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.

Cedar Falls penstocks get new coat of paint in high-wire act

You think painting your house is a challenge? Try removing lead paint from an 11-foot-wide pipe, pressurized to 128 pounds per square inch, while hanging a hundred feet over the city’s clean drinking water supply.

That has been the work situation for contractors working to repaint the trestles and pipes that carry water from the Masonry Dam to the Cedar Falls powerhouse, in the protected watershed of the Cedar River.

Since last summer, workers have toiled to remove the lead paint applied to those structures in 1978, and to seal and repaint three metal bridges that carry the pipes across the Cedar River ravine. The new, environmentally sound paints and sealants will help to protect the quality of the water in the river below.

Workers started this summer on the smallest of the three crossings. The project required full scaffolding and a plastic pressurized enclosure to prevent the lead paint dust and chips from falling in the river during removal.

“We opted to start with the smaller truss bridges to remove the lead from over the river, and follow with the much larger trestle which will take most of a year to do on its own,” said Tom Pulford, project manager.

 The work is being carried out by the central California firm Certified Coating Company Inc, backed by their scaffolding and containment sub-contractor Performance Contracting Inc., from Kent.

The first part of the job was planned for completion in late November last year, but workers found that the penstocks were leaking from rivet holes and other connections in the pipe. As a result, City Light had to drain the penstock and apply sealing epoxy to the leaking areas.

After an extensive effort to dry the surface for the replacement coating, the first bridge will be finish painted in the next two weeks, using environmentally sound primer and final coating.

The first bridge is approximately 10 percent of the total project. Workers will next tackle a 115-foot-tall and 900-foot-long trestle bridge. Out of the forest setting will rise a 10-storey-tall white containment structure, wrapped around five towers and joined at the top. The work should take most of 2015 to finish.

The entire project should be complete by 2016, adding service life to the 90-year-old structures. It also will help protect the environment and the quality of Seattle’s drinking water, already among the best in the country. Taking care like this to operate in an environmentally responsible manner is just one more way City Light demonstrates why it is the nation’s greenest utility.