But because the dam was built at an elevation of 7,330 feet, the 92-year-old structure is subject to the stresses of freezing and thawing during the winter.
National Dam Safety Awareness Day
May 31 is National Dam Safety Awareness Day, which is commemorated to remember lessons learned from previous dam failures. Learn more about dam safety here.
In 2014, SCE began a project to mitigate erosion and leakage at the most critical arches by installing a geomembrane liner on the dam. The last of the work will resume in September.
“We routinely conduct maintenance and repairs on our dams to ensure public safety,” said Nicolas von Gersdorff, SCE’s chief dam safety engineer. “The geomembrane liner provides waterproofing and will reduce freeze-thaw damage to the concrete.”
Made of PVC (polyvinyl chloride), the liner molds to the arches like white plastic wrap, sealing them from the water. A similar liner was installed at Shaver Lake several years ago.
The liner is a relatively new development in protecting dams. In the past, various coatings or spongy concrete was used to fill in cracks or chips caused by erosion to the dam, but they weren’t as effective as the new liner material.
Installing the liner is a multi-stage process. First, crews grind down the concrete face so they have an even surface to work on. They then install a layer made up of a felt-like material. They cover that with the geomembrane which first must be heated so it will create a secure seal as it cools.
Crews have faced several challenges installing the liner. Under the dam’s permits, the water level must be maintained at 21,000 acre-feet until Sept. 1 so the lake can be used for summer recreation. The liner project requires the lake to be drained to 1,000 acre-feet.
In addition, all the liner work must be completed by Oct. 31 before winter sets in. That leaves a two-month window to do the installation.
The concrete arches, which soar as high as 15 stories, also required a unique approach. Contractor Carpi USA devised an innovative three-part scaffold so workers could reach the entire curved surface of each arch.
The last of the liner work will be completed by the end of October. The liner is expected to last 50 years.
"Every customer counts," says Terry Ohanian, Southern California Edison’s incident commander for the first Public Safety Power Shutoff event this year. Only three SCE customers on one section of a circuit ...
Life might indeed be cool by the pool, but it’s even better when it’s safe in and around the water. That safety begins with an annual electrical inspection of your pool, hot tub or spa and all their working parts to ensure that life-saving devices...
It started on a Saturday evening in the remote mountain community of Wrightwood, a small brush fire that grew to 35 acres by Sunday morning, June 12. Firefighters thought they had a good handle on the blaze. ...
Mary Finn remembers January 2021 all too well. Southern California Edison had activated its Community and Climate Equity advisor to Simi Valley, where winds exceeding 70 mph had prompted the company to initiate ...
This Site is owned by Edison International. Unless otherwise indicated, all of the content featured or displayed on this Site, including but not limited to, text, graphics, data, photographic images, moving images, sound, illustrations, computer code, trade marks and logos and the selection and arrangement thereof (referred to in this section as the "Content") is owned by Edison International, its licensors or its third-party image partners and all rights in relation to the Content are reserved. All Content is protected by copyright, trade dress, moral rights, trade mark rights and other laws relating to the protection of intellectual property. You may use the Content for your personal, or news-related, non-commercial use, but you may not otherwise reproduce, modify or in any way commercially exploit the Content.