Still 10 years away in “a perfect world,” probably much longer
In “a perfect world,” with construction money and permits in hand, a train tunnel could be built through Del Mar in less than 10 years, transit officials said last week. But that’s not likely.
In reality it probably will take two or three times that long to move the tracks off the eroding coastal bluffs, according to an update presented at a North County Transit District board meeting in Oceanside.
“We don’t (even) have $5 for a tunnel,” said transit district Executive Director Matt Tucker. In addition to the money, extensive planning and design, environmental studies and other work would be needed before construction can start. Public opinion is another factor, and any large-scale project would need widespread political support.
“Every project I’ve been around, you are typically talking a 30- or 40-year time frame,” Tucker said.
Transportation officials have talked since at least 1980 about rerouting the train tracks through an inland tunnel, possibly along Interstate 5, to avoid the bluffs at the edge of the Pacific Ocean. Little progress has been made, though, and recently the cost of a tunnel was estimated at $3 billion.
Meanwhile, coastal erosion eats away the bluffs at an average rate of six inches a year. The rate varies, from nearly nothing in dry and uneventful years, to large rail-threatening chunks during wet winters, big storms or an earthquake.
NCTD and the San Diego Association of Governments launched a six-phase program in 2000 to stabilize the Del Mar cliffs through 2050. Construction of the fourth phase is underway, and planning has begun for the fifth.
A series of vertical concrete and steel columns buried in the ground on the railroad right-of-way atop the bluff are the backbone of the stabilization effort. It also includes drainage structures to carry rainwater and irrigation runoff away from the tracks and safely to the beach.
“Twenty years ago, we weren’t concerned about sea-level rise,” said Patricia McColl, a civil engineer with the consulting firm HNTB in San Diego, who presented an update on bluff projects to the NCTD board.
“Now we are looking at significant toe erosion (at the base of the bluffs) that will accelerate with sea level rise,” she said.
“Toe protection is not a popular idea,” she said, because it requires installing seawalls, revetments or other hard structures to protect the base of the bluffs.
Seawalls can contribute to beach erosion and are opposed by environmental groups such as the Surfrider Foundation and the Sierra Club.
The tracks on the Del Mar bluffs are used by Coaster commuter, Amtrak passenger and BNSF freight trains. It is the only rail link between Los Angeles and San Diego.
— Phil Diehl is a reporter for The San Diego Union-Tribune