Col. Joshua Bost, right, incoming U.S. Army Corps of Engineers Los Angeles District commander, receives the USACE colors from Brig. Gen. John Lloyd, U.S. Army Corps of Engineers South Pacific Division commander and division engineer July 31 in the Fort MacArthur Community Center in San Pedro, California. The passing of the colors in a military change of command ceremony symbolizes the transfer of authority, responsibility and the unit’s enduring history from an outgoing commander to an incoming commander. USACE PHOTO BY SHAWN DAVIS
Command Succession: Col. Joshua Bost Assumes Command of USACE Los Angeles District
Command Transfer Ceremony: Col. Joshua Bost officially assumed command of the USACE Los Angeles District from Col. Andrew Baker during a ceremony at Fort MacArthur on July 31, 2026.
65th District Commander: Col. Bost takes command of a 700-person workforce managing a $750M annual program across 226,000 square miles in California, Arizona, Nevada, and Utah.
Historic Operational Location: Ceremony held overlooking the 1912 San Pedro Breakwater, the foundational civil works structure that created the modern Port of Los Angeles.
Record-Breaking Portfolio: Under outgoing commander Col. Baker, the district executed over $2 billion in a single fiscal year, including Task Force Phoenix emergency debris removal.
Critical Infrastructure Oversight: Manages 17 commercial/recreational harbors (handling 40% of U.S. trade volume) and major dam modifications at Prado and Whittier Narrows.
Editor’s Note: The following is from the USACE Los Angeles District, curated by America’s Engineers for civilian, commercial contractor, and industry visibility. The original report can be found at the U.S. Army Corps of Engineers Los Angeles District news repository.
The U.S. Army Corps of Engineers Los Angeles District conducted a change of command ceremony July 31 overlooking the San Pedro Breakwater, the maritime project that launched the district’s presence in the region in 1898.
Attendees of the July 31 U.S. Army Corps of Engineers Los Angeles District change of command ceremony await the start of the ceremony while Soldiers of the 300th Army Band play in the Fort MacArthur Community Center at San Pedro, California. Col. Andrew Baker transferred command to Col. Joshua Bost during the ceremony, ending his tenure as the 64th U.S. Army Corps of Engineers Los Angeles District commander as Bost begins as the 65th. USACE PHOTO BY SHAWN DAVIS
During the traditional passing of the organizational colors at Fort MacArthur, Col. Andrew Baker relinquished command to Col. Joshua Bost. Bost becomes the 65th commander of a district that oversees a workforce of about 700 personnel and a $750-million annual program across 226,000 square miles in Southern California, Arizona, Nevada and Utah.
The ceremony’s location, one mile from the breakwater, highlighted the district’s civil works and military construction origins. Completed in 1912 by Army engineers, the two-mile-long rock wall created the modern Port of Los Angeles.
Col. Andrew Baker, outgoing commander of the U.S. Army Corps of Engineers Los Angeles District, delivers remarks during a change of command ceremony July 31 at Fort MacArthur in San Pedro, California. Baker relinquished command to Col. Joshua Bost after leading the district since July 2023. USACE PHOTO BY STEPHEN BAACK
The event recognized the tenure of Baker, who commanded the district since July 2023. Brig. Gen. John Lloyd, South Pacific Division commander, presided over the ceremony and detailed the complex workload and historic response missions the district managed under Baker’s leadership. These included the region’s first tropical storm in more than 80 years and a major wildfire response.
The wildfires tested the district’s emergency operations capabilities. In response to the damage, USACE established Task Force Phoenix.
“The Corps of Engineers would go on to execute the largest debris removal effort in our organization’s history, completing the work six months early,” Lloyd said, adding that the disaster directly impacted district employees, retirees and their families.
Work pauses Aug. 26, 2025, shortly before a milestone event marking the start of debris removal for the last opt-in private property in the Pacific Palisades fire recovery area in Los Angeles. USACE photo by Stephen Baack.
During his remarks, Baker credited the civilian and military workforce for managing those emergencies while simultaneously executing the district’s regular operations.
“I’m awestruck by how we faced head on and overcame so many challenges, and by how we continue to grow and mature, to become even better,” Baker said. “The Los Angeles District has an amazing, amazing reputation throughout the Corps, earned over 125 years, delivering infrastructure critical to our economy, resiliency and defense on a grand scale.
“We answered the bell every single time with flying colors, coming through in spades,” Baker added regarding the district’s response to the region’s emergencies.
Col. Joshua Bost, left, incoming commander of the U.S. Army Corps of Engineers Los Angeles District, and Col. Andrew Baker, outgoing commander, stand at attention during a change of command ceremony July 31 at Fort MacArthur in San Pedro, California. The ceremony marked the transfer of authority of the LA District’s four-state mission from Baker to Bost. USACE PHOTO BY STEPHEN BAACK
Baker also highlighted the dynamic interagency landscape the district navigated while executing its programs, particularly given the region’s high visibility.
“The permits we’ve issued, the drum beat of delivering communication with our partners — local, state and national — the town halls that we’ve led — some of them contentious, some of them are great — but always an adventure,” said Baker, pointing out that the Chief of Engineers, Lt. Gen. William “Butch” Graham, visited the district five times during his command.
Baker also highlighted the district’s fiscal discipline, noting that the team was “successfully balancing our budget in one of the most expensive places to work in the U.S., working a razor’s edge on funding and staffing, to keep our aging infrastructure in great shape.”
Col. Joshua Bost, left, incoming commander of the U.S. Army Corps of Engineers Los Angeles District, shakes hands with Brig. Gen. John Lloyd, South Pacific Division commander, after delivering remarks during a change of command ceremony July 31 at Fort MacArthur in San Pedro, California. Lloyd served as the presiding officer for the transition ceremony. USACE PHOTO BY STEPHEN BAACK
During Baker’s three years in command, the district executed the largest program in its history, surpassing $2 billion last year alone. The district serves the largest percentage of the American population within its boundaries of any USACE district in the nation.
That workload included completing strategically vital projects for military customers at Fort Irwin, Nellis Air Force Base and Vandenberg Space Force Base, alongside significant progress on Department of Veterans Affairs projects in Long Beach and San Diego.
Simultaneously, the district maintained navigation channels at 17 commercial and recreational harbors, from the Mexican border to Morro Bay. This included maintaining the ports of Los Angeles and Long Beach, which handle roughly 40 percent of all U.S. trade by volume. The district also pushed forward on major flood-risk management infrastructure, nearing the start of new modification project major construction at both Prado and Whittier dams.
Bost, who previously served as the deputy commander of the USACE Great Lakes and Ohio River Division, then addressed the district for the first time as commander.
“The men and women of the LA District, it is the honor of a lifetime to join this team and serve as your commander,” Bost said. “This district’s greatest strength is its people. Together, we’ll build on this foundation with trust, open communication and a relentless commitment to delivering to the American people.”
This article was originally published by the U.S. Army Corps of Engineers under the title, “USACE LA District marks change of command near historic San Pedro Breakwater.”
