And there are more on the way.
Seattle police say the high-tech cameras are part of an expanding security project that also involves the Port of Seattle and the Coast Guard. The various agencies say the mission is to keep closer watch on the city's waterways, from Puget Sound into Elliott Bay.
But there's skepticism.
"I want to be able to trust at my age that what our government says is truth," said Karin Watson. "I've lived long enough to know that isn't always so."
Seattle police insist scanning the waters for illegal or sinister activity is the top priority, not monitoring what people are doing on Alki Avenue, Harbor Avenue and Beach Drive.
At least six cameras are mounted on city utility and light poles, right in the middle of residential neighborhoods.
Seattle police say once the cameras go operational, they'll have a backing on the side that faces peoples' homes and businesses, so the cameras can't be aimed that way, and instead focus all the attention out toward the water.
"As long as the police department is not using it to pick out individual people and spy on them, that's fine," said West Seattle resident Steve Epstein
But others wonder if certain freedoms are being compromised, and if this is the best way to increase protection and prevent harm from happening.
"Are we suspicious of surveillance in the U.S. in general?" wondered Ilyse Rathet. "Don't always believe that resources are invested for best use of the public."
Even before the cameras are turned on, police say the surveillance system will soon expand to the Seattle waterfront.
The money for the surveillance system is coming from a Homeland Security federal grant.