkish-red alga. Two bacteria, Halobacterium and Halococcus, having purple-pinkish pigments, also thrive in the North Arm. These organisms are primarily responsible for coloring the waters of the Great Salt Lake's North Arm. It's estimated that between one million and one hundred million bacterium per milliliter are in this portion of the lake. 

Photo Details: Sony A6000 camera; ISO 100; 1/400 seconds exposure; at f9; 50mm focal length.

North Arm of Great Salt Lake, Utah Coordinates: 41.3975,-112.7939

Related Links:
Great Salt Lake Causeway
Algae and Foam on Great Salt Lake
Microbiology of the Great Salt Lake north arm