Utah Lake, freshwater lake in Utah county, north-central Utah, U.S. It covers 150 square miles (390 square km) and is 23 miles (37 km) long. Utah Lake drains through the Jordan River into Great Salt Lake to the northwest and is a remnant of prehistoric Lake Bonneville. It is the site of Utah Lake State Park and of waterfowl and bird preserves; at the turn of the 21st century, more than a quarter of a million people made their homes near its shores.