A new project is underway to address the constantly damp Castillo Street undercrossing at Highway 101, which has been a source of frustration for residents.

The project will begin Monday night between 8 p.m. and 6 a.m. and last for four weeks. Workers will add new drains to the southern portion of the undercrossing to help prevent water from building up in the road.

“We have on the north end of Castillo an underdrain that was constructed and, at this point in time, is still providing some benefit and continues to perform well,” said Jim Shivers, a public information officer for Caltrans.  

“The idea is to use something similar on the southern portion of Castillo.”

During construction, Castillo Street’s northbound shoulder, bike path lane, and sidewalk will be closed, and pedestrians will be detoured.

Flag wavers and traffic signs will also be in place to direct traffic.

Construction will take place overnight, but Shivers says that the noise and lights from the construction will be minimal.

Shivers also said the decision to do construction overnight was to avoid disrupting residents in the area who need to get to work, school or appointments.

Water issues near the undercrossing have been a longtime issue for locals, who have complained that the soggy road causes accidents and other issues.

One of the reasons given for the constant moisture is the location of the undercrossing, which sits below the water table. The position of the bridge causes groundwater to constantly seep through and flood the area.

Over the years, city officials and Caltrans have tried to address complaints about the area and make it safer.

In 1999, crews used interlocking pavers to stop water from pooling, but they eventually loosened and failed. In 2015, Caltrans crews attempted to use pavers with concrete curbs to keep them locked in place, but those failed as well.

In 2017, the agency installed a reinforced 3- to 4-inch concrete slab to the current pavement to improve the issue. The project cost $1.5 million.

In April, the city of Santa Barbara approved funding for raised bike paths and widening the sidewalks near the undercrossing. The overall project will be between $10 to $12 million.

According to Bryan Latchford, community engagement manager for the city of Santa Barbara, the city is still planning on moving ahead with the changes to the street.   

“The Caltrans work will not have an impact on any planned work to Castillo Street,” Latchford said.

For the new project, Shivers says that he is optimistic due to how the drains have helped on the northbound portion of the undercrossing.

He says that engineers have multiple tools in their toolbox but that they are attempting to deal with the forces of nature.

“We remain optimistic about our work,” Shivers said. “And again, to reinforce the point, we’re dealing with a really strong, powerful act of mother nature with the groundwater being so close to the roadway.”