CARLSBAD — While some residents are eager to move a one-mile stretch of South Carlsbad Boulevard further inland to escape sea-level rise, the city is pumping the brakes to determine the best way forward.
During an April 23 meeting, staff presented findings from a study funded through a $533,175 grant by the California State Coastal Conservancy. The study explored ways to redesign a section of Carlsbad Boulevard prone to flooding and vulnerable to future rising seas.
According to scientific modeling, the 1-mile stretch of southbound Carlsbad Boulevard between Manzano Drive and Island Way will experience some effects from rising sea levels over the next 96 years.
The grant study included a conceptual design that showed how the road could be moved away from the coastline, an adaptive management plan that would guide how and when to move the road eastward, a cliff erosion assessment and a habitat restoration analysis of the Las Encinas Creek area.
The study also weighed two options for the City Council to consider in the future: a “retreat now” option that would move the entire segment of road from the coast at once or a phased approach that would move the vehicle lanes to the east as needed and repurpose the old road for walking and biking paths that can be used as long as they are safe.
The phased approach breaks up the 1-mile road segment into four sections separated by intersecting roads, including Palomar Airport Road, Solamar Drive, Las Encinas Creek and Island Way.
Each section has “triggers” or concerns that dictate when retreat should occur.
Cliff erosion is the main trigger for the Palomar Airport section, which would require narrowing and relocating trails over time to keep the roadways close but safe from the ocean. Meanwhile, the Solamar Drive segment would address its threat of cliff erosion through increased access and erosion control while using roundabouts there as long as possible before switching to a signalized intersection.
Locals refer to the Las Encinas Creek segment as “the dip,” which floods during coastal storms. Moving this portion back would include habitat restoration along the creek, a new bridge and the formation of a possible 700-foot pocket beach with dunes and wetlands.
The study did not identify any triggers for the Island Way segment because the relocated infrastructure is already outside the coastal hazard zone.
Staff noted a continued need to work with the California State Parks agency due to potential impacts on state land at South Carlsbad State Beach.
According to Senior Program Manager Katie Hentrich, this is one of the few adaptive management plans created by coastal cities throughout the state. Because creating retreat plans is relatively new, Hentrich said best practices may evolve and provide additional guidance in the future.
Staff also advised the City Council to consider pairing the 1-mile segment project with a longer-term, 3-mile project from Manzano Drive to the city’s southern border at La Costa Avenue. The project seeks to move the southbound lanes of Carlsbad Boulevard to the east and repurpose 60 acres of coastal land for recreational and other uses.
Several residents also spoke in favor of the council opting for the retreat-now option.
“We can preserve and restore this beautiful place,” Janis Jones said. “It’s already, to me, one of the most beautiful places on the planet, but imagine how much more beautiful it would be if restored to its natural state.”
Alex Ferron, a living shoreline coordinator with the Surfrider Foundation, urged the city to follow the retreat-now option.
Unlike many other coastal cities, Ferron said Carlsbad is fortunate to have enough space to move the road inland.
“Carlsbad can lead the way in proactive planning by simply maintaining momentum in action and adopting retreat now as the city’s preferred method,” she said. “This isn’t just about infrastructure — it’s about protecting our playground, our environment, and the way we access and experience the coast for many generations to come.”
Despite several comments from the public and the Beach Preservation Commission in early April recommending the city retreat now, the staff is not yet ready to recommend either option to the City Council.
“At this time, we have to do extensive studies to determine what is feasible,” said Transportation Director and City Engineer Tom Frank. “We have to do geological studies, study more about coastal access, study what crossing that waterway looks like, and study the conceptual designs completed to date.”
Cost is another concern. Frank said the potential bridge at Las Encinas Creek alone could cost more than $150 million. “That’s just an example of the magnitude of costs we’re talking about,” he said.
A funding source has yet to be determined. Funding from the grant study ended in February.
The city aims to complete the preliminary design and permitting by 2028.
City Council asked staff to return with information about climate resilience districts, which could be a tool for raising money to plan and implement climate mitigation or adaptation projects like the Carlsbad Boulevard retreat.
According to the city, these districts can be created to address sea level rise, extreme heat or cold, and the risk of wildfires, drought and flooding.
