The level of Great Salt Lake's south arm declined 0.2 of a foot during the second half of hot, dry August to 4,207.4 feet above sea level, a U.S. Geological Survey measurement showed Thursday.

Brine salinity was 9.1 percent compared with 5 percent during the mid-1980s and 12 to 25 percent before extra-wet seasons of the early 1980s.The lake level is down 2.15 feet since its seasonal peak of 4,209.55 feet Feb. 10, said Kidd Waddell, USGS Water Resources Division hydrologist. It is 2.7 feet lower than a year ago and a surprising 4.45 feet lower than its recorded historic high of 4,211.85 feet March 30, 1987.

USGS operates an official level gauge at Saltair Beach's boat harbor in cooperation with the Utah Division of Water Rights.

Lake water temperature is 24.5 degrees Celsius (76.1 degrees Fahrenheit).