For the millions of project buffs (and professionals) who can’t spend their days watching the action at every site, the San Diego Water Authority has the solution: DamCam.
DamCam is a newly installed web cam system at the Water Authority’s San Vicente Dam that allows the public to watch the progress on the world’s largest roller-compacted concrete dam raise.
Photos: San Diego County Water Authority
|Before: In 1943, the city of San Diego built the 220-foot-tall San Vicente Dam to store up to 90,000 acre-feet of water. The raising will more than double the dam’s capacity.|
The Water Authority is raising the height of the 220-foot dam by 117 feet—the tallest dam raise in the United States and the tallest of its type in the world. The raised dam will store an additional 152,000 acre-feet of water, more than doubling the capacity of the reservoir, which is now 90,000 acre-feet.
Two cameras offer different views of the construction activities, enabling viewers to see weeks of dam raise work compressed into a brief time-lapse video.
Topside View offers a bird’s-eye perspective, while Downstream View provides a straight-on angle.
The high-resolution photos are updated every 30 minutes, providing a current snapshot of dam raise construction. The time-lapse sequences combine these photos, illustrating the construction process. (Think of a high-tech version of those old hand-drawn cartoon flip books.)
|October 2009: About two inches of concrete needed to be removed from the downstream face of the dam. Rails were installed to support hydrodemolition equipment, and workers excavated the hillsides around the dam to provide a solid foundation for the new concrete.|
The cameras were provided and installed by Work Zone Cam of New York.
The cameras wirelessly transmit the photos to a secure server at the Water Authority, where software is used to edit and compile them and prepare the time lapse, project manager Kelly Rodgers told the publication Government Technology.
The cameras were installed in December, at the mid-point of the project, which began in 2009 and is expected to be completed in 2013.
Aided by an online photographic tour that predates the cameras, however, the whole project can be viewed. (To view the photographic tour, visit http://www.sdcwa.org/san-vicente-dam-raise and click on Multimedia, then on Photographic Tour.)
Documenting the Record
“The value of this camera technology is that it helps the Water Authority document the historic record of this major construction project, while at the same time allowing members of the public to view its progress online,” Water Authority Board Chair Michael T. Hogan said in a statement.
Unlike live web streaming, the time-lapse approach using still images allows the Water Authority to review each image and select only those it wants to use.
|November 2009: To prepare the new dam foundation, crews excavated down to solid competent rock, then placed concrete into any crevices to level it out. Here, representatives of the Division of Safety of Dams monitor the work.|
The authority rejected the idea of streaming live video, because those involved with implementing the technology didn’t feel a live video stream would be secure enough, Rodgers told Government Technology.
Project Streaming Grows
But webcam and streaming video are becoming a larger part of project technology—and not just for conventional security purposes. BayBridge360, for example, has been capturing video of the San Francisco-Oakland Bay Bridge’s seismic safety project construction for years.
And with or without a public audience, the US Army Corps of Engineers, NASA, Balfour Beatty, New York City DOT, Skanska, Turner and other major agencies and contractors now use video to record projects under construction.
Video providers—like Work Zone Cam, EarthCam, OnsiteView.com, TrueLook and others—say the technology allows closer monitoring of projects by supervisors, taxpayers and clients; reduces travel expenses; documents critical events; and adds pizzazz to the facility owner’s web site.
‘See Their Tax Dollars at Work’
In San Diego, although the Water Authority is not streaming construction, it is providing another unusual look at the project, via a limited number of public tours. Guests will view the project site from the downstream, or dry side, of San Vicente Dam. Tour participants must be 18 years of age or older and must follow site safety and security procedures.
They must also act fast and stake out the authority’s web site: The first 10 tours are booked solid, and more have yet to be scheduled.
Rodgers said the dam construction had drawn tremendous public interest.
|March 2010: Crews used a road header, a drilling machine with a rotating head, to tunnel through 100 feet of concrete at the base of the dam.|
“This is a good tool for the public so they can see their dollars at work and the progress we’re making toward securing the region’s water supply,” she said.