Newman Lake Wa is located 21 miles East of Downtown Spokane Washington and just 5 miles North of Interstate 90. Nine miles of shoreline covering 1,400 acres the lake area is wooded with pines and fir trees making Newman Lake an ideal area for family homes both summer and year-round. Newman Lake is a small community in Spokane County, Washington, United States. Newman Lake, which took its name from early settler William Newman. Newman Lake has a post office with ZIP code 99025. It is also home to Ellerport Airport, a private-use airport. In the summer of 2014, freshwater jellyfish inhabited the lake.