SAN DIEGO — A major project is underway right now to add a second rail track in Carlsbad to help alleviate congestion in the area.
The ultimate goal is to replace the aging Batiquitos bridge with a new double track one.
But before construction can begin, SANDAG needs to ensure they're protecting certain species that live in the water below.
On Friday, they sent members of their management construction team into the lagoon equipped with an inflatable boat, sonar equipment and diving gear.
It's not the type of work most people think of when it comes to building a new bridge.
But, in this case, it's crucial.
"For in lagoon work, we want to be extra extra safe," said Tim Pesce, a senior environmental planner with SANDAG.
Pesce said divers are looking for two specific species.
One is a plant that benefits the lagoon. The other is a form of algae that does not.
"One is eelgrass. It's a very, very important species to the ecosystem of the lagoon. It's a fish habitat. Fish feed on it. They nurture in it. It's a very, very critical species. So, we want to make sure that it is not in the project footprint, and if it is in the project footprint, we take the proper steps to maintain it," said Pesce.
"They're also looking for an invasive species called Caulerpa. So, if that species is there, we want to make sure that we work for the resource agencies to get rid of it."
Once that environmental research and follow up is complete, it puts SANDAG one step closer to breaking ground on the "Batiquitos Lagoon Double Track Project."
At an estimated cost of $165 million, it will add 0.6 miles of second rail track from Carlsbad to Encinitas, which will include tearing down the 1940's wooden bridge above the lagoon, and replacing it with a modern, double track concrete one.
"North of here is existing double track up to Poinsettia station, and then this existing bottleneck begins running south through Leucadia. So the goal of the project is to double track that so that the operators have flexibility to run more trains and provide more reliable service," said Pesce.
The track is part of the Los Angeles - San Diego - San Luis Obispo coastal rail corridor, which SANDAG says is the second busiest intercity passenger rail line in the United States.
SANDAG is working alongside Caltrans as part of a larger project to not only double track rail lines in the region, but also widen the five freeway.
"We have permits with every resource agency you can imagine, and we're all doing what we can to protect the sensitive resources and minimize our impacts," said Sue Scatolini, a biologist with Caltrans.
If Caulerpa is found, it could delay the project based on the need for removal.
As of right now, construction is expected to last four years and be complete in 2028.
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