ESCONDIDO — A new consulting firm is taking over construction management services for the city’s Lake Wohlford Dam Replacement Project.
The Escondido City Council unanimously approved hiring GEI Consultants, Inc. for $12.9 million to continue construction management services for replacing the 129-year-old dam.
Lake Wohlford Dam was first constructed with earth and rock in 1895 to a height of 76 feet. About 30 years later, the dam was raised to 100 feet using a slurry hydraulic fill process.
In 2007, during a routine seismic evaluation of the dam, the California Division of Safety of Dams determined that the hydraulic fill section could liquefy and fail in the event of a greater than 7.5-magnitude earthquake along the Elsinore Fault. In response, the city lowered the water level of Lake Wohlford to prevent surpassing the original dam height of 76 feet.
The proposed new dam, which would be constructed downstream of the existing dam, would restore the lake to pre-2007 levels.
The dam replacement project will be paid for by a California Proposition 1E Grant, a pending U.S. Environmental Protection Agency Water Infrastructure Finance and Innovation Act (“WIFIA”) loan, and the Water Enterprise Fund.
Angela Morrow, the city’s director of utilities, said the current construction estimate for the dam replacement project is approximately $88.5 million.
The dam construction presents a complex undertaking due to various factors, including limited accessibility and workspace owing to the rugged, hilly terrain; the presence of environmentally and culturally sensitive habitats; and operating a concrete batch plant and heavy earthwork equipment on-site.
The project will also have extended working hours during the placement of the roller-compacted concrete dam, which requires crews to install it continuously, 24/7.
In 2012, the city entered into a $2.5 million consulting agreement with RBF Consulting, Inc. to provide construction management services for the project. Early on, it was determined that Oakvale Road needed to be realigned to make room for the new dam.
Michael Baker International (MBI) acquired RBF during this time and began providing constructability reviews throughout the design phase, as well as construction management and inspection services for the road realignment.
In recent years, MBI has experienced a significant loss of staff members skilled in inspecting and managing dam construction projects. Coupled with the city’s anticipation of maxing out the original consulting agreement once Oakvale Road realignment is complete, staff requested proposals in search of a new consulting firm to take over construction management for the dam replacement.
Morrow said that although GEI Consultants, Inc. was chosen as the only firm that responded to the proposal request, the firm has extensive experience working with other roller-compacted concrete dams, including the Olivenhain and San Vicente dams.
“We reached out to several companies; some of them didn’t have work or weren’t local,” Morrow said. “A lot are busy enough right now that they won’t submit a proposal unless they have a good chance of winning it.”
The dam is expected to be completed in 2027.
