City Light Completes Cedar Falls Siren Testing

Mobile siren for Cedar Falls sound test

Seattle City Light staff tested various audible warning sirens near the Cedar Falls Masonry Dam on Wednesday, March 2. Staff picked four test areas and were stationed at nearly 10 sites for sound-level measurements.

The utility will be installing three new warning sirens later this year around the Cedar Falls Powerhouse, Rattlesnake Lake and the Masonry Dam.

The purpose of the siren system is to provide an emergency warning in the event of a dam failure. To learn more about the project, please visit

Testing to Start for New Warning System at Cedar Falls

The Masonry Dam at the Cedar Falls watershed.

Seattle City Light will begin testing March 2 for a safety warning system being installed at the Masonry Dam in the Cedar Falls watershed to warn people in the unlikely event of a dam failure.

Replacement of a safety siren at the Cedar Falls Powerhouse started in January. Additionally, pole-mounted safety sirens will be installed near Rattlesnake Lake and near the Masonry Dam. Siren testing will take place before and after the installations are complete.

“Safety is always a top priority for Seattle City Light,” Power Production Officer Mike Jones said.  “Installing this warning system will enhance safety for the community, visitors and our employees in the unlikely event of a dam failure.”

Seattle City Light selected a digital warning system made by Whelen. The system will deliver an emergency warning sound followed by a voice message alert.

“Whelen is proud to partner with Seattle City Light to upgrade and advance the emergency warning capabilities at their Cedar Falls facility,” Whelen District Manager Ed White said. “This digital system not only provides broad area coverage with warning tones, but also provides clear, easily understood voice commands appropriate to the emergency at hand.”

An example of a test siren like those that will be used to identify the best locations for installing sirens near the Masonry Dam.

The sirens will alert Seattle Public Utilities and Seattle City Light personnel working near the structures at Cedar Falls and people in the surrounding areas. Testing is being conducted to determine the best locations for the sirens to provide coverage for recreation areas, the Watershed Education Center and wilderness areas near the Masonry Dam.