By Maddyx Bride and Jenna Kessler, Staff Writers
// On Jan. 9, EBMUD (East Bay Municipal Utility District) officials presented an update of the plan to retrofit the Lafayette Reservoir Tower to the Lafayette City Council.
The Lafayette Reservoir is a significant historic site and popular recreation area in the Acalanes community. The reservoir consists of a dam that EBMUD constructed beginning in 1927.
“The initial construction, the dam base, began in 1927…The dam settled in September 1928 over a 10 day period. The night of the first cracks, Leo Coleman, engineer for EBMUD, had walked across the dam in darkness. [The cracks] caused him to tumble down the face of the dam …Work on the dam stopped for three years as it settled. It was finally completed in 1933, six years after the beginning of construction,” President of the Lafayette Historical Society Mary McCosker said.
The Lafayette Reservoir’s dam was originally built to control the water flow, prevent flooding, and provide water to Lafayette residents.
“The Lafayette Improvement Club (LIC), a group who functioned as a quasi-city government before Incorporation, was responsible for forming a water district that would bring Mokelumne River water to town…The dam at the end of town was designed to control flooding and provide water,” McCosker said.
The tower’s purpose is to act as an outlet to help control the water levels of the Lafayette Reservoir.
“The Lafayette Reservoir Tower functions as a spillway and outlet to control the Reservoir levels. It will allow water to safely drain from the Reservoir to Lafayette Creek if there are storms that result in very high-water levels or if there is another type of emergency,” EBMUD Engineering Manager of Engineering Services and EBMUD Community Affairs Representative Elizabeth Bialek and Kathryn Horn said.
The tower can be seen all over the town, from both the city’s Chamber’s logos, to Reservoir Run t-shirts and anniversary logos for the city.
“The Reservoir’s water tower has become a symbol for Lafayette over the years. Pictures and illustrations of the water tower now appear on the city’s website and on the Lafayette Chamber of Commerce logo. In fact, the winning logo selected in 2017 for the Lafayette 50th Anniversary of Incorporation was designed by Acalanes High School student Sofia Cruz and featured the water tower,” Lafayette City Council Member Wei-Tai Kwok said.
In 2005, EBMUD evaluated the Lafayette Reservoir and Dam. This evaluation found that the tower is at seismic risk.
“The Lafayette Reservoir dam is regulated by the Department of Water Resources Division of Safety the of Dams (DSOD) and has rated the Lafayette Dam as ‘Fair’ because of the seismic risk posed by the tower,” Bialek and Horn said.
If a powerful earthquake occurred, the tower would likely suffer damage that could affect its ability to fulfill its purpose.
“In the event of an earthquake, the tower is likely to sustain significant damage due to lack of steel reinforcement in the concrete. It does not meet modern seismic design standards and would bend and break and would not be able to function as an outlet and spillway,” Bialek and Horn said.
The tower’s new, seismically safe design will differ from the old one, specifically in height. “The new tower will be 40 feet shorter, which is appropriately sized for the height of the dam…The DSOD did not approve the base isolator concept and favored shortening as the most reliable approach,” Bialek and Horn said. “Tower shortening most reliably addresses the seismic concern and does not have long-term risks. It is the safest way to address the seismic hazard.”
Additionally, the new design includes a crane inside the tower, a new element for EBMUD outlet towers.
“Cranes are a standard element of outlet towers and allow EBMUD to maintain the tower. EBMUD and our consultants are working to design the crane to be collapsible and out of sight during typical conditions,” Bialek and Horn said.
Furthermore, in the new designs, EBMUD will remove the iconic ‘house’ on top of the tower because of its contributions to seismic instability.
“The ‘house’ at the top is strictly decorative and does not serve any operational purpose. It adds additional weight to the tower, which adds seismic risk. Lightweight replicas would not have an authentic look and would not capture the iconic feel of the existing tower, particularly over time [and exposure] to the elements,” Bialek and Horn said. “The new tower will have an aesthetic treatment, consistent with other EBMUD towers, with additional architectural detailing to provide a visually pleasing, durable, and functional tower.”
With Lafayette’s symbol looking significantly different, changes will have to be made to the city’s logos and other places.
“There’s no doubt that the tower image has established a strong brand identity for our city. If the retrofit changes the look and feel significantly, which is what is being proposed by EBMUD, then we would likely have to change our city’s brand iconography to move in another direction someday in the future,” Kwok said.
In an effort to inform the public of the retrofitting and allow for public input, EBMUD created a community outreach program for the project.
“In January 2023 EBMUD presented to the Lafayette City Council and hosted a Water Walk at the Lafayette Reservoir on January 28,” Bialek and Horn said. “Outreach efforts moving forward will include presentations to community groups such as the Lafayette Chamber of Commerce and the Lafayette Rotary, a write up for the Lafayette Historical Society, and a future Water Wednesday Webinar, social media outreach, signage at the reservoir and a project webpage.”
While this project does result in changing a memorable Lafayette symbol, the plan’s ultimate goal is for the community’s safety.
“I think the public understands that the retrofit is required for safety reasons. In a seismic event, the tower could be severely damaged. That being said, I think the public is fond of the old tower,” Kwok said.
Courtesy photos, Mary McCosker