Where SANDAG is proposing to add tunnels to underground Del Mar's railroad tracks

SANDAG has unveiled three proposals that would relocate inland and underground the railroad tracks that run along the Del Mar bluffs, and it's asking for public feedback before it submits its proposal.

The transportation agency has presented three alternative tracks for the 1.7-mile stretch of the Los Angeles-San Diego-San Luis Obispo rail corridor that runs atop the eroding cliffside between Sorrento Valley and Solana Beach.

All three options would move the existing single-track route away from the bluffs in Del Mar into a double-track rail that passes through a tunnel under the hillside, but each plan differs from there. Take a closer look below:

Alternative A

In the first of three plans, there would no longer be an above-ground train track in Del Mar. Trains would enter and exit a tunnel between Carmel Mountain Road and state Route 56.

The underground tracks would then run in line with Interstate 5 before veering back to the coastline beneath the San Dieguito Lagoon to reconnect with the existing railway near the fairgrounds. Infrastructure would also fall within the Los Peñasquitos Lagoon area.

The Fairgrounds North tunnel would start south of the existing Solana Beach station and the train tracks would extend under the fairgrounds, where a new underground special events platform would be created, SANDAG said.

Alternative B

Version two has one tunnel entrance at the same Carmel Valley location. The second entrance is near Jimmy Durante Boulevard south of the Del Mar Fairgrounds, which would need to be raised to accommodate the tunnel, SANDAG said. This proposal would bury the train tracks under a portion of the Torrey Pines State Reserve and the city of Del Mar as opposed to the interstate and lagoon in alternative A.

Alternative C

The final plan has the shortest tunnel portion, entering near Torrey Pines State Beach's north parking lot and exiting under Jimmy Durante Boulevard. Instead, a bridge would take the train tracks over Los Peñasquitos lagoon. The existing tracks around the lagoon would also need to be expanded and raised, SANDAG said.

The portal infrastructure could extend into residential properties, SANDAG said. It also appears to be the most minimal relocation of the three plans with only a short portion of the railway moving slightly inland near Camino Del Mar.

The project could cost up to $4 billion but SANDAG expects much of the funding to come from state and federal resources. The state has already designated about $300 million to the project's planning and design phases. More specific estimates will be made during the environmental analysis.

It should be noted that the environmental impact report that SANDAG will submit to the state must also consider a "no project" alternative. But the agency says a plan for moving the railway to a more "climate resilient area" is necessary as bluff collapses in the area become more frequent and as the need for faster and more frequent service increases.

Researchers attribute erosion to climate change, sea level rise and more intense storms.

"The segment of the San Diego Subdivision within the SDLRR Project area has experienced temporary closures and speed reductions resulting from bluff collapses, erosion, and repair work to stabilize the bluffs and protect the rail corridor from more substantial erosion effects," a notice about the project reads.

SANDAG has already spent millions to prevent bluff erosion. They have started adding seawalls at the base of the bluffs and have added structures under the tracks to increase stability. But a longer term solution is necessary, the agency says.

“One of the benefits of moving the tracks off the bluff is that we’ll have a straighter alignment, it’ll be more efficient,"  Omar Atayee, director of engineering and construction for SANDAG, told NBC 7 in May. "We’ll also have double tracks. In this area, there’s only one track, so giving us two lines of track gives us more operation, more service and more reliability.”

Undergrounding the tracks and doubling their capacity would also allow SANDAG to increase ridership and speed, they say.

How to share your feedback?

The proposals must not only face the public, but must also be analyzed to determine which are most technically feasible and which align with environmental impact goals.

The public can provide feedback on the plans by submitting the form here by July 19. They can also be sent via email with subject line “SDLRR Project NOP” to: LOSSANcorridor@sandag.org. Written comments can be sent by mail to:

SANDAG, ATTN: Tim Pesce
401 B Street, Suite 800
San Diego, CA 92101

SANDAG will also hold a public meeting on Tuesday, June 18, from 6-7:30 p.m. at the San Diego Marriott Del Mar (11966 El Camino Real).

Feedback will be presented as part of a Draft Environmental Impact Report, which is required before the project can move forward. The environmental report's entire process can take anywhere from 18-24 months to complete so any potential construction is still years away. The agency said if all goes well, the new tracks should be finished no later than 2035.