Planning commission approves five-year permit for Agua Hedionda lagoon maintenance dredge

The Carlsbad Planning Commission on Nov. 20 approved a five-year special use permit for maintenance dredging of the Agua Hedionda outer lagoon, a project city staff said will remove roughly 392,400 cubic yards of sand with up to 59,000 cubic yards of overdredge (a maximum of about 451,000 cubic yards) and place tested material onto Carlsbad State Beach.

Assistant Planner Nicole Morrow, who presented the application, said the lagoon — created in 1954 and maintained periodically — requires dredging approximately every two to three years to preserve the lagoon structure and ensure the nearby Claude Bud Lewis Desalination Plant has a consistent seawater intake. "The projected timeline for the project consists of approximately 110 days of work, broken down into five phases," Morrow said, adding the work could start as early as January 2025 and must be completed by April 15, 2025 to avoid nesting and spawning seasons.

Morrow told the commission the project includes beach deposition at three carrier sites on Carlsbad State Beach and that dredged sand will be tested for contaminants and compatibility before placement. She summarized outreach efforts, saying over 600 early notices were mailed Sept. 6, 2024, newspaper notices ran Nov. 8, and a City Planner's CEQA exemption was posted Oct. 7, 2024 with no appeals filed.

Adam Gale of Anchor QEA, the consultant whose firm was identified by staff as participating on the project, described the sediment testing and approval process through the Dredge Material Management Team (DMMT). "For this project, the regulatory agencies approved what's called a Tier 1 analysis, which is physical dredge materials, PCBs, DDTs and mercury primarily, they were all very, very low," Gale said, explaining that a sediment suitability finding from the DMMT is the basis for placing material on the beaches.

Paul, executive director of capital projects for Channel Side (the entity that owns and operates the desalination plant), told the commission the oyster farm near the lagoon had wrapped up operations and that the planned dredging would not affect it. On concerns about timing and permits, Gale said the applicant has secured or is close to securing several permits (including regional board and state lands components) and meets regularly with the Army Corps project manager; he noted weather and permitting remain risks to schedule.

Commissioners asked about dredge frequency and measurement; Gale explained volume estimates derive from bathymetric surveys and engineering design and include a 20% contingency to account for accumulation between survey and construction. Commissioners also discussed the convenience of a five-year permit that would allow multiple maintenance cycles without returning to the commission for each cycle.

Commissioner Means moved to approve staff's recommendation; Commissioner Myers seconded. The motion passed 6–0, with Commissioner Joseph Stine listed as absent in the transcript. The approval is conditioned on the issuance of all required state and federal permits and adherence to conditions in the permit.

The commission closed the public hearing after no members of the public signed up to speak and moved to other business. The city planner noted upcoming meeting dates and a tentative cancellation of the Dec. 18 meeting; the commission adjourned with Thanksgiving wishes from the chair.

What the approval means: the permit authorizes routine maintenance dredge cycles over a five-year period but does not replace or override required approvals by other agencies such as the Army Corps of Engineers, state parks, or regional water boards. The applicant must secure sediment suitability through interagency review before beach placement and comply with the April 15 seasonal cutoff for completion.